Comparative Assessment of Growth Structure and Litter Size of Grasscutter (Thryonomys Swinderianus Temminck, 1872) Bred In Captivity

Cane rats under domestication and multiplication in Forestry Research Institute of Nigeria, Ibadan were assessed for their population growth, structure and analysis over a period of five years (2009-2013). On the basis of weight gain, fecundity and docility, thirty-two (32) female grass cutter were selected for reproduction. A buck (male) was provided with one to three does (females) for mating and the mating group continued to live together until pregnancy was observed. These animals were housed in floor hutches constructed with 6-inch hollow blocks. The off springs were monitored for sex ratios and population growth and data generated were subjected to analysis using both continuous statistics of percentages and inferential statistics of X2.  Continuous statistics results revealed that more cases of parturition occurred during rainy season than dry season probably due to high quality forage that is always available during the season but inferential statistics did not establish it  Analysis also showed that more female grass cutter were produced than males on yearly basis but mortality affected more females than males probably because the stress of continuous parturition coupled with age may weaken their   resistance against diseases and environmental fluctuations. Also, mortality figure was higher during wet than dry season, implying that the animals need more care and medical care during rainy season. These observations are subjects of further research. Keywords. Cane rat, domestication, parturition, litter, sex ratio, mortality

Effect of variation in temperature and relative humidity on the reproductive performance of grasscutters held in captivity

This study investigated the reproductive performance of grasscutter through oestrus, mating, parturition, abortion and litter size in establishing the success of this performance during the rainy season and dry season. Effects of the atmospheric temperature and relative humidity on the reproductive performance of grasscutter in captivity were duly observed. Twenty female grasscutters were used with ten males for mating and were subsequently individually caged to determine the outcome of male-female contact (i.e. mating, conception and parturition). The signs of mating were detected by observing the marks of climbing at the back of the female grasscutter (doe),observing the changes in the perineum of the female before and after mating, monitoring the changes in weight gained post-mating and presence of fetuses by abdominal palpation. Parturition was detected by monitoring the expectant mothers with successful mating signs and distended abdomens. Keywords: Grasscutter, reproductive performance, reproduction, parturition, mating

Implic ations of climate change and deforestation on behavioural patterns among fauna species in national parks and protected areas.

Climate change and deforestation are significant in the shift of age-old weather and seasonal cycles in biological and agricultural activities. Indiscriminate forest exploitation leads to deforestation also, release of CO2 and other pollutants tampers with ozone layer which has been acting as a big umbrella against ultraviolet radiation. This paper discusses effects of climate change and deforestation on physical environment as they affect animal population, distribution and general physiology in response to shift in climatic parameters in their habitats. Steps to ameliorate impacts of climate change and deforestation such as environment-conscious methods of waste disposal, minimal air pollution and introduction of Environment Education with Biodiversity Conservation (as Secondary School subjects) are mentioned also.Key words: climate change, deforestation, national parks, global warming, ozone layer, biodiversit