h. kohram

Infectious pancreatic necrosis virus (IPNV) is one of the major worldwide leading causes of losses among different fish species, especially in salmonidae. In order to develop a vaccine (First stage), the VP2 gene from an Iranian IPNV isolate was amplified using polymerase chain reaction (PCR), inserted between SpeI and ScaI restriction sites of pNZ8150 expression vector under the control of NICE promoter, and transformed into electrocompetent Lactococcus lactis cells using electroporation method regarding production of a recombinant live vector vaccine in fish. The transformed L. lactis cells containing the highest copy of the recombinant plasmid, pNZVP2, were selected using high antibiotic concentration (100 μg/mL of chloramphenicol). These cells are expected to express high level of VP2 protein and consequently will be the best candidates for vaccine formulation. Restriction enzyme digestion using SpeI, colony PCR using gene specific primers and boiling method, and DNA sequencing confirmed construction of the recombinant expression vector, pNZVP2. The present research will pave the way for expression and oral delivery of not only IPNV antigens, but also, any other infectious agents via pNZ8150/L. lactis expression system, potentially as a novel platform for the development of oral delivery vaccines in fish.

Among the viral diseases in trout farming, viral hemorrhagic septicemia (VHS) could be mentioned as the most devastating worldwide viral infection. In the present investigation, the influence of the omy-miR-731 Antagomir pretreatment on VHS in rainbow trout was examined. Trout (20±1) g were examined in four main groups subdivided into three subgroups, including a negative control without any injection, a vehicle that received saline, a positive control that was infected by VHSV, and an experimental group that received omy-miR-731 Antagomir by injection, then they were challenged by VHSV. The survival rate, average weight gain, histopathology, Immunohistochemistry and Blood-brain barrier impermeability were assessed in each group. The survival rate and average weight gain in the positive control group was significantly decreased in comparison with other groups. Remarkable histopathological changes and virus detection by immunohistochemistry test were observed in the positive control, whereas no sign of the virus was observed in the vehicle and the negative control groups. The histologic changes in the experimental group were significantly less than the positive control group. Also, the Blood-brain barrier impermeability was significantly decreased in the other groups compared to the positive control group. Although more studies are needed to verify the exact mechanisms of pretreatment potential effects of omy-miR-731 Antagomir, the present results proved that pretreatment potential of omy-miR-731 Antagomir can protect the brain tissue against signs of VHS and preferably would be a new approach against VHSV infection in rainbow trout.

The effect of different fatty acids in close–up period on population and size of follicles and blood parameters related to the energy state of the body after calving of lactating dairy cows was measured. In this study 12 Holstein cows were selected by expected date of parturition (around 30 days before calving) and assigned them randomly within one of the three experimental treatments including: 1) control (with carbohydrate source)، 2) Rumen-protected fat (RF) and 3) Roasted Soybean (RS). The diets were formulated to be isonitrogenous and not iso-caloric. Blood samples were collected at 7 day intervals in -21، -14، -7، 1، 7، 14، 21 periods of calving. Also dry matter intake and body condition score cows were recorded. Ovarian activity was monitored by daily transrectal ultrasound scanning from 30 to 40 and 60 to 70 DIM. In blood parameters section only glucose concentrate، significantly was different among treatment groups and the value of glucose in RS group was higher than RF group. Reproductive activity in cows that were fed RS group was higher than RF group. Differences in dry matter intake and body condition score were not significant.