Struggling to improve farm biosecurity: Do free advice and subsidies hit the target?

Contribution of herd management, biosecurity, and environmental factors to the risk of bovine tuberculosis in a historically low prevalence region

Eradication of bovine tuberculosis (bTB) in certain historically low-prevalence regions remains elusive. A complete characterisation of the husbandry practices, biosecurity, and environment where farms are located is crucial to implement targeted in-farm risk mitigation protocols. Here, a detailed survey performed in 94 dairy cattle farms located in Navarra, a low-prevalence region of Spain between 2016 and 2020 was carried out. Data on 73 biosecurity, farm-, and environmental-level factors potentially associated with the risk of bTB occurrence were evaluated using an ordinal logistic regression model: farms were classified based on their prevalence index, a score linked to each farm to account for the severity and recurrence of bTB cases: 22.3% of the farms had a score of 1, 21.3% a score of 2, 26.6% a score of ≥ 3, and 29.8% were negative herds. A statistically significant association between a higher prevalence index and the frequency of badger sightings along with the lease of pastures to sheep during Winter was identified. Farms that detected badgers on a monthly to daily basis in the surroundings and those that leased pastures for sheep flocks during Winter were four [odds ratio, 95% CI (4.3; 1.1-17.5)] and three (3.1; 1.0-9.9) times more likely to have the highest prevalence index, respectively (predicted probabilityprevalence index≥3 = 0.7; 95% CI 0.3-0.9). Conversely, farms that used a vehicle to transport animals from holdings to pastures were less likely (0.1; <0.1-0.3) to present higher levels of prevalence index compared with farms that used none (on foot). Results suggested that the combined effect of farm- and environmental-level risk factors identified here may be hampering disease eradication in Navarra, highlighting the need to implement targeted protocols on farms and grazing plots. An increased awareness of monitoring sheep and wildlife in direct or indirect contact with cattle herds in historically low bTB prevalence areas should be raised.

Situation Analysis and Recommendations for the Biosecurity Status of Dairy Farms in Punjab, India: A Cross-Sectional Survey

Farm biosecurity is an important herd management strategy to assure infection prevention and animal health. The present study aimed to evaluate the implementation of biosecurity measures on dairy farms in Punjab, India, using the standardized Biocheck.UGent™ scoring system. Convenience sampling was used to select 94 dairy farms, comprising both cattle and buffaloes, with a mean herd size of 74.8 animals. The study found that the mean external and internal biosecurity scores for the selected dairy farms were 45.4% and 43.7%, respectively. Among the subcategories, the highest external biosecurity score was observed for 'vermin control and other animals' (63%), and the highest internal biosecurity score was observed for 'adult cattle management' (76.6%). Whereas the lowest score for external biosecurity was observed for 'purchase and reproduction' (30.6%), and the lowest score for internal biosecurity was observed for 'health management' (33.6%). The overall mean biosecurity score of the present study was 44.8%, which was lower than the overall mean global score of 52%. The correlation analysis indicated a positive correlation between herd size and overall biosecurity scores, indicating that larger farms had, on average, higher biosecurity scores. Based on these results, it can be concluded that the implementation of biosecurity measures on dairy farms in Punjab needs improvement, especially in the subcategories of 'purchase and reproduction' and 'health management'. Further research to identify the factors influencing the implementation of biosecurity measures on dairy farms in the region is recommended.

Will we ever eradicate animal tuberculosis?

Two characteristics of the Mycobacterium tuberculosis complex (MTC) are particularly relevant for tuberculosis (TB) epidemiology and control, namely the ability of this group of pathogens to survive in the environment and thereby facilitate indirect transmission via water or feed, and the capacity to infect multiple host species including human beings, cattle, wildlife, and domestic animals other than cattle. As a consequence, rather than keeping the focus on certain animal species regarded as maintenance hosts, we postulate that it is time to think of complex and dynamic multi-host MTC maintenance communities where several wild and domestic species and the environment contribute to pathogen maintenance. Regarding the global situation of animal TB, many industrialized countries have reached the Officially Tuberculosis Free status. However, infection of cattle with M. bovis still occurs in most countries around the world. In low- and middle-income countries, human and animal TB infection is endemic and bovine TB control programs are often not implemented because standard TB control through testing and culling, movement control and slaughterhouse inspection is too expensive or ethically unacceptable. In facing increasingly complex epidemiological scenarios, modern integrated disease control should rely on three main pillars: (1) a close involvement of farmers including collaborative decision making, (2) expanding the surveillance and control targets to all three host categories, the environment, and their interactions, and (3) setting up new control schemes or upgrading established ones switching from single tool test and cull approaches to integrated ones including farm biosafety and vaccination.