Seroprevalence of human infection with Toxoplasma gondii and the associated risk factors, in Maiduguri, Borno state, Nigeria.

The prevalence of antibodies (IgG) to Toxoplasma gondii among 180 adults from the Nigerian city of Maiduguri was determined as 23.9%, using a commercial ELISA. Although the men investigated were more likely to be seropositive than the women, the difference was not statistically significant (27.3% v. 19.8%; P>0.05). There was also no apparent association between educational level and seroprevalence. There was a positive correlation between the mean antibody titre and the age of the subjects, with seroprevalence highest among the subjects aged 51-60 years and lowest in the subjects aged<21 years. Worryingly, 10 (20%) of the 50 female subjects who were of child-bearing age (15-40 years) were among those found seropositive for anti-T. gondii IgG. The mean antibody titres of the seropositive subjects ranged between 16.5 IU/ml (the threshold for positivity being 16 IU/ml) and >1000 IU/ml. In addition to age, occupation and eating habits were also significantly associated with seropositivity. Compared with the subjects who had no pets, dog owners were twice as likely to be seropositive. The relative risks for cat and dog ownership were, however, only 0.79 and 0.69, respectively, indicating that these animals might not be the main sources of human infection with T. gondii in the study area.

Detection of human rotavirus in faeces from diarrhoeic calves in north-east Nigeria.

Information on the epidemiology of rotavirus in any particular area is necessary for vaccine development against the disease caused by the virus. This study presents preliminary information on the prevalence of human rotavirus in diarrhoeic calves in North-east Nigeria. Faecal samples from 188 diarrhoeic calves in various farms in North-east Nigeria, obtained between November 1998 and February 1999, were analysed by ELISA for the presence of rotaviruses. A prevalence rate of 3.2% was recorded, with the virus being prevalent among calves aged 29-56 days (p < 0.05). The implications of these findings are discussed with respect to the close association between the herdsmen and their animals and the sharing of a common source of drinking water in the predominantly livestock-producing communities of North-east Nigeria.

The effects of subnutrition on the components of the gravid uterus in the doe.

The effects of subnutrition on the caprine fetus and the other products of pregnancy were investigated in does. Two groups of does were fed on rations calculated to provide 100 and 25% of their energy and protein requirements for maintenance from 19 days before mating until 60 days after mating. Estrus was synchronized in does using PGF(2x). Approximately 60 days after natural mating, pregnant does were slaughtered, and the products of pregnancy were measured. Fetuses from the feed-restricted group were significantly lighter (P<0.05), had shorter crown-rump length (P<0.05), and the uterus contained a smaller volume of fetal fluids (P<0.02). Curved crown-rump length tended to be shorter and fetal placental membranes and cotyledons tended to be lighter (P<0.1) in the feed-restricted group. No significant difference was found between the 2 groups in the head length, number of placentomes, and weight of empty uterus. The number of fetuses affected the number of placentomes (P<0.001), weight of empty uterus (P<0.001), mass of total fetal fluids (P<0.001) and weight of ovaries (P<0.05), but not fetal measurements. Gestation length was found to significantly (P<0.001) affect all the fetal measurements but none of the placental measurements except for the total weight of cotyledons (p<0.001). The results of the study demonstrated detrimental effects of underfeeding on the caprine fetus and placenta.

The effects of low level of feeding on response to synchronization of estrus, ovulation rate and embryo loss in goats.

Mature nonlactating British Saanen and Toggenburg does with a body score 2 were fed 25% (n=24) and 100% (n=16) maintenance rations from about 19 days before mating until slaughter at approximately 60 days after mating. Estrus was synchronized using PGF2alpha, and the ovulation rate was determined by laparoscopic examination of the ovaries once between Days 6 and 10 after mating. Pregnancy rate, potential kidding rate and embryo loss were determined by counts of viable fetuses at slaughter. The proportion of does in estrus within 96 hours of PGF2alpha administration was not different (P<0.5) between the feed-restricted and the maintenance groups (71.0% and 87.5%, respectively); however, the time of onset of estrus after PGF2alpha tended to be longer (P=0.12) in the feed-restricted group. Ovulation rate, incidence of multiple ovulations and proportion of does pregnant at 60 days were significantly lower (P=0.0004, P=0.025, P=0.05, respectively) in the restricted group. More embryos from single than multiple ovulations were lost in the restricted group (P=0.01). There was no difference in the overall ovulatory activity between right and left ovaries in the 2 groups. Transuterine migrations were observed in all does that had unilateral multiple ovulations. No migration was observed in does which had single ovulations. These data indicate that restricted feed intake in goats tended to delay the onset of estrus and lowered the ovulation rate, incidence of multiple ovulations, and pregnancy rate.