BREED VARIATION IN THERMOREGULATORY PARAMTERS AND THEIR CORRELATED RESPONSES IN SOME SELECTED INDIGENOUS CATTLE

Abstract

The study, breed variation in thermoregulatory parameters and their correlated responses in some selected indigenous cattle was conducted to evaluate breed differences in thermoregulatory parameters of four Nigerian indigenous breeds of cattle (Bunaji, Rahaji, Bokoloji and Adamawa Gudali). A total of eighty (80) cattle were used for the experiment (20 from each breed). Data were taken three times within the period of three months (August- October) and were subjected to ANOVA using SAS software. Parameters measured were rectal temperature, respiratory rate, pulse rate and Heat Tolerance Coefficient . There were significant (p<0.05) effect of breed all the parameters measured except (p>0.05) rectal temperature. Bokoloji recorded the highest in respiratory rate (21.80 beats/minutes) and Heat Tolerance Coefficient (1.91) while the highest recorded value for pulse rate (22.10) was in in Bunaji. The correlation coefficient between parameters shows that significant (p<0.05; r = 0.40- 0.49) positive relationship exist between HTC and RR in all the breeds studied. Also, significant (p<0.05; r = 0.29- 0.31) negative relationship exist between PR and RT except for the positive relationship (p< 0.05; r = 0.73) in Rahaji breed. It was concluded that Bokoloji and Bunaji breeds of indigenous cattle are more reactive to heat stress than Rahaji and Adamawa Gudali. Also, correlated responses within breed for thermoregulatory parameters can be maximized for selecting animals for improved heat tolerance.