Mammary gland health of Santa Inês ewes at the drying and puerperium and evaluation of a dry-off terapy with gentamicin

Abstract

Mastitis represents an important health problem for Santa Inês breed, causing losses to the producer, due to loss of ewes or the decrease in weight gain of lambs. The aim of this work was to assess the health of the mammary gland of Santa Inês ewes at the drying and puerperium and to investigate the efficacy of a dry-off therapy with gentamicin. In this study, 64 ewes were divided in a control group (GC) and treatment group (GT), and the health of the mammary gland was assessed at the drying and puerperium. The GT ewes received 250mg of gentamicin (Gentocin® DryCow/Schering-Plough, product indicated for use in dairy cows) in each mammary half. For diagnosis, clinical examination, California Mastitis Test, somatic cell count and milk culture was performed. In the GC, of the 45 (70.3%) healthy mammary halves at the drying, 12 developed subclinical mastitis and nine clinical mastitis at the puerperium. In the GT, among 51 (79.7%) healthy mammary halves at the drying, six developed subclinical mastitis and 11 clinical mastitis at the puerperium. No association was observed between treatment and the occurrence of mastitis at puerperium. Of the 19 (29.7%) mammary halves of the GC that presented subclinical mastitis at the drying, three remained with subclinical mastitis and five developed clinical mastitis at the puerperium. In the GT, of the 13 (20.3%) mammary halves that had subclinical mastitis at the drying, four remained with subclinical mastitis and four developed clinical mastitis. No association was observed between treatment and cure or persistence of mastitis at the puerperium. The main microorganisms isolated, at the drying and puerperium, from animals with subclinical or clinical mastitis were Staphylococcus spp., predominantly coagulase negative Staphylococcus (CSN). At the puerperium, 29 cases of clinical mastitis occurred, 19 with isolation, where 10 were CNS and six S. aureus. Mannheimia haemolytica was isolated in one case of subclinical mastitis and other of clinical mastitis. News protocols and different ways of handling at drying and at puerperium must be investigated.

Technologies Used in Production Systems for Santa Inês Sheep: A Systematic Review

“…The recombinant bovine somatotropin hormone used in ewes reduced the risk of pregnancy toxemia ( 26 ). However, gentamycin (an antibiotic used for intramammary drying therapy) does not prevent new infections nor cure previous subclinical mastitis ( 27 ). Therefore, only the use of the first drug would be recommended since the antibiotic in the second situation would only increase production costs.…”

Abrupt and gradual drying-off procedure and intramammary dry treatment: Impact on udder health status of Chios breed dairy sheep

“…Moreover, intramammary dry treatment in dairy small ruminants is well documented to be one of the most effective practices for mastitis control during dry period (Bergonier and Berthelot, 2003;Contreras et al, 2007), however, in meat small ruminants the effectiveness of this preventive measure remains controversial (Pereira et al, 2018). In meat sheep and goats, dry period could be as long as 6 months (ranging from 5 to 10 months) and it is considered as a limiting factor to the use of intramammary dry treatment, since the majority of the drugs available could not remain active throughout this long dry period (Pereira et al, 2018). Additionally, spontaneous cure rates in meat small ruminants could range from 20-67% (Bergonier and Berthelot, 2003;Spanu et al, 2011), leading to an effective self-healing process, regardless the administration of intramammary dry treatment (Fox et al, 1992).…”