Muhammad Kashif Saleemi

Residues of aflatoxin B1 in broiler meat: effect of age and dietary aflatoxin B1 levels.

This study describes the effect of dietary levels of aflatoxin B1 (AFB1) and age of the birds upon the residue level in liver and muscles of broiler chicks. In three different experiments broiler chicks of 7, 14 and 28 days of age were kept for 7 days on contaminated rations having 1600, 3200 and 6400 μg/kg AFB1. AFB1 residues were detected earlier in younger birds and those fed high AFB1 dietary levels. The highest residue levels in liver and muscles of young chicks fed 6400 μg/kg AFB1 was 6.97±0.08 and 3.27±0.05 ng/g, respectively. Maximum residue concentration was high in birds of young age and those kept on high AFB1 ration. After withdrawal of AF contaminated rations, residues clearance was slow and AFB1 was detectable in liver and muscles of birds for longer duration in younger birds and those fed high AFB1 dietary levels. AFB1 residues in poultry tissues may buildup to high levels in areas with no regulatory limits on AFB1 levels of poultry feed and may pose a risk to consumers health.

Anticoccidial drug resistance in fowl coccidia: the state of play revisited

The development of drug resistance in Eimeria is common because of extensive use of anticoccidial drugs for the control of avian coccidiosis. The significance of chemotherapy is evident from the fact that, in spite of advancement in the field of immunological, biotechnological and genetic methods, prophylactic chemotherapy with anticoccidial drugs is still widely used for the control of coccidiosis. In such situations, new drugs should be available to replace the older ones against which resistance has developed, however it takes a long time to develop any new compounds. It is therefore currently necessary to develop strategies to minimise the emergence of resistance in Eimeria strains and to prolong the effect of available anticoccidial drugs. This paper summarises the resistance status of Eimeria species in different parts of the world and reviews different types of resistance, mechanism of resistance development, factors involved in the development and spread of resistance, management of resistant strains and strategies to preserve the efficacy of the available anticoccidial drugs. Use of vaccines, synthetic and botanical anticoccidials and educating farmers about recommended coccidiosis control practices are discussed in this review, along with the integration of currently available options for the management of drug resistance and, ultimately, the control of coccidiosis.

Toxico-pathological changes induced by cypermethrin in broiler chicks: their attenuation with Vitamin E and selenium.

Ninety 1-day old broiler chicks of mixed gender (as hatched) procured from a local hatchery were randomly divided into five equal groups. All the treatments were given through crop tubing. Groups 1-4 received cypermethrin (CY) (600mgkg(-1)b. wt.) daily for 30 days. In addition to CY (group 1), groups 2-4 received Vit E (150mgkg(-1)b. wt.), Se (0.25mgkg(-1)b. wt.), and Vit E (150mgkg(-1)b. wt.)+Se (0.25mgkg(-1)b. wt.), respectively. Group 5 served as control andreceived normal saline (2mlkg(-1)b. wt.) for 30 days. Randomly selected six broiler chicks from each group were slaughtered at experimental days 10, 20 and 30 for the collection of serum/plasma and morbid tissues. Absolute organ weights were recorded. Total plasma proteins, fibrinogen and creatinine were significantly (P<0.05) increased while alkaline phosphatase (ALP), lactate dehydrogenase (LDH) and urea decreased significantly (P<0.05) in CY-treated group when compared with the control group. Kidneys were swollen grossly in treated broiler chicks. In liver, necrosis of hepatocytes, cytoplasmic vacuolation, bile duct hyperplasia and mononuclear cellular infiltration were observed. In kidneys, necrosis of tubular epithelial cells, cytoplasmic vacuolation, cellular infiltration and atrophy of glomeruli were observed. Sub-arachnoid space was much dilated in CY-treated broiler chicks. It can be concluded that CY induces biochemical and histopathological alterations in broilers chicks; however, these toxic effects can be ameliorated by Vit E or Se. Combination of Vit E and Se was more effective in ameliorating toxic effects of cypermethrin in broilers chicks.

Clinico-hematological and micronuclear changes induced by cypermethrin in broiler chicks: Their attenuation with vitamin E and selenium

This study was carried out on 90 one-day-old broiler chicks to know clinico-hematological alterations, DNA damage caused by cypermethrin (CY), and attenuation of toxic effects by vitamin E (Vit E) and selenium (Se). Birds were randomly divided into five equal groups. Groups 1-4 received CY (600mlkg(-1)b.wt) daily for 30 days by crop tubing. In addition to CY, groups 2, 3 and 4 received Vit E (150mgkg(-1)b.wt), Se (0.25mgkg(-1)b.wt), and Vit E (150mgkg(-1)b.wt)+Se (0.25mgkg(-1)b.wt), respectively. Group 5 served as control. Birds were monitored twice daily for clinical signs. They were weighed and blood samples were collected at experimental days 10, 20 and 30 for hematological studies. CY-treated birds showed more prominent signs of toxicity compared to CY+Vit E, CY+Se and CY+Vit E+Se birds. Body weight in groups 1-3 was significantly (P<0.05) smaller at days 20 and 30 when compared with the control group. Significantly (P<0.001) higher numbers of micronuclei appeared in chicks treated with CY compared to CY+Vit E- and CY+Se-treated birds. Significantly decreased total erythrocyte counts (TEC), hemoglobin (Hb) concentration and packed cell volume (PCV) in all treated groups were recorded. Treated birds suffered from macrocytic hypochromic anemia. Leukocytosis in early stage and later leucopenia was seen in treated birds. It can be concluded that CY induces toxic effects in broilers chicks; however, these toxic effects can be ameliorated by Vit E or Se. Combination of Vit E and Se was more effective to ameliorate toxic effects of cypermethrin.

Amelioration of Ochratoxin A-induced immunotoxic effects by silymarin and vitamin E in White Leghorn cockerels

Silymarin (SL) is the bioactive extract of the plant Silybum marianum and Vitamin E (VE) is an important anti-oxidant. The present study was designed to evaluate potential ameliorative effects of SL and VE against Ochratoxin A (OTA)-induced immunotoxic effects in White Leghorn cockerels. One day-old birds were divided into 12 groups (20 birds/group) and fed basal diets amended with OTA (1.0 or 2.0 mg/kg) alone or in combination with SL (10 g/kg) and/or VE (200 mg/kg) for 42 days. Immunological in situ responses, including antibody formation against sheep red blood cells (7 and 14 days after both primary and booster injections), lymphoproliferative responses to avian tuberculin (30 days of age), and mononuclear phagocytic system function (i.e. by clearance of injected carbon particles) assay (42 days of age), were assessed. Results suggested that silymarin and Vitamin E alone or in combination ameliorated the immunotoxic effects induced by 1.0 mg OTA/kg but could not significantly impact on the effect from ingestion of 2.0 mg OTA/kg. The results of the present study suggested that both SL and VE possess an ability to ameliorate OTA-induced immunotoxicity in chicks. However, it remains to be determined whether/what SL:OTA or VE:OTA ratios are required to assure such mitigation of OTA-induced immunotoxicities.

Anticoccidial effects of acetic acid on performance and pathogenic parameters in broiler chickens challenged with Eimeria tenella

The objective of the present study was to evaluate the anticoccidial effect of the different concentrations of the acetic acid in the broiler chickens in comparison with the amprolium anticoccidial. A total of 198 chicks were placed 11 per pen with three pens per treatment. The different concentrations (1%, 2% and 3%) of acetic acid and amproilum (at the dose rate of 125ppm) were given to the experimental groups in drinking water from 10-19th days of age. One group was kept as infected non medicated control and one as non infected non medicated control. All the groups were inoculated orally with 75,000 sporulated oocysts at the 12th day of age except non infected non medicated control. Anticoccidial effect was evaluated on the basis of performance (weight gain, feed conversion ratio) and pathogenic (oocyst score, lesion score and mortality %age) parameters. Among acetic acid medicated groups, the maximum anticoccidial effect was seen in the group medicated with 3% acetic acid followed by 2% and 1% acetic acid medicated groups. Amprolium and 3% acetic acid were almost equivalent in suppressing the negative performance and pathogenic effects associated with coccidiosis (Eimeria tenella) challenge. In summary, acetic acid has the potential to be used as alternative to chemotherapeutic drugs for Eimeria tenella control. Concentration-dependent anticoccidial effect of acetic acid suggests that further studies should be carried out to determine the possible maximum safe levels of acetic acid with least toxic effects to be used as anticoccidial.

Toxico-Pathological Effects of In Ovo Inoculation of Ochratoxin A (OTA) in Chick Embryos and Subsequently in Hatched Chicks

This study was designed to investigate the toxico-pathological effects of in ovo inoculation of ochratoxin A (OTA) in chicken embryos and subsequently in the hatching chicks. Nine hundred fertile white leghorn (WL) layer breeder eggs were divided into eight groups (A–H). Group A was maintained as untreated control, whereas group B was kept as sham control (10 µL of 0.1 M NaHCO3 solution). Before incubation, groups C, D, E, F, G, and H were injected with 0.01, 0.03, 0.05, 0.10, 0.50, and 1.00 µg OTA/egg, respectively. At 53 hrs of incubation, crown to rump length, optic cups, and eye lens diameters were significantly (p ≤ .05) lower, whereas neural tube closure defects were higher in the OTA-treated embryos. Teratogenic defects (studied at day 9 of incubation) and embryonic mortalities were higher in the groups administered high doses of OTA. A significant increase was noted in the serum concentration of ALT, urea, and creatinine, along with higher weights of liver and kidney, in chicks hatched from OTA-contaminated eggs. These findings suggested that there are teratogenic and substantive toxicological risks in the developing chicken embryos and hatched chicks that could be exposed to OTA in ovo.

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

This study was designed to evaluate some immunological responses of male White Leghorn (WL) chicks kept on an ochratoxin A (OTA)-contaminated diet. For this purpose, 350 1-day-old male WL chicks were divided into five groups (A–E). Group A was kept as control, while Groups B, C, D, and E were fed OTA-contaminated feed at 0.1, 0.5, 1.0, and 1.5 mg/Kg diet, respectively, for 21 days, and then basal ration for the remaining period. At 14- and 16-days of age, random chicks (n = 10) from each group were used for analyses of phagocytic function of the reticuloendothelial system or for measuring the lymphoproliferative responses to intradermally-administered T-cell mitogen, phytohemagglutinin-P (PHA-P), respectively. At 30-days of age, abdominal macrophages were collected from 15 chicks/group and utilized for determination of their phagocytic potential and for nitrite production. Antibody (Ab) titers (i.e., total antibodies, IgM, and IgG) against sheep red blood cells (SRBC) were determined at 7 and 14 days after a primary (at 7 days of age) and a booster (given 14 days after primary [at 21-days of age]) dose (intravenous) of the antigen. Data from the present study showed that the relative weight of the bursa of Fabricius of chicks fed OTA for 14 and 21 days and the spleen of chicks fed OTA for 21 days were significantly lower than their control counterpart. Phagocytic function of reticuloendothelial system evaluated by carbon clearance, and lymphoproliferative response to PHA-P, of chicks kept on OTA-contaminated diet were significantly lowered. The percentage of abdominal macrophages displaying phagocytosis of SRBC, the number of SRBC/macrophage, and nitrite production were each significantly lower in cells from chicks in the OTA-fed groups. Total Ab (at days 7 and 14 post-booster SRBC injection) and IgG (at day 14 post-primary and day 7 post-booster SRBC injection) titers against SRBC showed significant reductions in the groups fed OTA-contaminated diet. The findings of this study are in line with the previous work suggesting the immunosuppressive effect of OTA in male WL chicks regarding functional impairment in some of the components of the immune system.

Immunological status of White Leghorn chicks hatched from eggs inoculated with ochratoxin A (OTA).

This study was designed to evaluate the immunological status of chicks hatched from the ochratoxin A (OTA)-contaminated eggs. For this purpose, 900 fertile White Leghorn (WL) layer breeder eggs were divided into eight groups (A–H). Group A was maintained as untreated control, whereas Group B was kept as sham control (10 µL of 0.1 M NaHCO3). Groups C, D, E, F, G, and H were injected with 0.01, 0.03, 0.05, 0.10, 0.50, and 1.00 µg OTA/egg, respectively. Eggs were incubated at 37.5°C and 65% relative humidity. Hatched chicks from each group were then maintained separately under standard environmental conditions. At Day 18-of-age, chicks (n = 10) from each group were used for lymphoblastogenic response against an intradermal administration of phytohemagglutinin P (PHA-P). At Day 30-of-age, abdominal macrophages, collected from 15 chicks in each group, were utilized for determination of phagocytic potential using sheep red blood cells (SRBC) as particulate antigen and for nitrite production in response to lipopolysaccharide. Antibody (Ab) titers (i.e. total antibodies, IgG, and IgM) against SRBC were determined at 7 and 14 days after primary (at Day 13-of-age) and booster (given 14 days after primary) intravenously administered SRBC doses. The lymphoblastogenic responses of the chicks hatched from OTA-contaminated eggs in response to PHA-P administration were significantly lower at 24, 48, and 72 h after PHA-P injection when compared with responses by control chicks. The percentage of abdominal macrophages displaying phagocytosis of SRBC, the number of SRBC/macrophage, and nitrite production were each significantly lower in cells from chicks in the OTA-administered groups. Total Ab, IgG, and IgM titers against SRBC showed significant reductions in the groups that had been hatched from eggs injected with the higher doses of OTA (as compared with titers associated with chicks in control eggs). These findings suggested that there are substantive immunosuppressive risks in chicks that could be exposed to OTA in ovo.

Dietary vitamin E in White Leghorn layer breeder hens: a strategy to combat aflatoxin B1-induced damage

Mycotoxins are unavoidable contaminants of animal and human feed and food respectively. This study was designed to investigate the protective activity of vitamin E (Vit E) in White Leghorn breeder hens and their progeny against aflatoxin B1 (AFB1)-induced damage. The results indicated a significant decrease in egg production and quality in the groups exposed to dietary AFB1. A detectable amount of AFB1 residue appeared in the eggs during the first week of mycotoxin exposure at levels ≥ 2.5 mg kg−1, which reached its peak (0.403 ± 0.04 ng/g [mean ± standard deviation]) during the second week of the experiment (in the group fed 10 mg kg−1). Feeding Vit E + AFB1 resulted in higher AFB1 residues (0.467 ± 0.03) when compared with the hens fed AFB1 alone. The resistance of red blood cells to oxidative damage was decreased, while embryonic mortalities and deformities were increased in the AFB1-fed groups. The protective effect of Vit E on these parameters was noted in the groups fed lower doses of AFB1. After the withdrawal of mycotoxin-contaminated feed, most of the parameters returned towards normal within 2 weeks, except AFB1 residues that were still detectable. From the findings of this study one can conclude that the addition of Vit E in the diet of hens provided only partial protection against AFB1-induced damage.