Fatores de risco para mastite infecciosa em cabras leiteiras criadas no Estado da Bahia

Influence of natural and climatic conditions on the distribution and forms of contagious agalactia in sheep in Bessarabia, Ukraine

Introduction

Contagious agalactia of ruminants is an endemic disease caused by Mycoplasma agalactiae in flicting significant losses on farms in deaths and forced slaughter of sick animals, abortions, births of sick young animals, and reduced milk and wool production. The aim of the study was to determine the influence of hydrometeorological conditions on the distribution and forms of contagious agalactia in sheep in Bessarabia, Ukraine.

Material and Methods

The epizootic situation regarding contagious agalactia was studied during 2011–2021 on sheep farms in the south of the Odesa region in Bessarabia. Over two million blood samples from sheep aged 1–6 years were serologically investigated and the prevalence of agalactia was correlated with Selyaninov’s hydrothermal coefficient for each sampling year.

Results

High rates of infection of sheep with contagious agalactia (from 13.1% to 14.4%) were registered in 2012, 2016 and 2021, years which according to the hydrothermal coefficient of 1.0 were sufficiently moist. The lowest incidence rates, from 6.5% to 7.4%, were registered in the very dry 2013, 2014 and 2019 with hydrothermal coefficients of 0.5‒0.6. In sufficiently moist years, contagious agalactia of sheep manifested itself in the mastitic form, while in the dry period the mastitic form was half as prevalent, and the mixed, articular and ocular forms of the disease proliferated.

Conclusion

The results indicate the circulation of Mycoplasma agalactiae among small ruminants in Bessarabia, and that the prevalence and the course of the associated disease depend on the humidity of the climate, i.e. the value of the hydrothermal coefficient.

Multiresistant zoonotic pathogens isolated from goat milk in Northeastern Brazil

Dairy goats play a significant role in socio-economic, cultural, and nutritional development in many countries. This study aimed to identify multiresistant zoonotic pathogens causing mastitis in goats, in addition to characterizing them for the presence of resistance genes and phenotypic resistance. A total of 714 milk samples from 357 lactating goats in 12 farms in the Northeast region of Brazil were analyzed. The isolates were submitted to Matrix Associated Laser Desorption-Ionization - Time of Flight to identify bacterial species, Polymerase Chain Reaction (PCR) to search for resistance genes, and an antibiogram to evaluate the phenotypic profile of antimicrobial resistance. A total of 214 pathogens were identified and bacterial prevalence was 83.29 % (178/214) Staphylococcus spp.; 6.50 % (14/214) Micrococcus luteus; 3.73 % (8/214) Corynebacterium spp.; 2.80 % (6/214) Bacillus spp.; 1.38 % (3/214) Escherichia coli; 0.92 % (2/214) Enterobacter cloacae; 0.46 % (1/214) Aerococcus viridans; 0.46 % (1/214) Morganella morganii; and 0.46 % (1/214) Turicella otitidis. As for gene frequency, 64.60 % (115/178) of the isolates carried the blaZ gene; 37.07 % (66/178) norA; 22.47 % (40/178) tet(L); 16.85 % (30/178) tet(M); 14.04 % (25/178) norB; 8.42 % (15/178) vanA; 7.30 % (13/178) msrA; 6.41 % (5/178) tet-38; 4.49 % (8/178) norC; 2.25 % (4/178) mecA; and 0.56 % (1/178) vanB. Emerging multiresistant zoonotic pathogens are present in the goat milk production chain, especially the coagulase-negative Staphylococcus species that pose a risk to human and animal health.

Age and Seasonal Pattern of Contagious Agalactia in Small Ruminants in Ukraine

Introduction

The aim of the study was to determine how the spread of contagious agalactia in sheep and goats in the Odesa region depended on the age of the animals and the season.

Material and Methods

From January 2016 to December 2018, 1,964 ewes and 1,484 nanny goats of different age groups were studied by ELISA for antibodies to Mycoplasma agalactiae.

Results

The highest incidence of contagious agalactia was registered in one-year-old animals and was 59.7‒83.0%, two-year-old ruminants showed 17.0‒40.3% prevalence, in livestock at the age of 3–4 years no serological evidence of the disease was registered and in ewes and nanny goats older than 5–6 years 1.5–3.6% were infected. The most susceptible were young animals at the age of one-month (11.6‒14.5%). The first peak of the disease was recorded in March‒April (21.0‒26.1%), in the lambing period, which coincided with the beginning of lactation and the suckling period, and the second peak occurred in June–July (28.9‒34.2%), the period of maximum lactation and of manual milking of sheep and goats.

Conclusion

The results of serological investigations indicate the circulation of M. agalactiae in small ruminants in the south of Ukraine. To avoid greater dissemination of the pathogen, appropriate measures should be applied and strategies for its control need to be drawn up.

MINIMUM BACTERICIDAL CONCENTRATION OF COMMERCIAL DISINFECTANTS ON STAPHYLOCOCCUS SPP. ISOLATED FROM MASTITIS IN GOATS AND DETECTION OF THE icaD GENE

Abstract This study aimed to evaluate the in vitro efficacy of commercial disinfectants on Staphylococcus spp., isolated from mastitis cases in goats, and to associate the observed resistance with the presence of the icaD gene. Broth microdilution was employed to evaluate the in vitro antimicrobial activity of the disinfectants, whereas the Congo Red technique was used for the evaluation of biofilm production and amplification of the icaD gene. All evaluated samples were sensitive to disinfectants, with the following ranges of activity: quaternary ammonium (0.13 - 21.33 µg/ml), chlorhexidine (4.00 - 313.00 µg/ml) and iodine (190.00 - 12500.00 µg/ml); however, the sodium hypochlorite-based disinfectant showed no bactericidal activity in the concentration range from 15.0 to 0.03 µg/ml. The icaD gene presented a frequency of 14.7% in the isolate samples. Fisher’s exact test showed a significant effect of the relation between the minimum bactericidal concentration value of the quaternary ammonium-based disinfectant and the presence/absence of the icaD gene (P <0.01). Commercial disinfectants with quaternary ammonium, chlorhexidine and iodine active ingredients presented in vitro activity even at concentrations lower than those recommended by the manufacturers. Therefore, the periodic evaluation of the sensitivity profile of the disinfectants must be performed.