Prevalence of bovine tuberculosis in Jigawa State,northwestern Nigeria

We determined the prevalence of bovine tuberculosis in Jigawa State, northwestern Nigeria using the comparative intradermal tuberculin test in 22 herds consisting of 922 cattle with overall and individual prevalence of 1.08% (10/922) and 45.45% (10/22) obtained, respectively.     

Prevalence of bovine campylobacteriosis in indigenous cattle of three states in Nigeria

Summary A survey of bovine campylobacteriosis in breeding bulls and cows was carried out in the states of Kaduna, Kano and Borno. Six hundred and eighty nine cattle composed of 585 and 104 breeding bulls and cows respectively were sampled.Campylobacter fetus subsp.venerealis was isolated from 12 bulls whileCampylobacter fetus subsp.fetus was isolated from three of them. Campylobacter fetus subsp.fetus was isolated fromfour cows while Campylobacter fetus subsp.venerealis was isolated from one cow. The overall prevalence of campylobacteriosis in the three states was 2.9% (20/689). The result of the study identifiesCampylobacter fetus subsp.venerealis as the agent of enzootic infertility in Nigeria and suggests that it may be a significant problem.

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Resumen Un estudio sobre la prevalencia de campilobacteriosis en reproductores machos y hembras bovinos se llevó a cabo en los estados de Kaduna, Kano y Borno. Seiscientos ochenta y nueve animales, compuestos de 585 y 104 toros reproductores y vacas respectivamente, fueron examinados.Campylobacter fetus subsp.venerealis fue aislado de 12 toros, mientras queC. fetus subsp.fetus, se aisló de tres de ellos.C. fetus subsp.fetus se aisló de cuatro vacas, mientras queC. fetus subsp.venerealis, se aisló de una vaca. La prevalencia general de campilobacteriosis en los tres estados fue de 2.9% (20/689). El resultado de este estudio identifica alC. fetus subsp.venerealis, como el agente de infertilidad enzoótica en Nigeria, y sugiere que este puede ser un problema significativo.

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Résumé Une enquête sur la campylobactériose bovine a été menée sur du bétail reproducteur dans les états de Kaduna, Kano et Borno au Nigeria. Elle a porté sur 689 bovins dont 585 taureaux et 104 femelles.C. foetus subsp.veneralis a été isolé sur 12 taureaux etC foetus subsp.foetus sur 3 d'entre eux.C. foetus subsp.foetus a été décelé sur 4 vaches tandis queC. foetus subsp.foetus ne 1'a été que sur une seule. L'a prévalence globale de la maladie dans les 3 états représente 2,9 p. 100, soit cas sur 689 examinés. Cette enquête a permis d'identifierC. foetus subsp.veneralis comme étant responsable d'une infertilité enzootique au Nigeria. Elle indique que cette affection peut constituer un important problème.

     

Prevalence and risk factors of mycobacterial infections in farm and trade cattle in southwestern Nigeria

We evaluated the prevalence of mycobacterial infections (i.e., Mycobacterium bovis and non-tuberculous mycobacteria [NTM]) and their associated risk factors among cattle herds and trade cattle in southwestern Nigeria. Through cross-sectional study design, cattle herds from three locations were screened using the single intradermal comparative cervical tuberculin test based on two diagnostic standards; more than 4 mm (? 4 mm) and more than 2 mm (? 2 mm) cut-off points. Abattoir study involved screening trade cattle for tuberculous lesions. Overall, 515 cattle from 45 herds were screened. Using >?4 mm, animal level and herd prevalence of 11.7 and 46.7% were recorded, respectively. Applying the ? 2 mm cut-off, animal level and herd prevalence increased to 31.1 and 60.0%, respectively. Significantly, using the ? 2 mm cut-off, cattle in medium size herds/extensive management system (OR?=?1.6; 95% CI 1.1–2.5) and Sokoto Gudali (OR?=?2.3; 95% CI 1.4–3.8) were more at risk of being positive reactors, while Rahaji (OR?=?0.3; 95% CI 0.1–0.7) breeds of cattle and cows in the peri-urban area (OR?=?0.4; 95% CI 0.2–0.9) were less at risk of being positive reactors. Again, M. avium reactor of 21.7% was observed. In the abattoir, 1797 cattle were examined with 126 lesions suggestive of tuberculosis (TB). Culture/molecular analyses confirmed 2.2% M. bovis and 0.9% NTM infections. Risk factors associated with bovine TB among trade cattle were sex (OR?=?4.0; 95% CI 1.2–13.5) and age (OR?=?0.3; 95% CI 0.1–0.9). We confirm 11.7% prevalence of mycobacterial infections among populations of cattle screened with breed and herd size being major risk factors.     

Prevalence of bovine tuberculosis in pastoral cattle herds in the Oromia region,southern Ethiopia

A cross-sectional study of bovine tuberculosis (BTB) was conducted in pastoral cattle herds in southern Ethiopia, from February to August 2008 using the comparative intradermal tuberculin test. The prevalence of BTB and the risk factors for having positive reactor herds were assessed in four pastoral associations in two districts of southern Ethiopia, namely Goro-Dola with 242 cattle in 16 herds and Liben with 231 cattle in 15 herds. A herd was considered positive if there was at least one reactor animal in a herd. The test results were interpreted based on the Office Internationale des Epizooties recommended 4-mm and a recently suggested 2-mm cut-off. The apparent individual animal prevalence of tuberculin reactors was 5.5% (95% confidence interval (CI), 4.0–8.0%) and 7.0% (95% CI, 5.0–10.0%), whereas the true prevalence estimate was 4.4% (95% CI, 0.8–8.0%) and 6.1% (95% CI, 2.6–9.5%), when using the 4-mm and the 2-mm cut-offs, respectively. The overall herd apparent prevalence of tuberculin reactor animals was 41.9% (95% CI, 24.9–60.9%) and 48.4% (95% CI, 30.2–66.9%) with the 4-mm and 2-mm cut-offs, respectively. A positive tuberculin test was associated with the age of animals and the main drinking water sources during dry seasons. In order to investigate the public health risks and the epidemiological importance of BTB in the area, we recommend to include other livestock species (camels and goats) as well as humans in future studies.     

Age-dependent patterns of bovine tuberculosis in cattle

Bovine tuberculosis (BTB) is an important livestock disease, seriously impacting cattle industries in both industrialised and pre-industrialised countries. Like TB in other mammals, infection is life long and, if undiagnosed, may progress to disease years after exposure. The risk of disease in humans is highly age-dependent, however in cattle, age-dependent risks have yet to be quantified, largely due to insufficient data and limited diagnostics. Here, we estimate age-specific reactor rates in Great Britain by combining herd-level testing data with spatial movement data from the Cattle Tracing System (CTS). Using a catalytic model, we find strong age dependencies in infection risk and that the probability of detecting infection increases with age. Between 2004 and 2009, infection incidence in cattle fluctuated around 1%. Age-specific incidence increased monotonically until 24–36 months, with cattle aged between 12 and 36 months experiencing the highest rates of infection. Beef and dairy cattle under 24 months experienced similar infection risks, however major differences occurred in older ages. The average reproductive number in cattle was greater than 1 for the years 2004–2009. These methods reveal a consistent pattern of BTB rates with age, across different population structures and testing patterns. The results provide practical insights into BTB epidemiology and control, suggesting that targeting a mass control programme at cattle between 12 and 36 months could be beneficial.     

Prevalence of bovine tuberculosis in cattle in different farming systems in the eastern zone of Tanzania

The prevalence of bovine tuberculosis (BTB) infection in cattle was investigated in pastoral and intensive production systems in the eastern zone of Tanzania. The prevalence of BTB infection as determined by single comparative intradermal tuberculin test (SCITT) was 1.3%, whereas the non-specific infection prevalence was 6%. In the pastoral sector, the prevalences were 1 and 7%; under intensive systems, they were 2 and 6% for BTB and non-specific infections, respectively. The prevalences were significantly higher in the intensive than pastoral production systems. However, the prevalence of BTB infection was higher in the small-scale (3%) than in other production systems (0.6-1.1%). Non-specific infections were lowest in the small-scale dairy sector (4%) than in other dairy-production systems (6-11%).Out of 143 herds tested, 10 and 28% of herds in the intensive systems (small, medium and large farms) and 17 and 88% of the herds in the extensive system (pastoral farms) had both BTB and non-specific infections, respectively.     

Lactation performance of the White Fulani cattle in Southern Nigeria

Summary Data on the lactation performance of the White Fulani cattle in Southern Nigeria were analysed. The first lactation yield over a mean lactation period of 230.68 ± 2.25 days averaged 810.89 ± 32.11 kg, while overall lactation yields averaged 1018.28 ± 18.10 kg over a mean lactation period of 249.67 ± 3.28 days. The year of calving was a significant source of variation in both first and overall lactation yields but season of calving had no significant effect on lactation yield. Lactation yield and length were positively correlated. Heritabilities of 0.26 ± 0.06 and 0.51 ± 0.05 were obtained for lactation yield and length respectively from half-sib analysis while the repeatability estimates were 0.32 ± 0.04 and 0.21 ± 0.04 respectively. There was little difference in performance of the White Fulani cattle under the humid conditions of Southern Nigeria compared to the semi-arid conditions of the north.

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Potencialidad Para La Produccion De Leche Del Ganado White Fulani En El Sur De Nigeria

Resumen Se analizaron datos de lactación del ganado White Fulani en el Sur de Nigeria. La primera lactación sobre un período medio de 230·68 ± 2·25 días promedió 810·89 ± 32·11 kg, mientras que el producto total de la lactación general promedió 1018·28 ± 18·10 kg sobre un período medio de 249·67 ± 3·28 días. El año de parición se constituyó en una feuente significativa de variación sobre la producción de la primera lactación y de la producción general, pero la estación de parición no tuvo un efecto significativo sobre el producto lácteo. La producción láctea y la duración de la misma se correlacionaron positivamente. Se obtuvieron heredabilidades de 0·26 ± 0·06 y 0·51 ± 0·05 en cuanto a la producción láctea y duración de la misma respectivamente mediante análisis medio hermana, mientras que los estimativos de repetibilidad furon 0·32 ± 0·04 y 0·21 ± 0·04 respectivamente. Hubo pequeñas diferencias en el comportamiento productivo del ganado White Fulani bajo condiciones húmedas en el Sur de Nigeria comparado al rendimiento obtenido en condiciones semiáridas del Norte.

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Performances Laitieres Du Betail White Fulani Dans Le Sud Nigeria

Résumé On a analysé les données du rendement laitier du bétail White Fulani dans le sud Nigéria. Le rendement de la première lactation sur une période de lactation de 230,68±2,25 jours est en moyenne de 810,89 ± 32,11 kg, tandis que la lactation totale produit en moyenne 1018,28 ± 18,10 kg sur une péroide moyenne de lactation de 249,67 ± 3,28 jours. L'année de vêlage est une source importante de variation pour les rendements de la première et de la lactation globale, mais la saison du velage n'a qu'un effet insignifiant sur le rendement. La durée et le rendement de la lactation sont corrélés positivement. Des kératabilités de 0,26 ± 0,06 et 0,51 ± 0,05 ont été respectivement obtenues pour le rendement et la durée de la lactation à partir des analyses half-sib (demi soeur), tandis que les estimations de répétition sont de 0,32 ± 0,04 et 0,21 ± 0,04 respectivement. Il n'y a que peu de différence des performances du bétail White Fulani dan l'environnement humide du Sud-Nigéria par rapport aux conditions semi-arides du Nord.

     

Prevalence of bovine cysticercosis in slaughtered cattle in Iran

Bovine cysticercosis is an important food safety issue and can cause economic loss. A cross sectional study on Taenia saginata cysticercosis was carried out in slaughtered cattle in Iran in order to determine the infection rate during a three-years period, from 2005 to 2007. A total of 4,534,105 cattle were examined by routine meat inspection. The results showed that 11,410 cattle (0.25 %) were infected with Cysticercus bovis; among those 1,041 carcasses (0.02%) were condemned. In such carcasses the metacestodes caused extensive damage in the vicinity of cysts in infected cattle. The rejected carcasses had an average of 410 thousands USD loss annually.     

Comparative assessment of postmortem inspection and immunochromatographic techniques for the detection of bovine tuberculosis in slaughter cattle in Nigeria

Animals with tuberculosis pose some risks to humans, especially in developing countries of the world. In this study, postmortem inspection (PMI) and immunochromatographic assay (ICA) techniques were compared for the detection of bovine tuberculosis (BTB) in slaughter cattle in Enugu State, Nigeria using culture as the gold standard. A cross-sectional study was conducted from January–June, 2011 on animals presented at four purposively selected slaughterhouses in the study area, involving a total of 500 randomly selected animals. Blood samples were collected from the jugular veins of selected animals and serum samples harvested for ICA. Thorough PMI was carried out and tissue samples from the lung, liver, intestine, and lymph nodes were collected, with or without lesions for culture; from the animals examined, culture detected 11 positive cases giving a prevalence rate of 2.2 %, whereas PMI detected 22 positive cases including 7 (out of the 11) positive cases detected by culture, giving a prevalence rate of 4.4 %. Fifteen of the cases detected as positive by PMI were negative by culture. Therefore, the sensitivity and specificity of PMI were 64 and 97 %, respectively. ICA detected 59 positive cases including 10 of the 11 positive cases detected by culture, hence, a prevalence rate of 11.8 %. Forty-nine of the cases detected as positive by ICA were negative by culture. Hence, the sensitivity and specificity of ICA were 91 and 90 %, respectively. In conclusion, the performance of ICA was found sufficiently high to support its use in BTB surveillance and control in cattle in Enugu State, Nigeria.     

Prevalence of microfilariae in cattle at slaughter in Zaria, Nigeria

Skin snips and blood taken from 372 randomly selected slaughtered cattle in Zaria, Nigeria were examined for microfilariae. A total of 293 (78.8%) skin snips and 218 (58.6%) blood samples were positive for microfilariae. Two types of microfilariae, identified as Onchocerca armillata, with a percentage prevalence of 64%, and O. gutturosa with a prevalence of 40% were isolated from the skin. The blood microfilariae were identified as those of Setaria labiatopapillosa.     

Prevalence of bovine tuberculosis in slaughtered cattle identified by nested-PCR in abattoirs from two dairy areas of Ecuador

Bovine tuberculosis (bTB) is a chronic granulomatous disease that primarily affects lung tissue and lymph nodes (LN) in cattle, with economic impact on their productivity. Furthermore, it is potential zoonoses that may cause public health hazard. In this study, we evaluated the presence of bTB in two abattoirs: Cayambe and Pelileo countries located in the Ecuadorian provinces of Pichincha and Tungurahua, respectively. In total, 578 cattle were sampled (Cayambe 271 and Pelileo 307): 1,156 LN and 578 lung tissue samples were collected to apply in vitro culture and nested-PCR, respectively. The results determined a total apparent prevalence of 4.33 %, with 4.06 % at Cayambe’s abattoir and 4.56 % at Pelileo’s abattoir. Additionally, the Bayesian analysis showed a total true prevalence of 2.51 %, with 89.7 % of sensitivity and 97.6 % of specificity. The risk factors were evaluated by the use of simple logistic regressions with and without the random effect of places of origin. Associations of the origin of cattle in the selected slaughterhouses were found. The results showed an efficient method for the detection of bTB, which could identify a large number of infected animals, and the usefulness of lung tissue samples for early diagnosis of the disease was demonstrated in this study.     

Prevalence of bovine tuberculosis in slaughter cattle in Kenya: a postmortem, microbiological and DNA molecular study

A study to determine the presence and prevalence of bovine tuberculosis in slaughter cattle in Kenya was carried out in two abattoirs from July to November 2009. Routine postmortem meat inspection was performed on a subpopulation of 929 cattle selected randomly from among 4,984. Carcases were inspected for gross tuberculous lesions which were then examined for acid-fast bacilli, (AFB), cultured for isolation of mycobacteria and the isolates characterised by DNA molecular analysis. Of the carcases examined, 176 (18.95?%, 95?% CI) had lesions suggestive of tuberculosis. AFB were observed in 63/176 of the lesioned cattle and mycobacteria were isolated from 64 of them. The isolates were identified as Mycobacterium bovis (19/64), Mycobacterium tuberculosis, (2/64) and mycobacteria other than tuberculosis (43/64). The prevalence of M. bovis by molecular analysis was 2.05?% (95?% CI). This study documents for the first time the presence of bovine tuberculosis among slaughter cattle in Kenya. There is therefore a need to formulate and implement control programmes in order to minimise transmission among animals and to humans. Isolation of M. tuberculosis from cattle underscores the risk tuberculous humans pose to animals.     

Post-mortem examination and laboratory-based analysis for the diagnosis of bovine tuberculosis among dairy cattle in Ecuador

Veterinary inspection in slaughterhouses allows for the detection of macroscopic lesions reminiscent of bovine tuberculosis, but the presence of Mycobacterium bovis must be confirmed by laboratory methods. This study aimed at comparing the performances of the standard diagnostic tools used to identify M. bovis in tissue specimens sampled from suspicious animals. During a two years period, 1390 cattle were inspected at the Machachi abattoir in the Mejia canton - Ecuador. A total of 33 animals with granulomatous lesions were detected, representing 2.33% (16/687) and 2.42% (17/703) animals examined in 2007 and 2008, respectively. Ninety-four tissue specimens were sampled and screened for the presence of mycobacteria. Acid-fast bacilli were identified in one third of the suspicious cattle (11/33) and suggestive microscopic lesions in 27.3% (9/33) of the samples examined by direct microscopy and histopathology, respectively. Culturing on Stonebrink medium and 16S-rRNA-based polymerase chain reaction (PCR) yielded 36.4% (12/33) and 27.3% (9/33) of positives, respectively. Compared to culture, other diagnostic procedures displayed a lower sensitivity, with 56.5% for PCR, and 43.5% for direct microscopy and histopathology; however, the specificity was higher (94.4% for PCR and microscopy, and 97.2% for histopathology). We conclude that reliable post-mortem laboratory testing either requires the combination of a set of available diagnostic tools or necessitates the development of improved new-generation tools with better sensitivity and specificity characteristics.     

Prevalence of bovine parvovirus infection in Ontario dairy cattle.

Studies were conducted to determine prevalence and dynamics of bovine parvovirus (BPV) infection. Dairy cows from 29 randomly selected herds in southwestern Ontario were tested twice, one year apart, for the presence of hemagglutination inhibition (HI) antibodies against BPV. Fifty-one percent of 1141 cows tested had BPV-HI titers > 1:32. One year later, the seroprevalence was 83% in 1131 cows from the same farms. The herd mean seroprevalence was 49% and 86% for the year-1 and year-2 samples, respectively. Evidence of BPV infection was found in 96% (27/28) of herds in year-1 and 100% of herds in year-2. A comparison of titers from 716 cows tested twice showed evidence of frequent BPV infection. Sixty-two percent of 326 animals selected in a systematic manner from 40 Guelph area dairy farms had BPV-HI titers > 1:32. The herd mean seroprevalence was 64% Two herds had no animals with titers above the critical titer (1:32) while in one-quarter of the herds all animals exceeded the critical titer.     

Prevalence of bovine herpesvirus-1 in the Belgian cattle population

The national bovine herpesvirus 1 (BHV-1) seroprevalence (apparent prevalence) in the Belgian cattle population was determined by a serological survey that was conducted from December 1997 to March 1998. In a random sample of herds (N=556), all cattle (N=28 478) were tested for the presence of antibodies to glycoprotein B of BHV-1. No differentiation could be made between vaccinated and infected animals, because the exclusive use of marker vaccines was imposed by law only in 1997 by the Belgian Veterinary Authorities. Twenty-one percent of the farmers vaccinated continuously against BHV-1.

In the unvaccinated group, the overall herd, individual-animal and median within-herd seroprevalences were estimated to be 67% (95% confidence interval (CI)=62–72), 35.9% (95% CI=35.0–36.8) and 33% (quartiles=14–62), respectively.

Assuming a test sensitivity and specificity of 99 and 99.7%, respectively, the true herd, individual-animal and median within-herd prevalence for the unvaccinated group of herds were estimated to be 65, 36 and 34%, respectively. The true herd prevalence for dairy, mixed and beef herds were respectively, 84, 89 and 53%; the true individual-animal prevalence for those types of herds were, respectively, 35, 43 and 31%; whereas, the true median within-herd prevalences were 36, 29 and 38%.     

Prevalence of contagious bovine pleuropneumonia (CBPP) in northern Nigeria

An abattoir study on the prevalence of contagious bovine pleuropneumonia (CBPP) in five cattle-producing states of Nigeria from 1988 to 1997 was carried out. A total of 1,936,015 slaughtered cattle was examined for characteristic CBPP lung lesions. The overall lesion-based prevalence of CBPP was 0.29% (95% CI 0.24, 0.35). The prevalence varied significantly (P<0.05) by state but not across the years. A total of 279 CBPP outbreaks occurred and overall vaccination coverage was only 9.7%, both varied over the years and across the states. The reasons for inadequate vaccination coverage for CBPP as well as the need for re-establishment of a national CBPP control programme are suggested.