Macro-anatomical and morphometric studies of the hindlimb of grasscutter (Thryonomys swinderianus, Temminck-1827).

The hindlimb of the grasscutter (Thryonomys swinderianus, Temminck-1827) was studied using 12 adult (≥6 months) rats of either sex with the mean weights of 1.42 ± 0.20 kg and 0.82 ± 0.13 kg for buck (n = 6) and doe (n = 6), respectively (p < .05). Characteristics of the bones were studied by gross observation after their preparation. Measurements of different segments of the hindlimb were also taken, giving a total average length of 31.80 cm. Correlation coefficients between length of bone and weight of rats were positive (p < .05) in bucks for all bone segments, except the pes (p > .05), whereas those in does were all non-significant (p > .05), with significant sexual dimorphism in the relationships. The average total number of bones in the hindlimb was 92, with no apparent sexual dimorphism. The bones of the hindlimb revealed important differences and similarities in morphology with those of other rodents. The Os coxae presented a relatively large obturator foramen, formed by the ramus of the ischium and shaft of the pubis. The femur had a body and two extremities with a prominent head, well-defined neck and trochanter. The fibula, a slender bone with triangular-shaped proximal extremity, ran down the length of tibia with proximal attachment (via cartilage) and distal fusion, leaving an extensive interosseus space. The pes revealed eight tarsals and four metatarsals; each of the metatarsals showed three phalanges.

Seasonal, sex and live weight variations in feed and water consumptions of adult captive African Giant rats (Cricetomys gambianus, Waterhouse-1840) kept individually in cages.

Adult African Giant rats (Cricetomys gambianus, Waterhouse) (AGRs) (n = 231) of both sexes (117 bucks, 114 does) were live-trapped in the wild in Zaria, Nigeria. Live weight (LW), daily feed consumption (FC) and water consumption (WC) of the AGRs were measured during the cold-dry (CDS), hot-dry (HDS) and rainy (RS) seasons for 2 years with the aim of determining seasonal, sex and LW variations. Feed consumption was significantly different (p < 0.001) between all the seasons, with the lowest mean value recorded during the HDS, while the highest was obtained during the RS. Water consumption was also lowest (p < 0.001) during the HDS but did not differ significantly (p > 0.05) between the CDS and RS. Both feed and water consumptions were higher (p < 0.01) in the males (bucks) than the females (does) during the CDS and HDS, but the sex difference was not significant (p > 0.05) during the RS. Feed consumption correlated positively (p < 0.0001) with WC and relative humidity, but negatively (p < 0.0001) with LW, ambient temperature and heat index. In conclusion, both feed and water consumptions in AGRs decrease with increased seasonal heat and adult LW and are lower in does than in bucks during the dry seasons (CDS and HDS). Intervention may be indicated during the HDS to improve feed and water consumptions for optimal performance of the AGRs.

Antidiarrhoeal activity of the methanol stem-bark extract of Annona senegalensis Pers. (Annonaceae).

AIM OF THE STUDY: To investigate the antidiarrhoeal properties of the stem-bark extract of Annona senegalensis, using both in vivo and in vitro models. MATERIALS AND METHODS: Swiss albino mice were used to investigate the acute oral toxicity of the extract. The extract was administered orally to mice fed with charcoal meal in order to investigate intestinal transit time. The effect of the extract on contraction of isolated rabbit jejunum and the responses of the tissue to acetylcholine and histamine were also investigated. RESULTS: The extract was safe at doses up to 5000 mg/kg. The extract at the dose of 10mg/kg significantly (p<0.05) decreased intestinal transit time at concentrations of 0.2-3.2 mg/ml, the extract attenuated spontaneous contractions of the isolated rabbit jejunum, and those induced by acetylcholine in a concentration-dependent fashion. CONCLUSION: The extract decreased intestinal transit time by attenuating the spontaneous contractions of the intestine, thus the study provided a scientific basis for the use of Annona senegalensis stem bark extract in the treatment of diarrhoea.