Evaluation of calf mortality in cattle breedings within the scope of breeding practices

This study was conducted to determine certain breeder characteristics, the structural features of dairy cattle farms, calf mortality levels, and the effects of management practices related to the care and feeding of dams and calves on calf mortality in dairy farms in Ankara Province. For this purpose, the study was carried out in 361 farms determined by power analysis using stratified and random sampling methods across 9 central districts of Ankara (Altındağ, Çankaya, Etimesgut, Gölbaşı, Keçiören, Mamak, Pursaklar, Sincan, and Yenimahalle). Data were collected through face-to-face surveys conducted voluntarily with breeders and through on-site observations, inspections, and evaluations during farm visits. The survey used in the study comprised three sections: structural characteristics of the farms and breeder profiles, care and feeding practices for cows, and care and feeding practices for calves. The results indicated that approximately half (50.4%) of the breeders had secondary or high school education. The majority of barns (77.3%) were closed-type, with concrete flooring used in 65.9% of farms. Calf pens or hutches were present in 61.2% of the farms, most commonly made of concrete (34.4%). Only 27.1% of farms had a separate calving pen, while ventilation was mainly provided by natural ventilation and windows (94.5%). A record-keeping system was absent in 66.2% of farms. Only 26.3% of farms applied septiserum to pregnant cows, dystocia was observed in 18.6% of them, and abortions occurred in 16.34%. Among abortion causes, diseases were the leading factor (45.76%), and abortion cases were recurrent in 15.25% of the farms. Vaccinations affecting colostrum quality, such as rota and corona vaccines, were not administered in 62.0% and 62.9% of the farms, respectively. Disinfection practices were absent in 29.36% of the farms, and lime was the disinfectant used in 63.01% of those that did perform disinfection. In 70.4% of farms, calves were housed separately from their dams; only 18.3% housed calves individually in pens or hutches. Postnatal care practices included umbilical cord disinfection in 50.14% of farms and drying of the calf in 50.42%. Colostrum was fed in 98.6% of farms, immediately after birth in 48.32%, and 1–2 times daily in 84.5%. Septiserum was administered to calves in 84.6% of farms. Calf mortality due to dystocia occurred in 14.68% (53 farms), vitamins were given in 86.4%, antiparasitic drugs in 62.9%, and milk was fed at 10% of the calf's live weight in 50.7%. Individual bottles were used in 44.8%, weaning was done at 3 months of age in 56.0%, and bottle disinfection was not practiced in 90.99%. Calves were first introduced to feed at 3 weeks of age in 29.1% of farms. Bedding was changed twice daily in 5.8%, and once daily in 49.0% of the farms. Calf illness within the first six months occurred in 46.5% of farms, and veterinarians were consulted in 62.6% of these cases. The main challenges were treatment costs (42.9%) and medication prices (42.1%). In the past year, calf mortality was reported in 76.7% of the farms, with the highest mortality observed between the 2nd and 4th weeks postpartum in 45.1% of farms. Of the deceased calves, 72.56% had normal deliveries. Abortion was reported in 59 farms, and calf mortality during dystocia occurred in 53 farms. Mortality rates were 8.11% for calves born from normal deliveries, 1.98% from dystocia, and 0.42% from cesarean section. The overall postnatal calf mortality rate was 10.51%, while the total pre- and postnatal mortality rate was 14.39%. Respiratory system diseases accounted for 10.47% of calf deaths, and digestive system diseases for 72.56%. Most deceased calves were from dams aged 3–5 years. Calf deaths were most common in December, January, and February. Necropsy was performed in only 8.3% of the cases.