Induction of Tibial Dyschondroplasia by Carbamate and Thiocarbamate Pesticides

Abstract

Tibial dyschondroplasia (TD) is a major poultry leg problem, the natural etiology of which is unknown. Certain dithiocarbamate pesticides such as tetramethyl thiuram disulfide (thiram) have been shown to induce the disease in chickens. Because many different carbamate and thiocarbamate chemicals are used in a number of agricultural, industrial, and household applications, the objective of this study was to determine whether all chemicals of these categories induce TD and whether there is a concentration-dependent relationship between the ingestion of these chemicals and the incidences and the severity of the disease. Week-old broiler chicks were fed diets containing thiram or other assorted carbamate and thiocarbamate pesticides mixed in feed for 24-48 hr between ages 8 and 10 days. The birds were killed on day 15 and the proximal tibial and tarsometatarsal growth plates were evaluated for the presence and severity of TD lesions. TD was distinguished by broadening of growth plates; upon histologic exam chondrocytes appeared to be shrunken and dead. When compared by including equimolar concentrations of these chemicals in the feed, the dithiocarbamates with more than two sulfide groups, such as disulfiram, ferbam, thiram, and ziram were potent inducers of TD, whereas those with two sulfides to no sulfide group appeared ineffective at inducing TD. Both thiram and ferbam also reduced the bird's body weights. Thiram increased the incidence and the severity of the disease, denoted by TD index, in a dose-dependent manner. These results suggest that inadvertent contamination of feed or litter with some of these or similar chemicals may cause leg problems in poultry.

Expression of Genes Encoding Matrilin-3 and Cyclin-I During the Impairment and Recovery of Chicken Growth Plate in Tibial Dyschondroplasia

“…It occurs as a contaminant in products being used for litter material and poultry feed, ultimately leading to leg problems in the poultry industry (13). In our study, TD was induced by thiram because of its high regularity and precision in causing the disease (14). We used this experimental model to understand the behavior of chondrocytes with its environment during the impairment and recovery of growth plate in TD.…”

Supporting-Electrolyte-Free Anodic Oxidation of Oxamic Acids into Isocyanates: An Expedient Way to Access Ureas, Carbamates, and Thiocarbamates

“…Carbamates, thiocarbamates, and ureas have found numerous applications across fields ranging from medicinal chemistry to materials chemistry. − They are mostly used to produce poly­(urea-urethanes) or PUreas, which are valuable polymers in the manufacture of flexible and rigid foams, coatings, and adhesives. , For instance, a biodegradable polymer, such as poly­(propylene carbonate), is a widely used packing material and medicinal material . Up to 24 million tons of polyurethane are produced annually, mainly using aromatic isocyanates, such as toluene diisocyanate (TDI) and diphenylmethane diisocyanate (MDI) .…”

Dithiocarbamate Toxicity - An Appraisal

“…With TD, the proximal growth plates of the tibia and tibio-tarsal bones fail to ossify leading to the retention of unresolved cartilage. Feeding post hatch chickens diets containing thiram 50-100 mg /kg feed for a day or two is sufficient to induce TD (Rath et al, 2004;2007b) (Figure 2). The incidence and severity of the disease is related to the age of the chicks; during the early phase of growth when the bones are fast growing, the effects are more severe.…”

“…The incidence and severity of the disease is related to the age of the chicks; during the early phase of growth when the bones are fast growing, the effects are more severe. Subsequent studies showed that the dimeric and trimeric analogs such as thiram, disulfiram, ferbam, and ziram would induce this defect, where as the monomeric DTC such as potassium dimethyl dithiocarbamate, sodium metam, or PDTC were ineffective or less potent in similar concentrations (Rath et al, 2004;2007b). The induction of TD by thiram is dose dependent.…”