African catfish Clarias gariepinus brood stocks were bred by normal induced breeding method, After fertilization, the eggs were treated with 0.40%, 0.50% and 0.60% concentration levels of MS (methylated spirit) and ...African catfish Clarias gariepinus brood stocks were bred by normal induced breeding method, After fertilization, the eggs were treated with 0.40%, 0.50% and 0.60% concentration levels of MS (methylated spirit) and a control treatment without MS (0%). The objective was to remove the stickiness of the egg outer vitelline membrane to improve hatchability and survival of the hatchlings. Two batches of the treatments were carried out according to treatment duration of 5 s and l0 s. The eggs hatched normally with the highest hatching percentage of 62.31% in eggs treated with 0.40% MS concentration in 5 s treatment and 61.92% in the same concentration for 10 s. The control treatment of 0.00% MS treatment gave the lowest hatchability of 49.69% at 5 s and 45.71% at 10 s exposure time. Growth performance of the hatchlings improved in eggs treated than those not treated. Those treated had higher weight gain and percentage specific growth rates than those not treated. Percentage survival ranged from 75% to 90 % in both treated and untreated groups. MS can therefore be safely used in fish hatchery to prevent egg stickiness to improve hatchability and larval development.展开更多
Dear Editor,Infectious bursal disease virus(IBDV)causes infectious bursal disease,a highly contagious immunosuppressive disease that affects young chickens and causes economic losses in the poultry industry worldwid...Dear Editor,Infectious bursal disease virus(IBDV)causes infectious bursal disease,a highly contagious immunosuppressive disease that affects young chickens and causes economic losses in the poultry industry worldwide.IBDV replicates mainly in actively dividing B lymphocytes within the bursa of Fabricius(BF),leading to immunosuppression in affected flocks(Mahgoub et al.,2012).Viral protein 2(VP2),展开更多
文摘African catfish Clarias gariepinus brood stocks were bred by normal induced breeding method, After fertilization, the eggs were treated with 0.40%, 0.50% and 0.60% concentration levels of MS (methylated spirit) and a control treatment without MS (0%). The objective was to remove the stickiness of the egg outer vitelline membrane to improve hatchability and survival of the hatchlings. Two batches of the treatments were carried out according to treatment duration of 5 s and l0 s. The eggs hatched normally with the highest hatching percentage of 62.31% in eggs treated with 0.40% MS concentration in 5 s treatment and 61.92% in the same concentration for 10 s. The control treatment of 0.00% MS treatment gave the lowest hatchability of 49.69% at 5 s and 45.71% at 10 s exposure time. Growth performance of the hatchlings improved in eggs treated than those not treated. Those treated had higher weight gain and percentage specific growth rates than those not treated. Percentage survival ranged from 75% to 90 % in both treated and untreated groups. MS can therefore be safely used in fish hatchery to prevent egg stickiness to improve hatchability and larval development.
基金supported by grants AERG 232141/PNBIO 1131032 from the Instituto Nacional de Tecnología Agropecuaria(INTA)PICT 2008-0400 from the Agencia Nacional de Promoción Científica y Tecnológica(ANPCyT),Argentina
文摘Dear Editor,Infectious bursal disease virus(IBDV)causes infectious bursal disease,a highly contagious immunosuppressive disease that affects young chickens and causes economic losses in the poultry industry worldwide.IBDV replicates mainly in actively dividing B lymphocytes within the bursa of Fabricius(BF),leading to immunosuppression in affected flocks(Mahgoub et al.,2012).Viral protein 2(VP2),