Effect of Feeding Different Levels of Corn Silage on Milk Yield and Quality in Dairy Assaf Ewes

Abstract

This study aimed to investigate the impact of feeding by different corn silage (CS) proportions on ewes milk yield and fatty acids composition. Twenty-one lactating Assaf ewes were divided into 3 groups (7 ewes each). The following dietary treatments based on increasing the proportion of CS in the total mixed ratio (TMR) were tested; (1) 47 % AH (0 % CS in the TMR) correspond to 0 % CS, (2) 23.5 % AH (23.5 % CS in the TMR) correspond to 50 % CS, and (3) 0 % AH (47 % CS in the TMR) correspond to 100 % CS. After 8 weeks of feeding, the type of diet had no significant effect on milk yield and solid; however, it significantly affects the milk fat. The levels of C8:0 and C14:0 were not affected by different silage levels. While the C10:0 and C12:0 significantly increased when fed on a 100 % CS diet. However, a significantly lower level of C16:0 (33.22 %) was observed in the 100 % CS compared to feeding on silage at 50 and 0 % (40.66 and 37.98 %, respectively). Similar trend was observed for C18:0, the lowest was in 100 % CS compared with the different feeding diets (7.52, 12.69, 10.61 % for 100, 50, 0 %, respectively). Total USFA in milk were decreased (p < 0.05) by feeding 100 and 50 % CS compared to 0 % CS feeding. It can be concluded that the replacement of alfalfa with CS had some influence on milk composition, especially the fatty acids profile.
 HIGHLIGHTS
 
 Utilization of nonconventional feed ingredients is important to reduced feed cost and improving its nutritive value
 Milk composition, especially the fatty acids profile when replaced portions of alfalfa can be affected by feeding corn silage
 More research is needed to confirm our findings