Semen sialic acid surge and modulation of alpha-L-fucosidase activity: possible link to loss in reproductive capacity during trypanosomiasis.

The profiles of semen sialic acid and the enzyme alpha-L-fucosidase were studied in rams undergoing chronic infection by Trypanosoma congolense. Our data showed a significant surge in the level of sialic acid with parasitaemia. The pattern followed a polynomial function we had reported for erythrocyte sialic acid in mice undergoing acute infection by T.

Sequential testicular and epididymal damage in Zebu bulls experimentally infected with Trypanosoma vivax.

Six Zebu bulls aged between 31 and 34 months exhibiting good libido were used to study sequential testicular and epididymal damage in Trypanosoma vivax infection. Three bulls were infected with T. vivax, while the other three served as controls.

The effects of trypanosomosis on sperm morphology in Zebu x Friesian crossbred bulls.

Detailed studies of sperm morphological abnormalities were carried out on 12 Zebu x Friesian crossbred bulls used in a study of the effects of trypanosomosis. Four bulls were infected with T. vivax, another four with T.

Effects of Trypanosoma vivax and Trypanosoma congolense infections on the reaction time and semen characteristics of Zebu (Bunaji) x Friesian crossbred bulls.

The effect of trypanosomosis on reaction time and semen characteristics of 12 Zebu (Bunaji) x Friesian crossbred bulls aged between 3 and 5 years was studied for a duration of 12 weeks. Four of the bulls were infected with Trypanosoma vivax, another four with Trypanosoma congolense and the remaining four bulls served as controls. Rectal temperatures and haematological parameters were monitored twice weekly.

Effects of nutritional supplementation and exposure to bulls on resumption of post-partum ovarian activity in Bunaji (Bos indicus) cattle.

A total of 51 pluriparous post-partum Bunaji (Zebu) cows belonging to agropastoralists were involved in a 2 x 2 factorial experiment for a period of 180 days. The cows were assigned randomly at calving to four treatments: (1) grazing only (no supplementation) and exposure to bull (NSBE); (2) grazing only (no supplementation) and no exposure to bull (NSNE); (3) grazing plus feed supplementation (each cow received 600g of 20.8% crude protein of whole cottonseed supplement per day) and exposure to bull (FSBE); (4) grazing plus feed supplementation and no exposure to bull (FSNE).