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In this study, 73 non-pregnant and clinically healthy and lactating Holstein cows without any clinical signs, and with a mean parity of 3.2 ± 1.4, days in milk at the beginning of study 110 ± 20 days, body condition scour (BCS) of about 3.2 ± 0.3, and milk production rate of 48± 10 kg were selected and randomly placed in two treatment and control groups. In the treatment group (n=36), arginine (155 µmol / kg body weight) was injected once every 8 hours a day for 6 days, and in the control group (n=37) saline solution (0.11 ml/kg body weight, once every 8 hours a day) was injected for 6 days. The results showed that there was no difference between the treatment and the controle group in terms of milk production (38.5 and 36 kg, P=0.3), fat (3.7 and 3.8%, P=0.8) and protein (3.1 and 3.1%, P=0.5) levels. It was concluded from this study that the use of arginine after the peak of milk production could not increase the fat, protein, and production levels of milk. [ABSTRACT FROM AUTHOR]

The aim of the present study was to evaluate the efficacy of macrolides to eliminate intramammary infection (IMI) caused by Staphylococcus aureus (S. aureus) and Streptoccus spp. 3 weeks before calving time. Eighty Holstein dairy cows with subclinical mastitis pathogens were divided into three groups. Three weeks before expected parturition time, cows in group 1 received tilmicosin (n = 29), cows in group 2 received tylosin (n = 30) and cows in group 3 were left as negative control (n = 21). Milk samples were obtained on 3 and 7 days after calving. Randomly amplified polymorphic DNA (RAPD) method was determined for all of the S. aureus isolates that had the same isolates before and after parturition. The total cure rate was 63.33, 75.86 and 66.66% for tylosin, tilmicosin and control groups, respectively. Furthermore, cure rates were not significant, when each type of mastitis causing pathogens were considered separately. The incidence of clinical mastitis during 60 days after calving for tylosin, tilmicosin and Control groups was 23.33, 27.58 and 38.09%, respectively. Only four S. aureus isolated before drying-off were similar to post-calving isolate, according to RAPD-PCR method. In conclusion, antibiotic therapy before calving improved the cure rate numerically, however, it was not significant. [ABSTRACT FROM AUTHOR]

Problem statement: Little research has focused on treatment of cows with subclinical mastitis during lactation. The seed of Nigella sativa Linn. (Ranunculaceae), commonly known as black seed or black cumin, is used in folk (herbal) medicine. Approach: Objectives of this study were to evaluate the effect of Nigella sativa Extract (NSE) with two regimens for treatment of subclinical mastitis in lactating dairy cows and to determine which regimen enhanced efficacy of it. Results: From one hundred Holstein dairy research herd in Mashhad-Iran, 83 cows with a total of 157 subclinically Staphylococcus aureus infected quarters were included. Cows were enrolled in the study based on milk somatic cell counts >200,000 [mL.sup.-1] and isolation of Staphylococcus aureus in 3 samples obtained 1 week apart. About 10 cc of NSE (in paraffin: 200 mg [cc.sup.-1]) was administered via intramammary infusion. First, Cows were divided into three treatment groups. Group 1 (37 cows) received intramammary infusion at each milking (3 times daily) for 3 days with 10 cc NSE. Group 2 (24 cows) received the same intramammary infusion but only once daily for 3 days. The third, 22 cows were included as an untreated negative control group. Results in bacteriologic cure of 69.4% of quarters and 59.5% of cows (Group 1) compared to 60% of quarters and 45.8% of cows (Group 2). Test for mastitis diagnosis Somatic cell counts of milk from quarters that were not cured were higher prior to initiation of treatment than those cured. A bacteriological cure was defined as a treated infected mammary quarter that was bacteriologically negative for the presence of S. aureus at 3-7 day after the last treatment. Conclusion: All two Nigella sativa treatment regimens were significantly better than the negative control and the nine dose Nigella sativa treatment regimen treatment group was not significantly better than the three dose treatment group (p = 0.332). Key words: Subclinical mastitis, Staphylococcus aureus, Nigella sativa, INTRODUCTION Clinical and subclinical mastitis are the 2 major forms of the diseases. Clinical mastitis results in alterations in milk composition and appearance, decreased milk production, elevated body temperature and [...]

The present study aimed to evaluate the efficacy of different hormonal interventions in the treatment of cystic ovarian follicles (COF) based on different scenarios, including the size of the cyst and the presence of other follicles on the ovaries of dairy cows. A total of 199 Holstein cows with COF in the first 100 days postpartum were enrolled in the study. These cows were randomly assigned to the four following groups: 1) GnRH (G) group: intramuscular (IM) injections of 100 µg gonadorelin acetate on day 0 and 150 µg d-cloprostenol 7-12 days later, 2) double GnRH (DG) group: two IM injections of 100 µg gonadorelin acetate at 6 h intervals on day 0 and d-cloprostenol 7-12 days later, 3) intravaginal progesterone device (IPD) group: insertion of PRID Delta for 7-12 days and injection of d-cloprostenol on the withdrawal of PRID Delta, and 4) control group: IM injection of 2 mL sterile saline on day 0 and 7-12 days later. The cure rate of COF significantly improved in the G and DG groups, in comparison with the IPD and control groups. ! ere was no significant difference between the cows in the G and DG groups. In the control group, animals with ovarian cysts smaller than 2.5 cm had a significantly greater self-cure rate, compared to the other cows. In conclusion, this field study demonstrated a good clinical cure in the groups of cows treated by GnRH. However, no improvement was observed in the reproductive performance of these animals. [ABSTRACT FROM AUTHOR]

The present study aimed to determine the effect of administrating prostaglandin F2α (PGF2α) and GnRH at the time of artificial insemination (AI) on the pregnancy per artificial insemination (P/AI) and the pregnancy survival rate of dairy cows. A number of 830 lactating Holstein cows were randomly divided into four groups. Cows in group 1 (n=200) treated with 150 µg d-cloprostenol. In group 2 (n=212), cows received 10 µg buserelin acetate, and group 3 (n=205) was treated with both 150 µg d-cloprostenol and 10 µg buserelin acetate. In addition, 213 cows were assigned as control group which received normal saline as placebo (group 4). To measure progesterone, milk samples were collected at the insemination day and five days later. Pregnancy diagnosis was performed 28 and 60 days after the insemination, and the size and number of corpus luteum (CL) and twin pregnancies were recorded. Hormone therapies had no effect on the P/AI, pregnancy survival rate, and the size and number of CL. The P/AI ratio in groups 1, 2, 3 and 4 were 38.50%, 42.92%, 41.46% and 40.84%, and the pregnancy survival rates in groups 1, 2, 3 and 4 were 84.42%, 86.81%, 88.23% and 83.91%, respectively. The probability of a twin pregnancy was significantly higher in group 1 (15.58%) than other groups. There was no significant difference between groups in terms of the offspring gender. In conclusion, the administration of d-cloprostenol or buserelin acetate at the time of AI had no effect on P/AI and pregnancy survival rate in dairy cattle under no heat stress condition, while the administration of d-cloprostenol increased the probability of twin pregnancies. [ABSTRACT FROM AUTHOR]