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Background: African swine fever (ASF), a highly contagious fatal acute haemorrhagic viral disease of pigs currently has no treatment or vaccination protocol and it threatens the pig industry worldwide. Recent outbreaks were managed by farmers with ethnoveterinary preparations with various claims of effectiveness., Results: We identified 35 compounds using GC-MS protocol and ASF virus (NIG 99) was significantly reduced by some extracts and fractions of the plant. However, the plant was poorly extracted by water and cytotoxicity was found to be a major problem with the use of the plant since its extracts also reduced the primary cells used in the assay., Conclusion: It is confirmed that the plant has antiviral potentials against ASF virus and farmers' claims seem to have certain degree of veracity, but finding the best means of exploring the potential of the plant while reducing its cytotoxic effect in-vitro and in-vivo will be necessary.

African swine fever remains the greatest limitation to the development of the pig industry in Africa, and parts of Asia and Europe. It is especially important in West and Central African countries where the disease has become endemic. Biosecurity is the implementation of a set of measures that reduce the risk of infection through segregation, cleaning and disinfection. Using a 122-sow piggery unit, a financial model and costing were used to estimate the economic benefits of effective biosecurity against African swine fever. The outcomes suggest that pig production is a profitable venture that can generate a profit of approximately US$109,637.40 per annum and that an outbreak of African swine fever (ASF) has the potential to cause losses of up to US$910,836.70 in a single year. The implementation of biosecurity and its effective monitoring can prevent losses owing to ASF and is calculated to give a benefit-cost ratio of 29. A full implementation of biosecurity will result in a 9.70% reduction in total annual profit, but is justified in view of the substantial costs incurred in the event of an ASF outbreak. Biosecurity implementation is robust and capable of withstanding changes in input costs including moderate feed price increases, higher management costs and marginal reductions in total outputs. It is concluded that biosecurity is a key to successful pig production in an endemic situation., (© 2011 Blackwell Verlag GmbH.)

African swine fever (ASF) has had significant economic and social impact in Nigeria since 1997. However, there has been no effective national response to bring it under control. In this report, we confirm that ASF is still prevalent and widespread in Nigeria. Results from both serosurveillance and virological analyses indicated that ASF is present in most of the agro-ecological zones of the country. Nine per cent (9%) of serum samples and 48% of tissue samples were positive for ASF virus antibody and genome, respectively. Areas with high pig-related activities (marketing, consumption and farming) have higher prevalences compared with areas with less pig activities. Farm-gate buyers, marketing systems and transport of untested pigs within the country assist with the circulation of the virus. Only by putting in place a comprehensive routine surveillance and testing system, reorganizing the market and transportation systems for pigs, implementing on-farm bio-security protocols and considering the option of compensation will it be possible to achieve a significant reduction in ASF prevalence in Nigeria.

The methanol and aqueous extracts of Boswellia dalziellii stem bark showed broad spectrum inhibiting activity against bacteria, both Gram-positive and Gram-negative, and fungi.

Antigenic diversity within a collection of 18 isolates of Dermatophilus congolensis from different Continents was examined by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and by Western blotting with sera from cattle with clinical dermatophilosis using whole cell extracts obtained by three methods and one extract of extracellular products of D. congolensis. One of the methods involving the release of a lysostaphin-solubilized protein (LSP) of whole cells of D. congolensis revealed a number of discrete and easily-identifiable bands in SDS-PAGE which were found suitable for characterizing protein patterns and was, therefore, subsequently used for a comparative analysis of the proteins of all the D. congolensis isolates. Six electropherotypes (ET) of D. congolensis were identified among the 18 isolates using the protein profiles based on the presence of four protein bands at Molecular weights (MW) 62, 28, 17.4 and 16.4 kDa. The ETs were found among isolates from different animal species and from different sources with ET1 consisting of three bovine and two equine isolates; ET2, two bovine and three ovine isolates; ET3, two bovine isolates; ET4, two bovine isolates; ET5, one bovine and one ovine isolates and ET6, two bovine isolates. Immunoblotting of the extracts of D. congolensis isolates with sera from cattle with clinical dermatophilosis infection demonstrated protein bands of MW ranging from 9 kDa to 188 kDa. Sera from chronic dermatophilosis infection demonstrated a 28 kDa protein which was immunodominant in the LSP extracts of all the 18 isolates of D. congolensis tested while sera from mild infections demonstrated mainly the 62 kDa protein in the same extracts. However, many protein bands were demonstrated in surface membrane (TSMP) and extracellular protein extracts with sera from only mildly infected animals. The protein patterns observed in all isolates of D. congolensis revealed global antigenic similarities and distinct differences among isolates which could not be associated with either geographic, climatic or host factors. Also sera from infected animals from endemic regions of dermatophilosis could not differentiate isolates of D. congolensis. This suggests the possibility that such sera must have come from animals that had been infected by a multitude of D. congolensis strains present in the herd environment and strains an animal could have come across during the 'ritual' annual cross-country migration of the cattle herds.

The yeast, Cryptococcus neoformans, was found in apparently healthy birds at the Jos Wildlife Park and Zoo in Jos, Nigeria. Cryptococcus neoformans var neoformans was isolated from feces of four captive bird species. Five isolates belonged to serotype A while two were serotype D. Serotype A of C. neoformans was isolated from a white face duck (Dendrocygna viduata), eagle owl (Bubo africanus cinerascene) and peacock (Pavo cristatus). The other two (serotype D), were isolated from a spotted eagle owl.

A serotype differentiation of the encapsulated yeast Cryptococcus neoformans is described using creatinine dextrose bromothymol blue thymine (CDBT) medium. On CDBT medium C. neoformans serotype D grew as bright red colonies, turning the medium a bright orange after five days incubation at 28 degrees C. C. neoformans serotype A grew as pale colonies with no apparent colour effect on the medium. Serotypes B and C caused a slight greening of the medium. The reaction of the four serotypes of C. neoformans on CDBT medium is considered useful in the differentiation of the closely related serotype A and D.

The agar-gel precipitation test (AGPT) was compared with Enzyme Immunoassay (EIA) for the detection of Chlamydia trachomatis, 164 women being screened for chlamydial antibodies and antigens in their sera and in endocervical specimens, respectively. The AGPT showed good correlation with EIA in the 164 paired sera and endocervical specimens, resulting in 27 (16.5%) and 22 (13.4%) positive results, respectively (P greater than 0.05). The overall sensitivity of the AGPT compared to EIA was 86.4% (19 of 22), and the specificity was 94.4% (134 of 142).

In a serological examination of 710 serum samples collected from human volunteers in Plateau State, Nigeria, 128 (18.0pc) had leptospiral antibody titres of 1:100 and above. The prevalence of antibodies to individual serovars were: hardjo 28 (21.9pc), pomona 18 (14.1pc), canicola 17 (13.3pc), grippotyphosa 15 (11.7pc), pyrogenes 13 (10.2pc), icterohaemorrhagiae 12 (0.4pc) and autumnalis 8 (6.3pc). There was no statistical difference in the prevalence rate of leptospirosis in the different local government areas (p greater than 0.05; X2). Among the occupational groups examined, the abattoir workers were particularly at risk with a prevalence rate of 29.5pc. A leptospiral variant of strain Hardjoprajitno was also isolated from the midstream urine of an abattoir worker who was apparently healthy. The isolation of Leptospira interrogans serovar hardjo in man is the first such report in Nigeria.

A case of eye infection in a heifer was reported with bilateral blindness, cornea opacity, excessive lachrymation and nasal discharge. Treatment with 6-10 drops of a 10% solution of levamisole resulted in a complete recovery, a total of 127 adult Thelazia rhodesii being recovered from the eyes.

Serum samples obtained from 1.537 cattle in the 14 local government areas (LGAs) of Plateau State of Nigeria were screened for the presence of leptospiral antibodies using 13 serovars in a modified microscopic agglutination test (MAT). Two hundred and twenty-two (14.4 p.100) of the cattle tested had leptospiral antibody titres of 1:100 or higher to one or more of the test antigens. The prevalence rates of antibodies to individual serovars were: hardjo (35.6 p.100), pomona (11.7 p.100), pyrogenes (11.7 p.100), canicola (9.5 p.100), grippotyphosa (7.7 p.100), bratislava (5.9 p.100), icterohaemorrhagiae (5.9 p.100), ballum (4.5 p.100), autumnalis (3.6 p.100), bataviae (2.3 p.100) and tarassovi (1.8 p.100). The serological prevalence of bovine leptospirosis in the various local government areas of Plateau State of Nigeria differed significantly (P less than 0.05; X2).

The reverse single radial immunodiffusion technique was used to detect Dermatophilus congolensis antibody in sera collected from animals previously infected to varying levels with D congolensis. Ammonium sulphate and trichloroacetic acid extracts of five different strains of D congolensis obtained from different geographical locations were used as antigens. All the extracts showed variations in their sensitivities in detecting D congolensis antibody in the various serum samples. Multiple antibodies were detected by some extracts while some showed negative antibody reaction to all extracts. Two extracts also showed cross-reactions with the serum from an animal that was infected by Nocardia species. Trichloroacetic acid extracts of all the strains were found to be more active serologically, detecting antibody in more sera and giving sharper and clearer reactions than ammonium sulphate extracts.

In a pilot survey to compare the relative prevalence of three diseases in apparently healthy White Fulani Zebu (WFZ) cattle slaughtered in Nigeria, sera from 80 randomly selected animals with no significant gross lesions on ante mortem and post mortem inspection were examined for antibodies to Brucella abortus, Dermatophilus congolensis and bovine leukaemia virus. Of the samples screened, 5.0, 8.8 and 2.0% showed serological evidence for brucellosis, cutaneous streptothricosis and bovine leukosis respectively.

A lyophilised T1 vaccine was produced by direct lyophilisation of a 72-hour broth culture to which 10% sterile sucrose solution was added. Each vial contained 2 ml to make a total of 10 doses when reconstituted. Each ml of the product contained an average of 109 colony forming units of the organism. When injected at the tip of the tail or subcutaneously behind the shoulder of 2,000 zebu and 1,0000 Ndama cattle, no outward reactions were observed. 12 zebu cattle were vaccinated and challenged 6 months later by direct contact with artificially infected cattle for 4 months. All the animals were completely protected against the disease.

Glutaraldehyde-treated whole cell antigens (GA.WcA) of Dermatophilus congolensis induced in guinea pigs immunological memory in contrast to cell wall antigens treated similarly (GA.CwA). However, GA.WcA could not induce a secondary response in animals primed with untreated WcA while GA.CwA on the other hand did stimulate a secondary response in animals primed with untreated CwA. Primary antibody production was induced by both GA.CwA and untreated CwA to a similar level in their respective hosts but it was the secondary response that was found similar in response to GA.WcA and untreated WcA. However, both untreated WcA and CwA induced primary and secondary antibody production in their respective hosts though these responses were considerably higher in guinea pigs given untreated CwA. This study showed that both untreated and GA-treated antigens of D. congolensis are capable of stimulating antibody production in guinea pigs but they differ in their levels of stimulation.

Sixty-one sera from animals that had contact with Dermatophilus congolensis were examined by comparing three serological methods; counterimmunoelectrophoresis, passive haemagglutination, and agar gel diffusion, and by using four different antigenic extracts of D congolensis. The counterimmunoelectrophoresis was the most satisfactory of the methods having been found to be specific and sensitive, easy to perform and suitable for screening large numbers of samples. It was also found to have a higher antibody detection rate (82.2 per cent) than the other methods thus making it suitable for seroepidemiological surveys. It was found to be capable of detecting multiple antibodies and also revealed dissimilarities among the different antigenic extracts. The cellular antigens of D congolensis were found to detect antibody in more sera than the extracellular antigen; the cell wall extract proved to be the most satisfactory of all, detecting antibody from the largest number of sera compared to the other extracts in all the three serological tests.

A serological survey on dermatophilosis was carried out amongst sheep and goats in Kaduna State of Nigeria. Sera were obtained from slaughter animals and from sheep kept on an isolated ranch. The percentage of seropositive animals was 28.0 in slaughter sheep, 0.0 in sheep kept on the ranch, and 23.2 in slaughter goats. The high prevalence of D. congolensis antibodies among small ruminants compares well with the level of prevalence reported of cattle of cattle and calls for a concerted government effort for the control of the disease.

Rabbits were infected with Dermatophilus congolensis and tested for humoral immune response by indirect haemagglutination and for cell-mediated immune response to crude antigens of D. congolensis. Lymphocyte transformation and macrophage migration inhibition assays were used as in vitro correlates of cell-mediated immune response while cutaneous delayed hypersensitivity was used in vivo. Endo-antigen and whole cell antigen were found to significantly induce cell-mediated immune response. In contrast, humoral responses were found to be more significantly induced by exo-antigen. A biphasic immune response was revealed by the lymphocyte transformation test.

Passive haemagglutination and agar gel diffusion tests were used to detect specific antibody to Dermatophilus congolensis antigens in serum and milk of eight streptothricosis infected Friesian milking cows. All the sera and milk samples showed the presence of antibody but titres were higher in sera. Precipitating antibodies were detected only in three sera. A possible implication of this finding is discussed with respect to passive immunity in the young calves from infected dams.