Temperamento de vacas leiteiras Holandês-Gir e sua relação com o desempenho produtivo

Abstract

The objectives of this study were to evaluate the consistency of temperament traits of primiparous F1 Holstein-Gyr cows throughout time and across distinct handling situations (during milking and during handling in the corral), and to assess the relationships between temperament traits and milk yield. The milking temperament was characterized by the movement of the hind legs (number of steps and kicks), in addition to recording the frequencies of defecation, urination, rumination and kicking off the milking cluster, as well as recording individual daily milk yield. To evaluate temperament in the handling corral, the following data were recorded: ET (time to walk along the single-file race and enter the squeeze chute); CS (crush score, assessing the reactivity within the squeeze chute, in scores from 1 = no movement to 4 = frequent and vigorous movements); FS (flight speed); FD (flight distance) and NOT (novel object test, recording latency for the animal to interact with an unfamiliar object). The number of steps during milking was negatively correlated with ET (r = -0.285; P < 0.01) and positively with FS (r = 0.355; P < 0.01), FD (r = 0.245; P < 0.05) and NOT (r = 0.283; P < 0.05), indicating that the animals which took a greater number of steps during milking were faster to enter and exit the squeeze chute, kept a greater distance from the observer and were more cautious to interact with the novel object. In turn, the frequency of kicking off the milking cluster was positively correlated with ET (r = 0.230; P < 0.05) and CS (r = 0.322; P < 0.01), but negatively with NOT (r = -0.386; P < 0.01), indicating that the animals that kicked off the milking cluster down were more reactive in the chute and had a greater disposition to interact with the novel object. Milk yield was negatively correlated with the number of kicks (r = -0.244; P < 0.05) and positively to the rumination (r = 0.324; P < 0.01). Rumination was the only behavioral trait with effect on the milk yield (F2,78 = 4.02; P < 0.05). However, the reactivity of the Holstein-Gyr dairy cows in the management corral was not related to the production (P > 0.05). Animal temperament was consistent over time and through the different handling situations and milking temperament was associated with milk yield of the cows, unlike temperament in the corral.