ABSTRACT:
The objective was to evaluate the effects of different levels of banana peel inclusion on the physiological variables of lactating F1 Holstein × Zebu cows. Ten cows distributed in two 5 × 5 Latin squares were used. Five experimental diets were tested: sorghum silage (control group); and the addition of 15%, 30%, 45%, and 60% of banana peel to replace sorghum silage. The experiment lasted 80 days. The environmental and physiological variables of the animals were measured. The Black Globe-Humidity Index presented an alert situation in the morning shift and a dangerous situation in the afternoon shift. The respiratory rate was not influenced by the levels of banana peel inclusion (P > 0.05) in the morning shift. However, it was influenced (P < 0.05) in the afternoon shift. The levels of banana peel inclusion in the diet did not affect the rectal temperature. Under the study environmental conditions, the level of up to 60% of banana peel replacing sorghum silage did not alter the physiological variables of thermoregulation in F1 Holstein × Zebu cows.
Key words:
respiratory rate; semiarid; by-product; rectal temperature