Accidental poisoning of 17 dogs with lasalocid

The In Vitro Cytotoxic Effects of Ionophore Exposure on Selected Cytoskeletal Proteins of C2C12 Myoblasts

Carboxylic ionophores, such as monensin, salinomycin and lasalocid, are polyether antibiotics used widely in production animals for the control of coccidiosis, as well as for the promotion of growth and feed efficiency. Although the benefits of using ionophores are undisputed, cases of ionophore toxicosis do occur, primarily targeting the cardiac and skeletal muscles of affected animals. The 3-[4,5-dimethylthiazol-2yl]-2,5-diphenyl tetrazolium bromide (MTT) viability assay was used to determine the cytotoxicity of monensin, salinomycin and lasalocid on mouse skeletal myoblasts (C2C12). Immunocytochemistry and immunofluorescent techniques were, in turn, performed to investigate the effects of the ionophores on the microfilament, microtubule and intermediate filament, i.e., desmin and synemin networks of the myoblasts. Monensin was the most cytotoxic of the three ionophores, followed by salinomycin and finally lasalocid. Monensin and salinomycin exposure resulted in the aggregation of desmin around the nuclei of affected myoblasts. The synemin, microtubule and microfilament networks were less affected; however, vesicles throughout the myoblast’s cytoplasm produced gaps within the microtubule and, to a limited extent, the synemin and microfilament networks. In conclusion, ionophore exposure disrupted desmin filaments, which could contribute to the myofibrillar degeneration and necrosis seen in the skeletal muscles of animals suffering from ionophore toxicosis.

Anticoccidial drugs of the livestock industry

Coccidiosis is a parasitic disease of a wide variety of animals caused by coccidian protozoa. The coccidia are responsible for major economic losses of the livestock industry. For example, the annual cost due to coccidiosis to the global poultry industry has been estimated to exceed US$ 3 billion annually. Currently available drugs for the control of this disease are either polyether ionophorous antibiotics that are derived from fermentation products, or synthetic compounds, produced by chemical synthesis. Unfortunately, no new drugs in either category have been approved for use for decades. Resistance has been documented for all those of the drugs currently employed and therefore the discovery of novel drugs with unique modes of action is imperative if chemotherapy is to remain the principal means to control this disease. This chapter aims to give an overview of the efficacy and mode of action of the current compounds used to control coccidiosis in livestock and provides a brief outlook of research needs for the future.

Diagnosis and Treatment of Lower Motor Neuron Disease in Australian Dogs and Cats

Diseases presenting with lower motor neuron (LMN) signs are frequently seen in small animal veterinary practice in Australia. In addition to the most common causes of LMN disease seen world-wide, such as idiopathic polyradiculoneuritis and myasthenia gravis, there are several conditions presenting with LMN signs that are peculiar to the continent of Australia. These include snake envenomation by tiger (Notechis spp.), brown (Pseudonaja spp.), and black snakes (Pseudechis spp.), tick paralysis associated with Ixodes holocyclus and Ixodes coronatus, and tetrodotoxins from marine animals such as puffer fish (Tetraodontidae spp.) and blue-ring octopus (Hapalochlaena spp.). The wide range of differential diagnoses along with the number of etiological-specific treatments (e.g., antivenin, acetylcholinesterase inhibitors) and highly variable prognoses underscores the importance of a complete physical exam and comprehensive history to aid in rapid and accurate diagnosis of LMN disease in Australian dogs and cats. The purpose of this review is to discuss diagnosis and treatment of LMN diseases seen in dogs and cats in Australia.

Acute polyneuromyopathy with respiratory failure secondary to monensin intoxication in a dog

OBJECTIVE

To describe a successfully managed case of polyneuropathy and respiratory failure secondary to presumed monensin intoxication.

CASE SUMMARY

A 9-month-old Australian Shepherd was evaluated for progressive generalized weakness and respiratory distress. Several days preceding presentation, the dog was seen playing with a monensin capsule, and had free access to a barn where the product was stored and where chewed capsules were subsequently found. The dog was presented with flaccid tetraparesis, hyperthermia, and severe respiratory distress. Bloodwork and urinalysis revealed marked increase in serum creatine kinase concentration and presumed myoglobinuria. Cardiac troponin I level was markedly increased. Management included mechanical ventilation for 5 days, fluid-therapy, active cooling, antimicrobial therapy, analgesia, gastroprotectants, antiemetics, enteral feedings, continuous nursing care, and physiotherapy. Intravenous lipid rescue therapy was administered with lack of improvement in respiratory function and muscle strength. The patient completely recovered and was discharged after 12 days of hospitalization.

NEW OR UNIQUE INFORMATION PROVIDED

Monensin intoxication should be considered in the differential diagnosis of acute polyneuromyopathy and respiratory failure in dogs with access to this compound. Respiratory failure secondary to monensin intoxication does not necessarily carry a poor prognosis if mechanical ventilation can be provided as a bridge until return of respiratory function is achieved.

Recent trends in common chemical feed and food contaminants in Israel

In February 2014 a new law was approved by the Israeli parliament, namely the Control of Animal Feed Law. The law intends to regulate the production and marketing of animal feed. In preparation for the law's implementation in 2017, we have assessed the current feed and food safety challenges in Israel in recent years in association with the presence of common undesirable contaminants in various common feed and food commodities. Tight collaboration between regulatory authorities and feed/food industry, enhanced feed and food quality monitoring, transparency of survey results and readily accessible and reliable information for the public about health hazards of chemical contaminants, will guarantee the safety and quality of food and feed.

The new Israeli feed safety law: challenges in relation to animal and public health

The Israeli feed safety legislation, which came to prominence in the early 1970s, has undergone a major change from simple feed safety and quality regulations to a more holistic concept of control of feed safety and quality throughout the whole feed production chain, from farm to the end user table. In February 2014, a new law was approved by the Israeli parliament, namely the Control of Animal Feed Law, which is expected to enter into effect in 2017. The law is intended to regulate the production and marketing of animal feed, guaranteeing the safety and quality of animal products throughout the production chain. The responsibility on the implementation of the new feed law was moved from the Plant Protection Inspection Service to the Veterinary Services and Animal Health. In preparation for the law's implementation, we have characterized the various sources and production lines of feed for farm and domestic animals in Israel and assessed the current feed safety challenges in terms of potential hazards or undesirable substances. Moreover, the basic requirements for feed safety laboratories, which are mandatory for analyzing and testing for potential contaminants, are summarized for each of the contaminants discussed. © 2016 Society of Chemical Industry.

Risk assessment of coccidostatics during feed cross-contamination: animal and human health aspects

Coccidiosis, an intestinal plasmodium infection, is a major infectious disease in poultry and rabbits. Eleven different coccidiostats are licensed in the EU for the prevention of coccidiosis in these animal species. According to their chemical nature and main biological activity, these compounds can be grouped as ionophoric (monensin, lasalocid sodium, salinomycin, narasin, maduramicin and semduramicin) or non-ionophoric (robenidine, decoquinate, nicarbazin, diclazuril, and halofuginone) substances. Coccidiostats are used as feed additives, mixed upon request into the compounded feed. During the technical process of commercial feed production, cross-contamination of feed batches can result in the exposure of non-target animals and induce adverse health effects in these animals due to a specific sensitivity of mammalian species as compared to poultry. Residue formation in edible tissues of non-target species may result in unexpected human exposure through the consumption of animal products. This review presents recent risk assessments performed by the Scientific Panel on Contaminants in the Food Chain (CONTAM) of the European Food Safety Authority (EFSA). The health risk to non-target species that would result from the consumption of cross-contaminated feed with coccidostats at levels of 2, 5 or 10% was found to be negligible for most animal species with the exception of salinomycin and monensin in horses because of the particular sensitivity for which toxicity may occur when cross-contamination exceeds 2% and 5% respectively. Kinetic data and tissue analyses showed that residues of coccidiostats may occur in the liver and eggs in some cases. However, the level of residues of each coccidiostat in edible animal tissues remained sufficiently low that the aggregate exposure of consumers would not exceed the established acceptable daily intake (ADI) of each coccidiostat. It could be concluded that technical cross-contamination of animal feeds would not be expected to adversely affect the health of consumers.