Abstract:
Proc. Aust. Soc. Anim. Prod. 1996 Vol. 21 EFFECT OF FAT PRILLS, PRE- AND POSTPARTUM ON LIVER TRIGLYCERIDE CONTENT, MILK YIELD AND COMPOSITION OF DAIRY COWS W.F. KOTZ�, P.I. WILKE and J.E.J. DU TOIT Dept of Animal Science, University of the Orange Free State, Bloemfontein, 9300, South Africa Increasing dietary energy density by feeding supplemented fat may enhance lactation performance as well as metabolic efficiency of lactating cows (Kronfeld 1980). Inadequate energy intake prepartum and during early lactation has been associated with increased incidences of metabolic disorders (Curtis et al. 1985) and poor reproductive performance. The aim of this study was to determine the effects of pre- and postpartum supplementation of dietary fat on milk production and liver triglyceride concentration in dairy cows. Twelve high yielding multiparous Friesian cows were blocked at random in 2 groups 5 weeks prior to par-turn in a Latin Square change-over design. The cows were housed individually in pens and the diets were offered ad libitum twice daily. Treatments were as follows: basal diet (mixed ration) and basal diet supplemented with 5OOg/day fat (Prilplus 10). Prilplus 10 is a protected fat and was fed with the morning feeding. Milk yield was recorded daily and milk composition determined fortnightly. Liver biopsies were taken by percutaneous needle biopsy 5 weeks before and 2 days and 5 weeks post parturition. All data were analysed statistically by analysis of variance. Results are presented in Table 1. Table 1. Milk production, milk composition 5 weeks post partum and triglyceride (TG) content of liver biopsies from dairy cattle. (Mean value f SD) CURTIS, C.R., ERB, H.N., SNIFFEN, C.J., SMITH, D.R. and KRONFELD, D.S. (1985). J. Dairy Sci. 68: 2347-9. KRONFELD, D.S., DONOGHUE, S., NAYLOR, J.M., JOHNSON, K. and BRADLEY, C.A. (1980). J. Dairy Sci. 63: 545-9. 340
