M B M Maidin, H A McCormack, P W Wilson, I J Liang, B Andersson, M Schmutz, I C Dunn
{"title":"Association of keel bone morphometry with keel bone damage and skeletal quality in the laying hen.","authors":"M B M Maidin, H A McCormack, P W Wilson, I J Liang, B Andersson, M Schmutz, I C Dunn","doi":"10.1080/00071668.2024.2409191","DOIUrl":"https://doi.org/10.1080/00071668.2024.2409191","url":null,"abstract":"<p><p>1. The aim of this work was to identify a heritable keel bone phenotype with a correlation to keel bone damage and/or skeletal bone strength that could be easily measured in the living hen to aid selection to prevent welfare issues.2. The scoring system used reflected the observed damage, keel bone dimensions and shape compared to traditional measurements of bone quality.3. Increased keel bone damage was associated with poor humerus and tibia breaking strengths (<i>p</i> < 0.01). Bone damage was associated with higher whole keel density (<i>p</i> < 0.01) due to the effect of callus formation.4. Keel bone depth and area was moderately heritable at indices of 0.32 and 0.40, respectively. Keel bone depth was genetically correlated with tibia (0.36) and humerus density (0.68) and keel bone area was correlated with humerus density (0.59). Deeper keel bones and those with larger areas had small, negative phenotypic correlations with keel bone damage (-0.07 and -0.11, respectively). The second principal component of keel bone shape represented the caudal section of the keel bone and cranial edge concavity. The third principal component represented the differences in the caudal tip of the keel bone, the concavity of the dorsal edge and convexity of the ventral edge. Heritability estimates were 0.44 and 0.39, respectively.5. The results suggested that genetics contribute to morphometric traits. Hens with poorer skeletal quality are likely to accumulate more damage. Some of the traits may be a predictor of damage, although mid keel depth or concavity may simply reflect the effect of damage or deviation.</p>","PeriodicalId":9322,"journal":{"name":"British Poultry Science","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142495552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T Shynkaruk, M Parsons, C A B Adler, C Goeree, K Long, K Schwean-Lardner
{"title":"Does the distribution of light intensity within the barn impact broiler production and welfare?","authors":"T Shynkaruk, M Parsons, C A B Adler, C Goeree, K Long, K Schwean-Lardner","doi":"10.1080/00071668.2024.2414460","DOIUrl":"https://doi.org/10.1080/00071668.2024.2414460","url":null,"abstract":"<p><p>1. The objective of this study was to determine if rearing broilers under variable light intensity (VLI) impacted their welfare or productivity.2. Ross 308 broilers (<i>n</i> = 7,256) were reared until 35 d of age and exposed to a uniform intensity of 10 lux (CON) or VLI with low intensity areas of 2-5 lux proximal to the walls and high intensity areas of 84-133 lux proximal to feeders.3. The data were analysed as a complete randomised design using an analysis of variance. Significance was declared when <i>p</i> ≤ 0.05.4. Applying VLI resulted in increased feed intake early in life but had no impact on body weight. Overall efficiency was improved in the CON treatment. Mortality diagnoses of skeletal problems were reduced under VLI. Treatment had no impact on footpad, hock or gait score, heterophil to lymphocyte ratio or melatonin concentration. Birds performed certain behaviours in specific locations within the room, independent of light intensity treatment.5. In conclusion, raising broilers under VLI had little impact on production or most welfare parameters assessed in this study. However, satisfying the bird's preference for different light intensities may improve welfare.</p>","PeriodicalId":9322,"journal":{"name":"British Poultry Science","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142495555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effects of calcium pidolate on performance, carcass traits, bone biomechanical properties and mineralisation and jejunum histomorphology in broilers.","authors":"E T Gül","doi":"10.1080/00071668.2024.2410366","DOIUrl":"https://doi.org/10.1080/00071668.2024.2410366","url":null,"abstract":"<p><p>1. The current study was conducted to determine the effect of dietary calcium pidolate (CalP) on performance, slaughtering characteristics, bone biomechanical properties, mineralisation and jejunum histomorphology in male broilers. A total of 200 one-day-old Ross 308 male chicks were randomly assigned to one of four treatments as five pen replicates, each containing 10 chicks. The basal diet without CalP was formulated to supply the nutritional needs of broilers and the treatment diets contained 0.30, 0.45 and 0.60 g/kg CalP, with limestone meeting the remaining calcium requirement.2. The addition of CalP had a quadratic effect on performance (P < 0.05) and the best performance was achieved in the group that included CalP at a dose of 0.45 g/kg but 0.60 g/kg level worsened performance. Supplementing with CalP linearly decreased carcass yield (P < 0.01) and relative breast weight (P ≤ 0.05) but the relative thigh weight increased quadratically (P < 0.05) and reached a maximum at 0.45 g/kg.3. Tibia shear force and stress linearly increased with the use of CalP in the diet (P < 0.05). Supplementation had a quadratic effect on tibial calcium (P < 0.01), reaching a maximum at 0.30 g/kg, although tibial phosphorus levels decreased linearly (P < 0.01).4. The effect of CalP on jejunum histomorphology fluctuated and, compared to the unsupplemented control group, the villus height/crypt depth ratio increased, while the other variables decreased (P < 0.05). Decrease in crypt depth with the addition of CalP was significant (P < 0.05).5. Using Ca-pidolate at a rate of 0.45 g/kg in broiler diets is sufficient to increase performance and tibia strength but 0.60 g/kg level negatively affected performance. In addition, the results of jejunum histomorphology were variable, but the crypt depth decreased with CalP levels and this is an important effect. However, further research is needed to detail the effect of CalP on broilers.</p>","PeriodicalId":9322,"journal":{"name":"British Poultry Science","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142495556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S Wang, Y Liu, S Liu, Z Qin, J Lu, R Zhang, H Yuan
{"title":"Consensus gene co-expression analysis across multiple intestinal tissues to identify key genes and pathways associated with abdominal fat deposition in broilers.","authors":"S Wang, Y Liu, S Liu, Z Qin, J Lu, R Zhang, H Yuan","doi":"10.1080/00071668.2024.2410367","DOIUrl":"https://doi.org/10.1080/00071668.2024.2410367","url":null,"abstract":"<p><p>1. Abdominal fat deposition (AFD) is regulated by multiple intestinal tissues, and changes in the function of intestinal tissues are associated with AFD. Currently, integration of transcriptomic data across multiple intestinal tissues to explore excessive AFD has rarely been reported in broilers.2. In this study, a consensus gene co-expression network across the duodenum, jejunum, ileum and caecum of high- and low-abdominal fat broiler lines (HL and LL) was constructed using a publicly available transcriptomic data set. Combining the results of functional enrichment analyses and differential gene expression analyses, this investigated the genes and biological pathways across the four intestinal tissues that might influence AFD.3. In one expression module, <i>NDUFA5</i>, <i>NDUFS6</i>, <i>NDUFA4</i>, <i>NDUFS4</i>, <i>ATP5H</i>, <i>ATP5J</i> and <i>ATP5C1</i> were significantly enriched in the oxidative phosphorylation pathway, with <i>GPX2</i> and <i>GSR</i> significantly enriched in the glutathione metabolism pathway. These genes were significantly downregulated in the four intestinal tissues of the HL compared to LL chickens, which may be associated with AFD by increasing intestinal permeability.4. Lipid metabolism relevant genes were identified in other modules (<i>ALDH7A1</i>, <i>ACSBG1</i>, <i>THEM4</i> and <i>DECR1</i>), which may be linked to AFD through regulation of lipid metabolism. Interestingly, in the first module, 12 genes were significantly enriched in the proteasome pathway and significantly downregulated in the four intestinal tissues in HL birds compared to LL birds, indicating a link between the proteasome and AFD.</p>","PeriodicalId":9322,"journal":{"name":"British Poultry Science","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142495553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
I Kyriazakis, S Dokou, J Taylor, I Giannenas, E Murphy
{"title":"A meta-analysis of the sources of variation in the environmental impacts of different broiler production systems.","authors":"I Kyriazakis, S Dokou, J Taylor, I Giannenas, E Murphy","doi":"10.1080/00071668.2024.2409192","DOIUrl":"https://doi.org/10.1080/00071668.2024.2409192","url":null,"abstract":"<p><p>1. Shifting to higher welfare systems is expected to increase their environmental impact and mitigation strategies need to be identified. The environmental impacts associated with various broiler production systems (BPS: conventional, higher welfare indoors, free-range or organic) and the characteristics of BPS which contribute to these impacts were investigated via a literature review and meta-analysis.2. The impact metrics considered were global warming (GWP), acidification and eutrophication potentials, NH<sub>3</sub> emissions, land use, water use, energy use (EU) and biodiversity. Due to the paucity of data, analysis was limited to the impacts of the characteristics of the BPS: stocking density (STD), slaughter weight (SW), feed conversion ratio (FCR), on GWP, NH<sub>3</sub> emissions and EU.3. After correction for system boundaries and functional units, no statistical effects of BPS on GWP were found, while higher welfare systems were associated with higher EU. Reduced STD was associated with reductions in GWP and EU. The SW was positively associated with GWP and NH<sub>3</sub> emissions, while higher FCR was associated with increased NH<sub>3</sub> emissions and EU.4. Environmental impacts arose from feed-associated activities (>75%). Most of the GWP impacts were associated with land use change (LUC), especially when associated with 'unsustainable' soya. High variation in values for different environmental metrics within BPS indicated a lack of standardisation in the assessment of environmental impact across the industry.5. The results suggested that practices within a system contributed greatly to the environmental impact of the system. Rather than comparing systems, it may be more productive to focus on improving practices that have the potential to reduce environmental impacts within a system, without compromising animal welfare.</p>","PeriodicalId":9322,"journal":{"name":"British Poultry Science","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142495551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
V R Pirgozliev, K Kljak, I M Whiting, S C Mansbridge, A G Atanasov, S B Enchev, M Tukša, S P Rose
{"title":"Dietary stinging nettle (<i>Urtica dioica</i>) improves carotenoids content in laying hen egg yolk.","authors":"V R Pirgozliev, K Kljak, I M Whiting, S C Mansbridge, A G Atanasov, S B Enchev, M Tukša, S P Rose","doi":"10.1080/00071668.2024.2406335","DOIUrl":"https://doi.org/10.1080/00071668.2024.2406335","url":null,"abstract":"<p><p>1. This study assessed the addition of dried stinging nettle (SN) leaves at 0%, 2.5% and 5.0% in feed on egg production, egg quality, chemical composition and antioxidant content in eggs from laying hens.2. Seventy-two Hy-Line Brown laying hens, housed in 36 enriched layer cages, were used in the study from 43 to 47 weeks of age. Feeding dry SN leaves did not affect (<i>p</i> > 0.05) egg production variables.3. Dietary SN inclusion linearly increased (<i>p</i> < 0.001) carotenoid content more than six-fold, in addition to yellowness and redness of the yolks at the maximum inclusion. Providing eggs from hens fed carotenoid enriched diets, <i>e.g</i>. SN, may be used to increase carotenoids in human diets.</p>","PeriodicalId":9322,"journal":{"name":"British Poultry Science","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142495554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T Nakanishi, T Uchiyama, M Uchida, L Erickson, S Kawahara
{"title":"<i>Ante-mortem</i> glutathione peroxidase 4 inhibition by RSL3 affects post-mortem meat quality in broiler chickens.","authors":"T Nakanishi, T Uchiyama, M Uchida, L Erickson, S Kawahara","doi":"10.1080/00071668.2024.2412167","DOIUrl":"https://doi.org/10.1080/00071668.2024.2412167","url":null,"abstract":"<p><p>1. This study investigated the role of glutathione peroxidase 4 (GPX4), a key regulator of ferroptosis, a form of programmed cell death, in muscle biochemistry and meat quality, utilising broiler chickens whose <i>ante-mortem</i> GPX4 activity was inhibited pharmacologically.2. Male broilers were divided into two groups, each receiving <i>ante-mortem</i> administration of the GPX4 inhibitor, Ras-selective lethal 3 (RSL3), or a vehicle only. After slaughter, breast muscles were collected and stored for 48 h. The expressions of ferroptosis-related genes, glutathione levels, pH, colour and water-holding capacity were evaluated at multiple time points during the storage period.3. The RSL3 treatment decreased the expression of <i>GPX4</i> and ferritin heavy chain 1, which are negative regulators of ferroptosis, while it increased the expression of a ferroptosis accelerator, acyl-CoA synthetase long chain family member 4. The ratio of reduced to oxidised glutathione was significantly decreased in the RSL3 group. The RSL3 treatment decelerated post-mortem pH decline and colour changes, such as a decrease in L* and an increase in a* were observed in the RSL3 group. In addition, the RSL3 group showed increased levels of water-holding capacity.4. These findings suggested that <i>ante-mortem</i> GPX4 activity plays a role in determining meat quality, implying the possible involvement of ferroptosis in the mechanism by which skeletal muscle is converted after slaughter into meat that is eaten.</p>","PeriodicalId":9322,"journal":{"name":"British Poultry Science","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142495550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D Durna Corum, O Corum, K Uney, E Turk, F Sakin, M Giorgi
{"title":"Pharmacokinetics of tolfenamic acid in ducks (<i>Anas platyrhynchos domestica</i>) after different administration routes.","authors":"D Durna Corum, O Corum, K Uney, E Turk, F Sakin, M Giorgi","doi":"10.1080/00071668.2024.2410365","DOIUrl":"https://doi.org/10.1080/00071668.2024.2410365","url":null,"abstract":"<p><p>1. The objective of this research was to compare the pharmacokinetics and bioavailability of tolfenamic acid, analgesic, antipyretic and anti-inflammatory compound, after administration through different routes to Pekin ducks. The investigation was carried out over four time periods using a randomised cross-pharmacokinetic design.2. Tolfenamic acid was administered to ducks intravenously, intramuscularly, subcutaneously and orally at a dose of 2 mg/kg. Tolfenamic acid analysis was performed using HPLC-UV and pharmacokinetic data were conducted by non-compartmental analysis.3. The total clearance, volume of distribution at steady state and terminal elimination half-life after intravenous administration were 0.14 l/h/kg, 0.29 l/kg and 1.80 h, respectively. The peak plasma concentration and bioavailability for intramuscular, subcutaneous and oral administration were 4.59, 3.55 and 2.23 μg/ml and 93.62, 74.30 and 43.43%, respectively.4. Tolfenamic acid was absorbed rapidly, eliminated quickly and exhibited a small distribution volume in Pekin ducks. Pharmacokinetic parameters, including maximum concentration, area under the plasma concentration - time curve and bioavailability, were found to be different in ducks from other bird species.</p>","PeriodicalId":9322,"journal":{"name":"British Poultry Science","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142495557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S Wolfrum, W Siegert, I Rubio-Cervantes, D Feuerstein, A Camarinha-Silva, M Rodehutscord
{"title":"Effects of feed particle size, calcium concentration and phytase supplementation on InsP<sub>6</sub> degradation in broiler chickens fed pelleted diets.","authors":"S Wolfrum, W Siegert, I Rubio-Cervantes, D Feuerstein, A Camarinha-Silva, M Rodehutscord","doi":"10.1080/00071668.2024.2412096","DOIUrl":"https://doi.org/10.1080/00071668.2024.2412096","url":null,"abstract":"<p><p>1. The objective of the trial was to study the single and interactive effects of feed particle size in pelleted feed, dietary calcium (Ca) concentration and microbial phytase supplementation in broiler chickens. The studied traits were <i>myo</i>-inositol (1,2,3,4,5,6) hexakis (dihydrogen phosphate) (InsP<sub>6</sub>) degradation, pre-caecal digestibility of phosphorus (P), Ca and amino acids (AA) and retention of P, Ca and nitrogen (N).2. Male Ross 308 broiler chickens were housed in metabolism units in groups of 10 and allocated to one of eight diets with seven pen replicates per diet. The 2 × 2 × 2-factorial arrangement included coarse and fine feed particle size (309 or 222 µm), low and high Ca concentration (4.9 and 7.2 g/kg) and without or with phytase supplementation (1,000 FTU/kg).3. Pre-caecal InsP<sub>6</sub> disappearance was higher with coarse than fine feed particle size when no phytase was added (54 vs. 48%) but not when phytase was added (74%; <i>p</i> = 0.046). High dietary Ca feeds decreased pre-caecal InsP<sub>6</sub> disappearance (67 to 59%) and P digestibility (65 to 55%; <i>p</i> < 0.001). Gizzard pH was lower with coarse than fine feed particle size and higher with high Ca than low Ca (<i>p</i> < 0.001). Pre-caecal digestibility of most AA was approximately 3.5%-points lower with high Ca without phytase compared to the other treatments (<i>p</i> ≤ 0.047). Coarse feed particle size caused higher pre-caecal AA digestibility than fine particle size (~2%-points; <i>p</i> ≤ 0.031). InsP<sub>6</sub> disappearance in the crop increased at high Ca concentration when phytase was added (22 vs. 37%; <i>p</i> = 0.011).4. Coarser feed particle size in pellets increased gastrointestinal InsP<sub>6</sub> degradation and nutrient digestibility, likely owing to effects on the gizzard functions. Additional Ca supply exerted antinutritive effects that was not compensated for by using coarser feed particles.</p>","PeriodicalId":9322,"journal":{"name":"British Poultry Science","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142458548","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Tissue oxidative stress and expression of chicken UCP and ANT mRNA in laying hens exposed to acute cold stress.","authors":"L-Y Chang, L-X Dong, Z-Y Liu, E-Y Hao, X-Y Wang, L-Y Zhu, C-H Li, X-L Zhang","doi":"10.1080/00071668.2024.2406330","DOIUrl":"https://doi.org/10.1080/00071668.2024.2406330","url":null,"abstract":"<p><p>1. Exposure to stress alters normal homoeostasis and, hence, the antioxidant defence system. The aim of this study was to examine the effect of acute cold temperature on the antioxidant defence system in hens.2. Hy-line grey commercial layers (80 40-week-old) were randomly assigned to one of eight groups. In groups 1 to 5, hens were exposed to low temperature at -8.68°C (cool stressed) for 2, 4, 6, 8 and 10 h, respectively. In groups 6 and 7, post 10 h cool stressed, hens were quickly transferred to room at 21°C to recovery for 2 h and 4h, respectively. In treatment groups 6 and 7, post 10 h cool stressed, hens were quickly transferred to room at 21°C for 2 h and 4 h, respectively. Group 8 was the control, where hens were housed under regular condition at 21°C as controls.3. Antioxidant enzymes (T-AOC), superoxide dismutase (SOD), glutathione peroxidase (GPx) and malondialdehyde (MDA), in skeletal muscle, the kidney, liver and pancreas were measured. The transcription of avUCP and ANT mRNA was tested by RT-PCR.4. The T-AOC activity was increased in the skeletal muscle of hens cold stressed for 2, 4, 6, 8 and 10 h and the 2 h recovery groups compared with control hens (<i>p</i> < 0.05). The GPx activity was increased in the liver and skeletal muscle after cold stress 4 h and in the pancreas of cold stress 2 h compared with the control group (<i>p</i> < 0.05). Antioxidant SOD activity was increased in the kidney after cold stress 6 h and in the liver after cold stress 10 h compared to the control group (<i>p</i> < 0.05). Measured MDA activity was increased in the pancreas after 2 h cold stress (<i>p</i> < 0.05).5. UCP mRNA expression level was increased in the pectoral muscle for 2 h and 4 h recovery groups compared with the control hens (<i>p</i> < 0.05) and avian uncoupling protein (UPC), adenine nucleotide translocator (ANT) expression level was increased in the leg muscle of hens cold stress for 2, 6, 8 h and recovery 2 and 4 h.6. The observed changes in the antioxidant defence system were tissue specific. Increments in levels of ANT (leg muscle) and UCP (pectoral and leg muscle) mRNA expression may be involved in the regulation of thermogenesis in skeletal muscle.</p>","PeriodicalId":9322,"journal":{"name":"British Poultry Science","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142458550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}