Short communication: Passive shedding of Mycobacterium avium ssp. paratuberculosis in commercial dairy goats in Brazil

Abstract

Goat farming is a low-cost alternative to dairy production in developing countries. In Brazil, goat production has increased in recent years due in part to the implementation of programs encouraging this activity. Mycobacterium avium ssp. paratuberculosis (MAP) is the causative agent of paratuberculosis, a disease that causes chronic granulomatous enteritis in ruminants, but MAP transmission dynamics are still poorly understood in goats. In a previously published study of our research group, 10 dairy goat farms (467 animals) from Minas Gerais state were analyzed for MAP detection; 2 fecal cultures and 11 milk samples tested positive for MAP by conventional PCR and were confirmed by sequencing. Because no clinical signs were observed over 1 yr of monitoring, we hypothesized that these MAP-positive goats could be passive shedders. Thus, in the present study, 4 positive goats (4/13) from the previous study were purchased and feces and milk samples were collected for evaluation (twice, with an interval of 3 mo between tests) by culture of MAP, IS900 PCR, or both. All analyses were negative for MAP. At the last time point, blood samples were collected for ELISA, the animals were killed, and tissues collected for tissue culture and histopathology. At necropsy, no macroscopic lesions related to paratuberculosis were observed. Similarly, no histological changes were observed and MAP in samples stained by Ziehl-Neelsen was not detected. These animals were characterized as potential passive shedders with upward contamination of the teat canal by MAP. This is the first report of the passive shedding phenomenon in goats in Brazil and it highlights the importance of identifying these animals for control programs and to ensure the quality of dairy products.

Physical-chemical and microbiological quality of milk and cheese of goats fed with bidestilated glycerin

“…The increase in goat milk production and processing that has occurred in recente years is mainly due to new food trends (Barlowska et al, 2018). Goat rearing is a low cost alternative for dairy production in underdeveloped and developing countries (Schwarz et al, 2017). There is a demand from the consumer to buy cheese made by traditional methods.…”

Paratuberculosis in dairy goat flocks from southern Spain: risk factors associated with seroprevalence

“…7 8 Goat production has increased all over the world, mainly in developed countries, due to the low input required and the fact that it is a source of dairy products ideal for people with an allergy to cow's milk. 9 Globally, Europe is the third largest continent for dairy goat farming (14.40 per cent), with Spain, Greece and France accounting for 70 per cent of the dairy goat population and more than 80 per cent of goat milk production in Europe. Andalusia, located in southern Spain, is one of the European regions with the highest goat census and the highest milk production, with 520,165 dairy goats and 206,114 litres of milk produced.…”

Physicochemical and sensory properties of goat cheeses and their fatty acid profile in relation to the geographic region of production

“…Goat farming is a low‐cost alternative to dairy production in developing countries (Schwarz et al . ). Today's consumers expect much more of food than simply the capacity to satisfy hunger.…”

“…This is mainly due to new dietary trends, as well as to a lack of production limits on goats' milk, which were in force for cows' milk in the European Union until 31 March 2015. Goat farming is a low-cost alternative to dairy production in developing countries (Schwarz et al 2017). Today's consumers expect much more of food than simply the capacity to satisfy hunger.…”