Effects of intramammary infusion of cloxacillin on profiles of serum biochemical parameters in dry and lactating dairy goats

Two experiments were conducted to investigate the effects of cloxacillin administration, a semi-synthetic antibiotic resistant to penicillinase, on changes in serum biochemical indices of dry and lactating dairy goats. In Experiment 1, 18 healthy dry French-Alpine does, 3 to 5 years old, weighing 52-62 kg, were randomly assigned to a control(six) or antibiotic treated (12) group. In Experiment 2, nine healthy lactating French-Alpine does with the same body conditions were randomly assigned to the control (four) and the treated (five) groups. For drug treatments, dry goats received an intramammary infusion of 1000 mg cloxacillin benzathine via a single dose of 500 mg to each teat, and milking goats received 1200 mg sodium cloxacillin via three dosages of 200 mg to each teat. Blood samples were taken by jugular venipuncture at 0.0, 0.5, 1.0, 1.5, 2.0, 2.5, 3, 7, 10, and 14 days post-treatment. Results showed that two main effects (drug treatment and sampling period) for dry goats were significant (P < 0.01) for all tested parameters except for inorganic phosphorus (P). Main effects for lactating goats were significant only for total protein (PRO), albumin (ALE), blood urea nitrogen (BUN), glutamic pyruvic transaminase (SGPT), and lactate dehydrogenase (LDH). Cloxacillin administration had a greater influence on serum chemical parameters in,dry goats than in milking goats. Levels of ALE, creatine (CRT) and gamma-glutamyltransferase (SGGT) in dry goats were greatest at 2.5 day post-infusion, while those of PRO, ALE, P and glutamic-oxaloacetic transaminase (SGOT) in lactating goats were highest at 6 h post-treatment. Correlation coefficients (r) between levels of tested parameters and serum PRO were significant (P < 0.05 or 0.01) except for SGPT and creatinine phosphokinase (CPK) in dry treated goats, whereas blood glucose displayed poor correlation with most parameters, especially in controls of both dry and lactating goats. The dosage levels of cloxacillin used in this study showed no detrimental effects on healthy dry and milking goats. The drug may be applicable to dairy goat production. (C) 1997 Elsevier Science B.V.