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Background: Brucellosis is a world-wide extended zoonosis that causes a grave problem in developing economies. Animal vaccination and diagnosis are essential to control brucellosis, and the need for accurate but also simple and low-cost tests that can be implemented in low-infrastructure laboratories has been emphasized. Methodology: We evaluated bovine, sheep, goat and swine lateral flow immunochromatography assay kits (LFA), the Rose Bengal test (RBT) and a well-validated protein G indirect ELISA (iELISA) using sera of Brucella culture-positive and unvaccinated brucellosis free livestock. Sera from cattle vaccinated with S19 and RB51 brucellosis vaccines were also tested. Finally, we compared RBT and LFA using sera of white Fulani cattle of unknown bacteriological status from a brucellosis endemic area of Nigeria. Results and conclusions: Although differences were not statistically significant, RBT showed the highest values for diagnostic sensitivity/specificity in cattle (LFA 96.6/98.8; RBT 98.9/100; and iELISA 96.6/100) and the iELISA yielded highest values in sheep (LFA, 94.0/100; RBT, 92.0/100; iELISA, 100/100), goats (LFA 95.7/96.2; RBT, 97.8/100; iELISA, 100/100) and pigs (LFA, 92.3/100; RBT, 92.3/100; iELISA 100/100). Vaccine S19 administered subcutaneously interfered in all tests but conjunctival application minimized the problem. Although designed not to interfere in serodiagnosis, vaccine RB51 interfered in LFA and iELISA but not in the RBT. We found closely similar apparent prevalence results when testing the Nigerian Fulani cattle by RBT and LFA. Although both RBT and LFA (showing similar diagnostic performance) are suitable for small laboratories in resource-limited areas, RBT has the advantage that a single reagent is useful in all animal species. Considering these advantages, its low cost and that it is also useful for human brucellosis diagnosis, RBT might be a good choice for resource-limited laboratories. [ABSTRACT FROM AUTHOR]

This study evaluated the prevalence, hematological and some biochemical alterations in Brucella seropositive Muturu breed of cattle which may change the narratives of multi-disease tolerance of the breed. Sera from 33 Muturu cattle herds chosen by snow ball sampling were screened for Brucella antibodies with modified Rose Bengal test (RBT) supported with the cELISA. Eighteen (18) seropositive samples matched to18 sero-negatives, with regard to age and sex of the animals and chosen by simple random sampling, were analyzed for hematological and biochemical changes, following standard procedures. Individual seroprevalence of 38% and 10% were recorded with the RBT and cELISA respectively, while herd seroprevalence of 52% was recorded with the RBT and none with the cELISA. Seropositivity to brucellosis was significantly associated with farm origin (OR = 16.67; 95%CI = 1.56-153.85; p = 0.019). There was significantly lower packed cell volume (PCV) (p = 0.048) and absolute eosinophil count (p = 0.006), and significantly higher absolute lymphocyte count (p = 0.014) in the seropositive than the negative Muturu cattle. In addition, plasma fibrinogen (p < 0.001), serum albumin (p = 0.037), urea (p = 0.001) and cholesterol (p = 0.032) were significantly lower while serum globulin (p = 0.004), alanine aminotransferase (ALT) activity (p = 0.012) and bilirubin (p = 0.012) were significantly higher in the seropositive than sero-negative Muturu cattle. No significant variations were observed in the rest of the parameters assayed. These findings suggest that Muturu cattle are apparently susceptible to brucellosis and experience active organism-host interactions with resultant clinicopathological effects and therefore could be passive harbingers of Brucella for other animals as well as humans., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

Introduction: a cross-sectional study was conducted to determine the seroprevalence and associated factors of brucellosis and Q-fever among cattle in a rural setting in Oyo State, Nigeria., Methods: one hundred and fourty nine serum samples (24 males; 125 female) from 16 cattle herds were collected and screened. The Rose Bengal Plate test (RBPT) and competitive Enzyme-Linked Immunosorbent Assay (cELISA) were used for brucellosis while indirect Enzyme-Linked Immunosorbent Assay (iELISA) was used for Q-fever. Further, a checklist was used to collect data on cattle sampled. Data were analyzed using STATA 12., Results: serum analysis revealed that 11.4% (17/149) and 6.7% (10/149) were seropositive by RBPT and cELISA respectively for brucellosis, while 23.5% (35/149) were seropositive by iELISA for Q-fever. A significant association was detected between cattle age (OR=27.7; 95% CI: 2.34-449.86), herd size (OR=10.53; 95% CI: 1.85-60.53) and seropositivity to Brucella infection. Also, there was a significant association between breed (OR=6.69; 95% CI: 1.7-28.74), herd size (OR=4.25; 95% CI: 1.31-13.85) of cattle and seropositivity to Coxiella burnetii infection. Importantly, the only significant associated factor to cattle herd seropositivity to Brucella and C. burnetii infections was the method of handling aborted foetuses., Conclusion: the study revealed that brucellosis and Q-fever are prevalent among cattle in the study area. Thus, there is a need for further studies to provide better insight into the epidemiology of both diseases and particularly Q-fever. This becomes imperative in the study area and generally in Nigeria given the dearth of information about the diseases in pastoralist communities who are at grave risk of infection at the human-animal-ecosystem interface., Competing Interests: The authors declare no competing interests., (Copyright: Simeon Idowu Cadmus et al.)

Bovine brucellosis is endemic in Nigeria; however, limited data exist on nationwide studies and risk factors associated with the disease. Using a cross-sectional sero-epidemiological survey, we determined the prevalence of and risk factors for brucellosis in slaughtered cattle in three geographical regions of Nigeria. Serum samples from randomly selected unvaccinated cattle slaughtered over a period of 3 years (between December 2010 and September 2013) from northern, southern and south-western Nigeria were tested for antibodies to Brucella abortus using the Rose Bengal test. Data associated with risk factors of brucellosis were analysed by Stata Version 12. In all, 8105 cattle were screened. An overall seroprevalence of 3.9% (315/8105) was recorded by the Rose Bengal test, with 3.8%, 3.4% and 4.0% from the northern, southern and south-western regions, respectively. Bivariate analysis showed that cattle screened in northern Nigeria were less likely to be seropositive for antibodies to Brucella spp. than those from south-western Nigeria (odds ratio = 0.94; 95% confidence interval: 0.73-1.22). However, logistic regression analysis revealed that breed ( p = 0.04) and sex ( p £ 0.0001) of cattle were statistically significant for seropositivity to Brucella spp. The study found that brucellosis was endemic at a low prevalence among slaughtered cattle in Nigeria, with sex and breed of cattle being significant risk factors. Considering the public health implications of brucellosis, we advocate coordinated surveillance for the disease among diverse cattle populations in Nigeria, as is carried out in most developed countries.

Limited data are available on the risk factors responsible for the occurrence of brucellosis amongst different cattle production systems in Nigeria despite its significant impact on livestock production. Consequently, a cross-sectional study was conducted to determine the prevalence of bovine brucellosis in three cattle production systems in Yewa Division of Ogun State, south-western Nigeria. A total of 279 blood samples (sedentary = 88; transhumance = 64; trade = 127) were examined for antibodies to Brucella sp. using the Rose Bengal test (RBT) and competitive enzyme-linked immunosorbent assay (cELISA). Overall, 24 (8.6%) and 16 (5.7%) of the animals tested seropositive for Brucella using RBT and cELISA, respectively. The herd seroprevalences based on RBT and cELISA were 31.6% and 15.8%, respectively. The results using cELISA reveal higher seroprevalence in the trade cattle (7.9%; confidence intervals [CI] = 3.2% - 12.6%) and those in a sedentary system (5.7%; CI = 0.9% - 10.5%) than in cattle kept under a transhumant management system (1.6%; CI = 1.5% - 4.7%). Age (> 3 years; p = 0.043) and breed (Djali; p = 0.038) were statistically significant for seropositivity to brucellosis based on cELISA, but sex (female, p = 0.234), production system (trade and sedentary; p = 0.208) or herd size (> 120; p = 0.359) was not. Since breeding stock is mostly sourced from trade and sedentary cattle, it is important that routine serological screening should be conducted before introducing any animal into an existing herd.

In this study, milk and blood samples collected simultaneously from 532 trade cows to be slaughtered at Bodija abattoir, Ibadan (southwestern, Nigeria) were examined for antibodies to Brucella using the milk ring test (MRT) and the rose bengal test (RBT). Overall, 18.61% of the milk samples were positive according to the MRT, while 9.77% of the serum samples were positive according to the RBT. The difference was highly significant (Chi-square value 16.33; P < 0.05); only 32 (6.02%) of the samples were positive for both tests. The Red Bororo breed of cattle and the White Fulani had the highest positive rates, namely 20.93% and 11.69% for the MRT and RBT respectively. No conclusion can be drawn about sensitivity because we do not know the true status of the animals tested. It is, however, obvious that although the MRT and RBT are 1st-line screening tests for brucellosis in cows in some countries, their lack of specificity is of concern. Therefore, the requirement for other confirmatory tests that are more specific should be considered for control and eradication of the disease, especially in Nigeria.