Prevalence of rotavirus A infection and the detection of type G3P[11] strain in ruminants in Yobe state,Nigeria

Rotaviruses have a worldwide distribution and the infection is associated with diarrhea in young of ruminants as well as children. However, limited data exist on its prevalence and types in Yobe state, Nigeria. Detection of rotavirus A and types in ruminant population in Yobe state was the aim of the study. A total of 470 diarrheic fecal samples were collected and tested for rotavirus and types using serology and molecular techniques respectively. A prevalence rate of 2.98% (14/470) was found in the three species with specific rates of 2.9% (6/202), 3.8% (6/158), and 1.8% (2/110) in goat, sheep, and cattle respectively. The prevalence rates of 3.6% (12/331), 1.2% (1/84), and 1.8% (1/55) were for those aged < 1–3, 4–6, and 7–9 months old, respectively, while 4.9% (9/185) and 1.7% (5/285) were in males and females respectively. Rotavirus genes VP7 and VP4 were detected in 2 (14.3%) out of the 14 ELISA-positive samples while deduced amino acid sequences of the major variable regions revealed the genes to belong to types G3P[11] strain. Significant association was found between the infection and sex (P < 0.05) unlike in the species and age groups of the ruminants. The circulation of rotavirus virus in ruminants and type G3P[11] in cattle has been confirmed in the study. Hence, there is a need for continuous surveillance, awareness campaign, and assessment of the economic losses and public health implications of rotavirus infection in Nigeria.

     

Molecular confirmation of candidate Hsp70 gene associated with heat tolerance in BC3F2 advanced backcross lines and their phenotypic resemblance with recurrent chilli Kulai

ABSTRACT

Domestic production of chilli in Malaysia is insufficient which accounted for 52% self-sufficiency level. Poor performance of local varieties under high temperatures above 42°C is one of the major factors affecting chilli production. This study was conducted with the objective of introgress heat-tolerant gene (Hsps) from AVPP0702 donor into Kulai using marker-assisted backcrossing. A total of 68 SSR markers, including Hsp linked markers that showed polymorphism between the parents were used to assess the generation of backcrossing; BC1F1, BC2F1, BC3F1 and BC3F2 and the average RPG percentage of the recurrent parent was found to be 81, 90, 95 and 97%, respectively. The pattern of Hsp expression in the backcross generations was similar to the donor parent (upregulated with more than 4-fold increase). Twelve improved heat tolerant chilli lines were developed. Most of the morphological and agronomical traits were recovered in the selected improved heat-tolerant genotypes from Kulai such as plant height, number of days to 50% flowering, number of fruits, fruit length and total fruit yield per plant. Improved high-yielding heat-tolerant chilli lines showed tolerance to high temperature as well as did not express any negative effect on agronomic traits in comparison with Kulai variety.     

<Emphasis Type="Italic">Mycobacterium bovis</Emphasis>, but also <Emphasis Type="Italic">M. africanum</Emphasis> present in raw milk of pastoral cattle in north-central Nigeria

Using deletion typing technique, five mycobacteria isolated from unpasteurised milk samples from cows in north-central Nigeria were characterized as Mycobacterium bovis (n = 4) and M. africanum (n = 1). This report emphasizes that transmission between the animal and human reservoir is a serious threat in Nigeria.     

Suppression of immune response to sheep red blood cells in rats experimentally infected with Trypanosoma brucei gambiense

A direct haemagglutination assay for antibodies to sheep red blood cells (SRBC) was used to assess the response of rats infected with Trypanosoma brucei gambiense. Whereas uninfected rats showed an efficient primary and secondary immune response to SRBC, trypanosome-infected rats displayed depressed antibody response starting about six days after infection. Infected rats failed to respond to a challenge dose of SRBC given 14 days after infection while uninfected control animals responded with an increased level of antibody production. These observations showed that T. b. gambiense infection inhibited both primary and secondary immune response to SRBC in rats. The result of this experiment is very important with regard to serological methods used to detect increasing levels of antibody production for diagnosis of diseases caused by bacterial and viral pathogens. In a concurrent trypanosome infection such increasing antibody levels would not be observed, leading to inaccurate diagnosis. Thus trypanosomiasis infection should be excluded under field conditions before the value of a serological diagnosis can be fully utilized.