Effect of Probiotics on Reproductive Performance of Fish

Probiotics are defined as live microorganisms which when administered in adequate amounts, confer a health benefit on the host. Nowadays, Probiotics are used for eco-friendly and sustainable production in many production areas. They have also been common organisms that used in aquaculture as growth promoter, stress tolerance, pathogen inhibition, and nutrient digestibility, to increase water quality. Probiotics use in aquaculture comprehensively reviewed as an alternative to antibiotic treatment. However, very few studies have addressed the effects of probiotics on reproductive performance and gamete quality of fish. Thus, this review summarizes most current studies on the effects of probiotics on reproductive performance and gamete quality in fish and evaluates further applications of probiotics in reproduction of fish

Isolation, culture and bacterial contamination of oogonial stem cells of Brown trout, Salmo <i>trutta macrostigma</i> (Dumeril, 1858)

530-538Increased commercial value of brown trout, Salmo trutta macrostigma has lead to its declined natural stock due to over exploitation, and thereby made it an endangered species. Cryopreservation of spermatogonial and oogonial stem cells may help in protecting this species. In this context, we have earlier isolated and cultured spermatogonial stem cells from male S.t. macrostigma. In this study, we report isolation and culture of oogonial stem cells from brown trout (S. t. macrostigma).In addition, bacterial contamination in oogonial cell culture media were identified and described. Wild females wereobtained from Kılıç Trout Fish Farm (Kahramanmaraş, Turkey). In order to identify the appropriate size, age and ovarystructure for oogonial stem cell isolation and culture, the ovary structure was morphologically and histologically studied.Fish were anesthetized with 0.04% 2-phenoxethanol. The ovary tissue were digested by 0.25% trypsin-EDTA.HBSS, with1.0 μg/mL NaHCO3, antibiotics were used to maintain cells in a viable stage. The concentration of cells was measured byhemocytometer. Antibiogram and Gram staining techniques were applied to the culture media contaminated with bacteria.Appropriate age, size and weight of trout for oogonial stem cell isolation and culture were identified as 7+ month old,14.6±1.6 cm, 28.2±7.7 g, respectively. The highest oogonial stem cells were measured in the perinucleolar stage of theovary. Enterobacter cloacae and Acinetobacter baumannii were identified in the contaminated cell media. Density ofoogonial stem cells were measured as 5.4×105±2.6×105 cells/mL. In this study, germ cell isolation and culture technique wasdeveloped for S. t. macrostigma

Sosyal etkenler, Lhrh-A ve pimozide'nin çipura (Sparus Aurata)'da cinsiyet değişimi ve steroid hormonları üzerine etkileri

TEZ3802Tez (Doktora) -- Çukurova Üniversitesi, Adana, 2002.Kaynakça (s. 94-111) var.v, 111 s. ; 30 cm.

The effets of combined phytoestrogen administration on growth performance, sex differentiation and body composition of sharptooth catfish Clarias gariepinus (Burchell, 1822)

The present study was conducted to investigate the effects of Genesis (G, a commercial mixture of phytoestrogens) on growth, body composition and sex differentiation of Sharptooth catfish Clarias gariepinus. Genesis is a commercially available product on USA and European markets used for menopausal complaints as an alternative medicine. Different concentrations (0 mg G 30 L-1, 210 mg G 30 L-1, 420 mg G 30 L-1, 630 mg G 30 L-1, 750 mg G 30 L-1 and 1500 mg G 30 L-1) of Genesis were administered by immersion of newly hatched larvae (averaging 2.27&plusmn;0.12 mg) every 3 days for 30 days then immersion treatments were ceased and all groups reared in the same condition for the later 90 days, a total 120 days experimental period. At the end of the trial, specific growth rate of the females increased with the increasing concentration of Genesis up to 420 mg 30 L-1 (P&lt;0.05), but different concentrations of Genesis did not affect the growth performance of males (P&gt;0.05). The highest value of protein content (21.60%) was observed from the 420 mg G 30 L-1 group and found significantly different from the control and other groups (P&lt;0.05). Also, lipid contents were significantly affected by the Genesis concentrations and the highest lipid contents were detected in the 210 mg G 30 L-1 (5.98%) and the 630 mg G 30 L-1 (6.66%) groups. Although among the dosages used in the present study, 1500 mg G 30 L-1 was the most effective dosage that ensured maximum female ratio (69.77%), the sex ratios observed for 0, 210, and 420 mg G 30 L-1 treatment groups were nearly the expected ratio of 1:1 (male: female). Therefore, it was concluded that usage of higher doses and treatment durations of Genesis could be more effective for all-female production of the Sharptooth catfish population

Doğal ve sentetik steroidlerin gökkuşağı alabalığında, oncorhynchus mykiss (Walbaum) gonadal gelişim, cinsiyet dönüşümü ve büyüme üzerine etkileri

Tamamı dişi salmonid stokların üretiminde sentetik cinsiyet hormonlarının kullanımına dayanan erkekleştirme uygulamaları gibi dolaylı yöntemler yaygın bir şekilde kullanılmaktadır. Ancak söz konusu sentetik hormonların toksik etkiler ve yüksek maliyetler gibi dezavantajları bulunmaktadır. Bu bakımdan mevcut araştırmada, doğal steroidlerin kullanımı yolu ile tamamı dişi alabalık populasyonlarının üretimi için dolaylı yöntemlerin geliştirilmesi amaçlanmıştır. Bu çalışmada 7000 prelarval gökkuşağı alabalığı yedi tanka eşit olarak bölünmüş ve bunlar sentetik hormonlar (3 ve 6 mg metiltestosteron -MT ve testosteron -T kg-1yem) ve doğal hormonlar (50 ve 100 mg Tribulus terrestris -TT kg-1) içeren ticari alabalık yavru yemleri (Skretting, France) ile keseli dönemden sonraki 90 gün boyunca beslenmiştir. 90 günlük ilk besleme periyodunun sonunda balıklar cinsiyetlerin makroskopik ve histolojik yöntemlerle belirlenebildiği döneme kadar hormon içermeyen ticari alabalık yemi ile beslenmiştir. Araştırma sonunda 50 ve100 mg/ kg Tribulus terrestris (TT) içeren yemle beslenen balıkların sıra ile %55 ve 63’ü erkek iken, 3 ve 6 mg/ kg testosteron (T) içeren yemle beslenen balıkların sıra ile %51 ve 53 oranında erkek olduğu bulunmuştur. Bu durum Tribulus terrestris’in testosterona göre alabalıkların doğrudan erkekleştirilmesinde daha etkin olduğunu fakat gruplar arasında fark bulunmamıştır. Ayrıca bu araştırma, Tribulus terrestris içeren (100 mg/kg mg/ kg yemde) yemlerle beslenen alabalıkların diğer deneme gruplarındaki balıklara kıyasla daha yüksek canlı ağırlığa ulaştığını bildiren ilk çalışmadır. Kontrol ve deneme grupları arasında farklılaşmamış gonad yapıları bakımından önemli bir farklılık gözlenmemiştir. Sonuç olarak araştırmada, daha yüksek cinsiyet dönüşüm ve büyüme oranlarına ulaşmak için Tribulus terrestris’in daha yüksek konsantrasyonlarının (150, 200, 250 mg kg-1) etkilerini araştırılmalıdır. Ayrıca bu konsantrasyonların gökkuşağı alabalığında, diğer salmonid ve ticari türlerde kan testosteron seviyelerinin yanısıra gonad yapısına olan etkileri de belirlenmelidir.Indirect methods such as masculinizing treatments by synthetic sex steroids has widely been used to produce all-female stocks in salmonids, but they have some disadvantage such as toxicity and high cost. Therefore, the main objective of this research was to develop indirect methods for the production of allfemale populations of Oncorhynchus mykiss through the use of natural steroids.In this study seven thousand prelarval rainbow trout were divided evenly among seven tanks and fed a commercial starter trout diet supplemented with synthetic (3, 6 mg testosterone and methyltestosterone kg-1 diet) and natural steroids (50 and 100 mg Tribulus terrestris kg-1 diet) during 90 days after hatching. Fish were then further reared on a commercial trout diet until sex ratios could be determined through histological and macroscopic observations. The Tribulus terrestris (50 and100 mg/ kg) treatments yielded 55–63% males, while the testosterone (3 and 6 mg/ kg) treatment yielded 51–53% male population. This demonstrates that Tribulus terrestris was effective in the direct masculinization of rainbow trout compared to testosterone, but no significant difference was observed between groups. Also, this study was the first attempt that yielding higher growth of Oncorhynchus mykiss fed with diets containing TT (100 mg kg-1 diet) compared to other experimental groups. There were no marked differences in the structure of the undifferentiated gonads between the control group and all treatment groups. In conclusion, the effects of higher concentrations (150, 200, 250 mg kg-1) of TT should be investigated to reach the higher sex reversal and growth rates, and also determined the blood testosterone levels, gonadal structure of rainbow trout and/or other salmonids, and cultivable fish species

Standart laboratuvar koşullarında yetiştirilen karabalıkların (Clarias gariepinus Burchell, 1822) gonad gelişimi ve cinsiyet oranı

Mevcut çalışmada laboratuvar koşullarında yetiştirilen karabalıkların gonad gelişimleri yumurtadan çıktıktan sonra 365 gün boyunca histolojik ve morfolojik olarak incelenmiştir. Hem erkek hem de dişiler için yumurtadan çıktıktan sonraki 295. günde eşeysel olgunluğa ulaştığı belirlenmiştir. Testislerin oluşumunda 5, ovaryumların oluşumunda ise 6 gelişim aşaması saptanmıştır. Ovaryum gelişim paterni grup senkronize olarak kategorize edilmiştir. Deneme süresince örneklenen 200 balık için cinsiyet oranları 90 erkek ve 110 dişi olarak belirlenmiş olup, bu farklılık önemli bulunmamıştır (P > 0,05). Ayrıca erkeklerin ortalama canlı ağırlıklarının dişilerinkinden daha yüksek olduğu tespit edilmiştir (P < 0,05). Vitellogenezin başlangıcı Nisan ayında kaydedilmiş ve ovaryum gelişimi Temmuzda pik yapmıştır. Bu sonuçlar, bir yaşındaki erkek ve dişi C. gariepinus'un standart laboratuvar koşullarında yavru elde etmek amacıyla kullanılabileceğini önermektedir.In the present work, gonad development and sex ratio of sharptooth catfish (Clarias gariepinus) cultured under laboratory conditions over 365 days from hatching were investigated histologically and morphologically. The maturation stage for both males and females was detected 295 days after hatching. Five and 6 developmental stages were indicated for testis and ovaries,respectively. The developmental pattern of ovaries was categorised as the group-synchronous type. The sex ratio of the 200 sampled fish was 90:110 (male:female) and this difference was not significant (P &gt; 0.05). Additionally, final live mean weight of the males was higher than that of the females (P &lt; 0.05). The beginning of vitellogenesis was in April and ovarian development peaked in July. These results suggest that 1 -year-old male and female C. gariepinus can be used as brood stock for seed production under standard laboratory conditions

The effect of varying dietary energy on gonad development at first sexual maturity of the Sharptooth catfish (Clarias gariepinus Burchell, 1822)

The objective of this study was to investigate the effects of five isonitrogenous (35% crude protein) diets having different energy contents; 10.85, 11.82, 12.73, 13.69, and 15.06 MJ DE/kg, respectively, on the gonad development and weight gain of Sharptooth catfish fingerlings. Energy contents of the experimental diets were increased with the increasing amount of soy-acid oil (0, 4, 8.5, 13, 18%) and each group of fish was fed on their respective diets (group I was fed diet I) during 180 days. The gonad maturation was significantly affected by dietary energy. In both sexes, the histological inspections of the gonads did reveal differences among the fish fed different energetic diets. Fish fed diets I, II, and III had significantly heavier and more developed gonads compared to those on diets IV and V. Fish fed the higher energetic diets (IV and V) had partially low numbers of yolky oocytes compared to other groups. The mean GSI values of female and male fish fed with diet III was significantly greater than those fed diets with higher dietary energy; however, higher HSI values were recorded for fish fed with the higher energetic diets (IV and V). Also, the best weight gain for both males and females were recorded from the fish fed diet III (12.73 MJ DE/kg). Therefore, on the basis of the present results, among energy levels tested, 12.73 MJ DE/kg was found to be optimal for healthy gonad development and weight gain

The effects of sex steroids of endocrine disrupting chemicals on fishes

İnsanların kullanımları sonucunda oluşan ve endokrin sistemi bozan kimyasallar (EBk), omurgalılarda iç kaynaklı hormonların etkilerine benzer etkilerde bulunmakta ve endokrin sistemle karşılıklı etkileşime girebilmektedirler. EBk evsel atıkların karıştığı sularda, endüstriyel atıklarda ve çiftlik hayvanları yem artıklarında saptanmıştır. Bu atıklarla kirlenmiş olan sularda yaşayan balıkların üreme sistemlerinde bozukluklar olduğu görülmüştür. EBk’ın zararlı etkiler; ayrıca kurbağalarda, sürüngenlerde, kuşlarda, memelilerde ve insanlarda da kaydedilmiştir. Doğal östrojen 17?-östradiol (E2), balıkların karaciğerini, vitellogenin (Vtg) sentezlemesi için uyarır. Vitellogenin yumurtanın olgunlaşmasını sağlayan proteindir. 17?-ethinylestradiol (EE2), çok güçlü sentetik bir östrojendir ve tüm dünyada doğum kontrol tableti olarak kullanılmaktadır. Balıklarda 17?-ethinylestradiol, E2’ yi taklit ederek kandaki Vtg’in konsantrasyonunu artırır ve erkeklerin dişileşmesine neden olur. 17?-trenbolone (Tb) androjenik bir steroidtir ve büyük başlarda et verimini artırmak amacıyla kullanılmaktadır. Balıklarda Vtg konsantrasyonunu azalmasına neden olduğu ve dişileri erkekleştirdiği görülmüştür. Yakın bir gelecekte, dünyanın her yerinde EBk nedeniyle insanların ve doğal yaşamın üreme sistemlerinde ciddi problemler görülebilecektir.Endocrine disrupting chemicals (EDCs) are anthropogenic compounds that have similar properties as endogenous hormones in vertebrates and they are capable of interfering with the endocrine system. EDCs have been detected in sewage receiving effluents from industries and livestock feedlots. Fish living in the recipients contaminated with these EDCs are reported to have reproductive disabilities. The deleterious effects of EDCs have also been reported in amphibians, reptiles, aves, mammals and humans. The natural estrogen, 17&amp;#946;-estradiol (E2), stimulates the fish liver to synthesize vitellogenin (Vtg). Vtg is the protein that nourishes the maturation of eggs. 17&amp;#945;-ethinylestradiol (EE2) is a potent, synthetic estrogen used in oral contraceptive preparations. It mimics E2 leading to enhanced circulatory Vtg concentrations and male to female sex reversal in fish. 17&amp;#946;-trenbolone (Tb), an androgenic steroid, is used as growth promoter in beef cattle. It has been reported to cause declined Vtg concentrations and masculinization in fish. In the near future, many serious problems can be seen in human and wildlife reproduction systems because of EDCs