Revista Brasileira de Zootecnia
On-line version ISSN 1806-9290
COSTA, Patrícia Barcellos et al. Fat supplementation from different sources in the diet of Jersey cows in the initial lactation stage. R. Bras. Zootec. [online]. 2007, vol.36, n.4, pp. 888-895. ISSN 1806-9290. http://dx.doi.org/10.1590/S1516-35982007000400019.
The objective of this research was to evaluate the effects of fat supplementations as calcium salts of palm oil (PF), whole rice bran + rice oil (WRBO) and whole rice bran + bovine tallow (WRBT) on dry matter intake, productive efficiency and energy balance of dairy cows in the beginning of the first third period of lactation. Control diet contained 2.9% EE, while the diets GP, FAIO and FAIS contained 5.13; 5.29 and 5.16% EE, respectively. Pure bred Jersey cows of 2nd and 3rd lactation were used, with 70 days in milk, average weight of 420 kg and body condition of 3.5 to 4. A replicated 4 x 4 Latin square experimental design was used, with eight cows, four diets and four experimental periods. Each experimental period consisted of 21 days (14 days for adaptation and 7 for sample collection for the chemical analysis of milk and feeds. Milk production of 3.5% fat corrected milk (FCM 3.5%) was higher with the fat supplementation to the diet. There was no difference in dry matter intake. Fat supplementation showed better results for productive efficiency expressed as FCM3.5% in function of metabolic weight. Independently of lipid source, there was not effect of the diets on PLC3.5%, dry matter intake and productive efficiency, expressed as PLC3.5% in function of the metabolic weight. The addition of different fat sources to high production dairy cows diets could be viable, because its addition to the diet improved milk yield without alter feed intake.
Keywords : calcium salt of palm oil; energy balance; dry matter intake; milk production; productive efficiency; whole rice bran.