Closantel plasma and milk disposition in dairy goats: assessment of drug residues in cheese and ricotta

Abstract

Closantel (CLS) is currently used in programs for the strategic control of gastrointestinal nematodes. CLS is extralabel used in different dairy goat production systems. From available data in dairy cows, it can be concluded that residues of CLS persist in milk. The current work evaluated the concentration profiles of CLS in plasma and milk from lactating orally treated dairy goats to assess the residues pattern in dairy products such as cheese and ricotta. Six (6) female Saanen dairy goats were treated orally with CLS administered at 10 mg/kg. Blood and milk samples were collected between 0 and 36 days post-treatment. The whole milk production was collected at 1, 4, 7, and 10 days post-treatment to produce soft cheese and ricotta. CLS concentrations in plasma, milk, cheese, whey, and ricotta were determined by HPLC. The concentrations of CLS measured in plasma were higher than those measured in milk at all sampling times. However, the calculated withdrawal time for CLS in milk was between 39 and 43 days postadministration to dairy goats. CLS residual concentrations in cheese (between 0.93 and 1.8 μg/g) were higher than those measured in the milk used for its production. CLS concentrations in ricotta were sixfold higher than those in the milk and 20-fold higher than those in the whey used for its production. The persistent and high residual concentrations of CLS in the milk and in the cheese and ricotta should be seriously considered before issuing any recommendation on the extralabel use of CLS in dairy goat farms.

Determination of the presence of pathogens and anthelmintic drugs in raw milk and raw milk cheeses from small scale producers in Ireland

“…This was seen with residues in milk that remained in dairy products and in some cases increased (Iezzi et al, 2014).…”

The Pattern of Blood–Milk Exchange for Antiparasitic Drugs in Dairy Ruminants

“…Moreover, CLS is an extra-label used in different dairy production systems. CLS is widely bound to plasma proteins (>99%) and has a long terminal half-life of 14.3-14.5 days in sheep [100,105] and 8.9 days in dairy goats [106]. As a consequence of its high plasma protein binding, the duration of therapeutic levels of CLS in plasma is prolonged, which limits the distribution to tissues [107,108].…”

“…As a consequence of its high plasma protein binding, the duration of therapeutic levels of CLS in plasma is prolonged, which limits the distribution to tissues [107,108]. The elimination half-life being shorter in dairy goats [106] compared with other animal species [100,105] could be attributed to the differences in the turnover of albumin.…”

Closantel Suppresses Angiogenesis and Cancer Growth in Zebrafish Models

“…23 In this study, we have taken advantage of the Tg (fli1a: EGFP) zebrafish line, 24 in which the vascular system is visible through endothelium-specific enhanced green fluorescent protein (EGFP) expression, to screen old drugs for antiangiogenic activity from the U.S. Drug Collection Library. We identified 11 positive hits, one of the most potent being Closantel, which is a veterinary drug used as an anthelmintic for cattle, sheep, and goats, 25 and has not been previously reported to display antiangiogenic activity in a dosedependent manner. Furthermore, Closantel demonstrated in vivo anticancer potential in zebrafish xenotransplanted with a variety of human cancer cells.…”