Template-Type: ReDIF-Article 1.0 Author-Name: Michaela Černá Author-Workplace-Name: Department of Genetics and Breeding of Farm Animals, Institute of Animal Science, Prague-Uhříněves, Czech Republic Author-Name: Milan Margetín Author-Workplace-Name: Institute of Animal Husbandry, Faculty of Agrobiology and Food Resources, Slovak Agricultural University in Nitra, Nitra, Slovak Republic Author-Name: Zdeňka Veselá Author-Workplace-Name: Department of Genetics and Breeding of Farm Animals, Institute of Animal Science, Prague-Uhříněves, Czech Republic Author-Name: Michal Milerski Author-Workplace-Name: Department of Genetics and Breeding of Farm Animals, Institute of Animal Science, Prague-Uhříněves, Czech Republic Title: Effects of crossbreeding on milk production of sheep Abstract: The aim of this study was to estimate the effects of crossbreeding on milk production and milk components in crossbred Tsigai, Lacaune, and Improved Wallachian sheep used to create a synthetic Slovak dairy sheep population. The local breeds Tsigai and Improved Wallachian were crossed with the high-yielding breed Lacaune to increase milk yield. The effects of crossbreeding were evaluated based on breed and heterosis effects. The database used consisted of 23 018 lactations from 15 888 ewes. The effects of crossbreeding on milk production and fat and protein content were estimated using the restricted maximum likelihood method in REMLF90. Fixed effects on milk yield were also studied. In ewes with a 100% heterosis effect (ewes from purebred parents of different breeds), the heterosis effect increased milk production by 11.642 kg, milk fat production by 0.772 kg, and protein production by 0.565 kg per milking period. The effect of the Tsigai breed on milk production was -21.98 kg compared to Lacaune, while for the Improved Wallachian breed, the value was -38.58 kg. The Tsigai direct breed effect reduced fat production by 1.56 kg and protein production by 1.34 kg. The Improved Wallachian direct breed effect was -2.71 kg for fat production and -2.27 kg for protein production. Keywords: Tsigai, Improved Wallachian, Lacaune, heterosis effect, effect of breed, crossing Journal: Czech Journal of Animal Science Pages: 407-413 Volume: 68 Issue: 10 Year: 2023 DOI: 10.17221/39/2023-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/39/2023-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-202310-0001.txt Handle: RePEc:caa:jnlcjs:v:68:y:2023:i:10:id:39-2023-CJAS Template-Type: ReDIF-Article 1.0 Author-Name: Piotr Sablik Author-Workplace-Name: Department of Ruminant Science, West Pomeranian University of Technology, Szczecin, Poland Author-Name: Andrzej Dybus Author-Workplace-Name: Department of Genetics, West Pomeranian University of Technology, Szczecin, Poland Author-Name: Ewa Januś Author-Workplace-Name: Department of Cattle Breeding and Genetic Resources Conservation, University of Life Sciences in Lublin, Lublin, Poland Author-Name: Błażej Nowak Author-Workplace-Name: Department of Genetics, Wrocław University of Environmental and Life Sciences, Wrocław, Poland Author-Name: Wojciech Kruszyński Author-Workplace-Name: Department of Genetics, Wrocław University of Environmental and Life Sciences, Wrocław, Poland Author-Name: Anna Mucha Author-Workplace-Name: Department of Genetics, Wrocław University of Environmental and Life Sciences, Wrocław, Poland Title: Polymorphism of the PGLYRP1 gene, the value of selected performance and functional traits, and causes of culling in Holstein-Friesian red-white cows Abstract: This research paper addresses the hypothesis that the peptidoglycan recognition protein 1 (PGLYRP1) gene polymorphism (Tyr76His; dbSNP ID: ss104796364) has an influence on some performance traits and causes of culling in Polish Holstein-Friesian red-white cows. The study involved 134 cows kept on a farm in the south-west of Poland. PGLYRP1 genotypes TT, CT, and CC were detected. It was shown that compared with cows with genotypes CT and TT, the individuals with genotype CC were characterised by higher lifetime yields and higher amounts of lactation milk, fat, and protein. A beneficial effect of genotype CC, compared with genotype TT, was also noted in the case of the lifespan and, consequently, the length of the productive life and the average number of lactations. Diseases of the musculoskeletal system (genotypes CC and TT) and disorders of the reproductive system (genotype CT) were the most common causes of culling. An essential practical observation was the potentially higher susceptibility of cows with genotype CC to mastitis, which resulted in the necessity to cull over one-fifth of the animals in this group. Simultaneously, no cows in this group were culled due to low performance or metabolic, gastrointestinal, and respiratory diseases. Therefore, the PGLYRP1 gene seems to be a promising potential herd health marker; however, to consider it the main gene, it is necessary to extend the investigations to include more individuals and other breeds of dairy cattle. Keywords: dairy cattle, lactation, lifetime performance, length of production life Journal: Czech Journal of Animal Science Pages: 399-406 Volume: 68 Issue: 10 Year: 2023 DOI: 10.17221/194/2022-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/194/2022-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-202310-0002.txt Handle: RePEc:caa:jnlcjs:v:68:y:2023:i:10:id:194-2022-CJAS Template-Type: ReDIF-Article 1.0 Author-Name: Tomáš Janoš Author-Workplace-Name: Department of Livestock Science, Mendel University in Brno (FA), Brno, Czech Republic Author-Name: Jan Kuchtík Author-Workplace-Name: Department of Livestock Science, Mendel University in Brno (FA), Brno, Czech Republic Author-Name: Eliška Dračková Author-Workplace-Name: Department of Livestock Science, Mendel University in Brno (FA), Brno, Czech Republic Author-Name: Martin Hošek Author-Workplace-Name: Department of Livestock Science, Mendel University in Brno (FA), Brno, Czech Republic Author-Name: Tomáš Kopec Author-Workplace-Name: Department of Livestock Science, Mendel University in Brno (FA), Brno, Czech Republic Author-Name: Radek Filipčík Author-Workplace-Name: Department of Livestock Science, Mendel University in Brno (FA), Brno, Czech Republic Title: Growth, carcass and meat quality in Zwartbles lambs slaughtered at different live weights Abstract: The aim of the study was to evaluate the effect of different live weights at slaughter (LWS) of Zwartbles lambs on their daily gain (DG), carcass traits (CT) and chemical and physical characteristics of the quadriceps femoris muscle (QFM). A total of four weight groups of lambs were evaluated: group A, LWS = up to 35 kg; group B, LWS from 35.1 to 40 kg; group C, LWS from 40.1 to 45 kg and group D, LWS from 45.1 to 50 kg. The LWS had a significant (P < 0.05) effect on DG and most CTs, when average DG and most weights of individual CTs increased with increasing LWS. The evaluation of the influence of LWS on the chemical and physical characteristics of QFM primarily shows that this factor had a significant (P < 0.05) effect only on the content of intramuscular fat (IMF) and redness index (RI), when in both cases the values of these traits increased (IMF: from 0.57 to 1.21%; RI: from 8.53 to 9.76) with increasing LWS. In conclusion, it can be stated that most of the monitored traits in all weight groups of Zwartbles lambs were comparable with their levels in specialized meat breeds of sheep. Keywords: Zwartbles, live weight at slaughter, carcass traits, chemical characteristics of meat, physical characteristics of meat, quadriceps femoris muscle Journal: Czech Journal of Animal Science Pages: 414-422 Volume: 68 Issue: 10 Year: 2023 DOI: 10.17221/99/2023-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/99/2023-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-202310-0003.txt Handle: RePEc:caa:jnlcjs:v:68:y:2023:i:10:id:99-2023-CJAS Template-Type: ReDIF-Article 1.0 Author-Name: Thi Thanh Nhan Giang Author-Workplace-Name: The Key Laboratory of Animal Cell Biotechnology, National Institute of Animal Science, Hanoi, Vietnam Author-Name: Nguyen Van Ba Author-Workplace-Name: The Key Laboratory of Animal Cell Biotechnology, National Institute of Animal Science, Hanoi, Vietnam Author-Name: Thi Quynh Chau Nguyen Author-Workplace-Name: The Key Laboratory of Animal Cell Biotechnology, National Institute of Animal Science, Hanoi, Vietnam Author-Name: Khanh Van Nguyen Author-Workplace-Name: The Key Laboratory of Animal Cell Biotechnology, National Institute of Animal Science, Hanoi, Vietnam Author-Name: Lan Doan Pham Author-Workplace-Name: The Key Laboratory of Animal Cell Biotechnology, National Institute of Animal Science, Hanoi, Vietnam Title: Genetic diversity and maternal origin of Vietnamese indigenous chicken breeds inferred from complete sequences of mitochondrial DNA D-loop region Abstract: Indigenous chickens play a significant role in food security, income growth and socio-cultural life of rural households in Vietnam. This study was conducted to assess the genetic diversity as well as the phylogenetic relationships of Vietnamese indigenous chickens (Gallus gallus) to support the conservation of their genetic resources for sustainable rural farming.  In this study, the genetic diversity and the phylogenetic relationships of 10 Vietnamese indigenous chicken breeds were analyzed using complete sequences of mitochondrial DNA (mtDNA) displacement-loop (D-loop) region. The average nucleotide and haplotype diversities of Vietnamese chickens were 0.006 3 ± 0.000 22 and 0.918 ± 0.010, respectively. A total of 39 polymorphic sites and 29 haplotypes were identified. The maximum likelihood tree classified these haplotypes into seven haplogroups (A, B, C, D, E, G and V), with haplogroups A and B being the two predominant maternal lineages of Vietnamese indigenous chickens, while haplogroups C, D, E, G and V were found in the remaining chickens. Several haplotypes from different haplogroups were shared among some chicken breeds. These results suggested that Vietnamese indigenous chicken breeds have multiple maternal origins, mainly from Chinese, Southeast Asian and Indian chickens, and that these breeds share common maternal lineages. The high level of genetic diversity in Vietnamese chickens demonstrates significance of conservation for future use. Keywords: haplogroups, mtDNA, non-coding region, phylogenetic relationship Journal: Czech Journal of Animal Science Pages: 423-432 Volume: 68 Issue: 10 Year: 2023 DOI: 10.17221/226/2022-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/226/2022-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-202310-0004.txt Handle: RePEc:caa:jnlcjs:v:68:y:2023:i:10:id:226-2022-CJAS