Clinical Effects Of Cefquinome On Dairy Cow Mastitis And Its Residue In The Milk

Dairy cows mastitis is one of the most common disease in cow industry. People have focused on prevention and treatment of the cow mastitis. Therefore, it is particularly important to choose a kind of high efficient, safe, low residue of new antibiotic to treat cow mastitis, reduce the economic loss, ensure the high quality of milk, and protect human health.51 milk samples of clinical dairy cow mastitis were collected from a dairy cow farm of Tangshan region, the isolation and biochemical identification of pathogenic bacteria, and drug susceptibility test were made. The results showed that 8 species of 159 bacteria were isolated from 51 samples, including 49 Staphylococcus aureus (30.8%), 21Escherichia Coli (13.2%), 11 Staphylococcus epidermidis (6.9%), 9 Staphylococcus saprophyticus (5.7%), 37 Streptococcus mastitidis (23.3%), 26 Streptococcus dysgalactiae(16.4%),2 Klebsiella (1.3%), 4 Bacillus termo (2.4%). Staphylococcus aureus, Escherichia coli, Streptococcus mastitidis and Streptococcus dysgalactiae were the main bacteria of cow clinical mastitis. The main pathogens were 83.6% of the total bacteria (133/159). The drug susceptibility test showed that the most sensitive antibiotics to pathogenic bacteria were middle and high dose of Cefquinome sulfate, Gentamicin, Enrofloxacin, Amikacin and tobramycin.Lactation rabbits were selected to induce mastitis model with 104CFU, 106CFU and 108CFU suspension of Staphylococcus aureus. The results showed that 106CFU Staphylococcus aureus was the optimal concentration to make mastitis model. Different doses of Cefquinome ointment were administered into milk pool and its suspension was injected into muscle of the rabbit models. The Clinical treatment effects were observed, and the routine blood test was done to ascertain the best dose. The results showed that the total number of leukocytes, neutrophilic, lymphocyte and percentage of neutrophilic decreased significantly with middle and high doses (P<0.01), percentage of lymphocyte were increased significantly and there was no significant difference when compared with healthy control. The red, swollen, pain reaction of udder disappeared, lactation returned to normal, the cure rate was 100%(3/3), so the best treatment dose of Cefquinome suspension was 0.5mg/pool and Cefquinome ointment was 1mg/kg.Clinical mastitis dairy cows were treated with different dose of Cefquinome Sulphate from a dairy cow farm of Tangshan region. Serum and whey were separated to determine the biochemical indices from the blood and milk before and after treatment, and detect the rate of positive turning negativity through bacterial culture, identification and counting before and after treatment, then judge the therapeutic effect through clinical curative effect, various biochemical indicators and etiology. The activity of SOD and GSH-PX radical scavenging enzyme increased significantly by suspension with ointment (Ⅲ, P<0.01), the content of NO, MDA free radicals and LF decreased significantly(P<0.01), there was no significant difference with healthy control, the number and type of the pathogen reduced after treatment, the best effect wasⅢgroup. Total cure rate reached to 70%, the total effective was 96.7%, the positive turning negativity rate was 77.8%, it reached to basic therapeutic purposes for clinical mastitis. It is suggested that the suspension combined with ointment was optimal for clinical dairy cow mastitis.0.5, 12, 24, 36, 48, 54, 66, 72, 84 and 96h after the last medication, the milk samples in the treatment groups were collected, the drug residue was detected by ECLIPSE 50 kit. The results showed that, after drug discontinuation, the milk samples with 48h of ointment treatment appeared green or yellow, showed negative. The milk samples with 84h of suspension agent treatment appeared green or yellow, showed negative. The milk samples with 66h of suspension combined with ointment treatment appeared green or yellow, showed negative. This showed the content of Cefquinome in the milk was less than the detection limit of 0.015μg/mL after 84h, which was lower than the designed maximum residue of the European Union.