Sexual dimorphism with respect to the macro-morphometric investigations of the forebrain and cerebellum of the grasscutter (Thryonomys swinderianus) / Dimorfismo sexual en relación con la investigación macro-morfométrica del cerebro y cerebelo del grasscutter (Thryonomys swinderianus)

This study was carried out to record the morphometric parameters of the brain of male and female grasscutters. Ten healthy grasscutters (5 males and 5 females) were used in this study. The mean brain weights were 9.80 + 0.50 g and 10.27 + 0.45 g for males and females respectively. The olfactory bulb mean weight was 0.57 + 0.05 g for males and 0.43 + 0.10 g for females. The cerebral and cerebellar mean lengths of 3.14 + 0.04 cm and 1.34 + 0.04 cm for males, 6.26 + 0.10 cm and 3.80 + 0.32 cm for females were observed. The cerebrum, cerebellum and olfactory bulb account for 70%, 12% and 6% of the total brain weight in males and 64%, 13% and 4% in the females respectively. The mean brain lengths were 5.63 + 0.07 cm and 6.26 + 0.1 cm for males and females respectively. There were significant differences in the body and olfactory bulb weights and also, in the whole brain and cerebral lengths between the males and females. In our present research, the ratios of 0.01 for males and 0.006 for females were observed. This suggests a relatively low brain weight in the ruminants. The olfactory bulb in the male is larger than that in the females. Females in turn have longer brain dimension than the males. Cerebellum has no sex variation both in weight and in length.

Este estudio se llevó a cabo para registrar los parámetros morfométricos del cerebro de grasscutters machos y hembras. Diez grasscutters sanos (5 machos y 5 hembras) fueron utilizados en este estudio. La media de peso del cerebro fueron 9,80 +/- 0,50 g y 10,27 +/- 0,45 g para los machos y hembras respectivamente. El peso medio del bulbo olfatorio fue 0,57 +/- 0,05 g para los machos y 0,43 +/- 0,10 g para las hembras. La longitud media del cerebro y del cerebelo fue de 3,14 +/- 0,04 y 1,34 cm +/- 0,04 cm para los machos, y 6,26 +/- 0,10 cm y 3,80 +/- 0,32 cm para las hembras, en las muestras observadas. El cerebro, cerebelo y el bulbo olfatorio representaron un 70%, 12% y el 6% del peso total del cerebro en machos y 64%, 13% y 4% en las hembras, respectivamente. La media de las longitudes del cerebro fueron 5,63 +/- 0,0 y 6,26 cm +/- 0,1 cm para los machos y hembras respectivamente. Hubo diferencias significativas en el peso del cuerpo y el bulbo olfatorio, y también en la longitud total del cerebro de machos y hembras. En nuestra actual investigación, los índices de 0,01 para los machos y de 0,006 para las hembras fueron observados. Esto sugiere un peso relativamente bajo en el cerebro de rumiantes. El bulbo olfatorio en los machos es mayor que en las hembras. A su vez, las hembras presentan una dimensión cerebral mayor que los machos. El cerebelo no tuvo variación según el sexo tanto en peso como en longitud.

Studies on effects of lactose on experimental Trypanosoma vivax infection in Zebu cattle. 2. Packed cell volume.

The ability of intravenously administered lactose in normal saline to prevent a decline in packed cell volume (PCV) during experimental trypanosomosis was studied in Zebu cattle. During the lactose infusion period, the PCV was stable up to Day 5 post-infection (p.i.) in a lactose-infused group, compared to that in an uninfused group in which the PCV dropped significantly (P < 0.05) as shown by the values of cumulative percentage change. Furthermore the mean rate of change in PCV was significantly (P < 0.05) higher in the uninfused group relative to the lactose-infused group during the same period. While the PCV fell markedly in the lactose-infused group a day after lactose infusion was stopped (Day 13 p.i.), subsequent PCV values were significantly (P < 0.05) higher compared to those in the uninfused group, up to the end of experiment on Day 17 p.i. However the mean rates of change in PCV did not vary significantly (P > 0.05) between the groups during the period in which lactose infusion was stopped. The mean levels of parasitaemic waves and parasitaemia were higher, more prolonged and more frequent in the lactose-infused group. It was inferred that the lactose was able to prevent an early onset of anaemia in the Trypanosoma vivax-infected Zebu cattle.

Toxicological screening of lyophilized extract of some Nigerian wild mushrooms in mice.

Mushrooms are macrofungi widely consumed as food. However, many mushrooms rot away in the wild because of fear of toxicity. Therefore, lyophilized aqueous extracts of 6 mushroom species collected from Zaria, Nigeria and taxonomically identified as Chlorophyllum molybdites, Panaeolus subalteatus, Macrolepiota procera, Leucopaxillus albissmus, Hygrophoropsis aurantiacus and Pholiota aurea were screened for toxicity in mice. Lyophilized aqueous extract of each of these mushrooms was administered to three groups of 3 mice intraperitoneally (i.p.) at doses of 100, 1000 and 10, 000 mg kg(-1), respectively. Another group of three mice given distilled water served as control. The mice were examined for clinical signs of toxicity over a period of 72 h and pathological examinations conducted on dead animals. The severity of clinical signs, onset of death and pathological lesions were dose dependent. Death occurred within 10 min in all the mice dosed at 10,000 mg kg(-1) with the lyophilized extracts of all the mushrooms screened, with the exception of that of H. aurantiacus, which produced death 21-23 h post administration. This result showed that all the screened mushrooms, including the popular edible M. procera were found toxic. Therefore, since all the mushrooms screened were found toxic, it is recommended that extreme caution should be exercised in their consumption. Furthermore, in view of the regional differences in the toxicity of mushrooms, there is the need to screen more wild mushrooms found in Nigeria for toxicity. This will boost mushroom mycophagy, reduce poisoning incidence and reduce wastage of edible mushrooms in the wild.

Studies on effects of lactose on experimental Trypanosoma vivax infection in Zebu cattle. 1. Plasma kinetics of intravenously administered lactose at onset of infection and pathology.

Lactose in normal saline was administered intravenously to a group of Zebu cattle infected with Trypanosoma vivax to determine the blood plasma kinetics at onset of an experimental infection and its ability to protect tissues against damage as part of preliminary studies to determine its suitability for use in the treatment of trypanosomosis. Significantly (P < 0.01) higher lactose concentrations were observed in the T. vivax-infected bulls at 30 min and 1 h (P < 0.05) post-infection (p.i.) and by 4 h p.i. the plasma lactose remained above the level prior to infusion, after which it fell slightly below the pre-infusion level in the uninfected group. Calculated pharmacokinetic parameters revealed delayed excretion of lactose in the T. vivax-infected group soon after infection. The total body clearance (Cl(B)) was significantly (P < 0.05) reduced. The biological half-life (t1/2), elimination rate constant (k(el)) and apparent volume of distribution (V(d)) were relatively decreased (P > 0.05) as a result of the T. vivax infection. Retention of lactose in the plasma was attributed to decreased plasma clearance. It is suggested that the presence of trypanosomes in circulation rather than organic lesions could have been responsible for the delay observed in the excretion of lactose. At 12 weeks p.i., when the experiment was terminated, the group infected and given lactose infusion (despite higher parasitaemia) had no gross or histopathological lesions in the brain, spleen, lymph nodes, heart, kidneys, liver and testes. However, the group infected but not infused with lactose were emaciated, had pale mucosae, watery blood, general muscular atrophy, serous atrophy of coronary fat and other adipose tissue, hepatomegaly, splenomegaly, swollen and oedematous lymph nodes, all of which are suggestive of trypanosomosis. Histopathological lesions included narrowing of Bowman's space and hypercellularity of glomerular tufts in the kidneys with the mean glomerular tuft nuclear indices (GTNs) in the group significantly higher (P < 0.01) than the mean GTNs of the lactose-infused and control bulls. Degenerative changes occurred in the myocardium, spleen, testes and epididymides. The tesicular and epididymal lesions are indicative of male reproductive dysfunction.

Aetiology and prevalence of canine anaemia in Zaria: a review of 2139 cases observed at the Veterinary Teaching Hospital of the Ahmadu Bello University, Zaria, Nigeria (1990-2003).

An investigation was conducted at the Ahmadu Bello University Veterinary Teaching Hospital (ABUVTH) between January, 1990 and September, 2003 to determine the aetiology and prevalence of canine anaemia in Zaria, Nigeria. Out of the 5278 mongrel dogs presented during the period 1990-2003, 2139 (40.5%) were found to be anaemic, with packed cell volume (PCV) values ranging from 7 to 36%. The clinical signs presented by these dogs include: Pale mucous membranes, weakness, depression, anorexia/inapettence and reduced activity. About 50 dogs (about 1%) with helminths and haemoparasitic infestations had high PCV values (37-40%) without clinical presentation of anaemia or disease. Most of the dogs with anaemia (n = 2016 or 94.2%) had parasitic infestations. About 1580 (about 74%) of the anaemic cases, attributed to parasitic infestations occurred between May and October. A few dogs (n = 55, 2.6%) had anaemia due to poor nutrition, while 68 (3.2%) had anaemia with unknown cause. The public health significance of the parasites reported in this study is discussed.