Junaidu Kabir

Veterinary drug use in poultry farms and determination of antimicrobial drug residues in commercial eggs and slaughtered chicken in Kaduna State, Nigeria

Abstract The occurrence of veterinary drug residues in poultry products in Kaduna state was determined. Information on drug use was obtained from ten layer flocks weekly for 10 weeks. Two hundred commercial eggs, and 378 slaughtered chicken faeces were examined for antibacterial drug residues using a disc diffusion microbial inhibition test with Bacillus cereus ATCC 11778, and Micrococcus luteus ATCC 9341 respectively. All 10 farms used a drug at least once, nine used antibacterial drugs for either prophylaxis, therapy or both. None of the farms observed drug withdrawal period. Two eggs (1%) and 82 (21.8%) of the chicken faeces were positive. Broilers had a significantly higher incidence (33.1%) for antibacterial substances at slaughter (χ2,P

A large seroprevalence survey of brucellosis in cattle herds under diverse production systems in northern Nigeria

BackgroundThis study was carried out to investigate the status of brucellosis in cattle under various management systems in Adamawa, Kaduna and Kano states, northern Nigeria. Using multi-stage sampling, serum samples of 4,745 cattle from 271 herds were tested using the Rose-Bengal plate-agglutination test (RBPT) and positives were confirmed using a competitive enzyme-linked immunosorbent assay (c-ELISA).ResultsPrevalence estimates were calculated by adjusting for sampling weights and where possible for test sensitivity and specificity. Thirty-seven percent of all animals were RBPT positive, and after confirmation with c-ELISA the overall animal-level prevalence, adjusted for sampling weights, was 26.3% (95% CI, 22.1%-31.0%). Of the herds sampled, 210 (77.5%; 95% CI, 68.6%-84.5%) had at least one animal positive to both tests; this did not differ significantly between states (P = 0.538). Mean within-herd seroprevalence in positive herds was 30.2% (95% CI, 25.3%-35.1%) and ranged from 3.1% to 85.7%. Overall animal-level seroprevalences of 29.2% (95% CI, 22.5%-36.9%) n = 1,827, 23.3% (95% CI, 18.9%-28.3%) n = 1,870 and 26.7% (95% CI, 18.8%-36.7%) n = 1,048 were observed in Adamawa, Kaduna and Kano states, respectively (P = 0.496). A significantly higher seroprevalence was found in males (38.2%; 95% CI, 31.7%-45.2%) than in females (24.7%; 95% CI, 20.4%-29.5%) (P < 0.001) and in non-pregnant females (27.8%; 95% CI, 22.9%-33.5%) than in pregnant females (17.2%; 95% CI, 13.6%-21.5%) (P < 0.001). Seroprevalence increased with increasing age (P < 0.001), from 13.5% (95% CI, 8.9%-19.9%) in cattle <4 years to 35.0% (95% CI, 28.5%-42.3%) in cattle >7 years. Seroprevalence also varied between management systems (P < 0.001): pastoral systems 45.1% (95% CI, 38.6%-51.9%), zero-grazing systems 23.8% (95% CI, 6.8%-59.2%), agro-pastoral systems 22.0% (95% CI, 17.3%-27.8%), and commercial farms 15.9% (95% CI, 9.5%-25.5%). Seroprevalence did not differ significantly between breeds or lactation status.ConclusionThis is the first large study to assess the prevalence of bovine brucellosis over a wide geographic area of northern Nigeria, in a variety of management systems and using accurate tests. The seroprevalence of brucellosis was high, and higher than results of previous studies in northern Nigeria. The pastoral management systems of the traditional Fulanis may be encouraging the dissemination of the disease. Public enlightenment of the farmers about the disease, vaccination and appropriate national control measures are recommended.

'Prevalence and antimicrobial susceptibility of Listeria monocytogenes and methicillin-resistant Staphylococcus aureus strains from raw meat and meat products in Zaria, Nigeria.

The bacterial genera Listeria and Staphylococcus have been frequently isolated from food products and are responsible for a number of animal and human diseases. The aim of the study was to simultaneously isolate and characterize L. monocytogenes and Staphylococcus species from 300 samples of raw meat and meat products, to determine the susceptibility of the organisms to commonly used antimicrobial agents and to determine the presence of haemolysin A (hyl) virulence gene in L. monocytogenes and staphylococcal cassette chromosome mecA (SCCmec) gene in the Staph. aureus isolates using PCR. Of the 85 Listeria isolates tested, 12 L. monocytogenes were identified and tested for their sensitivity to 14 antimicrobial agents. All the 12 isolates (100%) were resistant to nine antimicrobial agents, but however sensitive to gentamicin. Only one isolate was found to harbour the hylA gene. Twenty‐nine isolates were confirmed as Staph. aureus by the Microbact 12S identification system and were all presumptively identified as methicillin‐resistant Staph. aureus species using oxacillin‐resistant Staph. aureus basal medium (ORSAB). The 29 Staph. aureus isolates were tested for their sensitivity to 16 antimicrobial agents, and 11 were resistant to methicillin. None of the 11 Staph. aureus isolates harboured the methicillin resistance, mecA gene.

Herd-level risk factors for Campylobacter fetus infection, Brucella seropositivity and within-herd seroprevalence of brucellosis in cattle in northern Nigeria.

Brucellosis and campylobacteriosis are economically important diseases affecting bovine reproductive efficiency in Nigeria. A questionnaire-based survey was conducted in 271 cattle herds in Adamawa, Kaduna and Kano states of northern Nigeria using multistage cluster sampling. Serum from 4745 mature animals was tested for Brucella antibodies using the Rose-Bengal plate test and positives were confirmed in series-testing protocol using competitive enzyme-linked immunosorbent assay. Preputial scrapings from 602 bulls were tested using culture and identification for Campylobacter fetus. For each disease, a herd was classified as positive if one or more animals tested positive. For each herd, information on potential managemental and environmental risk factors was collected through a questionnaire administered during an interview with the manager, owner or herdsman. Multiple logistic regression models were used to model the odds of herd infection for each disease. A zero-inflated Poisson model was used to model the count of Brucella-positive animals within herds, with the number tested as an exposure variable. The presence of small ruminants (sheep and/or goats) on the same farm, and buying-in of >3 new animals in the previous year or failure to practice quarantine were associated with increased odds of herd-level campylobacteriosis and brucellosis, as well as increased within-herd counts of Brucella-positive animals. In addition, high rainfall, initial acquisition of animals from markets, practice of gynaecological examination and failure to practice herd prophylactic measures were positively associated with the odds of C. fetus infection in the herd. Herd size of >15, pastoral management system and presence of handling facility on the farm were associated with increased odds, and gynaecological examination with reduced odds of herd-level Brucella seropositivity. Furthermore, the zero-inflated Poisson model showed that borrowing or sharing of bulls was associated with higher counts, and provision of mineral supplement with lower counts of Brucella-positive cattle within herds. Identification of risk factors for bovine campylobacteriosis and brucellosis can help to identify appropriate control measures, and the use of zero-inflated count model can provide more specific information on these risk factors.

Salmonella serovars and their distribution in Nigerian commercial chicken layer farms

Commercial poultry farms (n° 523), located in all the six regions of Nigeria were sampled with a view to generate baseline information about the distribution of Salmonella serovars in this country. Five different matrices (litter, dust, faeces, feed and water) were collected from each visited farm. Salmonella was isolated from at least one of the five matrices in 228 farms, with a farm prevalence of 43.6% (CI95[39.7–48.3%]). Altogether, 370 of 2615 samples collected (14.1%, CI95[12.8; 15.5%]) contained Salmonella. Considering the number of positive farms and the number of positive samples, it was evident that for the majority of the sampled farms, few samples were positive for Salmonella. With regard to the matrices, there was no difference in Salmonella prevalence among the five matrices considered. Of the 370 isolates serotyped, eighty-two different serotypes were identified and Salmonella Kentucky was identified as having the highest isolation rate in all the matrices sampled (16.2%), followed by S. Poona and S. Elisabethville. S. Kentucky was distributed across the country, whereas the other less frequent serovars had a more circumscribed diffusion. This is one of few comprehensive studies on the occurrence and distribution of Salmonella in commercial chicken layer farms from all the six regions of Nigeria. The relatively high prevalence rate documented in this study may be attributed to the generally poor infrastructure and low biosecurity measures in controlling stray animals, rodents and humans. Data collected could be valuable for instituting effective intervention strategies for Salmonella control in Nigeria and also in other developing countries with a similar poultry industry structure, with the final aim of reducing Salmonella spread in animals and ultimately in humans.

Characterisation and screening for antimicrobial substances of slaughtered cattle in Zaria, Nigeria.

The occurrence of antimicrobial drug residues in 500 routinely slaughtered cattle in Zaria, Nigeria, was determined. A microbial inhibition test with Micrococcus luteus ATCC9341 was used to test urine at the time of slaughter for the presence of antimicrobial substances. Thirty-seven (7.4%) of the urine samples were positive for antimicrobial substances. Positive cases were not distributed according to breed (P>0.05), but occurred significantly more in male cattle aged 3-9 years and in those with good body condition score (P<0.05). Thirty-eight cases, in the form of 16 different pathological conditions, were seen from visual inspection of carcasses. Lymphadenopathy was seen in 10 (23.7%) carcasses including one antimicrobial substances positive carcass. Dermatophilosis and emaciation constituted 15.8 and 13.2% of pathological conditions observed, respectively.

Evaluating a surveillance system: live-bird market surveillance for highly pathogenic avian influenza, a case study

Introduction Highly pathogenic avian influenza H5N1 was first reported in poultry in Nigeria in February 2006. The only human case that occurred was linked to contact with poultry in a live bird market (LBM). LBM surveillance was instituted to assess the degree of threat of human exposure to H5N1. The key indicator was detection of H5N1 in LBMs. We evaluated the surveillance system to assess its operations and attributes. Methods We used the US Centers for Disease Control and Prevention (CDC) updated guidelines for evaluating public health surveillance systems. We reviewed and analyzed passive surveillance data for HPAI (January 2006-March 2009) from the Avian Influenza National Reference Laboratory, and live bird market surveillance data from the Food and Agriculture Organization of the United Nations, Nigeria. We interviewed key stakeholders and reviewed reports of live bird market surveillance to obtain additional information on the operations of the system. We assessed the key system attributes. Results A total of 299 cases occurred in 25 (72%) states and the Federal Capital Territory (FCT). The system detected HPAI H5N1 virus in 7 (9.5%) LBMs; 2 (29%) of which were from 2 (18.2%) states with no previous case. A total of 17,852 (91.5%) of samples arrived at the laboratory within 24 hours but laboratory analysis took over 7 days. The sensitivity and positive predictive value (PPV) were 15.4% and 66.7% respectively. Conclusion The system is useful, flexible, complex and not timely, but appears to be meeting its objectives. The isolation of HPAI H5N1 virus in some of these markets is an indication that the markets are possible reservoirs of the virus in Nigeria. We recommend that the Federal Government of Nigeria should dedicate more funds for surveillance for HPAI as this will aid early warning and reduce the risk of a pandemic.

Seroprevalence of Coxiella Burnetti in Cattle and Its Risk Factors in Kaduna Metropolis, Kaduna State, Nigeria

Coxiellosis (Q fever) is a zoonosis of public health significance. This study was aimed at determining the seroprevalence and the risk factors associated with Coxiella burnetti infection in cattle in Kaduna metropolis, Nigeria. A total of 539 blood samples from 42 cattle farms in the four Local Government Areas (LGAs) of Kaduna metropolis were tested using enzyme linked immunosorbent assay (ELISA), in addition to application of structured questionnaires on the farmers. The total prevalence rate and herd prevalence rates obtained were 78 (14.5%) and 24 (57.1%) respectively. The sex based prevalence rates showed no significant difference between females(14.5%) and males(14.1%). Age of cattle was not significantly associated with infection (OR= 1.13, 95% CI, 0.69-1.86). Prevalence was significantly higher in the local breed of cattle (17.1%) than cross breed (1.3%) (P<0.05). The questionnaire analysis showed prevalence rate was higher in herds with no ectoparasite control(100%) than in herds with ectoparasite control(56.1%).Cleaning and disinfection of equipment after use was found to have a significantly protective effect (OR= 0.15, 95% CI 0.03- 0.79). The high prevalence rate of coxiellosis is of public health concern as this is a probable indicator of its presence in humans. It is also of importance as the disease can cause great economic loss among livestock population. A control programme involving good hygienic practices and public health education is recommended.

Seroprevalence of brucellosis and Q fever (Coxiellosis) in cattle herds in Maigana and Birnin Gwari agro-ecological zone of Kaduna State, Nigeria

A cross sectional study was conducted to determine the seroprevalence and risk factors of brucellosis and Q fever in cattle in Maigana and Birnin Gwari agro-ecological zone of Kaduna State, Nigeria. This study aimed at determining the significance of Brucella spp. and Coxiella burnetti infections in cattle. A total of 400 sera samples (139 from males and 261 from females cattle) were collected and screened for brucellosis using Rose Bengal Plate test (RBPT) and competitive enzyme linked immunosorbent assay (cELISA) for brucellosis and indirect enzyme-linked immunosorbent assay (iELISA) for Q fever. A structured questionnaire was used to collect data on the sampled animals from the study population. Data were analyzed to determine association and risk factors. Sera analysis revealed that, 18.5 and 6.8% were seropositive by RBPT and cELISA for brucellosis, while 6.2% was seropositive by iELISA for Q fever. A significant association was detected between cattle sex and sensitivity of RBPT for detecting Brucella. Meanwhile, a non-significant association was found between cattle age and breed with sensitivity of RBPT, cELISA, and iELISA. The study indicates that brucellosis and Q ever exist with high prevalence particularly among female cattle. This presents a serious public health problem, calling for greater awareness among stakeholders and for co-ordinated surveillance for the diseases among cattle populations in Nigeria.

Serosurvey of West Nile virus in household-reared pigeons in Bauchi metropolis, Nigeria

Background In Nigeria not much is known about West Nile virus (WNV) in pigeons. This study determined the involvement of household-reared pigeons in the circulation of WNV in Nigeria. Methods It was a cross-sectional study. Serological detection was done using competitive enzyme-linked immunosorbent assay and a pretested interviewer-administered questionnaire was used to collect information on risk factors related to WNV in households. Results From the156 households enumerated, 376 pigeon serum samples were collected and tested for antibodies. A total of 3.5% (13/376) of the pigeon sera were positive. Risk factors for WNV in households indicated that not having a blocked or stagnant gutter that is not flowing, and having mosquito nets at the windows and doors were found to be protective (OR=0.69, 95% CI, 0.21-2.29; OR=0.46, 95% CI, 0.14-1.56). Conclusions Household-reared pigeons contribute to the epidemiology of WNV. There is need for further studies in other species of birds, and education of the populace about its zoonotic transmission.