ABSTRACT The objective with this research was to compare milk quality parameters among herds characterized by different levels of milk production. The research involved 1080 bulk milk samples collected from 30 dairy herds, which produce milk for Parmigiano Reggiano cheese, during three years. Each milk sample was analysed for fat, crude protein, titratable acidity, total bacterial count, somatic cells, coliform bacteria, and Clostridia spores. Least mean values were obtained by ANOVA using milk production intervals from 6000 to 7999 (L-group), […]

This study investigated the effect of a supplement containing whole rice bran and crude glycerin for 21 days before mating on metabolic, productive, and reproductive responses of 28 primiparous suckling beef cows. Cows were randomly assigned to a control group (CON, n = 14), grazing on grasslands, and a supplemented group (SUP, n = 14), grazing on grasslands and supplemented daily individually with 1 kg dry matter (DM) of whole rice bran + 550 mL crude glycerin (224 g kg−1 […]

The objective of this study was to evaluate production and composition of milk from cows fed silages containing potato. Twelve females were selected: nine between 50 and 70 months of age and three between 36 and 42 months of age, lactating, with approximate weight of 550 kg. The experimental design consisted of 12 cows in three 4 × 4 Latin Squares, with four experimental periods and four treatments: silages of corn (CS); elephant grass (ES); elephant grass activated with 7% […]

The objective of this study was to evaluate the association of non-dietary factors on the concentration of milk urea nitrogen (MUN), as an indicator of efficiency of nutrient utilization by lactating dairy cows. A dataset containing 7,006 observations from 855 lactating Holstein cows were used. Milk yield, body weight, days in milk and number of lactation were collected on the milk sampling days. Monthly samples of milk were collected to determine contents of milk fat, protein, lactose, total solids, MUN […]

The objective of this study was to evaluate milk yield and some physico-chemical characteristics of milk from Mediterranean buffalo cows raised in western São Paulo. A total of 1438 observations was collected from 152 lactations that occurred from 1985 to 1995, at the Experimental Station of Andradina. The data were analyzed by means of the GLM procedure of SAS. The statistical model for milk production had month and lactation as fixed effects. The model for chemical constituents included milk yield […]

ABSTRACT – The objective of this paper was to determine the economic weights for the use in selection index for protein, fat and milk without fat and protein (carrier) appropriated for the payment systems of two important milk processors in the States of Parana and Minas Gerais. The prices of each one of those components were calculated, and the prices for protein, fat and carrier were 1.35, 1.89 and 0.17 R$/kg, in Parana, and 0.20, 0.80 and 0.20 R$/kg, in […]

The objective of this work was to exam the convenience of paying for the genetic value of protein and fat in imported semen using the technique of discounted gene flow, based on economic values derived in a parallel paper and literature biological parameters. In the State Parana, semen of Holstein sires positive for protein and fat could be economic, depending on its cost, while in Minas Gerais such sires would be unprofitable. Genetic trends for protein and fat in Brazilian […]