The Snakeheads are the most common fishes in freshwater wetlands of Bangladesh, but in recent years they are subjected to decline by overfishing pressure, anthropogenic factors, and climate changes. A one-year-long biometric investigation was undertaken which involve monthly random sampling of Channa striata and Channa punctatus from local wetland waters and measured total length, body weight data, and gonad’s weight in the laboratory. Then data were treated and analyzed by following the different multi-model tools i.e., Fulton’s condition factor, relative condition factor, allometric condition factor, and Pearson’s correlation coefficient. The results exhibit a strong correlation between the total length and body weight of Channa striata and Channa punctatus with an r2 value of 0.826, 0.819, respectively. Pearson’s correlation showed a trend of both positive and negative correlation coefficients between different conditions factors and morphometry for both species. The peak value for gonad’s weight, gonadosomatic index, and Dobriyal index was reported in the monsoon while the bottom value was in winter for both sexes of both species. The temperature, dissolved O2, and turbidity were found as fluctuating throughout the season while dissolved NH3 and pH remained constant. This data will help in the betterment of conservation, management, and fishing policy by the government, scientists, and fisheries industry.
|
The nutritional value of stuffed meatballs made with minced rainbow trout rather than red meat in the stuffing was investigated, as well as color variations (L *, a *, and b *) and sensory quality, using two different cooking methods (boiling and frying) on samples stored in the freezer (-18 oC). As a result of this research, the moisture, the crude ash, the lipid, and the crude protein contents of stuffed meatballs produced with rainbow trout were found as %58.25 ± 0.93, %2.01 ± 0.05, %5.28 ± 0.29, and %7.69± 0.08, respectively. The content of total saturated fatty acids composition (∑SFA), total monounsaturated fatty acids composition (∑MUFA), and total polyunsaturated fatty acids composition (∑PUFA) was found to be 12.52 ± 0.23%, 39.11 ± 1.27%, and 43.73 ± 1.98%, respectively. The atherogenic (AI) and thrombogenic indexes (TI) for dietary factors associated with cardiovascular disease were found to be 0.10 and 0.25, respectively. In the evaluation of color (L *, a *, and b *) of frozen samples, L * (black-white) and b * (blue-yellow) values in all groups (raw, boiled, and fried) increased significantly at the end of storage compared to the initial value ( p<0.05). Following frying and boiling, the * (green-red) values of the frozen-stored samples decreased significantly (p<0,05). Sensory quality was assessed in this study using two cooking methods: boiling and fried, both of which are common serving methods for stuffed meatballs. Although a significant decrease was detected in all sensory quality parameters of samples during frozen storage, it was determined that it did not reach the unacceptable limit at the end of storage.
|
Two specimens of Argyropelecus gigas and Conocara fiolenti were collected from off the city of Salalah on the Arabian Sea coasts of Oman. The specimens represent the first confirmed record of the species from the northwestern quadrat of the Indian Ocean. Meristic and morphometric characters match those described for these species.
|
Cıva yeryüzündeki en toksik ağır metallerden biridir. Selenyum canlılar için gerekli olan ve antioksidan özellikleri de bulunan bir elementtir. Zeolit ise sucul ortamlarda ağır metallerin uzaklaştırılmasında yaygın bir şekilde kullanılan bir mineraldir. Bu araştırmada Oreochromis niloticus’un dokularındaki glutatyon (GSH) ve GSH ile ilişkili enzim sistemleri üzerine cıvanın toksik etkileri ve bu biyokimyasal toksisite üzerine selenyumun ve zeolitin olası koruyucu etkilerinin belirlenmesi amaçlanmıştır. Bu amaçla balıklar 0,01 ve 0,1 mg/L cıva; 0,01 mg/L cıva+0,1 mg/L selenyum, 0,1 mg/L cıva+1,0 mg/L selenyum ve 0,01 mg/L cıva+ 0,1 g/L zeolit, 0,1 mg/L cıva+1,0 g/L zeolit derişimlerinin etkisine 7 ve 21 gün süreler ile bırakılmış ve solungaç, karaciğer ve kas dokularındaki GSH düzeyi ve glutatyon peroksidaz (GPx), glutatyon-S-transferaz (GST) ve glutatyon redüktaz (GR) enzim aktiviteleri belirlenmiştir. Cıvanın tek başına ve cıva+selenyum ve cıva+zeolit karşımlarının etkisinde incelenen tüm biyokimyasal parametrelerde dokulara, ortam derişimlerine ve etki süresine bağlı olarak önemli değişimler saptanmıştır. Solungaç ve karaciğerde GSH düzeyi ve GR aktivitesi azalma, GPx ve GST aktiviteleri ise artış göstermiştir. Kasta ise GST dışındaki parametrelerde önemli bir değişim gözlenmemiştir. İncelenen tüm parametreler üzerine tek başına cıva etkisinin selenyum ve zeolit ile birlikte etkisine göre daha yüksek ve kimyasalların etkilerinin genel olarak Hg>Hg+Zeolit>Hg+Se şeklinde olduğu saptanmıştır. Araştırma sonuçlarımız O. niloticus’ta cıvanın neden olduğu toksisite üzerine selenyum ve zeolitin koruyucu bir etkiye sahip ve selenyumun zeolite oranla koruyuculuk etkisinin biraz daha fazla olduğunu göstermektedir.
|
The high of catching intensity or overfishing of dusky whaler shark, Carcharhinus obscurus (Lesueur, 1818), has threatened its sustainability. Even though fisheries and biological aspects of C. obscurus are important as a basic assessment for making regulation of shark fisheries management. However, those studies never been reported in Indonesia. The aim of this study is to identify the number of catches and biological aspects of C. obscurus. This study was conducted from January to March 2018 at Fishery Port Technical Implementation Unit (FP-TIU) Muncar, Banyuwangi, Indonesia. 54 C. obscurus individuals were obtained using random sampling survey method. Here, we found that the number of C. obscurus landed in 2018 was higher compared to 2014 and 2017. The shark length ranged from 172 to 394 cm. Percentages of male and female adults of C. obscurus were 22.22 and 46.30%, respectively. Whilst in the juveniles were 20.37% males and 11.11% females. The maturity rate based on clasper length, male landed sharks was 82.61% classified within full calcification and 17.39% non-full calcification level. The sex ratio of C. obscurus sharks that are landed was 1:1.34 (M: F).
|
During the research in the grand port area of Antalya (coordinates: 36. 829022N; 30. 603739 E), it was observed that a very rare fish belonging to the Trachipteridae family was stranded in the Mediterranean Sea. The length of the fish, which weighs 400 g (TW = 400g), has been measured as 85cm (TL = 85cm). The fish without anal fin has a dorsal fin with red colour and soft rays, extending from the dorsal to the caudal region. In the examination made; it has been understood that this fish is Ribbon fish, Trachipterus trachypterus (Gmelin, 1789) which are rare fish in the Mediterranean Sea. In a review of previous studies, it was previously understood that this species was not given in the Gulf of Antalya. In the study, the Ribbon fish, Trachipterus trachypterus (Gmelin, 1789), is presented as a new record in the Gulf of Antalya (Turkey).
|
A seventy-five-day feeding study was performed to investigate the usage of black soldier fly (Hermetia illucens) larvae meal as an alternative protein source in carp diets (Cyprinus carpio). In this study, experimental fish were fed with four different diets (fish meal-based without Black soldier fly larvae (BSFL) meal (BSFL0), 50% (BSFL50), 65% (BSFL65), and 75% (BSFL75) of fish meal substitution with BSFL), with triplicate. The carps (1.045±0.083 g) were randomly stocked into twelve flow-through tanks with a density of 50 fish per tank and reared for 75 days. Diet feed was provided to carps as a proportion of their biomass (5% of their mass per day) with two meals a day. Carps fed with BSFL65 meal showed positive effects on weight gain (WG), specific growth rate (SGR), protein efficiency ratio (PER), apparent net protein utilization (ANPU), and feed conversion ratio (FCR). There were significant differences in moisture, crude protein, lipid, and ash content in the whole body among dietary groups (P<0.05). The protein content of the carp-fed BSFL75 diet group (20.22%) was significantly the highest among all three diet groups. Consequently, a BSFL meal can be considered as an alternative animal source of protein for the carp diet.
|
Examination of 341 individuals of Luciobarbus callensis caught in Foum El Khanga Dam during the year 2015, allowed us to collect 2782 specimens of the parasitic species Dactylogyrus heteromorphus El Gharbi, 1994. The statistical study of the epidemiological index distribution of D. heteromorphus shows that the parasitic infestation varies from one season to another. In contrast, the sex and size of L. callensis do not affect parasite infestation. Variations in the epidemiological index of D. heteromorphus concerning fifteen physicochemical water parameters were tested statistically. These variations are significant with temperature, salinity, nitrate, nitrite, chloride, phosphate, calcium, sulfate, hardness, turbidity, and electrical conductivity, however, no significant effect of the concentration of magnesium, dissolved oxygen, ammonium, and pH on these indexes according to the Pearson’s parametric test.
|
Water management is considered to be a field that searches for optimal solutions to the problems posed by society's need for water and the availability of water in nature. Urbanization and rapid increase in population have brought many problems related to water resources, especially in developing countries like Ethiopia. As a result, millions of people do not have access to potable water and improved sanitation. This study found that the main water problems in Ethiopia are more likely to result from weaknesses in coordination, lack of adequate authorized institutions, rapid population growth, technical, financial, and hydro political problems rather than water scarcity. The country's policy on sharing its natural resources, allocation, and management of transboundary water resources creates major problems between upstream and downstream countries. The study recommends advanced management mechanisms and appropriate approaches that can solve the existing problems and promote the socio-economic development of the country.
|
Bu çalışma 2017 yılında Oymapınar Baraj Gölü’nde yürütülmüştür. Çalışma kapsamında göl suyunda, sedimentinde ve gölde yaşayan sazanın (Cyprinus carpio L.,1758) kas, karaciğer ve solungaç dokularındaki bazı ağır metallerin konsantrasyonlarının belirlenmesi amaçlanmıştır. Göl suyunda Mo (<0.0008) her mevsim, Cu (<0.0006) ilkbahar ve sonbahar mevsimlerinde analiz limitinin altında kalmıştır. Suda en fazla biriken metal Fe, en az biriken metaller ise Cd ve Cr olmuştur. Mevsimsel olarak yapılan değerlendirmede Cd, Cu, Mn, Ni ve Se’un sonbahar mevsiminde, Cu, Fe ve Zn’nun kış mevsiminde ve Pb’un yaz mevsiminde artış gösterdiği tespit edilmiştir. Buna karşın Cd, Cu, Fe, Mn ve Zn’nun yaz mevsiminde, Cr, Ni ve Se’un ilkbahar mevsiminde ve Pb’un kış mevsiminde azaldığı saptanmıştır. Göl sedimentinde tüm metaller her mevsimde belirlenmiştir. Sedimentte de en fazla biriken metal Fe, en az biriken metal ise Cd olmuştur. Mevsimsel olarak yapılan değerlendirmede Mo (sonbahar mevsiminde) hariç tüm metallerin miktarlarının yaz mevsiminde arttığı belirlenmiştir. Buna karşın Cu, Mn, Ni, Cr, Fe, ve Zn’ nun ilkbahar mevsiminde, Cd ve Pb’nun sonbahar mevsiminde, Se’un kış mevsiminde ve Mo’in yaz mevsiminde azaldığı belirlenmiştir. Balıklarda analizi yapılan tüm metaller her mevsimde her dokuda belirlenmiştir. Elde edilen sonuçlar genellendiğinde metallerin kasta kış mevsiminde, karaciğerde ilkbaharda ve solungaçta yaz mevsiminde arttığı, kasta ilkbaharda ve solungaçta ise sonbaharda azaldığı saptanmıştır. Karaciğerdeki metal azalışı mevsimsel olarak birbirine benzerlik göstermektedir. Su ve balık dokularında belirlenen değerler, Çevre ve Şehircilik Bakanlığı, EPA, WHO, EU, EC, TGK ve FAO’nun verdiği ağır metallerin kabul edilebilir sınırları ve su kalite sınıfı değerleri ile kıyaslanmıştır. Sedimentte belirlenen konsantrasyonlar sediment kalite kriterlerine göre değerlendirilmiştir.
|
