The study presents a comprehensive investigation into the genetic determinants of 100-day milk yield (100DMY), 305-day milk yield (305DMY), total milk yield (TMY), and persistency using first lactation records of 374 Holstein heifers reared in a private farm at Çanakkale province of Türkiye, employing a genome-wide association study (GWAS) approach. The research underscores the substantial genetic component underlying these economically important traits through detailed descriptive statistics and heritability estimations. The estimated moderate to high heritabilities (0.32–0.54) for milk production traits suggest the feasibility of targeted genetic improvement strategies. By leveraging GWAS, the study identifies many significant and suggestively significant single nucleotide polymorphisms (SNP) associated with studied traits. Noteworthy genes have identified in this analysis include BCAS3, MALRD1, CTNND2, DOCK1, TMEM132C, NRP1, CNTNAP2, GPRIN2, PLEKHA5, GLRA1, SCN7A, HHEX, KTM2C, RAB40C, RAB11FIP3, and FXYD6. These findings provide valuable understandings of the genetic background of milk production and persistency in Holstein cattle, shedding light on specific genomic regions and candidate genes playing pivotal roles in these traits. This research contributes valuable knowledge to the field of dairy cattle genetics and informs future breeding efforts to improve milk production sustainability and efficiency in Holstein cattle populations.

The aim of the study was to evaluate live weights, body measurements, and real-time ultrasound carcass traits of F1 and BC1 genotypes in a marker assisted introgression (MAI) process. Effects of some factors on live weight and body measurements including ultrasonographic assessments in Musculus longissimus dorsi (MLD) were investigated at the F1 (n=51) and BC1 (n=99) cross lambs born in 2015 – 2017 period. Variance analysis showed that genotype had significant (P < 0.001) effect on pre- and post-weaning growth characteristics. The birth type had significant (P < 0.05) effect on pre- and post-weaning growth traits. Live weights at twelve months of age were higher in heavier born lambs. The growth performance of F1 lambs was between Texel and Ramlıç. Myostatin heterozygous BC1 lambs had been potentially heavier than the non-carriers and pure Texel. MLD depth and area were also statistically higher (P < 0.05) in BC1 lambs carrying myostatin than non - carriers. As a result, the beginning phase of introgression processes implemented was found to be successful

As in the European Union, new sets of animal welfare standards have been implemented in Türkiye, a candidate country for EU membership. However, there is still a limited amount of data available to form the basis of policy measures aimed at improving the welfare of animals in the extensive and semi-extensive sheep production systems. Türkiye's geographical and climatic characteristics at the crossroads of continents influence semi-extensive sheep production. This study was conducted in 56 commercial sheep farms in the Emirdağ district of Afyonkarahisar Province, Türkiye, to assess sheep welfare and to identify key welfare risks using the animal-based assessment protocol of the Animal Welfare Indicators (AWIN) project. Each farm was visited once, and data on the physical conditions of housing and equipment were obtained by measuring or observing, while data on animal management were obtained by interviewing farmers. A total of 702 sheep were individually assessed on the farms as part of the animal-based sheep assessment using the AWIN protocol. Animal management practices, including providing adequate space per animal (1.7 m²), hand milking, veterinary consultation, avoiding painful mutilations in lambs, and bottle-feeding weak newborn lambs, supported sheep welfare. No cases of excessive scratching, myiasis, leg problems, or clinical mastitis were observed. Major body lesions were rare (major lesions were mostly found on the udder at 0.65 % and least on the legs at 0.00 %), while lameness (1.3 %) and hoof overgrowth (6.27 %) were at relatively low levels. No animals exhibited social withdrawal or stereotypical behavior. Poor body condition (30.04 %), severe faecal soiling (36.85 %), wet and soiled fleece (48.65 %), poor wool quality (22.94 %), and respiratory problems (9.30 %) may result from poor air quality, inadequate comfort, and insufficient floor hygiene in barns. Potential welfare risks were identified as follows: milking sheep immediately after birth; negative human–animal interactions; the lack of loading ramps, water, and shade in village pastures, as well as of regular foot care, mastitis and lameness control programs, and farm records. As a result, this study provides insight into the animal welfare of animals on family sheep farms in Inner West Anatolia, Türkiye, and highlights the need for high-quality feed, better housing conditions, and good animal handling. The findings could be used to support policies to improve animal welfare standards, including barn design, animal welfare management, and awareness of animal needs.

The aim of the study was to evaluate the growth, body and ultrasonic measurements and some carcass traits of purebred Ramlıç, Texel and crossbred (87.5 % Ramlıç and 12.5 % Texel) lambs in a marker-assisted introgression (MAI) project. The effects of some environmental factors such as genotype, sex, birth type, dam age, weaning age, and birth weight on growth, ultrasound measurements, and carcass traits were significant (P<0.05). There were no significant differences between pure Ramlıç and its myostatin carrier ($+/-$ ) and non-carrier ($-/-$ ) second backcrosses (BC₂) for birth weight, daily live weight gain, and weaning weight. The BC₂ genotype ($+/-$ ) was statistically caught up with pure Ramlıç for wither height, body length, and rump width. Differences in the longissimus muscle depth indicated that the BC₂ ($+/-$ ) genotypes tended to be better for both pure Ramlıç and Texel lambs. Texel lambs were superior to Ramlıç in the aspect of some carcass characteristics such as leg length, cold right-half carcass weight, foreleg weight in the left-half carcass, and muscle weight in the left leg. BC₂ ($+/-$ ) lambs were in the middle of both breeds for the traits. BC₂ lambs carrying myostatin did not vary from Ramlıç morphologically. The new type of Ramlıç was also closer to Texel in the aspect of carcass characteristics. In this connection, improvement of indigenous breeds could be achieved by MAI without changing the essential characteristics. For the summary, please visit http://www.mustafatekerli.com (last access: 14 June 2022).

The goal of this study was to estimate (co) variance components and genetic parameters for pre- and post-weaning growth traits in Dağlıç sheep, considering the direct additive genetic, maternal genetic, and maternal permanent environmental effects, with different statistical models. The information of 21,735 native Dağlıç lambs born between 2011 and 2021 was used to estimate (co) variance components by the Average Information-Restricted Maximum Likelihood algorithm. The results showed that the most suitable model was Model 3 for birth weight (BW), average daily gain (ADG), and weaning weight (WW). Model 4 was the most appropriate for weight at three (W3), weight at six (W6), and weight at twelve months of age (W12). The direct heritabilities for BW, W3, ADG, WW, W6, and W12 were 0.35 ± 0.02, 0.36 ± 0.03, 0.27 ± 0.02, 0.22 ± 0.02, 0.47 ± 0.05, and 0.47 ± 0.05, respectively. Genetic and phenotypic correlations amongst the traits were in the range of 0.103 ± 0.008 to 0.995 ± 0.002. These results can be used for the improvement of growth traits in the Dağlıç breed of sheep through selection.