Veterinary Research Forum

Abstract Avian Salmonellosis impacts the economy and public health, with chicken products being a major cause of gastroenteritis. Hygiene, immunization and medicines are all used as control techniques. Bacteriophages provide a safe, targeted alternative. In the present study in vitro evaluation of bacteriophages were done against Salmonella typhimurium. Lytic effect of bacteriophages isolated from poultry sludge was checked on culture of S. typhimurium. Stability study was checked at range of temperature and pH. The phages were stable at temperature (30.00 - 50.00 ˚C) and pH (5.00 - 9.00) where best activity was seen at 37.00 ˚C and pH 7.00. In vitro lytic activity was done at (optical density 600 nm) after exposure to bacterial host at different intervals. Multiplicity of Infection of 1.00 was used to check lytic activity of phages which indicated phages were potent enough to infect bacterial cells within their growth cycle. The percentage of unadsorbed phages was determined by bar chart analysis. The genome of three phages was treated with DNase I where they all were sensitive. Later the nucleic acid of phages was digested by restriction endonucleases (EcoRI and HindIII) both of the enzymes produced various restriction sites with different band. The present study proved that the application of bacteriophages in vitro into bacterial system i.e., S. typhimurium was an attractive method in diminishing infection in commercial poultry thus providing exceptional results that could be used on a large scale.

Abstract This study was conducted to determine the effect of different cage densities and meat storage periods on some meat quality parameters in drumstick and breast meat of brown and white spent hens. The study used three different cage densities as low (5 hens per cage), normal (seven hens per cage) and high (10 hens per cage) including 396 hens as 198 Hy-Line Brown (HB) and 198 Isa Tinted (IT). The feeding of chickens was ad libitum (20 - 60 weeks). At the end of the study, a total number of 54 chickens (27 HB and 27 IT) were slaughtered. Some chemical and microbiological analyses were carried out by separating the drumstick and breast area of the slaughtered chickens. According to the results of the research, the redness and yellowness values of the breast area were higher in the ITs. The effect of cage density was significant only for yellowness in the drumstick area. The effects of storage time, lightness and yellowness in the drumstick area and lightness value in the breast area were found to be significant. Bacterial density and thiobarbituric acid reactive substances values of both breast and drumstick regions of spent hens were higher in HBs, while pH values were higher in ITs. The bacterial density in the meat was increased during the storage period. In conclusion, cage density, genotype and storage time affected the microbiological and chemical quality of spent chicken meat. With this result, it can be said that meat quality studies, which mostly focus on broilers, are also important in spent hens.

Abstract The red mite of poultry, Dremanyssus gallinae, is the most important hematophagous ectoparasite of poultry. In this study, pathologic changes of its biting on the poultry skin have been investigated. Thirty-two (Control = 16 and Treatment = 16) four weeks old Ross broilers (308) were infested with the mite on skin of hock joins. Samples were collected after 1, 24, 72 hours and 10 days. The skin samples were fixed in 10% buffered formalin and histological sections were prepared using routine Hematoxylin & Eosin staining method. Results showed that in all cases, except within first hour of infestation, lymphocytic infiltration was always a constant pathologic feature. Necrosis of feather's follicles was a prominent pathologic feature ensued due to vascular disturbances and resulted in loss of feather. Hyperkeratosis, parakeratosis and acanthosis were observed after 72 hours. These findings reveal that mite biting induces local epidermal hyperplasia.