عنوان مقاله [English]
The effects of antibiotics and oxygen on the fertilizing capacity of unfertilized ova of (Salmo trutta caspius) during storage were studied in two separate experiments. In the first experiment, egg batches were stored without oxygen. In the second experiment, egg batches were stored in the presence of two concentrations of antibiotics (1: 250IU penicillin+ 250µg streptomycin and 2: 500 IU penicillin+ 500µg streptomycin and3: 750 IU penicillin+ 750µg streptomycin per ml of celomic fluid) and then were transferred to plastic bags with sufficient oxygen content and kept at (2-3C) using domestic refrigerator. The fertilizing assays were carried out at 0 (control), 4, 8, and 12 days post storage. The results of the present study revealed that the fertilizing capacity of stored eggs decreased with the passage of time. In the first experiment there was no significant difference between eggs fertilized after 4 days of storage compared to control (day 0), but after 8 days of storage a significant difference was observed . In the second experiment, the fertilizing capacity of egg batches stored for 4 days without antibiotics showed significant reduction compared to control. The highest fertilizing capacity of hatching was observed in day 0. Unlike concentration 0, other two concentrations (1 and 2) had no significant difference with control and each other. There was little difference in concentration 3 in fertilizing and hatching percentage. The resolute in day 8 of maintenance was similar to day 4. Fertilizing and hatching percentage in day 12 of maintenance with antibiotic 0 concentrations was very low. In spite of this, there was no significant difference in fertilizing percentage between two concentrations of 1 and 2 (77.61, 62.59) respectively with control and observed significant difference in concentration 3 with control. Also, injection of oxygen showed significant positive effects on fertility of eggs (60.44% eyeing rate) compared to egg batches stored without oxygen (7.11%).