Gross Abnormalities in Tilapia

Tave, Douglas,Jo, Jae-Yoon,Kim, Dong-Soo The Korean Society of Fisheries and Aquatic Scienc 2011 Fisheries and Aquatic Sciences Vol.14 No.2

Thirty-one gross abnormalities that have been observed in tilapia are described: 10 fin, five eye, five jaw, four body shape, three head, two yolk sac, one operculum, and conjoined twins. Twenty-one have been described in published papers; the others were obtained from a survey. Breeding experiments revealed that three were heritable, while six were not heritable. Five could be caused by a bacterial infection, and one could be produced by a fungus. Four deformities were in offspring of males that had been injected with methyl methane sulphonate. Three were produced when sperm was treated with methyl methane sulphonate. Six were observed during sex reversal studies, and one was found following heat shock of fertilized eggs. Three were observed in polluted river water. The cause of other deformities is not known.

Review Article : Gross Abnormalities in Tilapia

( Douglas Tave ),( Jae Yoon Jo ),( Dong Soo Kim ) 한국수산과학회(구 한국수산학회) 2011 Fisheries and Aquatic Sciences Vol.14 No.2

Thirty-one gross abnormalities that have been observed in tilapia are described: 10 fin, five eye, five jaw, four body shape, three head, two yolk sac, one operculum, and conjoined twins. Twenty-one have been described in published papers; the others were obtained from a survey. Breeding experiments revealed that three were heritable, while six were not heritable. Five could be caused by a bacterial infection, and one could be produced by a fungus. Four deformities were in offspring of males that had been injected with methyl methane sulphonate. Three were produced when sperm was treated with methyl methane sulphonate. Six were observed during sex reversal studies, and one was found following heat shock of fertilized eggs. Three were observed in polluted river water. The cause of other deformities is not known.

Original Articles : Effect of High Stocking Rates on Growth and Survival of the Endangered Rio Grande Silvery Minnow Hybognathus amarus

( Alison M. Hutson ),( Louie A. Toya ),( Douglas Tave ) 한국수산과학회(구 한국수산학회) 2013 Fisheries and Aquatic Sciences Vol.16 No.4

The endangered Rio Grande silvery minnow Hybognathus amarus was cultured in 2.44-m-diameter outdoor tanks in a 131-day yield trial to assess growth, survival, and percentage of taggable-sized fish (>35 mm total length) when stocked at 500/tank (1.07million/ha), 1,000/tank (2.14 million/ha), and 1,500/tank (3.21 million/ha). At harvest, fish averaged 45.6 mm and 0.94 g in the 500/tank treatment, 42.6 mm and 0.74 g in the 1,000/tank treatment, and 38.4 mm and 0.55 g in the 1,500/tank treatment; the differences were significant (P = 0.05). Survival in the three treatments was 70%, 64%, and 52%, respectively, but the differences were not significant. Percent taggable-sized fish was 86%, 89%, and 65%, respectively, but the differences were not significant. Yield was 672.5 kg/ha, 1,026.6 kg/ha, and 887.8 kg/ha, respectively; yield in the 1,000/tank treatment was significantly greater than that in the 500/tank treatment, but was not significantly greater than that of the 1,500/tank treatment. This facility is a conservationfacility and a major goal is to raise fish without formulated feed. Fertilization produced good growth for the first month, but little growth occurred during the second month so supplemental feed had to be used for the final 60 d of the yield trial.

Effect of High Stocking Rates on Growth and Survival of the Endangered Rio Grande Silvery Minnow Hybognathus amarus

Hutson, Alison M.,Toya, Louie A.,Tave, Douglas The Korean Society of Fisheries and Aquatic Scienc 2013 Fisheries and Aquatic Sciences Vol.16 No.4

The endangered Rio Grande silvery minnow Hybognathus amarus was cultured in 2.44-m-diameter outdoor tanks in a 131-day yield trial to assess growth, survival, and percentage of taggable-sized fish (${\geq}35mm$ total length) when stocked at 500/tank (1.07 million/ha), 1,000/tank (2.14 million/ha), and 1,500/tank (3.21 million/ha). At harvest, fish averaged 45.6 mm and 0.94 g in the 500/tank treatment, 42.6 mm and 0.74 g in the 1,000/tank treatment, and 38.4 mm and 0.55 g in the 1,500/tank treatment; the differences were significant (P = 0.05). Survival in the three treatments was 70%, 64%, and 52%, respectively, but the differences were not significant. Percent taggable-sized fish was 86%, 89%, and 65%, respectively, but the differences were not significant. Yield was 672.5 kg/ha, 1,026.6 kg/ha, and 887.8 kg/ha, respectively; yield in the 1,000/tank treatment was significantly greater than that in the 500/tank treatment, but was not significantly greater than that of the 1,500/tank treatment. This facility is a conservation facility and a major goal is to raise fish without formulated feed. Fertilization produced good growth for the first month, but little growth occurred during the second month so supplemental feed had to be used for the final 60 d of the yield trial.

청틸라피아의 체조성과 생식소 중량 지수에 미치는 $17\alpha-Methyltestosterone$ 호르몬의 영향

조재윤,알 오닐 스미들먼,더글러스 테이브,Jo Jae-Yoon,Smitherman R. Oneal,Tave Douglas 한국양식학회 1995 韓國養殖學會誌 Vol.8 No.3

청틸라피아 (Oreochromis aureus)의 자어에 0, 1, 10, 60 ppm의 $17\alpha-methyltestosterone$(MT)을 30 일간 사료에 섞어 먹인 후 다음 57 일간을 0 ppm을 먹인 그룹은 다시 세그룹으로 나누어 0 ppm MT (0-0), 10 ppm MT (0-10), 및 60 ppm MT (0-60)을 먹였고, 60 ppm 을 먹인 그룹은 다시 3 그룹으로 나누어 0 ppm MT (60-0), 10 ppm MT (60-10), 및 60 ppm MT (60-60)을 먹였으며, 초기 30 일간 1 ppm과 10 ppm MT를 먹인 것은 계속해서 1과 10 ppm을 먹여서 체조성과 생식소 중량지수에 미치는 영향을 조사하였다. 초기 30 일간 어체의 조단백과 조지방은 MT 농도와 역상관 관계를 보였고, 수분 함량은 순상관 관계를 보였다. 후기 57 일간에 먹인 MT는 초기 30 일간 먹인 MT 보다도 숫컷의 체조성에 더 큰 영향을 미쳤다. 사료 중의 MT는 초기 30 일간이나 후기 57 일간 모두 숫컷의 생식소 중량지수에 나쁜 영향을 보인 반면에, 암컷의 경우에는 후기 57 일간에 사료 중의 MT 양이 생식소 중량지수에 나쁜 영향을 나타내었다. Blue tilapia, Oreochromis aureus swim-up fry were fed,0, 1, 10, or 60 ppm $17\alpha-methyltestosterone$(MT) for 30 days (sex reversal period). Fish that had been fed 0 ppm MT during the sex reversal period were subsequently fed 0 ppm MT (0-0), 10 ppm MT (0-10) or 60 ppm MT (0-60) for the next 57 days (post sex reversal period) ; fish that had been fed 60 ppm MT during the sex reversal period were subsequently fed 0 ppm MT (60-0), 10 ppm MT (60-10), or 60 ppm MT (60-60) during the post sex reversal period. One group was fed 1 ppm MT (1-1), while another group was fed 10 ppm MT (10-10) during the entire 87-day experiment. There was a significant inverse relationship between concentration of MT and percentage body protein and percentage body fat at the end of the sex reversal period, while there was a significant positive relationship between concentration of MT and percentage body moisture. MT treatment during the post sex reversal period had greater effects on body composition of males at the end of the post sex reversal period than did MT treatment during the sex reversal period. There was a significant inverse relationship between MT concentrations, during both the sex reversal and post sex reversal periods, and gonosomatic indices (GSI) in males. In females, there was a significant inverse relationship between MT concentrations during the post sex reversal period and GSI.

청틸라피아의 2년째 성장, 체조성 및 생식소 중량 지수에 미치는 $17\alpha-Methyltestosterone$의 잔류 효과

조재윤,알 오닐 스미들먼,더글러스 테이브,Jo Jae-Yoon,Smitherman R. Oneal,Tave Douglas 한국양식학회 1995 韓國養殖學會誌 Vol.8 No.4

청틸라피아(Oreochromis aureus)의 자어에 0, 1, 10, 60 ppm의 $17\alpha-Methyltestosterone$ (MT)을 30 일간 성 전환기 사료에 섞어 먹인 후 다음 39 일간(성전환 후기) 0 ppm 을 먹인 그룹은 다시 세 그룹으로 나누어 0 ppm MT (0-0), 10 ppm MT (0-10), 및 60 ppm MT (0-60)을 먹였고, 60 ppm을 먹인 그룹은 다시 3 그룹으로 나누어 0 ppm MT (60-0), 10 ppm MT (60-10), 및 60 ppm MT (60-60)을 먹였으며, 초기 30 일간 1 ppm과 10 ppm MT를 먹인 것은 계속해서 각각 1 ppm과 10ppm을 먹여서 월동시킨 다음 10개월 후인 이듬해 9월 말경에 체조성과 생식소 중량 지수에 미치는 영향을 조사하였다. 암수 모두에서 2 년째의 성장에 대한 MT의 잔류 효과는 없었다. MT를 먹인 그룹의 성장은 전혀 먹이지 않은 대조군보다 통계적으로 유의성있게 좋았는데(P<0.05) 그 이유는 대조군에 있는 암컷의 성장 지연으로 인한 전체 평균 중량의 감소 때문이었다 사료 중의 MT 함량이 증가하는데 따라 수컷의 조지방 함량은 증가하여 순상관 관계의 잔류 효과를 나타내었으나 체 수분 함량은 오히려 MT가 증가함에 따라 감소하는 역상관 관계의 결과가 나타났다. 암컷에서는 사료 중 MT가 증가함에 따라 체 수분함량이 감소하는 역상관 관계의 잔류 효과를 보였다. 성전환 후기의 암수 모두의 생식소 중량 지수에 역상관 관계를 나타내었고, 성전환기에 사료에 섞어 섭취된 MT는 2 년째의 수컷의 생식소 중량 지수에 잔류 효과를 나타내어 MT 농도가 증가하는데 따라 생식소 중량 지수가 감소하는 역상관 관계를 나타내었다. .그러나 생식소 발달이 완료된 성전환 후기에 먹인 MT는 암수 모두에서 생식소 중량 지수에 잔류 영향을 보이지 않았다. Blue tilapia, Oreochromis aureus (Steindachner) swim-up fry were fed a ration containing 0, 1, 10, or 60 ppm $17\alpha-Methyltestosterone$ (MT) for 30 days (sex reversal period). Fish that had been fed 0 ppm MT-treated feed during the sex reversal period were subsequently fed rations containing either 0 ppm MT, 10 ppm MT, or 60 ppm MT for the next 39 days (post sex reversal period) : fish that had been fed 60 ppm MT-treated feed during the sex reversal period were subsequently fed rations containing either 0 ppm MT, 10 ppm MT, or 60 ppm MT during the post sex reversal period. One group was fed 1 ppm MT-treated feed, while another group was fed 10 ppm MT-treated feed during both periods. The following growing season (10 months later), the residual effects of MT on weight gain, body composition, and gonosomatic indices (GSI) were evaluated. MT had no residual effect on growth of either sex. Groups that ate MT-treated feed were significantly (P<0.05) larger than those that received no MT during the sex reversal period, because females in the latter group lowered average weight gain. MT had a positive residual effect on body fat content in males, but had a negative effect on body moisture content. MT had a positive residual effect on body moisture content in females. MT had a significant negative effect on male and female GSI at the end of the post sex reversal period. MT consumption during the sex reversal period had a significant negative residual effect on male GSI. MT fed after sexual development (post sex reversal period) did not have a residual effect on male or female CSI.

나일틸라피아와 청틸라피아의 성전환과 초기 성장에 미치는 $17\alpha-Methyltestosterone$ 호르몬의 영향

조재윤,알 오닐 스미들먼,더글러스 테이브,Jo Jae-Yoon,Smitherman R. Oneal,Tave Douglas 한국양식학회 1995 韓國養殖學會誌 Vol.8 No.2

여섯 가지 농도(0, 5, 10, 15, 20, 30 ppm)의 $17\alpha-Methyltestosterone$ (MT)를 사료에 섞어서 청틸라피아 (Oreochromis aureus)와 나일틸라피아 (O. niloticus)에 30일간 먹여서 성전환율과 성장을 비교한 결과는 다음과 같다. 두 종류 모두 15 pprn의 MT는 $100\%$ 숫컷이 생산되었다. MT를 먹인 것이나 먹이지 않은 나일틸라피아는 청틸라피아보다 빨리 성장하였다(P<0.05) The effects of six levels (0, 5, 10, 15, 20, and 25 ppm) of dietary $17\alpha-Methyltestosterone$ (MT) on sex reversal and growth of Oreochromis aureus (Steindachner) and O. niloticus (L.) were evaluated. Fifteen ppm MT produced $100\%$ male populations in both species. Both MT-treated and untreated O. niloticus grew significantly faster than their O. aureus counterparts (P<0.05).

Effects of Dietary 17α-Methyltestosterone on Body Composition and Gonosomatic Indices in Blue Tilapia, Oreochromis aureus (Steindachner)

조재윤(Jae-Yoon Jo),알 오닐 스미들먼(R. Oneal Smitherman),더글러스 테이브(Douglas Tave) 한국수산과학회 양식분과 1995 韓國養殖學會誌 Vol.8 No.3

Effects of Six Levels of Dietary 17α-Methyltestosterone on Sex Reversal and Growth of Oreochromis aureus (Steindachner) and O. niloticus (Linnaeus)

조재윤(Jae-Yoon Jo),알 오닐 스미들먼(R. Oneal Smitherman),더글러스 테이브(Douglas Tave) 한국수산과학회 양식분과 1995 韓國養殖學會誌 Vol.8 No.2

Residual Effects of Dietary 17α-Methyltestosterone on Second-Year Growth, Body Composition, and Gonosomatic Indices of Blue Tilapia, Oreochromis aureus (Steindachner)

조재윤(Jae-Yoon Jo),알 오닐 스미들먼(R. Oneal Smitherman),더글러스 테이브(Douglas Tave) 한국수산과학회 양식분과 1995 韓國養殖學會誌 Vol.8 No.4