​Studies on Cefquinome Sulfate Intramammary Infusion Composited with Varied Excipients for the Prevention of Dairy Cows Mastitis in the Dry Cow Period

Background: The prevention and treatment of dairy cow mastitis during the dry period are crucial for the dairy industry. In this work, 200 dairy cows without mastitis and normal entering dry period were selected and randomly divided into 4 groups, for the first time, to explore the prevention effects using the different formulations of Cefquinome Sulfate Breast Injection with varied excipients. Methods: Three formulations with various excipients were further evaluated based on the drug residue analysis, somatic cell reduction in the milk and clinical symptoms of mastitis. In the control group, cloxacillin benzathine was utilized for comparisons. Result: All three Cefquinome test groups showed a better effect on prevention than the benzathine cloxacillin group in terms of drug release time, post-partum drug residue, reducing somatic cell count and preventing mastitis in the dry period. Various excipients showed slightly different impacts on the drug residues, the changes in somatic cell counts of dairy cows before and after medication. The prevention effects on mastitis from different excipients were similar after 30 d.

Determination of antibacterial residues in raw cattle beef in some selective areas of Mymensingh District during Eid-ul-Adha

Background: Antibiotic residue in foods of animal origin is a growing public health concern in recent time. Indiscriminate use of antibacterials in food animal production and ignoring proper withdrawal period may lead to drug residue in milk, beef and eggs. The present study was conducted to detect antibacterial residues in raw cattle beef samples. Methods: One hundred cattle beef samples were collected from four Upazillas of Mymensingh named Gofargaon, Fulpur, Dhobaura and Bhaluka, Bangladesh during the period of Eid-ul-adha in 2018. The residue of two most commonly used antibacterials named oxytetracycline (OTC) and sulphadimidin (SDI) were quantified by using High Performance Liquid Chromatography (HPLC). Results The mean concentration of OTC and SDI residues in raw beef samples were 0.145 µg/ml and 0.094 µg/ml and the concentration ranged from 0.104-0.435 µg/ml and 0.083-0.357 µg/ml, respectively. About 59% and 43% beef samples contained some levels of OTC and SDI residue, respectively. Importantly, 19% and 12% beef samples exceeded maximum residue limit (MRL) for OTC and SDI, respectively. Conclusions: The results indicate that drug residue is common in raw beef samples and a good proportion of beef samples exceeded MRL. Farmer’s education to ensure rational use of antibacterials and to follow withdrawal period may help control this public health hazards in Bangladesh context.

Hazards and Detection Techniques of Veterinary Drug Residues in Animal-Origin Food

Veterinary drugs originally used to diagnose, prevent, control and treat animal diseases. However, now some of them can also be mixed into livestock feed as growth promoters. Although most countries have specified animal-derived veterinary drug residue standards, such as the maximum residue limit, withdrawal period and prohibition of some veterinary drugs as growth promoters, there are still some animal-derived products with illegal amount of drug residues. Consequently, long-term intake of products with excessive residues will result in irreversible impacts on human health, livestock industries and natural environment. To minimize these risks, the techniques of drug residues detection plays an important role in guarding food safety of animal products. Moreover, Veterinary drug residue detection technology, according to the author's opinion, can be divided into instrumental method, immunoassay method, biomolecular technology and bio-sensor technology. The purpose of this article is to collect and summarize the existing journal literature current about status, hazards and detection techniques of animal-origin veterinary drug residues so that ordinary readers can briefly understand the research status of the residue detection techniques, farmers can understand the importance of regulating and suitable handling of veterinary drugs, and relevant researchers may know about the emphasized difficulties that need to be overcome in drug residue detection techniques.

A Survey of 61 Veterinary Drug Residues in Commercial Liquid Milk Products in China

ABSTRACT To investigate the drug residue status in commercial liquid milk products in China, 190 samples, including ultrahigh temperature milk (n = 168) and pasteurized milk (n = 22) samples, were collected in 2019. Milk samples were analyzed for the presence of any of the 61 veterinary drugs in them by using a screening assay combined with an ultraperformance liquid chromatography–tandem mass spectrometry analysis. Ten (5.26%) samples were found positive for β-lactams, tetracyclines, and aminoglycosides, and six (3.16%) samples were confirmed residual for penicillin G (n = 6; 3.16%), tetracycline (n = 1; 0.53%), and oxytetracycline (n = 1; 0.53%), with the maximum concentration of 2.85, 40.64, and 12.35 μg kg−1, respectively. Drug residue detection rate in group II (4.55%; the local city domestic brands) was higher than that in group I (2.70%; the major brands of China) and group III (2.78%; the imported brands into China) and higher in domestic samples (3.39%) than that in imported samples (2.78%), and higher in pasteurized milk samples (9.09%) than in ultrahigh temperature milk samples (2.38%). All drug residue levels were far below the regulated maximum residue limits. However, based on some veterinary drug residues detected in the samples, there is a potential veterinary drug risk in liquid milk products in the Chinese market, and this situation deserves the attention of governments and consumers. HIGHLIGHTS