Association of age and body weight of animals in different physiological period with rates of culling due to disease

The aim of the study was to analyze the indicators of animal attrition from the herd, namely their age and body weight dynamics, in various physiological periods, taking into account the groups of nosologies. The analysis was performed using data obtained from the Information Analytical System "SELEKS. Dairy Cattle" and related to the attrition of 37,344 cows from dairy herds of 26 agricultural enterprises of the Republic of Tatarstan. The emphasis was placed on the fact that the reason for culling was one or another veterinary pathology. All nosologies were structured into the following groups: diseases of the reproductive system and various obstetric and gynecological diseases (OGD), internal diseases of non-communicable etiology (INCD), surgical pathology and diseases (SD), contagious diseases of infectious and invasive nature (IID). Cows culled from herds as a result of AGD are characterized by maximum body weight values of 6 (168.70 kg), 10 (260.90 kg) and 12 (306.87 kg) months, the last completed and maximum lactation – 555.92 and 541.44 kg, respectively, as well as minimum age values of the first, first effective insemination and first calving - 18.66, 18.91 and 27.47 months, respectively. Animals culled due to INCD differ in the maximum body weight at birth (32.46 kg), at 18 months (417.37 kg) and during lactation (577.43 kg), as well as the minimum body weight at the first insemination – 395.46 kg. Individuals culled from the herd as a result of SD are characterized by the maximum age of the first calving (28.61 months), body weight at first and effective insemination – 400.99 and 404.83 kg, respectively, as well as the minimum values of body weight at birth (30.71 kg), body weight at 10, 12 and 18 months – 253.74 kg, 299.43 and 406.10 kg, respectively. Cows culled as a result of IID are characterized by the maximum age of the first and first effective insemination – 22.49 and 22.42 months, respectively, as well as the minimum values of body weight at 6 months – 161.75 kg, at the first effective insemination – 397.63 kg, lactation – 541.68 kg, including the last completed and maximum – 520.72 kg and 514.00 kg.