Caracterización predial, rutinas de ordeño, niveles de mastitis bovina y calidad de leche en primavera, en dos predios de la provincia de Cautín, IX Región

Summary: With the objective to determine the effect of the addition of grain of canola to the concentrate of dairy cows, a study of 30 days of duration divided into pre-experimental period (15 days) and experimental period (15 days) was carried out, for which 10 were
selected, clinically healthy cows in similar numbers of birth and that were found between on the 60 and 120 of lactation. The cows selected were divided into two groups (5 cows by group). The group that consumed the concentrate with addition of canola treatment group
was called and the other corresponded to the control group. The effect of the addition of the grain of canola incorporated to the concentrate on the content of conjugated linoleic acid (CLA) in the milk fat, the quality of the milk and milk yield was evaluated. The isomers of CLA analyzed in the milk were the mixture cis-9, trans-11; trans-9, cis-11 and the isomer trans-10, cis-12, for the treatment group as for the control group.
Milk sample collected for analysis of CLA and quality of milk was carried out the days 15, 20, 25 and 30 of the experimental period for the belonging cows to the treatment group and control group. In order to determine the real contribute of the food consumed by the cows of the experiment an analysis proximal and of energy was carried out. Subsequently, a statistical analysis was carried out by means of test it t to evaluate the
existence of significant differences between the treatment and control group for the levels of CLA founded in milk fat. Moreover, by means of lineal regression were evaluated the content of milk fat and levels of CLA. The results revealed that does not exist you differences significant (P>0,05) for the values of the isomer mixes cis-9, trans-11; trans-9, cis-11 and the isomer trans-10, cis-12 between the control group and treatment group during the days 15, 20, 25 and 30 of the experiment. The analysis of the averages of the mixture cis-9, trans-11; trans-9, cis-11 and the isomer trans-10, cis-12 correspondent to the day 15, 20, 25 and 30 revealed an effect of the meadow in the increase of CLA in the day 20 for both groups. The
analysis of regression lineal revealed that did not exist relation between fat matter percentage and the levels of CLA founded in milk fat.