Experimental ochratoxicosis in broiler chickens

Abstract

This study describes the toxicity signs that developed when the diet of male broiler chickens was artificially contaminated with different levels of the mycotoxin ochratoxin A (OTA). Chicks were assigned randomly to three groups of 80 chicks that were fed a diet containing 0 parts per billion (ppb) (control, group 1), 400 ppb (group 2) or 800 ppb (group 3) OTA from day 1 to 5 weeks of age. Signs of ochratoxicosis were assessed on the basis of changes in the following criteria: body weight, relative weights of two representative internal organs (gizzard and thymus), feed consumption, feed conversion ratio, mortality, thyroid activity, blood profile, humoral and cell mediated immunity. Feeding OTA at levels of 400 and 800 ppb (groups 2 and 3) significantly decreased the body weight, thymus weight, feed consumption, feed conversion ratio and thyroxine concentration (P B/0.05). The OTA groups developed anaemia manifested by a significant decrease in the red blood cell count, packed cell volume percentage and haemoglobin concentration (P B/0.05). By the end of the experiment both groups that received OTA showed a 37% reduction in red blood cell count compared with the control group. Furthermore, a significant decrease in the white blood cell count, humoral immune response and cell-mediated immunity was found in both groups fed ochratoxin compared with the control group (P B/0.05). The reduction in the above parameters was more noticeable with time and was proportional to the level of OTA exposure. A significant increase in relative gizzard weight, cumulative mortality and triiodothyronine concentration was found in OTA-fed chicks (P B/0.05). These data provide a description of ochratoxicosis in broilers that should be useful in diagnosis and in improved understanding of the practical implications on broiler performance and health, a problem that can threaten the poultry industry.

Immunological responses of male White Leghorn chicks kept on ochratoxin A (OTA)-contaminated feed

“…In the present study, the lymphoproliferative response to PHA-P was significantly lower (as compared to Group A) in the chicks kept on OTA-contaminated diets. The finding of our study is in line with results shown by Elaroussi et al (2006) that reported significant decreases in the skin thickness response to PHA-P in male broiler chicks kept on an OTA-contaminated ration (i.e., at 0.4 and 0.8 mg/Kg diet) for 5 weeks. The significant decrease in the thymus weight and depletion of lymphoid cells noted here-and also reported earlier by Elauorssi et al (2006), Al-Anati andPetzinger (2006), andDwividi andBurns (1985)-provide significant clues to allow us to better understand the depression in T-lymphocyte functions in OTA-treated birds.…”

“…A similar effect on broiler chick immune system organ weights-due to ochratoxicosis-was reported by Dwivedi and Burns (1984), Hanif et al (2008), and Awaad et al (2011). Feeding an OTA-contaminated (0.4 and 0.8 mg/Kg diet) diet to male broiler chicks from the day after hatching to 5 weeks-of-age resulted in the significant decrease in thymus weight (Elaroussi et al, 2006). This effect of OTA may be attributed to cytotoxic and degenerative changes in the lymphoid follicles (Al-Anati and Petzinger, 2006).…”

Mycotoxins in Poultry

“…Ochratoxins cause signiicant health problems and economic losses in poultry [26] and cause mycotoxic porcine nephropathy (MPN) [27]. Ochratoxin-related diseases are characterized by severe kidney damage, which could be overtly related to the exposure to ochratoxins, sometimes in combination with diferent mycotoxins [27].…”

Impacto das Fumonisinas, Aflatoxinas e Ocratoxina A na Avicultura

“…Os efeitos tóxicos incluem nefrotoxicidade, hepatotoxicidade (KUIPPER-GODMAN; SCOOT, 1989), teratogenicidade (WANGIKAR et al, 2004), imunotoxicidade (ELAROISSE et al, 2006) e carcinogenicidade. Além disso, é classificada como possivelmente carcinogênica para seres humanos (categoria 2B) pelo IARC (1993).…”

“…Frangos de corte alimentados com ração artificialmente contaminada com OTA (800 µg Kg -1 ) durante cinco semanas, apresentaram redução do peso corpóreo, do consumo de ração, além de diminuição da taxa de conversão alimentar e aumento da mortalidade (ELAROISSE et al, 2006). Sakthivelan e Rao (2010) contaminaram rações destinada a frangos de corte com OTA em concentrações de 1000 a 2000 µg Kg -1 e também relataram redução da taxa de crescimento, da ingestão de ração, da conversão alimentar, além da redução de proteínas séricas e albumina.…”