Epidemiological and Clinical Study of Clinical Mastitis in Awassi Ewes at Jedrin Station, Syria 

Abd Al-Naser Al-Omar*(1) Mohamad Rokbi(2) Sameer Al-Shareey(1) Abd Al-Fattah Hamada(3)

(1). Agricultural Research Center in Hama, General Commission for Scientific and Agricultural Research (GCSAR), Hama, Syria.
(2). Agricultural Research Center in Aleppo, GCSAR, Aleppo, Syria.
(3). Avico company for medical manufacturer, Hama, Syria.

(*Corresponding author: Dr. Abd Al-Naser Al-Omar, Agricultural Research Center in Hama, GCSAR, Hama, Syria. E-mail: abdnaser64@gmail.com).

Received: 17/02/ 2015                                     Accepted: 23/04/ 2015 


This research was conducted to determine bacterial etiology, epidemiological and clinical features of clinical mastitis cases in Syrian, using Awassi ewes aged 2-6 years, which is hold for both milk and meat production. The research was done during the last twenty years (from 1993 to 2012) at Jedrine Research Station, General Commission for Scientific Agricultural Research (GCSAR), Hama, Syria. 75 milk samples was collected from clinical infected ewes in different times, and subjected to the bacteriological analysis and sensitive reactions. The percentage of clinical mastitis was 6.05% (261 out of 4247). There were a significant difference (p≤0.01) in terms of the percentage of infection by the three types of mastitis, the percentages were as follow: Acute (76.6%), gangrenous (18.8%), and chronic (4.6%). The percentage of the mastitis that was most often registered in one half was (73.94%), while in two halves the percentage was (26.05%). Most of the mastitis occurred during first two months after lambing (74%), the rest (26%) was after weaning of lambs. Chi-square test showed significant differences (p≤0.01) in the frequency of mastitis cases within different months after parturition, and in lactation seasons. In terms of frequency of mastitis cases the highest frequency was in the third production season (27.97%), where the ewes suffered more from clinical mastitis (p≤0.01), then the second production season (26.05%), and the lowest was the first production season (10.72%). Using hypothesis test to estimate the difference between two groups, Z value (Z=0.47) was within the normal range (±1.96), so there was no significant difference in the occurrence of mastitis between manual stripping and machine lactation. The results of bacterial analysis for 75 milk samples showed a bacterial growth in 62 samples (82.66%). The most prevalent isolated bacteria were staphylococcus aureus (32.85%), Pasteurella hymolytica(18.57%), E.coli(14.3%),
Klebsiella (11.4%), Actinomyces pyoges (10%), Stretococcus lactis (7.14%), and Bacillus subtilis (5.71%). The percentage of the ewes that recovered after the treatment by different antibiotics was 71.26%. Enroflouxacine showed high effectiveness for most isolated bacterial strains, followed by Gentamicin ,  then Norfloxacin, Oxytetracycline , Ampicillin, Sulfa compounds, and lastly Neomycin. Most bacterial strains were resistant to Penicillin and Erythromycine. The Staphylococcus aureus was more sensitive to antibiotics, while the Actinobacillus pyogenes was more resistant, this ensure the necessity of the intensification of sanitary control for protection and prevention of mastitis especially during first two months after lambing, and in multi-partied ewes, and the treatment of the infected ewes with efficient antibiotics according to sensitivity tests, in addition to the improvement of environmental conditions in breeding stations for Awassi ewes.

Key words: Prevalence, Clinical mastitis, Awassi ewes, Syria.

Full paper in Arabic:دراسة وبائية وسريرية لحالات التهاب الضرع لأغنام العواس في محطة جدرين، سورية