Immuno-pathologic effects of oral administration of chlorpyrifos in broiler chicks.

This study sought to assess if chlorpyrifos (CPF) induced immunotoxic effects in orally-treated day-old broiler chicks. Groups of chicks received per os CPF diluted in xylene at 5, 10, and 20 mg/kg body weight (CPF-5, CPF-10, and CPF-20) orally daily for 15 days. Xylene and control groups received xylene alone (1 ml/kg BW) and physiological saline, respectively. At various times during/after the exposure regimens, different immune end-points were analyzed in the birds. Humoral immunity was examined by assessing antibody responses to sheep red blood cells. Cell-mediated immunity was measured via lymphoproliferative responses to avian tuberculin. Leukocyte phagocytic ability was measured using a carbon clearance assay. Results showed that CPF administered to broiler chicks caused a dose-dependent decrease in humoral immunity, cell-mediated immunity, and phagocytic activity. Dose- and time-related pathological changes were observed in bursa of Fabricius, spleen, and thymus in treated birds. These changes were mild, moderate, and severe, respectively, in the 5, 10, and 20 mg/kg CPF groups. The Bursa of Fabricius in treated birds showed increased inter-follicular connective tissue proliferation, severe moderate cytoplasmic vacuolation, edema, and degenerative changes such as pyknosis and fragmentation of nuclei that depleted the follicles of lymphoid cells. In the spleen, disorganization of follicular patterns, severe congestion, cytoplasmic vacuolation, degenerative changes, and hyperplasia of reticular cells were noted. The thymus in treated birds exhibited congestion, hyper-cellularity, and a presence of immature monocytes in the medullary region, as well as myoid cell necrosis. Taken together, these studies clearly demonstrated that chlorpyrifos could induce immunotoxicities in broiler birds.

Heavy metal residues in the milk of cattle and goats during winter season.

Cadmium (Cd), chromium (Cr), nickel (Ni) and lead (Pb) residues (mg/L) were determined in the milk of cattle and goats. The milk samples of cattle from area 1 have higher levels of residues than area 2; Cd 0.089 +/- 0.002 vs. 0.062 +/- 0.01 Cr 1.14 +/- 0.046 vs. 0.995 +/- 0.017 Ni 23.38 +/- 0.564 vs. 21.407 +/- 0.275 Pb 21.781 +/- 0.172 vs. 15.958 +/- 1.00. The residual levels of Cd (0.084 +/- 0.003) and Pb (42.687 +/- 0.051) have been found higher in goat milk. The Ni residues in cattle milk (22.395 +/- 0.988) are higher than in goat milk (19.522 +/- 0.011) while residues of Cr are non significantly different in both species.

Cutaneous form of pox infection among captive peafowl (Pavo cristatus) chicks.

The present study was carried out to investigate the epidemiology and lesions of avian pox in captive peafowl chicks. Overall values of morbidity, mortality and case fatality were 45.2%, 27.1% and 60.0%, respectively. The chicks of 9 to 12 weeks of age showed a significantly (P<0.001) higher prevalence rate than other age groups. The morbidity and mortality due to avian pox in peafowl chicks was significantly (P<0.001) reduced when kept in mosquito-proof cages and hatched under broody chicken hens. Morbidity due to poxvirus infection on the peafowl farm was 82%, 26% and 12% in successive years. This reduction might have been the result of the introduction of mosquito-proof nets after year 1, although this was not the subject of a controlled experiment. All of the peafowl chicks suffering from dry pox showed pustular and nodular lesions on eye lids, beak, legs and toes. Distribution of lesions in different body parts varied significantly (P<0.023). Lesion diameters were less than 1 cm (59.73%), 1 to 2 cm (23.75%) and more than 2 cm (16.87%). Histopathological studies revealed extensive proliferation of subdermal connective tissue and infiltration of heterophils and macrophages. The keratinocytes showed degenerative changes in the form of cytoplasmic vacuolation, ballooning and hyper-chromatic nuclei. Eosinophilic intracytoplasmic inclusions (Bollinger bodies) in keratinocytes were consistently present. It was concluded that avian pox rendered high morbidity, mortality and case fatality in peafowl chicks.

Toxico-pathological effects in rats induced by concurrent exposure to aflatoxin and cypermethrin.

The objective of the present study was to explore modification in toxico-pathological responses of rats toward aflatoxins in the presence of cypermethrin. A total of 120 adult male rats divided into six equal groups received AF and cypermethrin alone or in different combinations. AF was administered daily into rats with a stomach tube at dose rates of 0, 0.5 and 1.0mg/kg AFB1. Cypermthrin was administered in the feed at dose levels of 0 and 500mg/kg. Rats administered AF alone showed depression, decrease in feed intake, body weight and loose feces. Livers exhibited fatty change, necrosis, newly formed bile ducts and increased diameter of hepatocytes and their nuclei. Lesions in kidney included tubular necrosis and pink homogeneous tubular casts. Serum ALT and creatinine concentrations increased while those of total proteins, albumin, serum cholesterol and triglycerides decreased. Rats fed cypermethrin only had decreased feed intake and body weight. Hepatocytes showed fatty change and cellular necrosis. A concurrent administration of AF with cypermethrin indicated a potentiation of the AF toxicity reflected by increased severity of clinical signs, mortality of the rats and decreased body weights. Kidneys' relative weight also showed an equivocal interaction between the two toxicants. Other parameters studied did not show significant differences between the rats administered AF alone or concurrently with cypermethrin.

Toxicological effects of diclofenac in four avian species.

The objective of the present study was to investigate the toxico-pathological effects of diclofenac in different avian species including broiler chicks (Gallus gallus, 15 days old), pigeons (Columba livia, 3 months old), Japanese quail (Coturnix japonica, 4 weeks old) and mynah (Acridotheres tristis, independent young). For each species, five groups each containing 10 birds were maintained and administered diclofenac sodium orally at dose rates of 0, 0.25, 2.5, 10 and 20 mg/kg body weight, respectively, for seven consecutive days. Clinical signs in all species included depression, somnolence, decreased body weight and mortality. Severity of clinical disease increased in a dose-related manner and was most severe in broiler chicks, followed by pigeons, Japanese quail, and was least severe in mynah. Serum creatinine levels were elevated in all species. Serum urea levels varied non-significantly in broiler birds, significantly decreased in pigeons and significantly elevated in Japanese quail and mynah. Broiler chicks and pigeons administered 10 and 20 mg diclofenac/kg had visceral gout; however, this was not observed in Japanese quail and mynah. The kidneys and liver were enlarged in all species. Histologically, the kidneys of all species showed acute renal necrosis and the livers had fatty change and necrosis of hepatocytes. The kidneys and liver of broiler chicks and pigeons given 10 and 20 mg/kg diclofenac also exhibited uric acid crystal aggregates (tophi) and associated lesions in the parenchyma.