[Show abstract][Hide abstract] ABSTRACT: The effects of farm, parity (PO) and month of parturition on milk production, percentage of fat and protein, somatic cell count (SCC), and milk urea nitrogen (MUN) concentration were assessed on four specialized dairy farms using 120 cows. Also, the effects of MUN on gestation rate (GR) and artificial insemination rate (AIR) in early lactation were studied. The parameters of production and milk quality were similar among farms and were not influenced by the month of parturition. Farm D presented the highest MUN concentration. Concentration of MUN, percentages of fat and protein and SCC were not influenced by PO. Cows with a value of MUN between 10.1 and 13.0 mg/dL had the highest AIR and GR between days 55 and 70 postpartum and after 70 days in milk. These data suggested that MUN concentration was a useful parameter to predict the nutritional and reproductive stages of dairy cows.
Brazilian Archives of Biology and Technology 01/2009; 52. · 0.47 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Eight multiparous Holstein cows averaging 570 +/- 43 kg of body weight and 60 +/- 20 d in milk were used in a double Latin square design with four 21-d experimental periods to determine the effects of feeding ground or whole flaxseed with or without monensin supplementation (0.02% on a dry matter basis) on milk production and composition, feed intake, digestion, blood composition, and fatty acid profile of milk. Intake of dry matter was similar among treatments. Cows fed whole flaxseed had higher digestibility of acid detergent fiber but lower digestibilities of crude protein and ether extract than those fed ground flaxseed; monensin had no effect on digestibility. Milk production tended to be greater for cows fed ground flaxseed (22.8 kg/d) compared with those fed whole flaxseed (21.4 kg/d). Processing of flax-seed had no effect on 4% fat-corrected milk yield and milk protein and lactose concentrations. Monensin supplementation had no effect on milk production but decreased 4% fat-corrected milk yield as a result of a decrease in milk fat concentration. Feeding ground compared with whole flaxseed decreased concentrations of 16:0, 17:0, and cis6-20:4 and increased those of cis6-18:2, cis9, trans11-18:2, and cis3-18:3 in milk fat. As a result, there was a decrease in concentrations of medium-chain and saturated fatty acids and a trend for higher concentrations of long-chain fatty acids in milk fat when feeding ground compared with whole flaxseed. Monensin supplementation increased concentrations of cis9 and trans11-18:2 and decreased concentrations of saturated fatty acids in milk fat. There was an interaction between flaxseed processing and monensin supplementation, with higher milk fat concentration of trans11-18:1 for cows fed ground flaxseed with monensin than for those fed the other diets. Flaxseed processing and monensin supplementation successfully modified the fatty acid composition of milk fat that might favor nutritional value for consumers.
Journal of Dairy Science 07/2007; 90(6):2928-36. · 2.57 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: 2005. Milk production and milk composition of dairy cows fed Lac100 ® or whole flaxseed. Can. J. Anim. Sci. 85: 413–416. Cows were fed whole flaxseed or calcium salts of soybean oil as a fat source. Cows fed flaxseed had lower (P < 0.01) milk yield and higher (P < 0.01) percentages of fat and protein than cows fed calcium salts. Feeding whole flaxseed and calcium salts of soy-bean oil increased, respectively, the concentrations of alpha-linolenic acid and conjugated linoleic acid in milk.
The Canadian veterinary journal. La revue veterinaire canadienne 09/2005; 85(3). · 0.77 Impact Factor