The effect of maternal factors on growth, skeletal growth factors, and serum total protein of Holstein dairy calves

The aim of this study was to investigate maternal factors including dry period length, parity, calving type, calf number per calving, and calving body condition score on body weight (BW), serum total protein (STP) concentration, and body structure growth of female Holstein dairy calves.

152 Holstein dairy cows and their female calves were studied in this experiment. The calves were weighed at birth and moved to individual pens bedded with sawdust, Fresh colostrum samples were collected from 152 Holstein dairy cows. Maternal effects include: number of births from 2 to 5. Type of childbirth: single or multiple, natural or hard birth. Dry period length which includes: Group 1 - under 45 days. Group 2- 46 to 60 days. Group 3 - 61 to 75 days and group 4- Over 75 days. Calves' BW was also measured on days 30 and 60 of the study.

Birth BW was not affected by the mother's parity. The parity had an effect on the BW of calves at day 30 and 60, whereas, the lowest calves BW at day 30 was revealed in the five lactation cows. Also, the calves that were born to mothers who entered their second lactation were heavier than other calves at day 60 (P <0.05). Calf BW at birth, 30, and 60 days of age was affected by the number of calves at birth and the type of calving (P <0.05) so that singleton calves and normal birth calves had more BW. day 60 (P <0.05) was significant so that the mothers with dry period length less than 45 and more than 75 days had the lowest and highest 60-day calves BW. Serum total protein was affected by parity, calves’ number per calving, type of calving, and calving body condition score (P <0.05). In addition, the effect of calving type on STP concentration at birth and day 10 tended to be significant, while at day 35 normal birth calves had greater STP than dystocia birth calves. Withers height and body length in calves born to five lactations mothers were lower than other parities (P <0.05). Heart girth at birth and hip height at day 60 of age was higher in calves were born to mother with a dry period length more than 75 days (P <0.05). Body structure at birth and day 60 was higher for singleton calves than for twin calves and calves born with normal calving than calves born with dystocia (P <0.05).

The results of the current experiment showed that factors related to the physiological status of dams and calving type affect the immunity status and performance of infant's calves.