Effects of Dry Period Length on Milk Production and Health of Dairy Cattle

• Published in: Journal of dairy science 2008-07, Vol.91 (7), p.2595-2603
• Main Authors: Watters, R.D., Guenther, J.N., Brickner, A.E., Rastani, R.R., Crump, P.M., Clark, P.W., Grummer, R.R.
• Format: Article
• Language: English
• Subjects: Animal Feed; animal health; Animal Nutritional Physiological Phenomena; Animal productions; Animal Welfare; Animals; Biological and medical sciences; bovine mastitis; calving; Cattle - physiology; Cell Count - veterinary; Colostrum; cow colostrum; dairy cattle; Dairying - methods; diet; disease incidence; dry period; dry period length; energy balance; Energy Intake - physiology; Energy Metabolism - physiology; Fatty Acids, Nonesterified - analysis; Female; Food industries; free fatty acids; Fundamental and applied biological sciences. Psychology; Immunoglobulin G; Lactation - physiology; lactation number; metabolic diseases; Milk - chemistry; Milk - cytology; Milk - secretion; Milk - standards; Milk and cheese industries. Ice creams; milk composition; milk fat percentage; milk protein percentage; milk quality; milk yield; Postpartum Period; somatic cell count; Terrestrial animal productions; Time Factors; Vertebrates
• ISSN: 0022-0302; 1525-3198
• DOI: 10.3168/jds.2007-0615

Holstein cows (n=781) in a commercial dairy herd were used in a randomized design to evaluate 2 dry period (DP) management strategies on milk production, milk components, milk quality, colostrum quality, and incidence of metabolic disorders. Cows were randomly assigned to a traditional 55 d (T) or shortened 34 d (S) DP. Cows assigned to T were fed a low-energy diet until 34 d before expected calving at which time all cows were fed a moderate-energy transition diet until calving. Postpartum, cows assigned to T produced more milk and tended to produce more solids-corrected milk than cows on S. Treatment differences in milk and solids-corrected milk yield were accounted for by cows in their second lactation. Milk fat percentage did not differ between treatments, but milk protein percentage was greater for cows assigned to S. Colostrum quality measured as IgG concentration did not differ between management strategies. Somatic cell score and cases of mastitis were not affected by management strategy. There was a tendency for prepartum nonesterified fatty acid (NEFA) to be lower for cows assigned to T compared with S. However, postpartum, cows assigned to S had significantly lower NEFA concentrations than those assigned to T. The incidences of ketosis, retained placenta, displaced abomasum, and metritis did not differ between treatments. Postpartum energy balance, as indicated by plasma NEFA, may have been improved for cows assigned to S; there was no detectable effect on animal health.