Further studies on the prevalence of subclinical mastitis in dairy cows in el-Gharbia and Kafr el-Sheikh Governorates with special observation to antibiotic sensitivity

الملخص EN

A total of 1136-quarter cow’s milk samples were collected from apparently healthy cow’s from 2 dairy farms in El Gharbia and 3 dairy farms in Kafr El- Sheikh Governorates (Egypt).

All samples were screened for subclinicl mastitis using California Mastitis Test (CMT), Somatic Cell Count (SCC), lactose and chloride content.

All Positive CMT samples were examined microbiologically for isolating the most causative microbial agents of subclinical mastitis.

136 (22.5%) samples collected from El-Gharbia Governorate were positive for CMT .Of them 100 samples (73.5%) scored 2+ and 36 (26.5%) scored 3+; 120 (20%) contained lactose below 4.7% and 140 (23.2%) had chloride content greater than 0.14%.

While 65 (12.2%) quarter milk samples collected from Kafr El-Sheikh farms were CMT positive, of them 24 (36.9%) samples scored 2+ and 41(63.1%) samples scored 3+ ; 72 (13.5%) samples contained lactose less than 4.7% and 119 (22.4%) had chloride content greater than 0.14% .

Infectious organisms isolated from CMT positive samples were Coliforms (88.2%), Staphylococci (26.5%) and E-coli (14.7%) while both coagulase +ve Staph.

aureus and Strept.

agalactiae failed to be detected from El- Gharbia quarter samples.

On the other hand Coliforms , Staphylococci, coagulase +v Staph.

aureus , E-coli and Strept agalactiae were isolated with a percentages ranging from 1.5 to 52.3 % from Kafr El-Sheikh samples.

Somatic cell count (SCC) ranged from >105 to <107in CMT positive samples.

The in vitro sensitivity pattern of the isolated organisms against 7 antibiotics was tested.

Flumequin and Gentamycin gave the best results in inhibiting all the tested Staph.

aureus , E-coli and Strept.

agalactiae tested strains.

It is concluded that subclinical mastitis in dairy cows is a serious problem in the surveyed area.