Publications - Publikationer

Animal discomfort

Thu, 01 Aug 2024 04:38:58 +0200

The term discomfort is frequently used in for example biomedical studies, animal experimentation for farming purposes, animal welfare legislation, and ethical permits for animal experimentation. However, the concept of “animal discomfort” still remains unclear. Using the domesticated pig as a model, we performed a Walker and Avant concept analysis to develop an operational definition of animal discomfort. A total of 2,594 documents published in English were retrieved from Scopus database. Among them, 118 were retained for analysis as they contained either: 1 - a definition and/or measurement of discomfort in animals, including pigs; 2 – definition and/or measurement of pain, suffering, or sickness in pigs only. The literature review showed that animal discomfort intersects on three domains: physical, physiological, and mental discomfort. The presence of discomfort leads to a sense of uneasiness that results in behaviorally visible consequences comprising animals’ attempts to avoid or alleviate the source(s) of this affective state. Accordingly, our proposed operational definition of animal discomfort is: short- or long-lived negative affective state featured by physical, physiological and/or mental components, induced by internal or external stimuli, ranging from mild to severe, potentially occurring together with other negative affective states, and leading to avoidance or attempt to alleviate the source of uneasiness. Access to a shared definition of this central concept in animal welfare may be one initial step to facilitate legislation consistency, improve animal research integrity, and ultimately promote a more sustainable livestock production.

Application of polyurethane foam matrix as immobilizer in the production of thermostable alkaline protease by Bacillus subtilis isolated from barbecue spots

Wed, 01 Jan 2014 04:38:58 +0100

Polyurethane foam (PUFoam) was used as an immobilization platform for the production of alkaline protease by Bacillus subtilis isolated from barbecue spots. Five B. subtilis isolates were subjected to alkaline protease assay. Among the isolates, B. subtilis IK17 exhibited highest alkaline protease production in a 48 h single batch (peak value, 20.3 AU mL⁻¹) at 40 h incubation time and was selected for immobilization studies. Effects of PUFoam volume, density and treatment in gluteraldehyde concentrations on enzyme yield were assessed. Increase in volume resulted in increased enzyme yield as volume of 3.375 cm³ yielded a peak enzyme value of 27.2 AU mL⁻¹; 1 cm³ foam volume led to peak enzyme value of 24.1 AU mL⁻¹ while 0.125 cm³ gave a peak value of 23.8 AU mL⁻¹ at 48 h. Higher foam density led to a reduced enzyme activity as peak values obtained at 48 h incubation showed 2 g cm⁻³= 23.8 AU mL⁻¹; 1 g m⁻³ = 24.2 AU mL⁻¹ and 0.5 g cm⁻³ = 28.22 AU mL⁻¹. Effects of concentrations of gluteraldehyde exhibited maximum activity of 26 AU mL⁻¹ for 5% gluteraldehyde followed by 25.4 AU mL⁻¹ for 1% gluteraldehyde and 21.6 AU mL⁻¹ for 10% gluteraldehyde. Up to 10 repeat cycles were conducted for enzyme production using immobilized and free cells of B. subtilis IK17 with free cells performing in only 2 cycles with peak total titre value of 100 AU mL⁻¹ during the 1st cycle while immobilized cells produced enzyme for up to 9 cycles with peak total titer value of 200 AU mL⁻¹ during the 4th cycle. The PUFoam cell leakage assessments showed that as concentration of gluteraldehyde was reduced, it resulted in higher cell leakage. Higher cell leakage was also observed in higher densities of foam while lower foam volumes resulted in higher cell leakage.

Characterization of the Endometrial Transcriptome in Early Diestrus Influencing Pregnancy Establishment in Dairy Cattle after Transfer of In-Vitro Produced Embryos

Wed, 01 Jan 2020 04:38:58 +0100

Climate-driven deoxygenation of northern lakes

Jansen, J., Simpson, G. L., Weyhenmeyer, G. A., et al. — Mon, 01 Jul 2024 04:38:58 +0200

Oxygen depletion constitutes a major threat to lake ecosystems and the services they provide. Most of the world’s lakes are located >45° N, where accelerated climate warming and elevated carbon loads might severely increase the risk of hypoxia, but this has not been systematically examined. Here analysis of 2.6 million water quality observations from 8,288 lakes shows that between 1960 and 2022, most northern lakes experienced rapid deoxygenation strongly linked to climate-driven prolongation of summer stratification. Oxygen levels deteriorated most in small lakes (<10 ha) owing to their greater volumetric oxygen demand and surface warming rates, while the largest lakes gained oxygen under minimal stratification changes and improved aeration at spring overturns. Seasonal oxygen consumption rates declined, despite widespread browning. Proliferating anoxia enhanced seasonal internal loading of C, P and N but depleted P long-term, indicating that deoxygenation can exhaust redox-sensitive fractions of sediment nutrient reservoirs.

Effect of dietary protein for gestating sows on re-establishment of body reserves and impact on reproductive performance

Johannsen, J. C., Sørensen, M. T., Feyera, T., Pelck, J. S., Bruun, T. S. — Thu, 01 Aug 2024 04:38:58 +0200

This study aimed to investigate the effect of increasing dietary protein during gestation on sows’ ability to re-establish body reserves and evaluate the impact on reproductive performance of multiparous sows. The experiment was carried out in a commercial Danish herd and 431 sows were included and allotted to one of five dietary treatments. The treatment period extended from the time of service until the sows were moved to the farrowing section, approximately 5 d before expected farrowing. Experimental diets were isoenergetic and contained increasing concentrations of dietary protein (standardized ileal digestible [SID] lysine [Lys]; 3.37 to 6.39 g/kg). Sow body weight (BW) and backfat (BF) were recorded at service, on d 28 and 84 of gestation, and one to three days post-farrowing. Live and stillborn piglets and piglet birth weight were recorded. Sow body protein and fat were estimated; however, body fat estimations were considered inaccurate. Moreover, the feed and Lys to BW gain ratios were calculated. In early gestation, the BW and body protein gain of parity 2 to 3 sows increased linearly with increasing SID Lys (P < 0.001), while in mid-gestation BW gain had a polynomic response to SID Lys (P < 0.001), showing that BW gain was maximized at 5.0 g SID Lys/kg diet. Above the maximal BW gain sows’ body protein gain reached a plateau (P < 0.001) and Lys to BW gain ratio increased (P < 0.001), indicating oxidation of excess protein. In contrast, sow BW and body protein gain of parity 4 to 5 did not change with increasing SID Lys in most gestation stages, indicating that maternal growth was limited by energy intake. Sow BF gain did not change with increasing SID Lys, even though increasing SID Lys presumably increased the energy costs for protein retention or oxidation. Sow reproductive performances were not affected by dietary treatment, showing that fetuses are highly prioritized. In conclusion, sows of parity 2 to 3 re-established more BW and body protein than parity 4 to 5, when fed increasing dietary protein (SID Lys) during gestation. The dietary concentration of SID Lys did not affect sow reproduction in terms of litter size and average piglet birth weight; thus, SID Lys should be kept low during gestation until approximately one week prior to farrowing, and yet allow sows to re-establish sufficient body reserves for mobilization in the following lactation.

Proteins from cultivated mammary epithelial cells derived from bovine milk

Che, J., Yue, Y., Nielsen, S. D., Purup, S., Poulsen, N. A., Larsen, L. B. — Sat, 01 Jun 2024 04:38:58 +0200

Måske skulle vi arbejde mere med begrebet transportegnethed

Herskin, M. S., Putzer, A. . — Mon, 26 Feb 2024 04:38:58 +0100

Correction

Cronin-Fenton, D. P., Christensen, M., Lash, T. L., Ahern, T. P., Pedersen, L. — Tue, 11 Mar 2014 04:38:58 +0100

Redegørelse og vurdering af metoder der benyttes til beregning af landbrugets udledninger

Olesen, J. E., Langen, P. L., Munkholm, L. J., et al. — Mon, 08 Jul 2024 04:38:58 +0200

Iodoform as methane mitigating additive for dairy cows

Rønn, M. — Mon, 01 Jan 2024 04:38:58 +0100

Serum Amyloid A and Haptoglobin concentrations in calves at first event of respiratory disease were not associated with subsequent risk of respiratory disease during the preweaning period

Møller, H. H. ., Petersen, M. B., Krogh, M. A., Nielsen, L. R., Capion, N. — Thu, 01 Aug 2024 04:38:58 +0200

Bovine respiratory disease (BRD) causes decreased welfare and production losses and is a major reason for use of antimicrobials in dairy calves. Inflammatory markers released into the blood stream during BRD include acute phase proteins such as Serum Amyloid A (SAA) and Haptoglobin (Hp). This longitudinal observational study aimed to investigate whether the serum concentrations of SAA and Hp measured on the day of a detected mild clinical event of BRD, were associated the odds of developing recurrent BRD events requiring additional treatments in up to a 46-day follow-up period after the first event. A total of 65 preweaned dairy calves were observed for 46 days each in one Danish dairy herd. They were enrolled in this study in the age between 17 and 24 days of age and were followed for the following 46 days in total in which the calves potentially could develop an event of BRD. The calves were clinically assessed every other day using a Visual Analogue Scale (VAS), where a mild BRD event was defined as a calf that deviated from a normal and non-affected calf. The clinical signs included that the calf was less interested in its surroundings, slightly depressed, less bright, alert, and responsive with less clear eyes and using longer time to get up. The calf could have scruffy hair coat and drooping ears. Blood samples were collected on the day of the first mild BRD event that was only treated with a non-steroidal anti-inflammatory drug. A logistic regression model was performed to detect associations between having recurrent events of BRD and VAS, serum SAA and Hp concentrations at the day of the first BRD event and the follow-up period after the BRD event. Only the follow-up period after the first BRD event had a significant association with the odds ratio of having recurrent events of BRD of 2.3 for a 10-day difference in follow-up time after the BRD event.

How much can performance measures explain of the between-cow variation in enteric methane?

Giagnoni, G., Friggens, N. C., Johansen, M., et al. — Mon, 01 Jul 2024 04:38:58 +0200

Enteric CH₄ produced from dairy cows contributes to the emission of greenhouse gases from anthropogenic sources. Recent studies have shown that the selection of lower CH₄-emitting cows is possible, but doing so would be simpler if performance measures already recorded on farm could be used, instead of measuring gas emissions from individual cows. These performance measures could be used for selection of low emitting cows. The aim of this analysis was to quantify how much of the between-cow variation in CH₄ production can be explained by variation in performance measures. A dataset with 3 experiments and a total of 149 lactating dairy cows with repeated measures was used to estimate the between-cow variation (the variation between cow estimates) for performance and gas measures from GreenFeed (C-Lock, Rapid City, SD). The cow estimates were obtained with a linear mixed model with the diet within period effect as a fixed effect and the cow within experiment as a random effect. The cow estimates for CH₄ production were first regressed on the performance and gas measures individually, and then performance and CO₂ production measures were grouped in 3 subsets for principal component analysis and principal component regression. The variables that explained most of the between-cow variation in CH₄ production were DMI (R² = 0.44), among the performance measures, and CO₂ production (R² = 0.61), among gas measures. Grouping the measures increased the R² to 0.53 when only performance measures were used, and to 0.66 when CO₂ production was added to the significant performance measures. We found the marginal improvement to be insufficient to justify the use of grouped measures rather than an individual measure because the latter simplifies the model and avoids over-fitting. Investigation of other measures that can be explored to increase explanatory power of between-cow variation in CH₄ production is briefly discussed. Finally, the use of residual CH₄ as a measure for CH₄ efficiency could be considered by using either DMI or CO₂ production as the sole predicting variables.

A retrospective cohort study investigating the association of individual quarter dry-off with udder health, milk production, and culling risk

Wieland, M., Skarbye, A. P. — Mon, 01 Jul 2024 04:38:58 +0200

Individual quarter dry-off (QDO) has been increasingly employed as a strategy for managing cows with chronically elevated SCC and recurrent clinical mastitis. However, little knowledge is available on the effects of QDO on milk production, SCC, the risk of clinical mastitis, and the risk of removal from the herd. Therefore, this retrospective cohort study aimed to investigate these associations. Data from 471 dairy cows subjected to QDO were analyzed. The cows were housed on a 4,000-cow dairy farm with a thrice-daily milking schedule. The cows were grouped based on the reason for QDO: (1) cows detected with a nonlactating quarter at a fresh cow check (QFRESH); (2) cows with recurrent clinical mastitis (QMAST); (3) cows diagnosed with Staphylococcus aureus IMI (QSA); and (4) cows with chronic subclinical mastitis (QSCC). Additionally, we randomly selected herd mates at a ratio of 1:1 to serve as a control group (CON). Cows in the CON group were matched in terms of parity and stage of lactation. Generalized linear mixed models with an identical link were used to estimate milk yield and SCC at 1 test day before QDO (T-1) as well as 1, 2, and 3 (T1, T2, and T3) test days after QDO. All cows subjected to QDO exhibited a decrease in milk yield following QDO compared with their respective control groups. All QDO cows approached the yield of their control group by T3. In particular, the difference in milk yield between QMAST cows and their controls at T3 was less than the difference at T1. Cows in the QMAST and QSCC groups exhibited a decrease in their SCC following QDO. In particular, the SCC was significantly higher among QMAST cows than among their controls at T1, but this difference was no longer significant by T3. Proportional hazards regression models revealed that QDO was associated with clinical mastitis occurrence and removal from the herd. Compared with CON cows, the hazard ratio (95% CI) for clinical mastitis occurrence was 3.70 (1.65–8.28), 1.80 (1.31–2.47), and 2.27 (0.93–5.54) among QFRESH, QMAST, and QSA cows, respectively. The hazard ratio among QSCC cows was modified by the effect of parity. The hazard ratio (95% CI) for removal from the herd was higher among cows subjected to QDO than among CON cows (hazard ratio [95% CI] values of 2.30 [0.99–5.33], 3.27 [2.20–4.86], and 4.87 [1.81–13.12] for QFRESH, QMAST, and QSCC cows, respectively). We conclude that QDO can be a viable strategy for managing cows with recurrent clinical mastitis. However, the results for the cows that underwent QDO for other reasons are less clear, partially due to low statistical power. Therefore, future research should examine how to decrease the risks of clinical mastitis and removal from the herd among cows subjected to QDO.

Sows and piglets adjust their use of an outdoor paddock with season and piglet age during the first weeks of life in an organic farm

Jahoui, A., Malmkvist, J., Pedersen, L. J., Lieubeau, B., Hervé, J., Tallet, C. — Mon, 01 Jul 2024 04:38:58 +0200

Few studies have examined sows and piglets' use of outdoor access during their first weeks of life, when reared with access to a hut and a pasture as in the organic system. We studied whether the age of the piglets and the season of the year influenced the use of an outdoor area by piglets and the sow, and the use of indoor spaces. For this, the localisation of sows and their piglets inside and outside the hut was analysed on 16 sows and their litters during the summer and 16 others during the winter, by scan sampling, on days 2, 7 and 13 after parturition in an organic herd in Denmark. When inside the hut, the number of piglets in the creep area, next to the sow or other piglets was noted. All parameters were analysed by linear mixed-effects ANOVA models. Sows were less often observed outside the hut in the wintertime and during the mornings compared to later times of the day (P<0.001). Furthermore, the sows increased their outdoor use with the age of their litter (P<0.001). The season also influenced the piglet use of outdoor areas (winter < summer; P<0.001). Piglets that were observed outside for the first time were older (8.9±0.9 d) during winter than during summer (3.5±0.5 d). The proportion of piglets observed outside increased with age, with a significant Season x Age interaction (P<0.001). The proportion of observations where the sows and piglets were outdoors together increased with the piglets’ age (P < 0.001). Sows’ outing was correlated with summer (R=0.3) and winter (R=0.2) temperatures, unlike piglets, where outings were correlated only with summer temperatures (R=0.3, P<0.001). The proportion of piglets observed in the creep area was significantly affected by the age with a Season x Age interaction effect (P<0.001). Piglets were rarely observed lying alone inside the hut. The proportion of piglets in contact with the sow and other piglets inside the pen was influenced by a significant Age x Season interaction effect (P<0.001). We showed that piglets given access to an outside paddock gradually increase their use with age and don't go outside right away. Their first exit and the proportion of piglets outside depended also on the season. In general, a higher proportion of sows and piglets were observed indoor during the wintertime. Thus, sows and piglets adjust their use of outdoor paddock with season and piglet age during the first weeks of life.

Lactogenic treatment effects on milk synthesis genes and protein secretion in cultured bovine mammary epithelial cells

Sattari, Z., Nielsen, S. D. H., Che, J., et al. — Sun, 01 Dec 2024 04:38:58 +0100

In a cellular agriculture context, the possibility of producing milk components using tissue derived bovine mammary epithelial cells (MEC) is an upcoming strategy being considered. As an essential step, development of an in-vitro model for optimizing lactogenic activity of cultured MEC is needed. MECs were isolated from bovine mammary tissue and cultured in a trans-well system. Treatment with differentiation media (DM) was performed for 7-days. Conditioned media containing the cell secretions (the “secretomes”) were collected, and the trans-epithelial-resistance (TEER), measured. On day 7 the cells were lysed, and expression of lactation associated genes were examined using qPCR. Proteomic analysis of the secretomes was performed using timsToF Pro LC-MS/MS. DM treated cells had significantly higher TEER for several days but a general decreasing trend started on day 4. Expressions of CSN1S1, CSN2, CSN3, ELF5 and PRLR were significantly increased after DM treatment. DM significantly altered the secretome's protein compositions. Numerous proteins involved in lactogenic activity of the MEC were identified. However, the DM did not significantly impact their peak intensities. These findings shed light on areas requiring additional refinement of the in-vitro model to enhance the production of milk components. These aspects primarily comprise the DM composition and experimental length.

Lactogenic treatment effects on milk synthesis genes and protein secretion in cultured bovine mammary epithelial cells

Sattari, Z., Nielsen, S. D. H., Che, J., et al. — Sun, 01 Dec 2024 04:38:58 +0100

Klima- og miljøeffekter ved øget dyrkning af bælgsæd/proteinafgrøder

Thers, H., Dalsgaard, T. K., Jensen, S. K., et al. — Wed, 26 Jun 2024 04:38:58 +0200

Mass spectrometric analysis of the secreted protein profile of BM-MSC after IL-1beta stimulation

Bundgaard, L. — Fri, 01 Jan 2016 04:38:58 +0100

Mass spectrometric analysis of the in vitro secretome from bone marrow derived mesenchymal stem cells undergoing chondrogenic differentiation after IL-1beta stimulation

Bundgaard, L. — Sun, 01 Jan 2017 04:38:58 +0100

Mapping of the in vitro secreted protein profile of equine mesenchymal stem cells after inflammatory stimulation using quantitative mass spectrometry analysis

Bundgaard, L. — Sun, 01 Jan 2017 04:38:58 +0100

A system-wide study of the proteome and protease cleavage and protease cleavage products in chronic skin ulcers

Bundgaard, L. — Mon, 01 Jan 2018 04:38:58 +0100

How does chondrogenic differentiation and stimulation with intereukin-1ß affect the secretome from bone marrow derived mesenchymal stem cells

Bundgaard, L. — Mon, 01 Jan 2018 04:38:58 +0100

A SYSTEM-WIDE STUDY OF THE PROTEOME AND PROTEASE CLEAVAGE PRODUCTS IN CHRONIC SKIN ULCERS

Mon, 01 Jan 2018 04:38:58 +0100

Mapping the N-Terminome in Tissue Biopsies by PCT-TAILS

Bundgaard, L., Savickas, S., auf dem Keller, U. — Tue, 01 Jan 2019 04:38:58 +0100

Proteases play pivotal roles in multiple biological processes in all living organisms and are tightly regulated under normal conditions, but alterations in the proteolytic system and uncontrolled protease activity result in multiple pathological conditions. A disease will most often be defined by an ensemble of cleavage events-a proteolytic signature, thus the system-wide study of protease substrates has gained significant attention and identification of disease specific clusters of protease substrates holds great promise as targets for diagnostics and therapy.In this chapter we describe a method that enables fast and reproducible analysis of protease substrates and proteolytic products in an amount of tissue less than the quantity obtained by a standard biopsy. The method combines tissue disruption and protein extraction by pressure cycling technology (PCT), N-terminal enrichment by tandem mass tag (TMT)-terminal amine isotopic labeling of substrates (TAILS), peptide analysis by mass spectrometry (MS), and a general pipeline for interpretation of the data.

Tendon response to matrix unloading is determined by the patho-physiological niche

Wunderli, S.L., Blache, U., Beretta Piccoli, A., et al. — Wed, 01 Jan 2020 04:38:58 +0100

Although the molecular mechanisms behind tendon disease remain obscure, aberrant stromal matrix turnover and tissue hypervascularity are known hallmarks of advanced tendinopathy. We harness a tendon explant model to unwind complex cross-talk between the stromal and vascular tissue compartments. We identify the hypervascular tendon niche as a state-switch that gates degenerative matrix remodeling within the tissue stroma. Here pathological conditions resembling hypervascular tendon disease provoke rapid cell-mediated tissue breakdown upon mechanical unloading, in contrast to unloaded tendons that remain functionally stable in physiological low-oxygen/-temperature niches. Analyses of the stromal tissue transcriptome and secretome reveal that a stromal niche with elevated tissue oxygenation and temperature drives a ROS mediated cellular stress response that leads to adoption of an immune-modulatory phenotype within the degrading stromal tissue. Degradomic analysis further reveals a surprisingly rich set of active matrix proteases behind the progressive loss of tissue mechanics. We conclude that the tendon stromal compartment responds to aberrant mechanical unloading in a manner that is highly dependent on the vascular niche, with ROS gating a complex proteolytic breakdown of the functional collagen backbone.

CHRONIC SKIN ULCERS - A STUDY OF THE GLOBAL TISSUE PROTEOME AND PROTEASE CLEAVAGE PRODUCTS

Bundgaard, L., Aagren, M. S., Holstein, P., Sabino, F., auf dem Keller, U. — Wed, 01 Jan 2020 04:38:58 +0100

Global age-sex-specific mortality, life expectancy, and population estimates in 204 countries and territories and 811 subnational locations, 1950–2021, and the impact of the COVID-19 pandemic

Schumacher, A. E., Kyu, H. H., Aali, A., et al. — Wed, 01 May 2024 04:38:58 +0200

Background: Estimates of demographic metrics are crucial to assess levels and trends of population health outcomes. The profound impact of the COVID-19 pandemic on populations worldwide has underscored the need for timely estimates to understand this unprecedented event within the context of long-term population health trends. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 provides new demographic estimates for 204 countries and territories and 811 additional subnational locations from 1950 to 2021, with a particular emphasis on changes in mortality and life expectancy that occurred during the 2020–21 COVID-19 pandemic period. Methods: 22 223 data sources from vital registration, sample registration, surveys, censuses, and other sources were used to estimate mortality, with a subset of these sources used exclusively to estimate excess mortality due to the COVID-19 pandemic. 2026 data sources were used for population estimation. Additional sources were used to estimate migration; the effects of the HIV epidemic; and demographic discontinuities due to conflicts, famines, natural disasters, and pandemics, which are used as inputs for estimating mortality and population. Spatiotemporal Gaussian process regression (ST-GPR) was used to generate under-5 mortality rates, which synthesised 30 763 location-years of vital registration and sample registration data, 1365 surveys and censuses, and 80 other sources. ST-GPR was also used to estimate adult mortality (between ages 15 and 59 years) based on information from 31 642 location-years of vital registration and sample registration data, 355 surveys and censuses, and 24 other sources. Estimates of child and adult mortality rates were then used to generate life tables with a relational model life table system. For countries with large HIV epidemics, life tables were adjusted using independent estimates of HIV-specific mortality generated via an epidemiological analysis of HIV prevalence surveys, antenatal clinic serosurveillance, and other data sources. Excess mortality due to the COVID-19 pandemic in 2020 and 2021 was determined by subtracting observed all-cause mortality (adjusted for late registration and mortality anomalies) from the mortality expected in the absence of the pandemic. Expected mortality was calculated based on historical trends using an ensemble of models. In location-years where all-cause mortality data were unavailable, we estimated excess mortality rates using a regression model with covariates pertaining to the pandemic. Population size was computed using a Bayesian hierarchical cohort component model. Life expectancy was calculated using age-specific mortality rates and standard demographic methods. Uncertainty intervals (UIs) were calculated for every metric using the 25th and 975th ordered values from a 1000-draw posterior distribution. Findings: Global all-cause mortality followed two distinct patterns over the study period: age-standardised mortality rates declined between 1950 and 2019 (a 62·8% [95% UI 60·5–65·1] decline), and increased during the COVID-19 pandemic period (2020–21; 5·1% [0·9–9·6] increase). In contrast with the overall reverse in mortality trends during the pandemic period, child mortality continued to decline, with 4·66 million (3·98–5·50) global deaths in children younger than 5 years in 2021 compared with 5·21 million (4·50–6·01) in 2019. An estimated 131 million (126–137) people died globally from all causes in 2020 and 2021 combined, of which 15·9 million (14·7–17·2) were due to the COVID-19 pandemic (measured by excess mortality, which includes deaths directly due to SARS-CoV-2 infection and those indirectly due to other social, economic, or behavioural changes associated with the pandemic). Excess mortality rates exceeded 150 deaths per 100 000 population during at least one year of the pandemic in 80 countries and territories, whereas 20 nations had a negative excess mortality rate in 2020 or 2021, indicating that all-cause mortality in these countries was lower during the pandemic than expected based on historical trends. Between 1950 and 2021, global life expectancy at birth increased by 22·7 years (20·8–24·8), from 49·0 years (46·7–51·3) to 71·7 years (70·9–72·5). Global life expectancy at birth declined by 1·6 years (1·0–2·2) between 2019 and 2021, reversing historical trends. An increase in life expectancy was only observed in 32 (15·7%) of 204 countries and territories between 2019 and 2021. The global population reached 7·89 billion (7·67–8·13) people in 2021, by which time 56 of 204 countries and territories had peaked and subsequently populations have declined. The largest proportion of population growth between 2020 and 2021 was in sub-Saharan Africa (39·5% [28·4–52·7]) and south Asia (26·3% [9·0–44·7]). From 2000 to 2021, the ratio of the population aged 65 years and older to the population aged younger than 15 years increased in 188 (92·2%) of 204 nations. Interpretation: Global adult mortality rates markedly increased during the COVID-19 pandemic in 2020 and 2021, reversing past decreasing trends, while child mortality rates continued to decline, albeit more slowly than in earlier years. Although COVID-19 had a substantial impact on many demographic indicators during the first 2 years of the pandemic, overall global health progress over the 72 years evaluated has been profound, with considerable improvements in mortality and life expectancy. Additionally, we observed a deceleration of global population growth since 2017, despite steady or increasing growth in lower-income countries, combined with a continued global shift of population age structures towards older ages. These demographic changes will likely present future challenges to health systems, economies, and societies. The comprehensive demographic estimates reported here will enable researchers, policy makers, health practitioners, and other key stakeholders to better understand and address the profound changes that have occurred in the global health landscape following the first 2 years of the COVID-19 pandemic, and longer-term trends beyond the pandemic. Funding: Bill & Melinda Gates Foundation.

Amino acid requirements for BSFL

Schøn, M. L., Berggreen, I. E., Jensen, K., Nørgaard, J. V. — Wed, 06 Dec 2023 04:38:58 +0100

Risikovurdering for id-nummer 24-H3-01-02 (Stoffet)

Jensen, M. B., Krogh, M. A. — Fri, 21 Jun 2024 04:38:58 +0200

Dairy cows’ motivation to nurse their calves

Jensen, E. H., Bateson, M., Neave, H. W., Rault, J. L., Jensen, M. B. — Sun, 01 Dec 2024 04:38:58 +0100

When weaning offspring, female mammals limit nursing opportunities. This study aimed to investigate whether imposing a gradual reduction in daily contact time, by separating cows from their calves as an attempt to stimulate weaning, reduced dairy cows’ motivation to nurse their calves. For seven weeks, 84 Holstein–Friesian cow-calf pairs were housed with either full-time (23 h contact/d), part-time (10 h contact/d), or no contact. In the following two weeks, half of full- and part-time pairs were subjected to reduced contact (50% of initial contact in week 8, 25% of initial contact in week 9), while the other half continued with unchanged contact. In weeks 8 and 9, cows’ motivation to obtain full contact to and opportunity to nurse their calves was measured using weighted push gates using a novel maximum price paid method providing an alternative choice to the cows to reduce frustration. Cows with reduced calf contact were more motivated than cows with unchanged contact; however, cows used the alternative choice less than expected. The results show that cows’ motivation for full calf contact and opportunity to nurse increases when daily calf contact is reduced, illustrating that dairy cows are motivated to continue nursing their 9- to 10-week-old calves.

Biomarkers for ideal protein

Marín-García, P. J., Llobat, L., Cambra-López, M., et al. — Sun, 01 Dec 2024 04:38:58 +0100

With the main aim of identifying biomarkers that contribute to defining the concept of ideal protein in growing rabbits under the most diverse conditions possible this work describes two different experiments. Experiment 1: 24 growing rabbits are included at 56 days of age. The rabbits are fed ad libitum one of the two experimental diets only differing in lysine levels. Experiment 2: 53 growing rabbits are included at 46 days of age, under a fasting and eating one of the five experimental diets, with identical chemical composition except for the three typically limiting amino acids (being fed commercial diets ad libitum in both experiments). Blood samples are taken for targeted and untargeted metabolomics analysis. Here we show that the metabolic phenotype undergoes alterations when animals experience a rapid dietary shift in the amino acid levels. While some of the differential metabolites can be attributed directly to changes in specific amino acids, creatinine, urea, hydroxypropionic acid and hydroxyoctadecadienoic acid are suggested as a biomarker of amino acid imbalances in growing rabbits’ diets, since its changes are not attributable to a single amino acid. The fluctuations in their levels suggest intricate amino acid interactions. Consequently, we propose these metabolites as promising biomarkers for further research into the concept of the ideal protein using rabbit as a model.

Delineating Mastitis Cases in Dairy Cows

Khan, M. F., Thorup, V. M., Luo, Z. — Mon, 01 Jul 2024 04:38:58 +0200

Mastitis, an intramammary bacterial infection, is not only known to adversely affect the health of a dairy cow but also to cause significant economic loss to the dairy industry. The severity and spread of mastitis can be restrained by identifying the early signs of infection in the cows through an intelligent decision support system. Early intervention and control of infection largely depend on the availability of on-site high throughput machinery, which can analyze milk samples regularly. However, due to limited resources, marginal and small farms usually cannot afford such high-end machinery, hence, the financial loss in such farms due to mastitis may become significant. To overcome such limitations, this article proposes a low-complexity yet affordable automated system for accurate prediction of early signs of clinical mastitis infection in dairy cows. In this work, behavioral data collected through Internet of Things (IoT)-enabled wearable sensors for cows is utilized to develop a support vector machine (SVM) model for the daily prediction of mastitis cases in a dairy farm. The dataset from the research herd utilizes the information of 415 cows collected in the span of 4.75 years in which 75 cows had mastitis. In addition to relevant behavioral features, other statistically significant features, such as daily milk yield, lactation period, and age are also utilized as features. Our study indicates that the SVM model comprising a subset of behavioral and nonbehavioral features can deliver a mastitis prediction accuracy of 89.2%.

Forekomst af brom og bromforbindelser i tang til kvægfoder og den relaterede risiko for dyresundheden samt risiko for overførsel til fødevarer af animalsk oprindelse

Nørskov, N. — Mon, 17 Jun 2024 04:38:58 +0200

Delineation of chicken immune markers in the era of omics and multicolor flow cytometry

Härtle, S., Sutton, K., Vervelde, L., Dalgaard, T. S. — Wed, 01 May 2024 04:38:58 +0200

Multiparameter flow cytometry is a routine method in immunological studies incorporated in biomedical, veterinary, agricultural, and wildlife research and routinely used in veterinary clinical laboratories. Its use in the diagnostics of poultry diseases is still limited, but due to the continuous expansion of reagents and cost reductions, this may change in the near future. Although the structure and function of the avian immune system show commonalities with mammals, at the molecular level, there is often low homology across species. The cross-reactivity of mammalian immunological reagents is therefore low, but nevertheless, the list of reagents to study chicken immune cells is increasing. Recent improvement in multicolor antibody panels for chicken cells has resulted in more detailed analysis by flow cytometry and has allowed the discovery of novel leukocyte cell subpopulations. In this article, we present an overview of the reagents and guidance needed to perform multicolor flow cytometry using chicken samples and common pitfalls to avoid.

Estimering af videns- og finansieringsbehov for opnåelse af klimamål i 2030

Olesen, J. E., Lund, P., Feilberg, A., et al. — Mon, 27 May 2024 04:38:58 +0200

Animal-based methods for the assessment of broiler chicken welfare in organic and conventional production systems

Rasmussen, S. N., Wurtz, K. E., Erasmus, M., Riber, A. B. — Mon, 01 Jul 2024 04:38:58 +0200

Animal welfare is one of the pillars in organic broiler production, evident in practices such as utilizing slower-growing hybrids and maintaining lower stocking densities for the birds. However, despite these efforts, skepticism and uncertainty remain regarding the extent to which animal welfare objectives are achieved in organic farming. The primary aim of this study was to compare animal-based measures assessing positive and negative welfare between organic and conventional broiler chickens in Denmark. The selected positive welfare indicators included Qualitative Behavior Assessment (QBA) and observations of play behavior in an open-space test. An additional aim of this study was to examine the reliability of the method by having all QBA observations done by two observers. Negative welfare indicators included walking ability assessed using the 6-point Bristol gait score method and fearfulness assessed using a novel object test. Welfare assessments were conducted on-farm before slaughter at 31–33 days of age for conventional birds and at 49–55 days of age for organic birds. The results from the QBA indicated differences between organic and conventional production systems (P = 0.001). Specifically, organic broilers exhibited higher levels of active, energetic, positively occupied, happy, and agitated behaviors. Notably, the outcome of the QBA was influenced by the observer (P = 0.001); on average, one observer tended to assign higher scores specifically for depressed and distressed behaviors, while the other observer allocated higher scores to the remaining behavioral terms. Moreover, organic broilers tended to show better walking abilities than conventional broilers (P = 0.064). Fear responses were similar across both production systems. Finally, organic broilers demonstrated a lower frequency of play behavior in open spaces compared to conventional broilers (P = 0.001). Conventional birds may have expressed more play behavior due to the greater contrast between the sudden availability of open space and their typical stocking density, resulting in increased compensatory play. This presents a challenge since a higher frequency of play is often considered an indicator of positive welfare, but we speculate whether in this study, it might suggest a restriction of spontaneous play due to space limitations caused by the high stocking density in the conventional production system. As a result, when additional space becomes available, it could lead to a rebound effect. Future research should explore how stocking density influences play behavior in broiler chickens, including measures of both spontaneous play and stimulated play during controlled test situations.

Implementation of the Use of the Enteric Methane Mitigating Feed Additive Bovaer® in the National Danish Emission Inventories for Dairy Cows

Lund, P., Maigaard, M., Kjeldsen, M. H., et al. — Mon, 10 Jun 2024 04:38:58 +0200

Vurdering af afkølingsmuligheder ved vand fremfor skygge for udegående kreaturer

Malmkvist, J., Jensen, M. B. — Fri, 31 May 2024 04:38:58 +0200

Feed intake in housed dairy cows

Giagnoni, G., Lassen, J., Lund, P., Foldager, L., Johansen, M., Weisbjerg, M. R. — Sat, 01 Jun 2024 04:38:58 +0200

Measuring feed intake accurately is crucial to determine feed efficiency and for genetic selection. A system using three-dimensional (3D) cameras and deep learning algorithms can measure the volume of feed intake in dairy cows, but for now, the system has not been validated for feed intake expressed as weight of feed. The aim of this study was to validate the weight of feed intake predicted from the 3D cameras with the actual measured weight. It was hypothesised that diet−specific coefficients are necessary for predicting changes in weight, that the relationship between weight and volume is curvilinear throughout the day, and that manually pushing the feed affects this relationship. Twenty-four lactating Danish Holstein cows were used in a cross-over design with four dietary treatments, 2 × 2 factorial arranged with either grass-clover silage or maize silage as silage factor, and barley or dried beet pulp as concentrate factor. Cows were adapted to the diets for 11 d, and for 3 d to tie-stall housing before camera measurements. Six cameras were used for recording, each mounted over an individual feeding platform equipped with a weight scale. When building the predictive models, four cameras were used for training, and the remaining two for testing the prediction of the models. The most accurate predictions were found for the average feed intake over a period when using the starting density of the feed pile, which resulted in the lowest errors, 6% when expressed as RMSE and 5% expressed as mean absolute error. A model including curvilinear effects of feed volume and the impact of manual feed pushing was used on a dataset including daily time points. When cross-validating, the inclusion of a curvilinear effect and a feed push effect did not improve the accuracy of the model for neither the feed pile nor the feed removed by the cow between consecutive time points. In conclusion, measuring daily feed intake from this 3D camera system in the present experimental setup could be accomplished with an acceptable error (below 8%), but the system should be improved for individual meal intake measurements if these measures were to be implemented.

FdeC expression regulates motility and adhesion of the avian pathogenic Escherichia coli strain IMT5155

Aleksandrowicz, A., Kjærup, R. B., Grzymajło, K., et al. — Wed, 01 May 2024 04:38:58 +0200

Adaptation of avian pathogenic E. coli (APEC) to changing host environments including virulence factors expression is vital for disease progression. FdeC is an autotransporter adhesin that plays a role in uropathogenic Escherichia coli (UPEC) adhesion to epithelial cells. Expression of fdeC is known to be regulated by environmental conditions in UPEC and Shiga toxin-producing E. coli (STEC). The observation in a previous study that an APEC strain IMT5155 in which the fdeC gene was disrupted by a transposon insertion resulted in elevated adhesion to chicken intestinal cells prompted us to further explore the role of fdeC in infection. We found that the fdeC gene prevalence and FdeC variant prevalence differed between APEC and nonpathogenic E. coli genomes. Expression of the fdeC gene was induced at host body temperature, an infection relevant condition. Disruption of fdeC resulted in greater adhesion to CHIC-8E11 cells and increased motility at 42 °C compared to wild type (WT) and higher expression of multiple transporter proteins that increased inorganic ion export. Increased motility may be related to increased inorganic ion export since this resulted in downregulation of YbjN, a protein known to supress motility. Inactivation of fdeC in APEC strain IMT5155 resulted in a weaker immune response in chickens compared to WT in experimental infections. Our findings suggest that FdeC is upregulated in the host and contributes to interactions with the host by down-modulating motility during colonization. A thorough understanding of the regulation and function of FdeC could provide novel insights into E. coli pathogenesis.

Effect of grinding or rolling fava beans on feed intake and milk production in Holstein cows

Rozada, T. d. E., Johansen, M., Weisbjerg, M. R., Larsen, M. — Mon, 01 Jul 2024 04:38:58 +0200

The objective of the present study was to evaluate the performance of primi- and multiparous dairy cows fed diets with ground or rolled fava beans (FB). A total of 96 Danish Holstein cows (48 primi- and 48 multiparous) were used in a randomized block design lasting 4 weeks. Within parity group, cows were blocked according to their milk yield in 6 blocks with 8 cows each and two cows from each block were distributed in pens where they were assigned randomly one of the two experimental diets. The diets were based on a total mix ration (TMR) composed of 52.6 % forage and 47.4 % concentrate (DM basis), differing only in the particle size of FB (geometric mean diameters of 1.02 and 3.52 mm for ground and rolled FB, respectively). Feed intake, milk production, and milk composition were determined during the last 8 days of the experimental period; none of these differed between treatments except for a higher (P = 0.01) milk N efficiency (% of N intake) and milk urea content with ground FB compared with rolled FB. Additionally, feces and ruminal fluid were collected from a group of 24 multiparous cows to determine fecal starch content and ruminal volatile fatty acids (VFAs). The fecal starch concentration was greater with rolled FB showing a reduced starch digestion, whereas ruminal VFA proportions generally did not differ between treatments. In conclusion, the lactation performance of dairy cows appeared not to be affected by grinding or rolling of FB with a 20 % FB inclusion in the DM diet, even though total tract starch digestion was reduced with greater FB particle size.

Effect of different feeding strategies and dietary fiber levels on energy and protein retention in gestating sows

Wisbech, S. J., Nielsen, T. S., Bach Knudsen, K. E., Theil, P. K., Bruun, T. S. — Mon, 01 Apr 2024 04:38:58 +0200

The aim of the study was to investigate whether increased inclusion of sugar beet pulp (SBP) alters retention of fat, protein, and energy when backfat (BF) is restored in early- and mid-gestation. In total, 46 sows were fed one of four dietary treatments with increasing inclusion of SBP providing dietary fiber (DF) levels of 119, 152, 185, and 217 g/kg; sows were assigned to one of three feeding strategies (FS; high, medium, and low) depending on BF thickness at mating and again at day 30 for the following month. On days 0, 30, 60, and 108, body weight (BW) and BF thickness were measured and body pools of protein and fat were estimated using the deuterium oxide technique. On days 30 and 60, urine, feces, and blood samples were collected to quantify metabolites, energy, and nitrogen (N) balances. On days 15 and 45, heart rate was recorded to estimate heat energy. At farrowing, total born and weight of the litter were recorded. In early gestation, BW gain (P < 0.01) and body protein retention increased (P < 0.05) with increasing fiber inclusion, while body fat retention increased numerically by 59%. The increase in BF was greatest for sows fed the high FS, intermediate when fed the medium strategy, and negligible for sows fed the lowest FS (P < 0.001). Nitrogen intake, N loss in feces, and N balance increased linearly, whereas N loss in urine tended to decrease with increasing inclusion of fibers in early gestation. Concomitantly, fecal energy output and energy lost as methane increased linearly (P < 0.001), while energy output in urine declined linearly. Total metabolizable energy (ME) intake therefore increased from 36.5 MJ ME/d in the low fiber group to 38.5 MJ ME/d in the high fiber group (P < 0.01). Changing the ME towards more ketogenic energy was expected to favor fat retention rather than protein retention. However, due to increased intake of ME and increased N efficiency with increasing fiber inclusion, the sows gained more weight and protein with increas¬ing fiber inclusion. In conclusion, increased feed intake improved both fat and protein retention, whereas increased DF intake increased protein retention.

Ulva species: A critical review on the green seaweed as a source of food protein

Juul, L., Nissen, S. H., Bruhn, A., et al. — Mon, 01 Jul 2024 04:38:58 +0200

Background: Green macroalgae of the Ulva genus have gained interest as a source of protein, due to the high production potential and high proportion of essential amino acids. This review gives an overview of Ulva protein, including extraction and evaluation of protein quality in terms of nutritional value, functionality, and sensory properties with preliminary suggestions to reach the market. Scope and approach: Available literature on protein extraction from Ulva was reviewed along with studies investigating the nutritional quality of Ulva protein and functional properties including aroma and flavor characteristics. Opportunities, challenges, and knowledge gaps are presented. Key findings and conclusion: A range of studies are investigating protein extraction, but only a few studies have dealt with protein digestibility, and food protein products. The digestibility of protein in crude Ulva biomass is low compared to conventional protein sources but increase with protein extraction. Sensory and functionality studies on Ulva protein are yet absent, but the whole biomass has been investigated, indicating the potential. The lack of consisting studies calls for more investigations related to food quality of Ulva protein. Upscaling and biorefinery models need to be explored to unfold the true potential of Ulva as a source of food protein.

Distribution of oxygen in marine sediments measured with microelectrodes

Revsbech, N. P., Sorensen, J., Blackburn, T. H., Lomholt, J. P. — Thu, 01 May 1980 04:38:58 +0200

This article is in Free Access Publication and may be downloaded using the “Download Full Text PDF” link at right.

Ecological Civilisation and Amphibian Sustainability through Reproduction Biotechnologies, Biobanking, and Conservation Breeding Programs (RBCs)

Browne, R. K., Luo, Q., Wang, P., et al. — Wed, 01 May 2024 04:38:58 +0200

Intergenerational justice entitles the maximum retention of Earth’s biodiversity. The 2022 United Nations COP 15, “Ecological Civilisation: Building a Shared Future for All Life on Earth”, is committed to protecting 30% of Earth’s terrestrial environments and, through COP 28, to mitigate the effects of the climate catastrophe on the biosphere. We focused this review on three core themes: the need and potential of reproduction biotechnologies, biobanks, and conservation breeding programs (RBCs) to satisfy sustainability goals; the technical state and current application of RBCs; and how to achieve the future potentials of RBCs in a rapidly evolving environmental and cultural landscape. RBCs include the hormonal stimulation of reproduction, the collection and storage of sperm and oocytes, and artificial fertilisation. Emerging technologies promise the perpetuation of species solely from biobanked biomaterials stored for perpetuity. Despite significant global declines and extinctions of amphibians, and predictions of a disastrous future for most biodiversity, practical support for amphibian RBCs remains limited mainly to a few limited projects in wealthy Western countries. We discuss the potential of amphibian RBCs to perpetuate amphibian diversity and prevent extinctions within multipolar geopolitical, cultural, and economic frameworks. We argue that a democratic, globally inclusive organisation is needed to focus RBCs on regions with the highest amphibian diversity. Prioritisation should include regional and international collaborations, community engagement, and support for RBC facilities ranging from zoos and other institutions to those of private carers. We tabulate a standard terminology for field programs associated with RBCs for publication and media consistency.

Svar på Spørgsmål til AU-ANIVET i forbindelse med KU-IFRO’ vurderinger af omkostningerne til metanreducerende fodringstiltag

Weisbjerg, M. R., Børsting, C. F., Lund, P. — Fri, 31 May 2024 04:38:58 +0200

Hemizygous minipigs produced by random gene insertion and handmade cloning express the Alzheimer's disease-causing dominant mutation APPsw

Kragh, P. M., Nielsen, A. L., Li, J., et al. — Sat, 01 Aug 2009 04:38:58 +0200

In an effort to develop a porcine model of Alzheimer's disease we used handmade cloning to produce seven transgenic Göttingen minipigs. The donor fibroblasts had been stably transfected with a plasmid cassette containing, as transgene, the cDNA of the neuronal variant of the human amyloid precursor protein gene with the Swedish mutation preceded by beta-globin sequences to induce splicing and a human PDGF beta promoter fragment to drive transcription. Transgene insertion had occurred only at the GLIS3 locus where a single complete copy of the transgene was identified in intronic sequences in opposite direction. Similar and robust levels of the transgene transcript were detected in skin biopsies from all piglets and the sequence of full-length transcript was verified. Consistent with PDGF beta promoter function, high levels of transgene expression, including high level of the corresponding protein, was observed in brain tissue and not in heart or liver tissues. A rough estimate predicts that accumulation of the A beta peptide in the brain may develop at the age of 1-2 years.

Salmonella overlever længe i sand

Thomsen, P. T. — Wed, 01 May 2024 04:38:58 +0200

Key determinants of adaptive strategies of goats to a 2-day nutritional challenge during early lactation

Gindri, M., Friggens, N. C., Dhumez, O., et al. — Sat, 01 Jun 2024 04:38:58 +0200

Little is known about the key determinants of the physiological adaptations to environmental challenges and how these determinants interact. We evaluated how the response/recovery profiles to a short-term nutritional challenge during early lactation are affected by early-life nutritional strategies in dairy goats divergently selected for functional longevity. We used 72 females, split into two cohorts, daughters of Alpine bucks divergently selected for functional longevity. The females from the two lines were fed with two divergent diets, normal vs low-energy, from weaning until the middle of first gestation, and then fed with the same standard diet. Individual BW, body condition score, morphology, and plasma samples were collected from birth to first kidding. The adaptative physiological strategy to a nutritional challenge was assessed via a 2-day feed restriction challenge, during early lactation, which consisted of a five-day control period on a standard lactation diet followed by a 2-day challenge with straw-only feeding and then a 10-day recovery period on a standard lactation diet. During the challenge, DM intake, BW, milk yield (MY), and plasma and milk metabolite composition were recorded daily. Linear mixed-effects models were used to analyze all traits, considering the individual nested in the cohort as a random effect and the 2 × 2 treatments (i.e., line and rearing diet) and litter size as fixed effects. Linear mixed-effects models using a piecewise arrangement were used to analyze the response/recovery profiles to nutritional challenge. Random parameters estimated for each individual, using the mixed-effects models without the fixed effects of rearing diet and genetic line, were used in a stepwise model selection based on R² to identify key determinants of an individual's physiological adaptations to environmental challenges. Differences in stature and body reserves created by the two rearing diets diminished during late gestation and the 5-day control period. Genetic line did not affect body reserves during the rearing phase. Rearing diet and genetic line slightly affected the recovery profiles of evaluated traits and had no effects on prechallenge and response to challenge profiles. The prekidding energy status measures and MY before challenge were selected as strong predictors of variability in response-recovery profiles of milk metabolites that have strong links with body energy dynamics (i.e., isoCitrate, ß-hydroxybutyrate, choline, cholesterol, and triacylglycerols; R² = 35%). Our results suggested that prekidding energy status and MY are key determinants of adult resilience and that rearing diet and genetic line may affect adult resilience insofar as they affect the animals’ energy status.

Dark brooder pullets are less active than Non-brooder pullets, but show similar level of synchronisation at the resource areas

Martin-Cicera, A., Lyrakis, M., Riber, A. B., et al. — Sat, 01 Jun 2024 04:38:58 +0200

Maternal care in commercial chickens can partially be replaced with dark brooders that offer heat and a dark area to rest and possibly avoid negative social interactions. Previous research has established the positive effects of dark brooders on reducing disturbance during resting in young pullets and injurious pecking in pullets and laying hens, which could reduce overall activity levels. The objective of this study was to employ precision livestock farming techniques to compare the overall activity levels and behavioural synchrony at resources in pullets reared with dark brooders until 41 days of age and those reared with whole house heating. Four brooder treatments, varying in size (Small/Large) and deployment method (Raised/Fixed), which could have implications for commercial use, were employed. Activity of the whole pen floor area and behavioural synchrony in drinker and feeder areas were automatically assessed over a 12-hour photoperiod at 10 and 60 days of age. Pixel change detection gauged overall activity across the pen, while an object detection model evaluated pullet behavioural synchrony. The analysis revealed increased activity levels in non-Brooder pullets compared to those in most Brooder treatments at both 10 and 60 days of age. However, no significant differences in behavioural synchrony were observed between Brooder and non-Brooder pullets. The underlying mechanism of dark brooder's effects on the activity levels and behaviour synchrony remains unclear, but the observed reduction in activity levels in brooded pullets likely corresponds to increased resting behaviour and reduced injurious pecking. Furthermore, it is noteworthy that only a small percentage of pullets (up to 57.14%) were observed to use the resources simultaneously. This underscores the importance of conducting additional research to delve into the effects of resource allocation on both behavioural synchrony and activity levels in pullets. We observed minimal differences in the behaviour of pullets raised under different brooder types, suggesting that the simplest (Small-Fixed) brooders may be suitable for commercial use.