Template-Type: ReDIF-Article 1.0 Author-Name: Magdaléna Štolcová Author-Name: Dalibor Řehák Author-Workplace-Name: Department of Cattle Breeding, Institute of Animal Science, Prague, Czech Republic Author-Name: Luděk Bartoň Author-Workplace-Name: Department of Cattle Breeding, Institute of Animal Science, Prague, Czech Republic Title: Changes in milk ketone and fatty acid concentrations during early lactation in Holstein and Fleckvieh cows Abstract: The aim of this study was to compare the changes in milk composition postpartum, especially ketones and milk fatty acids (FAs), in Holstein and Fleckvieh cows kept under identical management conditions. Milk composite samples were collected from 66 cows during afternoon milking, at weekly intervals from one to eight weeks postpartum, and their components were determined by Fourier transform infrared spectroscopy. The Holstein cows had higher (P < 0.05) concentrations of long-chain FAs (ranging from 6% to 16% in different weeks), monounsaturated FAs (6% to 12%), and C18:1 (5% to 16%), as well as lower (P < 0.05) concentrations of saturated FAs (3% to 8%) and short-chain FAs (7% to 17%) in their milk than the Fleckvieh cows for almost the entire monitored period. These differences can be explained by pronounced lipomobilization, due to a negative energy balance, when mainly long-chain FAs from adipose tissue are incorporated into milk and significantly inhibit the de novo synthesis of FAs in the mammary gland. In conclusion, it can be assumed that breed-related metabolic changes during the first weeks of lactation have a large effect on the milk FA composition. This reflection of the metabolic load changes and lipomobilization in differing milk FA profiles would allow for the use of selected milk FAs to detect energy imbalances and their associated diseases in early lactation cows. Keywords: breed, dairy cattle, periparturient period, milk fatty acids, milk ketones, Fourier transform infrared spectroscopy Journal: Czech Journal of Animal Science Pages: 477-486 Volume: 66 Issue: 12 Year: 2021 DOI: 10.17221/122/2021-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/122/2021-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-202112-0001.txt Handle: RePEc:caa:jnlcjs:v:66:y:2021:i:12:id:122-2021-CJAS Template-Type: ReDIF-Article 1.0 Author-Name: Eva Strapáková Author-Workplace-Name: Department of Genetics and Animal Breeding Biology, Faculty of Agrobiology and Food Resources, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: Peter Strapák Author-Workplace-Name: Department of Animal Husbandry, Faculty of Agrobiology and Food Resources, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: Juraj Candrák Author-Workplace-Name: Department of Genetics and Animal Breeding Biology, Faculty of Agrobiology and Food Resources, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: Ivan Pavlík Author-Workplace-Name: Slovak Simmental Cattle Breeders Association, Levice, Slovak Republic Author-Name: Katarína Dočkalová Author-Workplace-Name: BT installation s.r.o., Močenok, Slovak Republic Title: Fleckscore system of exterior evaluation as a more accurate indirect predictor of longevity in Slovak Simmental dairy cows Abstract: The goal of the work was to discover the influence of conformation traits evaluated by the Fleckscore system on the length of productive life of Slovak Simmental dairy cows. Evaluation of body conformation traits according to the Fleckscore system was performed on 3 452 cows. The relationship of individual traits to longevity was analysed using the Weibull proportional hazard model. The results confirmed that smaller and longer cows, which were well muscular and with a deeper body, had a lower risk of early culling than cows in the reference group. Hock angularity, pastern and hoof height scored with low or high marks were associated with an early culling of cows. In terms of the length of productive life, a slightly more elastic pattern is required. Cows with a deeper udder and a stronger and tighter fore udder attachment, which were also average in notching and height central ligament and centrally placed teats, reached a longer productive life. Keywords: conformation traits, cattle, length of productive life, survival analysis, Weibull model Journal: Czech Journal of Animal Science Pages: 487-494 Volume: 66 Issue: 12 Year: 2021 DOI: 10.17221/102/2021-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/102/2021-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-202112-0002.txt Handle: RePEc:caa:jnlcjs:v:66:y:2021:i:12:id:102-2021-CJAS Template-Type: ReDIF-Article 1.0 Author-Name: Tsukasa Yoshidomi Author-Workplace-Name: School of Veterinary Medicine, Azabu University, Sagamihara, Japan Author-Name: Kazuaki Tanaka Author-Workplace-Name: School of Veterinary Medicine, Azabu University, Sagamihara, Japan Author-Workplace-Name: Center for Human and Animal Symbiosis Science, Azabu University, Sagamihara, Japan Author-Name: Tatsuya Takizawa Author-Workplace-Name: School of Veterinary Medicine, Azabu University, Sagamihara, Japan Author-Name: Satoshi Nikaido Author-Workplace-Name: ZEN-NOH Livestock Co., Ltd., Tokyo, Japan Author-Name: Tetsuya Ito Author-Workplace-Name: Central Research Institute for Feed and Livestock, ZEN-NOH, Kato-gun, Japan Author-Name: Mai Kamikawa Author-Workplace-Name: Central Research Institute for Feed and Livestock, ZEN-NOH, Kato-gun, Japan Author-Name: Kensuke Hirose Author-Workplace-Name: Central Research Institute for Feed and Livestock, ZEN-NOH, Kato-gun, Japan Title: Copy number variation of amylase alpha 2B gene is associated with feed efficiency traits in Large White pigs Abstract: Copy number variation (CNV) of the AMY gene in humans has been enthusiastically studied for its association with starch digestibility and obesity. The alpha-amylase (AMY) is a major starch digestive enzyme in mammals. This study aimed to determine the association between CNV of the porcine pancreatic amylase (AMY2B) gene and feed efficiency. Improvement of feed efficiency in growing pigs is of great economic interest. We assayed the copy number of AMY2B by using real-time quantitative PCR (qPCR) in a Large White pig population. We identified three genotypes for AMY2B CNVs, namely I/I (homozygotes of haplotype I; a chromosome with one copy of AMY2B), I/II (heterozygotes of haplotype I and II; a chromosome with two copies) and II/II (homozygotes of haplotype II). We tested the genotypes of the parental generation consisting of six males, 21 females and 265 offspring piglets to validate the AMY2B CNV genotyping. With very few mistyping exceptions, copy numbers of AMY2B were transmitted to piglets in segregation ratios following Mendelian inheritance. Finally, we performed an association analysis between the CNV of the AMY2B gene and feed efficiency traits in 207 uncastrated male pigs. The generalised linear model analysis showed the significant effects of AMY2B CNV genotype on average daily feed intake, total feed intake and feed conversion ratio during growth from 30 kg to 100 kg body weight. However, it was not associated with average daily gain, backfat thickness and loin eye muscle area. Individuals with the genotype I/I had about 76.6 ± 27.1 g lower average daily feed intake, 5.35 ± 1.90 kg lower total feed intake and 0.089 8 ± 0.026 5 lower feed conversion ratio than individuals with I/II and II/II genotypes. Thus, AMY2B CNV has the potential to be an effective genetic marker that could reduce feed costs for pig farming. Keywords: feed intake, gene duplication, genetic analysis, quantitative trait locus, pig breeding Journal: Czech Journal of Animal Science Pages: 495-503 Volume: 66 Issue: 12 Year: 2021 DOI: 10.17221/117/2021-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/117/2021-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-202112-0003.txt Handle: RePEc:caa:jnlcjs:v:66:y:2021:i:12:id:117-2021-CJAS Template-Type: ReDIF-Article 1.0 Author-Name: Xiuling Li Author-Workplace-Name: School of Life Sciences, Linyi University, Linyi, P.R. China Author-Name: Yujie Zhang Author-Workplace-Name: School of Life Sciences, Linyi University, Linyi, P.R. China Author-Name: Wenqian Jing Author-Workplace-Name: School of Agriculture and Forestry Sciences, Linyi University, Linyi, P.R. China Author-Name: Weiqi Tang Author-Workplace-Name: College of Animal Sciences and Technology, Sichuan Agricultural University, Chengdu, P.R. China Author-Name: Jinyi Xing Author-Workplace-Name: School of Life Sciences, Linyi University, Linyi, P.R. China Author-Name: Yunyun Zhang Author-Workplace-Name: School of Life Sciences, Linyi University, Linyi, P.R. China Title: Effects of folic acid supplementation to basal diets of broilers on growth performance, slaughter performance, IGF2 gene expression and methylation Abstract: Folic acid (FA) is an important water-soluble vitamin and plays an important role as a cofactor and coenzyme in animal growth and development, and regulation of gene expression and methylation. A total of 270 female broiler chickens (1-day-old) were randomly allotted to three dietary treatments supplemented with 0 mg/kg (control group), 5 mg/kg, and 10 mg/kg FA in basal diets for 42 days, respectively. Each treatment had six replicate cages with 15 birds per cage. Dietary supplementation of 5 mg/kg FA significantly enhanced average body weight and average daily gain of 21-day-old broilers (P < 0.05), but significantly reduced subcutaneous fat thickness and widths of an intermuscular fat band of 42-day-old broilers by dietary FA treatments (P < 0.05). Also, a diet with 10 mg/kg FA supplementation significantly increased the relative heart weight of 42-day-old chickens (P < 0.05). Furthermore, dietary FA supplementation significantly improved the serum insulin-like growth factor 2 (IGF2) concentrations (P < 0.01) and IGF2 mRNA expression in the abdominal fat (P < 0.05), but no statistical differences were found in the methylation of IGF2 promoter (P > 0.05). The present study demonstrated that dietary FA supplementation may have positive effects on chicken growth through increased IGF2 gene expression. Keywords: chicken, fat, folate, growth traits, gene regulation Journal: Czech Journal of Animal Science Pages: 504-512 Volume: 66 Issue: 12 Year: 2021 DOI: 10.17221/76/2021-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/76/2021-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-202112-0004.txt Handle: RePEc:caa:jnlcjs:v:66:y:2021:i:12:id:76-2021-CJAS