Effect of experimental trypanosomosis on body weight, packed cells volume and reproductive characteristics in <i>Gudali zebu</i> and <i>Namchi</i> taurine bulls

Abstract

Thirty-two young Gudali zebus and Namchi taurine bulls were infected to assess the effect of trypanosomosis on body weight (BW), packed cells volume (PCV) and some reproductive characteristics such as scrotal circumference (SC) and Testosterone (T), Luteinizing Hormone (LH) and Follicle Stimulating Hormone (FSH) blood levels. Gudali zebus are known to be trypanosusceptible, while Namchi taurine are trypanotolerant.  Trypanosomes were detected in the blood stream 14 days post infection. Parasitaemia reached the maximum on day 28 post infection. Trypanosoma infection led to significant decrease in weight gain (WG),  PCV and SC. These parameters were significantly lower in infected Gudali, compared to Namchi. There was a negative correlation (r = -0.66) between parasitaemia and PCV levels. Clinical signs such as fever, weakness, rough coat and weight loss were exhibited by day 28 post infection in Gudali bulls. There were significant differences between infected Gudali and Namchi for FSH and T levels. Significant negative correlations were registered between T levels and BW (r = -0.41) and scrotal circumference (r = -0.49).

Keywords: Reproduction, body condition, trypanosomosis, cattle.