Isolation nontuberculous mycobacteria and histopathological changes in lymph nodes collected at the abattoir in cattle reactive-positive to tuberculin dermal test

Background: The Mycobacterium tuberculosis complex causes a variety of diseases; in bovine, the common pathogen is M. bovis which is considered zoonotic. A separate group of mycobacteria, much less known, is "non-tuberculous mycobacteria (NTM) which are also infectious for animals and humans. The Mexican Official Norm (NOM-ZOO-031-1995) regulates M. bovis in cattle, but not NTM species, even though this last type of microorganisms has a confounding effect for the diagnosis of bovine tuberculosis. The objective of the study was to isolate and identify the NTM of bovine lymph nodes condemned in the slaughterhouse, to characterize the histological lesions in these tissues and to correlate bacteriological and postmortem findings with the antemortem skin test of the tuberculin. Results: Mycobacteria were isolated from 54/528 (10.2%) of the lymph nodes; 29/54 (53.7%) of these isolates were identified as M. bovis and 25/54 (46.2%) as NTM; 3 bacteriological cultures were discarded due to contamination with fungi and in one case it was not possible to identify the species. Granulomatous and pyogranulomatous inflammation were observed in 6/21 (28.6%) and 7/21 (33.3%) of the NTM-positive lymph nodes, respectively. Necrosis and mineralization were only found in 6/21(28.6%) of the lymph nodes. The species of NTM associated with granulomatous lymphadenitis were M. scrofulaceum, M. triviale, M. terrae and M. szulgai, while those causing pyogranulomatous lesions were M. szulgai, M. kansasii, M. phlei, and M. scrofulaceum. Conclusions: Considering the increase of mycobacterial infections in humans worldwide, the idetification of NTM that inducing Tuberculosis-like lesions in abattoir inspection is the first step to investigate the livestock-human-wildlife-environment interactions with especially focus on transmission dynamics.

Influence of temperature on prevalence of health and welfare conditions in pigs: time-series analysis of pig abattoir inspection data in England and Wales

The prevalence of many diseases in pigs displays seasonal distributions. Despite growing concerns about the impacts of climate change, we do not yet have a good understanding of the role that weather factors play in explaining such seasonal patterns. In this study, national and county-level aggregated abattoir inspection data were assessed for England and Wales during 2010–2015. Seasonally-adjusted relationships were characterised between weekly ambient maximum temperature and the prevalence of both respiratory conditions and tail biting detected at slaughter. The prevalence of respiratory conditions showed cyclical annual patterns with peaks in the summer months and troughs in the winter months each year. However, there were no obvious associations with either high or low temperatures. The prevalence of tail biting generally increased as temperatures decreased, but associations were not supported by statistical evidence: across all counties there was a relative risk of 1.028 (95% CI 0.776–1.363) for every 1 °C fall in temperature. Whilst the seasonal patterns observed in this study are similar to those reported in previous studies, the lack of statistical evidence for an explicit association with ambient temperature may possibly be explained by the lack of information on date of disease onset. There is also the possibility that other time-varying factors not investigated here may be driving some of the seasonal patterns.

Fasciola hepaticainfections in cattle and the freshwater snailGalba truncatulafrom Dakhla Oasis, Egypt

Infection byFasciolaspecies was investigated in seven districts of Dakhla Oasis, Egypt, through abattoir inspection of cattle livers for adult worms and sedimentation of faecal samples from local cattle to detectFasciolaeggs. In addition, lymnaeid snails collected from the study area were examined microscopically for developmental stages ofFasciolaspp. Abattoir inspection revealed that 51 out of 458 cattle livers (11.1%) contained adult flukes, which were identified morphologically asFasciola hepatica.Examination of the cattle faecal samples revealed that 142 out of 503 (28.2%) containedFasciolaeggs. The collected snails, identified asGalba truncatulaandRadix natalensis,showed larval stages ofFasciolain 71 out of 731 (9.7%)G. truncatula, whileR. natalensisshowed no infection. Specific duplex polymerase chain reaction (PCR) targeting the mitochondrialcox1gene ofF. hepaticaandFasciola giganticawas carried out on DNA extracted from pooled infected snails and adult worms. TheF. hepaticasize amplicon (1031 bp) was obtained from both the infectedG. truncatulaand the adult worms isolated from cattle livers from different districts. The amplicon sequences were identical to the published sequences ofF. hepaticamitochondrialcox1gene. In conclusion, the zoonotic importance ofFasciolainfection and appropriate hygienic measures must be taken into consideration in Dakhla Oasis, Egypt.

Prevalence of Fascioliasis in Cattle Slaughtered in Sokoto Metropolitan Abattoir, Sokoto, Nigeria

The prevalence of fascioliasis in cattle slaughtered in the Sokoto metropolitan abattoir was investigated. Faeces and bile samples were collected and processed using formal ether concentration technique. Gross lesions from 224 out of 1,313 slaughtered cattle were randomly selected and examined. Out of the 224 cattle examined, 95 (42.41%) were males and 129 (57.59%) were females. Out of 95 male cattle examined, 27 (28.42%) were infected and out of 129 females 35 (27.13%) were infected. Based on breed, infection rates were 31 (31.0%), and 31 (25.2%) for breeds of Sokoto Gudali and Red Bororo respectively. No infection was recorded in White Fulani breed. Lesions observed were more in males than in females and more in Red Bororo than in Sokoto Gudali. Overall, prevalence of infection with Fasciola was 27.68%. There was no statistically significant association between infection and breed and between infection and sex of the animals sampled (P>0.05). Regular treatment of all animals with an effective flukicide, as well as snail habitat control, tracing source of animals, public enlightenment about the disease, proper abattoir inspection, adequate and clean water supply to animals, and payment of compensation of condemned tissues and organs infested with the parasite by government were suggested.