Improved Calf Health Benefits Long-Term Performance
Results of recent studies show calf health has lasting effects.
In recent years, research has shown the importance of calf growth and development early in life. These studies show calf health is an investment that pays off over the long term in reduced mortality and improved productivity during lactation.
Distributor sales representatives can use this information to help show the return-on-investment for healthcare, housing, and nutrition.
Effect of pre- and post-weaning nutrition on reproductive tract development 1
University of Alberta researchers investigated the carry-over effects of pre- and postweaning planes of nutrition on prepubertal reproductive tract development and postpubertal estrous cycle characteristics in 36 Holstein heifers. The calves were divided into two groups with the same colostrum management. Then provided a “low” or “high” pre-weaning or post-weaning diet.
The authors found a positive carryover effect by increasing the preweaning level of nutrition from 5 to 10 L of whole milk/day on prepubertal follicular growth. Also, using 85% of concentrated dry total mixed ration during postweaning advanced reproductive development through greater endometrial thickness and follicular growth in the prepubertal phase and increased the population of antral follicles in the postpubertal estrous cycle of Holstein heifers, compared with a 70% of a concentrated total mixed ration.
Read the complete article in the Journal of Dairy Science.
Milk-fed calves outpace replacer-fed calves during the first lactation 2
Researchers at the Volcani Center in Israel evaluated 40 Holstein calves from 5 days of age through their first lactation. The calves were allotted to two groups. One was fed milk replacer for the first 50 days of life, and the other group was milk-fed. After weaning, all calves were fed the same diet to 180 days of age. At 180 days, one subgroup was supplemented with 2% crude protein.
Yields of milk and fat-corrected milk (FCM) were greater for the milk-fed and crude protein supplemented heifers than for the heifers fed milk replacer. In this study, nursing affected body weight, decreased the age of puberty onset, and increased FCM yield at first lactation. Supplementing the diet with 2% crude protein during the prepubertal period increased body weight and 305-day milk and FCM yields during the first lactation.
Read the complete article in the Journal of Dairy Science.
Late-gestation heat stress results in calves with lower weight at weaning 3
Heat stress during late gestation affects cows during both the pre- and postpartum periods. In addition to impaired immune function during the transition period, heat stress during the dry period adversely affects mammary gland development before parturition and exerts residual effects on metabolism in early lactation and subsequent lactational performance.
Maternal heat stress in late gestation also compromises placental development and fetal growth and negatively affects the immune competence of the offspring. These observations suggest the importance of heat stress abatement as an easily implemented, noninvasive method for managers to improve dry cow performance and calf health and growth.
Read the complete article in the Journal of Dairy Science.
Other research notes:
- Management and nutritional practices during early life have three to seven times more influence on future milk production than sire selection.4
- For each pound of pre-weaning daily gain, milk production increased by 1,540 lbs. in the first lactation or 6,000 lbs. over three lactations.4
- Penn State University researchers concluded that pre-weaned calves with average daily gains greater than 1.1 lbs./day have greater first-lactation milk yields.4
- Scouring calves treated with antibiotics gave 1,086 lbs. less milk during their first lactation than those not treated, indicating prolonged damage to the intestinal tract or other complications may occur. 4
1 Bruinjé, T.C. et al. Carryover effects of pre- and postweaning planes of nutrition on reproductive tract development and estrous cycle characteristics in Holstein heifers. Journal of Dairy Science (102);11:10514 – 10529.
2 Shamay, A. et al. Effect of Nursing Management and Skeletal Size at Weaning on Puberty, Skeletal Growth Rate, and Milk Production During First Lactation of Dairy Heifers. Journal of Dairy Science (88);4:1460 – 1469.
3 Tao, S. et al. Invited review: Heat stress effects during late gestation on dry cows and their calves. Journal of Dairy Science (96);7:4079 – 4093.
4 Amaral-Phillips, D.M. Dairy Calf Management Practices Impact Future Production. University of Kentucky College of Agriculture, Food and Environment.
