Antioxidant and anticoccidial effects of garlic powder and sulfur amino acids on Eimeria-infected and uninfected broiler chickens

To study the anticoccidial and antioxidant effects of garlic powder [GP] and total sulfur amino acid [TSAA] on growth performance, faecal oocyst output, oxidative stress indicators and antioxidant status markers in broiler chickens, a 2 × 2 × 2 splitplot- factorial arrangement of treatments was used. A total of 480-day-old male broiler chickens were equally assigned to two plots. Two hundred forty chickens were challenged with Eimeria oocysts species mix by oral inoculation at day 34 [infected plot] and the other half was left unchallenged. In each plot, chickens were r and omly assigned to four treatments with 5 replicates of 12 birds each, and fed one of the following diets: basal diet, basal diet plus 0.5% GP, basal diet plus 50% more TSAA, basal diet plus 0.5% GP and 50% more TSAA. The results showed that inoculation with 7.5 × 102 oocysts of Eimeria mixed species significantly reduced growth performance [P<0.05] and increased nitric oxide [NO] and malonyldialdehyde [MDA], but did not change the hepatic activity of superoxide dismutase [SOD] and the glutathione peroxidase [GPX] activity. Growth depression and increased NO and MDA were greater in infected than uninfected birds. In the infected birds fed with the basal diet without any supplementation, NO and MDA were significantly greater [P<0.05] in comparison with other groups. Faecal oocyst output significantly decreased with the supplementation of GP and TSAA in infected birds [P<0.05]. In conclusion, the supplementation of GP and 50% TSAA individually or in combination with the basal diet significantly improved ADG [P<0.05] and decreased OPG, MDAandNO. Moreover, no changes in the antioxidant enzymes were observed in birds infected with Eimeria. Key words: Coccidiosis, Broiler chickens, Oxidative stress, Garlic powder, Sulfurs amino acid

Phenotypic and genetic diversity of motile aeromonads isolated from diseased fish and fish farms

Samples from the kidney of 100 diseased fish with signs of haemorrhagic septicemiaand50 samples from outlet water of fish farms were taken aseptically and cultured. In the laboratory, 75 colonies of gram-negative bacteria were biochemically diagnosed as motile aeromonads in our Bacteriology Laboratory Unit using API 20E rapid identification system. The genotype identification using specific primers for 16S rDNA by PCR and direct sequencing of 28 Iranian motile aeromonads isolates were as follow: in diseased fish, Aeromonas hydrophila [3 isolates, 15%], A. veronii bv. sobria [8 isolates, 40%], A. bestiarum/piscicola [5 isolates, 25%], A. media [3 isolates, 15%], A. j and aei [1 isolate, 5%], A. aquariorum [0 isolate, 0%] and in water, Aeromonas hydrophila [0 isolate, 0%], A. veronii bv. sobria [6 isolates, 75%], A. bestiarum/piscicola [0 isolate, 0%], A. media [1 isolate, 12.5%], A. j and aei [0 isolate, 0%] and A. aquariorum [1 isolate, 12.5%]. Results of this study suggest that the incidence of motile aeromonads septicemia due to A. veronii bv. sobria is the most prevalent motile aeromonads. Nucleotide polymorphisms on the sequencing results of the 16S rDNA were detected as noticeable inter and intra-specific variation within the population of different aeromonads isolates. In total, 10-20 variant nucleotide positions in this region were observed among Aeromonas spp. Key words: Phenotype, Genotype, Motile aeromonads, Diseased fish, Fish farms

Seroepidemiology and molecular detection of Brucella infection in Iranian horses: a provincial study

Brucellosis is a febrile zoonotic infection and has worldwide distribution among humans as well as animals. Although the seroprevalence of brucellosis in various animals has been described in Iran, there is only one report on equine brucellosis in the region. This study was carried out to determine the seroprevalence of brucellosis in racing clubs and private horse owners in the south of Iran and risk factors associated with the disease in horses. 312 randomly selected equine serum samples were investigated for the presence of antibodies against Brucella genus, using slide agglutination by Rose Bengal plate test [RBPT], serum agglutination test [SAT] and 2-mercaptoethanol [2-ME] test, using whole cell antigen. PCR assay was also used for detection of clinically suspected cases. Most seropositive horses in this study were asymptomatic. The true seroprevalence of brucellosis was found to be 9.9, 8 and 7% by RBPT, SAT and 2-mercaptoethanol tests, respectively. All horses with history of clinical signs [3.2% of all samples] had RBPT, SAT and 2-mercaptoethanol positive results. It was also revealed that age, sex and a history of contact with ruminants had no effect on acquiring the infection in positive cases. In the PCR, one of the three horses with fistula withers produced amplicon of 450 bp fragment of wbo sequences specific to Brucella spp. field strain. This study showed the seroprevalence of brucellosis in horses of Fars province and it was indicated that the PCR assay may be helpful in detection of clinically suspected horses

Isolation and characterization of lactococcus garvieae from diseased rainbow trout [Oncorhynchus mykiss, Walbaum] cultured in Iran

A total of 200 moribund rainbow trout with clinical signs of a hyperacute haemorrhagic septicemia were collected from rainbow trout farms in Fars, Kohkiloyeh-Boyer Ahmad and Charmohal-Bakhtiari provinces in the south and southwest of Iran during summer 2002 to winter 2008 for detection of Lactococcus garvieae, the causative agent of lactococcosis. Fish kidney samples were cultured aseptically onto brain heart infusion agar plates and incubated at 25°C for 48 h. Using conventional biochemical tests, L. garvieae was detected from 32 fish [16% of total fish samples]. Additionally, isolates were confirmed as L. garvieae using a specific PCR assay based on 16S rDNA gene by producing a single band of 1107 bp. Partial analysis of 16S rDNA revealed 100% sequence similarity for all Iranian isolates and there was a close genetic relationship among these isolates and those previously reported from mullet in Taiwan [AF352166] and yellowtail in Japan [AB267897] based on GenBank data. Results of antibiogram tests on L. garvieae isolates showed a high susceptibility to erythromycin, enrofloxacin, chloramphenicol and clarithromycin. In pathogenicity tests, immersion of fish in a bacterial suspension of 6x10[5] colony forming unit/ml of L. garvieae in challenge experiments showed 60% mortality during 14 days post-infection. Experimentally, infected fish showed typical blackening of skin haemorrhages, exophthalmia and wide haemorrhages on viscera. The present study provides useful molecular and biochemical information for L. garvieae isolates in Iran compared with those from different hosts and geographic locations