Mastitis pathogens in goats and sheep in the Republic of Croatia and their sensitivity to antimicrobials

A study was conducted at Kafta Humera and Tanqua Abergelle Districts from April to June, 2011 to assess the prevalence of subclinical mastitis in lactating small ruminants and identify bacterial causative agents. A total of 390 lactating animals comprising 255 goats and 135 sheep were randomly selected from population and screened for evidence of subclinical mastitis. The overall prevalence of subclinical mastitis was found to be 18.03% (46/255) and 28.14% (38/135) in goats and sheep, respectively. California mastitis test (CMT) positive milk samples were subjected to bacteriological examination and the following bacteria were isolated; coagulase negative Staphylococcus (44.7%), Staphylococcus aureus (27.7%), Escherchia coli (17.0%) and streptococci (10.63%). Risk factors; species (p = 0.021), study site (p < 0.001), sheep breed (p = 0.018) and goat breed (p = 0.009) showed statistically significant association with the occurrence of subclinical mastitis in small dairy ruminants. However, there was no statistically significant association between risk factors such as Age (p = 0.779), parity (p = 0.201) and stage of lactation (p = 0.952). Therefore, it can be concluded that mastitis is a significant disease in small ruminants that affects their productivity and measures need to be taken to control the disease.

Subclinical mastitis in small ruminants is of concern due to the animal welfare, economic, public health, productivity, and livelihood impacts that it may pose. A cross-sectional study was conducted from October 2017 to April 2018 in and around Jimma town, Southwest, Ethiopia; to estimate the prevalence of subclinical mastitis, to isolate bacterial pathogens responsible for the occurrence of subclinical mastitis, and to identify risk factors associated with the development of subclinical mastitis in small ruminants. Milk samples were collected from 186 apparently healthy lactating small ruminants, tested on the field with the California Mastitis Test, and samples tested positive were subjected to bacteriological examinations. Out of 372 milk samples collected, 92(24.8%) samples from 70 animals were positive by the California Mastitis Test and these were cultured on different media. Through bacteriological examinations, six isolates of bacteria were identified which include; S. aureus (8.1%), S. epidermidis (10.2%), S. intermidus (2.2%), S. hyicus (1.6%), S. agalactiae (3.2%), and E. coli (12.4%). The highest prevalence of subclinical mastitis recorded was due to Staphylococcus species (22%) followed by E. coli (12.4%) and the least prevalence was due to S. agalactiae (3.2%). The overall prevalence of subclinical mastitis among small ruminants was 37.6%. Age and parity number variations among small ruminants were found important in influencing the prevalence in statistically significant (P = 0.00) extents. The highest prevalence of subclinical mastitis was recorded in old (24.7%) and in small ruminants having &gt;5 parity numbers (24.7%). The high prevalence of small ruminant subclinical mastitis in the study area suggests that intervention strategies their-goal-being prevention and control of subclinical mastitis should be designed; so as to improve the welfare of animals, to save people consuming the milk of small ruminants from zoonotic risks, and to harvest the diverse benefits that may be generated from small ruminant production.

Dairy producers suffer significant economic losses due to various diseases of contagious and non-contagious etiology, among which inflammation of the mammary gland is one of the main ones. Mastitis is one of the most common diseases on dairy farms and causes significant economic losses associated with the cost of treating sick cows, reduced milk yield and quality of dairy products, and the risk of premature culling. The causative agents of mastitis are divided into two groups, among which the most important are contagious pathogens, including the five most important infectious agents: Staphylococcus aureus, Streptococcus agalactiae, Mycoplasma bovis, Streptococcus uberis, Streptococcus dysgalactiae, their habitat is sick animals and they are usually transmitted mainly from a healthy cow to a sick cow, especially through milking equipment, hands of machine milking operators, which in turn can lead to infection of the entire dairy herd. Therefore, establishing the prevalence of contagious mastitis pathogens is quite relevant today, it provides information on the possibility of creating rational and effective mastitis control programs on dairy farms, and also fills an important gap in veterinary medicine and farm management practice. The aim of this study was to identify and establish the prevalence of contagious mastitis pathogens in tank milk samples using bacteriological and molecular genetic (PCR-RFLP) studies. Molecular genetic studies were performed by real-time polymerase chain reaction (RT-PCR). Nucleic acids were isolated using the KingFisher Purification System automatic isolation system using the MagMAX™ CORE Nucleic Acid Purification Kit (Thermo Fisher Scientific, USA). For the amplification reaction of the isolated nucleic acids, commercial VetMAX MastiType Micro4 Kit (Applied Biosystems™ by Thermo Fisher Scientific, USA) was used. The reaction was performed on a real-time PCR product detection system using a QuantStudio5 Real Time PCR System (Thermo Fisher Scientific, USA). Bacteriological studies of tank samples of cow milk were carried out according to generally accepted methods, the identification of bacterial cultures obtained on blood agar was carried out by MALDI-TOF using a VITEK®MS device (BioMérieux, France). The VITEK MS KB V3.2.0 US Version database was used to analyze the mass spectra. The results of the study of contagious mastitis pathogens in tank milk samples by PCR-RF revealed that the most common are Streptococcus agalactiae 36% and Streptococcus uberis 35 %, Staphylococcus aureus occupies an intermediate position, accounting for 24 % of all isolates, Mycoplasma bovis, in turn, accounts for only 5% of isolates. When analyzing the data of the results of molecular genetic studies, it was found that the following associations of pathogens of contagious mastitis in tank milk samples were found Streptococcus uberis, Staphylococcus aureus, Streptococcus agalactiae – 29,8 %, Streptococcus agalactiae, Streptococcus uberis – 21,3 %, Streptococcus agalactiae, Staphylococcus aureus – 19,1 %, Streptococcus uberis, Staphylococcus aureus – 14,9 %, Streptococcus uberis, Staphylococcus aureus, Streptococcus agalactiae, Mycoplasma bovis and Streptococcus uberis, Mycoplasma bovis – 4,3 %, respectively. The associations of infectious agents Streptococcus uberis, Mycoplasma bovis, Streptococcus agalactiae; Mycoplasma bovis, Streptococcus agalactiae and Streptococcus uberis, Mycoplasma bovis, Staphylococcus aureus were found once each, which is 2,1 %. The bacteriological examination of tank milk samples showed that the most commonly detected contagious pathogens were Streptococcus agalactiae – 55 % and Streptococcus uberis – 28 %, Staphylococcus aureus accounted for 11 % of isolates, and Streptococcus dysgalactiae was identified in only 6 % of tank milk samples. The following associations of pathogens of contagious mastitis were most often found in tank milk samples: Streptococcus agalactiae and Staphylococcus aureus – 35,7 %, Streptococcus uberis and Staphylococcus aureus – 28,6 %, Streptococcus uberis and Streptococcus agalactiae – 21,4 %. The associations of pathogens Streptococcus uberis, Staphylococcus aureus, Streptococcus agalactiae and Streptococcus uberis, Streptococcus dysgalactiae were found in tank samples only once, which is 7,1 % each.

Clinical mastitis in small ruminants is usually seen with an incidence of less than 5% and most cases, especially with hyperacute evolution, are not referred for hospital care. During the 5-year survey, 16 goats and 7 sheep, totaling 23 small ruminants, met the inclusion criteria with a definitive diagnosis of clinical mastitis. Clinical signs ranged greatly among cases, varying from septic state in hyperacute cases, and enlarged, pendulous udder associated with chronic pain and abnormal gait in chronic cases. Microbiological culture revealed a wide array of bacterial pathogens, including Staphylococcus aureus, Escherichia coli, Streptococcus spp., and Pasteurella spp. In vitro antimicrobial susceptibility profiles varied greatly among bacteria isolates, ranging from sensitive to all tested antimicrobials to a multi-resistant profile. Pathological features included hyperemia and dark red areas of necrosis in the skin, marked hyperemia of the affected gland at the cut surface, lactiferous ducts and gland cisterns filled by cloudy or suppurative fluid, abscesses, and hardness of the mammary gland parenchyma. This retrospective study highlights the multifactorial nature and clinical variability of mastitis in small ruminants, demonstrating its significant impact on animal health, welfare, and production.

Goat and sheep farming in Brazil relies on an expressive herd, especially in the Northeast region of the country, where small ruminants constitute a relevant economic activity, with milk production being an important source of income in some dry areas of the Northeastern states. However, there are still some sanitary problems in the management of dairy goats, among which mastitis is highlighted, especially that of the subclinical type. Therefore, the aim of this study was to evaluate the use of antibiotics, exclusively or in combination with vaccines, in the control of sub-clinical mastitis in small ruminants. The study was conducted on a rural property located in Santa Maria da Boa Vista-PE. Fifty-three female Saanen dairy goats were allocated into four experimental groups. An antibiotic therapy with a commercial antimicrobial based on cloxacillin was used in group 1. Group 2 received the commercial vaccine indicated for herds with an incidence of Staphylococcus strains and the same antibiotic described for Group 1. Group 3 was evaluated for the exclusive use of vaccination, and Group 4 was the control group. A microbiological examination of the milk was carried out to confirm cases of mastitis. The percentage of udders, infected by coagulase-negative Staphylococcus spp. (CNS) before and after the antibiotic + vaccine treatment was 42.8 and 7.1%, respectively. It was observed that the cloxacillin-based antibiotic could be used alone or in combination with mastitis vaccines to control staphylococcal mastitis in small ruminants. Vaccination alone was not effective in reducing the number of mastitis cases; therefore, a cross reaction against CNS was not observed. Thus, further studies to determine the potential of vaccines to control sub-clinical mastitis in small ruminants are necessary.

Article Details: Received: 2020-10-14 | Accepted: 2020-11-27 | Available online: 2021-01-31 https://doi.org/10.15414/afz.2021.24.mi-prap.53-57 Abstract The objectives of this study were to determine the relationship of oxidative product levels, using malondialdehyde (MDA) as a marker on occurrence of mastitis and its causing pathogens in two dairy flocks of ewes situated in east and north of Slovakia. The diagnosis of mastitis was performed on the basis of clinical examination of the udder, macroscopic evaluation of milk, with the evaluation of Californian mastitis test (CMT) and bacteriological analysis of individual raw milk samples. From total 537 and 444 halves ewe’s milk samples were 16.6% and 23.2% positive to CMT, respectively. The prevalence of mastitis caused by bacterial pathogenes in the monitored herds was 14.3% to 19.1%, respectively. In all monitored sheep flocks were confirmed predominantly subclinical forms (SM) of intramammary infection (IMI). The highest of etiological agents in all monitored herds had coagulase negative staphylococci and coagulase positive staphylococci especially Staphylococcus aureus . Except for staphylococci were Streptococcus uberis and Streptococcus spp. most frequently pathogens isolated from mastitic sheep. The highest MDA level was observed from clinical cases of mastitis however, increased MDA levels were detectable from subclinical cases. Bacterial isolates from mastitc halves milk samples are different in levels of MDA. In this study, we found that milk samples infected with S. aureus were higher compared to other pathogens. In conclusion, differences in both severities of IMI and mastitis pathogens were associated with differences of MDA in infected udders. Keywords: sheep, milking, mastitis, lipid peroxidation, S. aureus , coagulase negative staphylococci References Contreras, A. et al. (2007). Mastitis in small ruminants. Small Ruminant Research, 68(1-2), 145–153. https://doi.org/10.1016/j.smallrumres.2006.09.011 Fthenakis, G. C. (1995). California mastitis test and White side test in diagnosis of subclinical mastitis of dairy ewes. Small Ruminant Research , 16(3), 271–276. https://doi.org/10.1016/0921-4488(95)00638-2 Hariharan, H. et al. (2004). Bacteriology and somatic cell counts in milk samples from ewes on a Scottish farm. Canadian Journal of Veterinary Research, 68(3), 188–192. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1142138/ Malinowski, E. et al. (2008). Etiological agents of dairy cows’ mastitis in western part of Poland. Polish Journal of Veterinary Sciences, 9(3), 191-194. https://pubmed.ncbi.nlm.nih.gov/17020014/ Mørk, T. et al. (2007). Clinical mastitis in ewes; bacteriology, epidemiology and clinical features. Acta Veterinaria Scandinavica , 49(1), 23. https://dx.doi.org/10.1186%2F1751-0147-49-23 Pyörälä, S. and Taponen, S. (2009). Coagulase-negative staphylococci - Emerging mastitis pathogens. Veterinary Microbiology , 34(2), 3–8. https://doi.org/10.1016/j.vetmic.2008.09.015 Sharma, N. (2011). Oxidative stress and antioxidant status during transition period in dairy cows. Asian-Australian Journal of Animal Science , 24(4), 479–484. https://www.ajas.info/upload/pdf/24-58.pdf Suriyasathaporn, W. (2006). Higher somatic cell counts resulted in higher malondialdehyde concentrations in raw cow´s milk. International Dairy Journal, 16(9), 1088–1091. https://doi.org/10.1016/j.idairyj.2005.11.004 Turk, R. et al. (2017). The role of oxidative stress and inflammatory response in the pathogenesis of mastitis in dairy cows. Mljekarstvo, 67(2), 91–101. https://doi.org/10.15567/mljekarstvo.2017.0201

BackgroundStaphylococcal mastitis is a common disease of small ruminants causing major economic losses. The problem is particularly significant in the rural areas of the Mediterranean region, where almost two thirds of the global sheep and a quarter of the global goat milk are produced. This study aimed to gain insight into the genotypes, antimicrobial resistance (AMR) profiles and virulence factors of Staphylococcus aureus isolated from clinical mastitis in small ruminants’ farms from different 25 dairy herds in six different provinces in Sardinia, Italy between December 2021 and May 2022.MethodsThirty- two S. aureus were phenotypically identified and confirmed by real-time PCR. Whole-genome sequencing (WGS) was conducted and the sequence data were analyzed to reveal the genetic diversity, AMR markers and virulence genes to draw a conclusion for a current situation of small ruminants’ clinical mastitis in dairy herds in the region and the potential public health risk. Furthermore, the phylogenetic relations between S. aureus strains within one farm and from various farms was analyzed.ResultsAll isolates proved to be phenotypically Methicillin-susceptible S. aureus (MSSA), and none of them harbored mecA/C genes. The antimicrobial resistance against Tetracycline and Erythromycin were 15.62% and 3.12%, respectively. The isolates were assigned to ten sequence types in addition to five different clonal complexes using multilocus sequence typing (MLST). Sequence types ST133 (46.9%) and ST700 (21.9%) were the dominant types, and the majority of isolates were assigned to either CC133 (56.25%) or CC130 (34.4%). Twelve different spa-types were identified among isolates, while six isolates were not assigned to known spa-types. The dominant spa-type was t1773 (18.75%) which is known to be associated with CC130. All Tetracycline-resistant isolates harbored tet genes. The only Erythromycin-resistant isolate carried the erm(T) gene. The leucocidin genes lukF-PV (P83)/lukM were detected in 20 isolates (62.5%), while one isolate (ST522) carried a chimeric leukocidin.ConclusionIn conclusion, this study showed a considerable genetic diversity of S. aureus isolated from sheep and goat mastitis in Sardinia, Italy, and the prominent sensitivity to most of antimicrobial agents relevant for mastitis treatment. These findings inform about the local mastitis control strategies and highlight a low immediate public health risk from antimicrobial resistance in this setting.

Aim:The present work aims to isolate and identify bacteria that cause mastitis in small ruminants and evaluates the antibacterial activity of some antibiotics, honey, essential oils, and plant extracts.Materials and Methods:A total of 289 milk samples were collected from udder secretions of sheep (n=189) and goat (n=100) from El-Fayoum, Beni-Suef, and Giza governorates. Screening subclinical mastitis (SCM) was done using California Mastitis Test (CMT); identification of the isolates was achieved using Gram’s staining, hemolytic pattern, colony morphology, and biochemical tests using Analytical Profile Index.Results:On clinical examination, the incidence of clinical mastitis (CM) was found to be 5.88% and 7% in sheep and goat, respectively. On CMT, SCM was found to be 25 (13.23%) and 11 (10%) in sheep and goat, respectively. Bacteriological examination of all milk samples found the presence of Staphylococcus aureus (SA) (31.1%), coagulase-negative staphylococci (CNS) (19.5%), Escherichia coli (EC) (8.3%), Streptococcus spp. (5.6%), Klebsiella spp. (3.77%), and Pseudomonas spp. (1.89%), while no bacteria were cultured from 81.66% of the samples. Identification of 9 isolates of CNS was achieved by using API staph test to Staphylococcus epidermidis, Staphylococcus hominis, Staphylococcus cohnii, and Staphylococcus saprophyticus. The highest bacterial resistance was found in EC (67.14%) followed by Kp (45.28%) and SA (26.57%).Conclusion:Onion and black cumin essential oils followed by Egyptian honey showed strong antibacterial effects against multidrug-resistant bacteria. Finally, our study proved that Egyptian honey, onion, and black cumin essential oils have a marked strong antibacterial effect against bacteria isolated from small ruminant mastitis, but still further extensive studies are needed to discover the therapeutic properties of these plant extracts and honey.

Received: 2018-05-07 | Accepted: 2018-05-14 | Available online: 2018-11-26 https://doi.org/10.15414/afz.2018.21.04.149-151 The physiological values of SCC in sheep's milk are still under discussion. The aim of study was to describe the frequency of distribution of ewes on the basis of their individual SCC. The ewes were divided into the five SCC groups (somatic cell count) on the basis of individual SCC (G1 = SCC &lt;200×10 3 cells.ml -1 , G2= SCC between 200-400×10 3 cells.ml -1 , G3 = SCC between 400-600×10 3 cells.ml -1 , G4= SCC between 600-1000×10 3 cells.ml -1 and G5 = SCC &gt;1000×10 3 cells.ml -1 ). Totally 771 samples were collected from 90 ewes throughout both milking periods from one experimental herd with minimum four milking records per year in 2016 and 2017. On the basis of SCS throughout lactation the most ewes were in the first two SCC groups (below 400×10 3 cells.ml -1 ) in 2016 and 2017 (78.89% and 83.33%, respectively). 13 animals (8 SD-Slovak dairy sheep, 5 LC-Lacaune) and 12 animals (4 SD, 8 LC) were in SCC groups over &gt;600×10 3 cells.ml -1 in 2016 and 2017, respectively. Our results significantly contribute to the possible consideration of physiological limits for sheep milk because of the highest percentage of ewes was with less than 400×10 3 cells.ml -1 .  Keywords:  ewe, milk, somatic cell counts References Arias, R., Oliete, B., Ramón, M., Arias, C., Gallego, R., Montoro, V., Pérez-Guzmán, M. D. (2012) Long-term study of environmental effects on test-day somatic cell count and milk yield in Manchega sheep. Small Ruminant Research, 106 (2), 92-97. DOI: http://dx.doi.org/10.1016/j.smallrumres.2012.03.019 Bergonier, D., De Crémoux, R., Rupp, R., Lagriffoul, G., Berthelot, X. (2003) Mastitis of dairy small ruminants. Veterinary Research , 34 (5), 689-716. DOI: https://dx.doi.org/10.1051/vetres:2003030 Contreras, A., Sierra, D., Sánchez, Z. A., Corrales, J. C., Marco, J.C., Paape, M. J., Gonzalo, C. (2007)Mastitis in small ruminants. Small Ruminant Research , 68 (1-2), 145-153.  DOI: https://dx.doi.org/10.1016/j.smallrumres.2006.09.011 Idriss, S. E., Tančin, V., Margetín, M., Tančinová, D., Sláma, P., Havlíček, Z. (2015) Frequency of distribution of somatic cell count in dairy ewe's milk. Journal of Microbiology, Biotechnology and Food Sciences, 4 (3), 148-151. DOI: https://dx.doi.org/10.15414/jmbfs.2015.4.special3.148-151 Leitner, G., Chaffer, M., Zamir, S., Mor, T., Glickman, A., Winkler, M., Weisblit, L., Saran, A. (2001) Udder disease etiology, milk somatic cell counts and NAGase activity in Israeli Assaf sheep throughout lactation. Small Ruminant Research , 39 (2), 107-112. DOI: https://dx.doi.org/10.1016/S0921-4488(00)00190-5 Leitner, G., Silanikove, N., Merin, U.(2008) Estimate of milk and curd yield loss of sheep and goats with intrammamary infection and its relation to somatic cell count. Small Ruminant Research, 74 (3), 221-225. DOI: http://dx.doi.org/10.1016/j.smallrumres.2007.02.009 Olechnowicz, J., Jaskowski, J. M. (2014) Mastitis in small ruminants. Medycyna Weterynaryjna/ Veterinary Medicine - Science And Practice, 70 (2), 67-72. Paape, M. J., Wiggans, G. R., Bannerman, D. D., Thomas, D. L., Sanders, A. H., Contreras, A., Moroni, P., Miller, R. H. (2007) Monitoring goat and sheep milk somatic cell counts. Small Ruminant Research , 68 (1-2), 114-125.DOI: https://dx.doi.org/10.1016/j.smallrumres.2006.09.014 Pengov, A. (2001)The Role of Coagulase- Negative Staphylococcus spp. and Associated Somatic Cell Counts in the Ovine Mammary Gland. Journal of Dairy Science, 84(3), 572-574. DOI: https://dx.doi.org/10.3168/jds.S0022-0302(01)74509-2 Riggio, V., Portolano, B. (2015) Genetic selection for reduced somatic cell counts in sheep milk: A review. Small Ruminant Research , 126 (10), 33-42. DOI: https://dx.doi.org/10.1016/j.smallrumres.2015.01.020 Souza, F. N., Blagitz, M. G., Penna, C. F. A. M., Della Libera, A.M. M. P., Heinemann, M. B., Cerqueira, M.M.O.P. (2012)Somaticcellcount in smallruminants: Friend or foe?Small Ruminant Research , 107 (2-3), 65-75. DOI: https://dx.doi.org/10.1016/j.smallrumres.2012.04.005 Tančin, V., Baranovič, Š., Uhrinčať, M., Mačuhová, L., Vršková, M., Oravcová, M. (2017a) Somatic cell count in raw ewes milk in dairy practice: frequency of distribution and possible effect on milk yield and composition. Mljekarstvo , 67 (4), 253-260. Tančin, V., Uhrinčať, M., Mačuhová, L., Baranovič, Š., Vršková, M.(2017b) Somatic cell count in milk of individual Lacaune ewes under practical conditions in Slovakia: Possible effect on milk yield and its composition. Potravinarstvo – Slovak Journal of Food Sciences, 11 (1), 386-390. DOI: https://dx.doi.org/10.5219/767 Vršková, V., Tančin, V., Kirchnerová, K., Sláma, P. (2015) Evaluation of daily milk production in Tsigai ewes by somatic cell count. Potravinarstvo – Slovak Journal of Food Sciences, 9 (1), 206-210. DOI : https://dx.doi.org/10.5219/439

This study was conducted to determine the prevalence of coliform bacteria and fungi in ovine and caprine raw milk in Plateau State of Nigeria. In a cross sectional study, a total of 412 milk samples were collected aseptically and 206 questionnaires form where data such as breed, age, parity, lactation stage, floor type, and husbandry system were analyzed. Ewes and does without clinical mastitis were subjected to California Mastitis Test (CMT) to determine the presence of subclinical mastitis. Bacteriological assays and antibiotic susceptibility tests were performed according to standard guidelines. Fungal assays and identification were done according to standard protocol. The overall prevalence of subclinical mastitis for ewes and does were 28.2 and 35.8% respectively. Out of the risk factors examined, age and floor type showed statistically significant relationship with mastitis. Coliforms isolated from milk samples included Escherichia coli, Klebsiella pneumoniae, Citrobacter freundii, Enterobacter aerogenes, and Serratia marcescens. The highest coliform isolated among the ewes with 38% prevalence was E. coli and the least was S. marcescens with 2.5%. Among the does, E coli had the highest prevalence as well with 43.1% and E. aerogenes the least with 1.5%. Aspergillus species had 49 isolates out of the 94 fungal isolates (52.1%) of mycotic agents of mastitis in small ruminants. Most antibiotics used in this study showed extremely high level of antimicrobial resistance especially for Amoxicillin-clavulanic acid 45/79 (57.0%) and 53/65 (81.5%) in coliforms isolated from ewes and does respectively. The principle of one health approach which targets the environment, animals and humans should be considered important. Sensitization of pastoralists on good hygienic measures, and treatment of animals by qualified and registered veterinary personnel should be intensified.

Este artigo objetivou revisar as informações recentes sobre mastite em pequenos ruminantes, abrangendo etiologia, epidemiologia, aspectos de controle e profilaxia. Houve a preocupação em reunir resultados de estudos desenvolvidos no Brasil, uma vez que a mastite tem a interferência de uma série de fatores, como fatores ambientais e outros decorrentes dos sistemas de manejo empregados, condições essas determinantes para etiologia e epidemiologia da enfermidade. A prevalência da mastite em caprinos varia entre 22 e 75%, sendo que os casos de mastite subclínica são os mais frequentes. Existe uma carência de trabalhos voltados para os aspectos epidemiológicos da enfermidade no nosso país. Contudo, observa-se que a mastite vem assumindo importância cada vez maior nos rebanhos voltados para produção de carne, sendo encontrados resultados de pesquisa, principalmente na espécie ovina. A mastite estafilocócica corresponde à maior fração nas infecções intramamárias em pequenos ruminantes. O caráter zoonótico de alguns patógenos, a exemplo do Staphylococcus aureus ressalta a importância da implantação de programas de controle em propriedades leiteiras. Algumas das ferramentas de diagnóstico ainda necessitam de padronização, principalmente para espécie caprina que apresenta uma série de particularidades. Ainda são discutidas as principais estratégias de controle como o manejo de fêmeas e suas crias, os procedimentos de ordenha e a utilização de vacinas.

The current study was carried out on a number of sheep and goats farms during the period extended from January 2016 till the end of December 2017 in order to estimate the prevalence of subclinical mastitis in small ruminants and highlight the role of Staphylococcus species in inducing such infection. For this aim, about 940 milk samples collected from sheep and goats' farms (455 samples/ sheep and 485 samples/ goats) were subjected to California Mastitis test (CMT) to detect the prevalence of subclinical mastitis, then positive CMT samples in addition to; 100 bedding samples (50 samples / each species) collected from different sites of animal's yards particularly from wetted areas with high moisture and organic matter load and 100 water samples collected from different sites of animal's yards (50 samples / each species) were subjected to the ordinary bacterial culturing steps for isolation and identification of Staphylococcus species. The results revealed prevalence of subclinical mastitis estimated by 32.96% and 30.92% in sheep and Goat farms, respectively. The total prevalence of Staphylococci in Sheep farms was 27.2% where S. aureus accounted for 12.4% and Coagulase Negative Staphylococci (CNS) represented the highest percentage (14.8%). The highest isolation rate recorded in bedding samples (34.0%) followed by milk samples (26.0%) and water samples (24.0%), while in goats farms the prevalence of Staphylococci species was 32.0% (16.8% S. aureus and 15.2% CNS) with highest rate of isolation from bedding samples (36.0%) followed by milk samples (34.0%) then water samples (22.0%). In addition, the isolated Staphylococcus strains where tested for their sensitivity to certain commercial antibiotics using disc diffusion method. The results revealed complete resistant of isolated S. aureus to Enrofloxacin (5 µg) and Oxytetracycline (30 µg) and moderate sensitivity to Amoxicillin (10 µg) and Erythromycin (15 µg). While CNS showed complete resistant to Flumequine (30 µg), Doxycycline (30 µg) and Sulpha.-Trimethoprim (25 µg), in contrary, they were highly sensitive to Amoxicillin (10 µg) and Erythromycin (15 µg) antibiotics. At last, molecular detection of clfA gene specific for coagulase positive Staphylococci were performed.

Mastitis in small ruminants.

Milk electrical conductivity and mastitis status in dairy goats: Results from a pilot study

Bacterial mastitis in small ruminants is a complex disease, with massive economic loss in dairy sheep/goat industry due to poor productivity. The current mastitis prevention strategy relies on culling of infected ewes or does and or the use of antimicrobial agents to eliminate the bacterial infection. This has a potential risk for developing antibiotic resistant bacteria, posing human health risk from consumption of raw sheep or goat dairy products. Existing experimental and licensed vaccines on the market are ineffective against reducing the risk of mastitis in herds or flocks. Raising the needs for development of improved vaccines against mastitis for use in sheep and goats. This review examines, current understanding of the pathological processes and immunological responses against bacterial mastitis, using S. aureus as an example. By highlighting the protective defense mechanism induced in the udder against S. aureus mastitis. Based on evidence from published studies on pathological process and protective immune response mechanism, the need for improved vaccines for prevention of mastitis in small ruminant is highlighted and the development of a vaccine capable of enhancing immune response mechanism, that reduce the establishment of intramammary infection through induction of local IgA, IgG2 and Th17 immune responses is proposed.