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The aim of this study was to evaluate fear condition responses in sheep and goat and to relate this to the neuroarchitecture of their amygdala. Forty adult sheep (Uda breed) and 40 adult goats (Red Sokoto breed) were fear-conditioned by associating the sound of a car horn (neutral stimuli) with water spray (aversive stimuli) and the fear response was determined by direct observation of the behavior of the sheep and goats and measuring their flight distances and escape time. Eight groups were studied, each comprising of 10 animals (five sheep and five goats). Goats and sheep were tested alternately in the morning of every day of the week for three consecutive weeks, in which 4 days was used for habituation and 3 days for testing. Histologically, neurons in the central and basolateral complex of the amygdala were studied and analyzed using Nissl and golgi staines. Behaviorally, goats elicited an active avoidance response expressed as flight with concomitant intense flight distances (p < .001) compared to sheep. Although, sheep had larger brain parameters, it showed attenuated basolateral amygdala cytoarchitecture consistent with reduced fear perception and response. Goats had significantly more densely distributed pyramidal and spiny stellate neurons in the basolateral amygdala while sheep showed more non-pyramidal and aspiny neurons. These results provide interesting practical perspectives on how adaptions in the amygdala coincides with alterations in fear conditioning in domestic animals and may be the basis for the higher incidence of the sheep in automobile accidents than goats in developing countries especially Africa.

We hyposthesized that henna staining could provide an alternative to eosin when used as a counterstain to hematoxylin for understanding basic neurohistological principles. Therefore, this study was aimed at investigating the suitability of henna as counterstain to hematoxylin for the demonstration of the layer stratification and cellular distribution in the brain tissue. Henna stained nervous tissue by reacting with the basic elements in proteins via its amino groups. It stained the neuropil and connective tissue membranes brown and effectively outlined the perikarya of neurons with no visible nuclei demonstrating that it is an acidic dye. Henna as a counterstain to hematoxylin demonstrated reliability as a new neurohistological stain. It facilitated identification of cortical layer stratification and cellular distribution in brain tissue sections from Wistar rats. This was comparable to standard hematoxylin and eosin staining as morphological and morphometrical analyses of stained cells did not show significant differences in size or number. This study presents a method for staining with henna and demonstrates that although henna and eosin belong to different dye groups (anthraquinone and xanthenes, respectively) based on their chromophores, they share similar staining techniques and thus could be used interchangeably in neurohistology.

Leishmaniasis is a major health problem and it is estimated that 12 million people are currently infected. A vaccine which could cross-protect people against different Leishmania spp. would facilitate control of this disease as more than one species of Leishmania may be present. In this study the ability of a DNA vaccine, using the full gene sequence for L. donovani gamma glutamyl cysteine synthetase (γGCS) incorporated in the pVAX vector (pVAXγGCS), and a protein vaccine, using the corresponding recombinant L. donovani γGCS protein (LdγGCS), to protect against L. major or L. mexicana infection was evaluated. DNA vaccination gave transient protection against L. major and no protection against L. mexicana despite significantly enhancing specific antibody titres in vaccinated infected mice compared to infected controls. Vaccination with the LdγGCS protected against both species but only if the protein was incorporated into non-ionic surfactant vesicles for L. mexicana. The results of this study indicate that a L. donovani γGCS vaccine could be used to vaccinate against more than one Leishmania species but only if the recombinant protein is used.

Vernonia amygdalina and Annona senegalensis, two plants used by local/smallholder livestock farmers in Nigeria as anthelmintic were screened for in vitro anthelmintic activity using Haemonchus contortus eggs. The extract of V. amygdalina did not show any significant activity at concentrations up to 11.2mg/ml. The extract of A. senegalensis showed significant (P

The spinal cord of the adult African Giant Pouched rat was studied using the rapid Golgi technique in order to get further clarification on the morphology of the neuronal cell types based on soma size, shape, dendritic density and aborization. Two main types of cells were observed to characterize the dorsal grey horn: Type 1 cells are the islet cells which were distinguished by triangulated or globular- shaped soma with one thick “axoniform” primary dendrite bifurcating into a Y or T secondary branches indicative of local integrating functions. They resembled the pseudounipolar cells of the dorsal root ganglion and were predominant in the cervical segments. Type 2 cells were stalked cells with several dendrites and round or polygonal soma and these were predominant in the thoracic and lumbosacral segments. The ventral grey horn demonstrated multipolar neurons with dendritic arborization arranged in a radiating or tuft-like manner. Some cells had sparse dendrites while some other cells demonstrated unique ...

Preliminary investigation of the in vitro and in vivo efficacies of different extracts from the leaves of Vernonia amygdalina (VA), a plant widely used in Nigeria was evaluated in Balb/C mice infected with a laboratory strain of Leishmania major (L. major). The ability of the methanol, hexane and aqueous extracts of the plant to suppress the infection rate and its cytotoxicity on macrophages and L929 cells were determined in the in vitro study. The in vivo study evaluated time course of infection, lesion progression and the histopathology of cutaneous lesions, liver and spleen after inoculation with metacyclic promastigotes. Methanolic extract of VA containing high levels of flavanoids, was the most potent extract as it showed the highest suppression on infectivity and viability of intracellular amastigotes at a concentration lower than that which elicited cytotoxicity on macrophages. Treatment of infected mice with methanolic extract of VA showed delayed onset of disease with a significant reduction in lesion size and attenuation of the histopathological outcome characterised by intact epidermis and less tissue destruction in skin, spleen and liver. In conclusion, these results demonstrate that VA has potent antileishmanial properties which warrants further investigation into the immunological mechanism.

A 6-year retrospective study (2000–2005) of animals slaughtered at the Zango abattoir in Zaria, Kaduna State, Nigeria was carried out to determine disease conditions encountered in slaughtered animals. Records kept at the abattoir were analysed. A total of 69,307 cattle, 3,820 goats and 1,763 sheep were slaughtered for the period under study. Of the 69,307 cattle slaughtered for the period, 22,459 (32.41%) were males and 46,848 (67.59%) were females, while 1,763 sheep were slaughtered comprising of 506 (28.70%) males and 1,257 (71.30%) females, and 3,820 goats made up of 1,212 (31.73%) males and 2,608 (68.27%) were females. The major disease and/or pathological conditions were helminthosis (fascioliasis, haemonchosis and paramphistomosis) 16.20%, Streptothricosis 4.15%, Pericarditis 2.20%, liver cirrhosis 2.08%, abscesses 1.04%, pneumonia 0.14%, nephritis 0.05% and Contagious Bovine Pleuropneumonia, Tuberculosis and Nocardiosis 0.01% each. Out of the 15,075 infected organs, 13,314 (88.38%) were partially salvaged while 1,751 (11.6%) whole organs were condemned. A total of 1,239 pregnant cows, 221 pregnant ewes and 637 pregnant does were slaughtered, representing a foetal wastage of 2.65% for cattle, 17.58% for sheep and 24.43% for goats. The result of this study apart from serving as an indicator of field disease condition also demonstrates cases of serious losses in production due to slaughter of pregnant animals especially for sheep and goats.