Safe alternative anticoccidial drug to chemical feed additives are herbal extracts, because they don't results to tissue residue and drug resistance. In order to evaluate the effects of herbal extracts to control avian coccidiosis, 180 one-day-old broiler chickens were randomly divided into nine equal groups, as follows: (1) Biarum bovei (2) Nectaroscordum tripedale( 3) Dorema aucheri (4) Cichorium intybus (5) Prangos ferulaceae (6) diclazuril (7) Artemisia absinthium (8) infected control (9) uninfected control (each contains two groups). Administration of herbal extracts and supplementation of diclazuril was began 2 days before challenge and lasted for the duration of the experiment. The chicks of all the groups except uninfected control group were inoculated orally with sporulated oocysts (3 × 10(3) oocysts of Eimeria tenella) on the day 22 of age. The criteria employed were: body weight, feed conversion ratio, blood in feces, survival rate, lesion scoring, number of oocyst output per gram feces and histopathological changes. For histopathological evaluation, on day 12 post inoculation three birds from each group were randomly selected and humanly sacrificed. N. tripedale and diclazuril revealed better results in terms of growth performance, lesion score, extent of bloody diarrhea and oocyst count as compared to other herbal extracts. The increase in the severity of lesions was observed in groups of D. aucheri, A. absinthium, B. bovei, P. ferulaceae, C. intybus, diclazuril and N. tripedale, respectively. In conclusion, the current study showed that herbal extracts were effective in control of coccidiosis caused by the E. tenella infection.

Low-pathogenic avian influenza virus (H9N2) is circulating in the poultry industry of many countries in the Middle East and Asia, causing serious economic damage. In this study the clinical signs, antibody response, viral shedding and efficacy of oil emulsion vaccines in Chukar partridges were investigated until 9 days post inoculation (d.p.i.). Seventy-five Chukar partridges (Alectoris chukar) were divided randomly in three groups of challenged (Group C), vaccinated and challenged (Group VC) and control (non-vaccinated and non-challenged [Group NC]), 25 birds/group. Groups C and VC were inoculated with 0.4 ml allantoic fluid containing 10(7) median embryo infective dose/bird of A/Chicken/Iran/772/1998(H9N2) avian influenza virus. Clinical signs, antibody response, viral shedding and vaccine efficacy were evaluated and compared among these groups over 9 days. Clinical signs such as coughing and sneezing with depression and decreased feed and water consumption were observed in Group C. In Group VC only a slight decrease in food and water consumption was observed. Both Groups C and VC showed maximum antibody titre at 9 d.p.i. At 1 d.p.i. the virus was detected from all tissues in challenged group, but the virus was not detected from the spleen and caecal tonsil of Group VC. Group C showed the longest period of viral shedding in the trachea and kidney.

This study was conducted to assess efficacy of heat-stable I-2 vaccine against Newcastle diseases in vaccinated and vaccinated in contact birds group following challenge against virulent Newcastle disease (ND) virus in village chicken. Also, to assess whether birds that have been exposed to vaccine virus-shedding, birds were protected against mortality and clinical signs after infection with a virulent strain of the ND virus (NDV). One hundred fifty one-day-old native chickens were divided into seven groups (4 experimental groups of 30 birds/group and 3 control groups (unvaccinated unchallenged, challenged, and just vaccinated). Birds in experimental groups were vaccinated either via drinking water or as food carrier with thermostable I-2 vaccine and then challenged with virulent isolate of NDV (JF820294.1), and eight birds were added as in-contact birds to vaccinated groups. Following challenge, seven extra birds were added to each group as in contact with vaccinated and challenged birds. Survival rate, clinical signs, necropsy finding, and mean antibody titer were evaluated in different experimental and control groups. Birds vaccinated via drinking water showed 100% survival rate. However, birds vaccinated with food carrier vaccine showed less than 50% survival rate. Based on the results obtained from this study, it can be recommended that I-2 vaccination via drinking water can effectively prevent ND in village chicken, since I-2 strain has been able to transmit to non-vaccinated-sensitive birds more effectively than velogenic NDV.

Aims: The aims of this investigation were to compare the effects of Lactobacillus acidophilus addition as simple or microencapsulated (ME) probiotic and inulin as prebiotic to the broiler diet on the faecal viral shedding and immunization against avian influenza virus (AIV) with or without H 9 N 2 vaccination. Methods and Results: Simple or ME forms of Lact. acidophilus, inulin and combination of them as synbiotic were analysed for their ability to enhance immunity against H 9 N 2 AIV and to decrease faecal viral shedding in Cobb-500 broiler chicks. Our results indicated that probiotic as ME form can decrease haemagglutination inhibition (HI) titre significantly on days 34 in vaccinated trial (P < 0Á05). Also, the effects of ME form of probiotic are more remarkable on reduction of viral faecal shedding detected by RT-PCR. Conclusions: The study shows the significant role of microencapsulation on probiotic effects against H 9 N 2 AIV. Significance and Impact of the Study: The application of probiotics especially in the ME form could have the potential for stimulating the immune system, preventing influenza infection and consequently reduce faecal viral shedding of H 9 N 2 AIV.

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