PENGARUH KEPADATAN TERHADAP KINERJA RESIRKULASI

Faktor-faktor yang membatasi jumlah kepadatan ikan adalah desain sistem resirkulasi dan jenis filter yang digunakan. Desain sistem digunakan untuk membuang sisa-sisa hasil metabolisme secara efektif, selain itu juga memperkaya oksigen terlarut dalam air dengan berbagai metode yang ada. Sedangkan jenis filter berfungsi untuk mengurangi dan menghilangkan bahan-bahan yang berbahaya bagi ikan. Jenis filter yang digunakan disesuaikan dengan kebutuhan.Partikel koloid yang terakumulasi akan menyebabkan terjadinya penyumbatan pada filter mekanik sehingga kemampuan filter untuk memisahkan partikel-partikel tersebut akan semakin menurun, mengganggu debit air dan air dalam filter tersebut akan bersifat anaerobik sehingga proses nitrifikasi tidak terjadi.Pada kepadatan tinggi, buangan metabolit akan semakin meningkat sehingga daya kerja biologis menjadi tidak efisien dan air menjadi beracun. Hal ini desebabkan oleh laju proses nitrifikasi lebih rendah bila dibandingkan dengan laju metabolisme tubuh yang berupa buangan metabolit.

Amonia Dan Nitrit Pada Akuakultur

Amonia merupakan zat buang terlarut hasil metabolisme ikan oleh perombakan protein, baik dari kotora ikan sendiri maupun dari sisa pakan. Sisa pakan biasanya akan membusuk sehingga kadar amonia meningkar.
Secara kimia, amonia terdiri dari dua bentuk yaitu unionzided ammonia UIA/NH3 dan ionized ammonia IA/NH4+. Bila kadar UIA dalam air tinggi maka ikan bias mabuk atau keracunan. Sebaliknya IA kurang daya racunnya.
Nitrit (NO2) merupakan gas beracun bagi ikan. Nitrit merupakan hasil perombakan protein yang merupakan ikutan dari amonia. Pada air kotor karena terlalu banyak ikan biasanya mempunyai kadar nitrit yang tinggi.
Kandungan amonia dan nitrit dapat dikurangi ataupun dihilangkan denga cara penggantian air, pemberian aerasi, penguapan, maupun reaksi kimia dengan oksigen. Reaksi amonia dan nitrit dengan oksigen umumnya terjadi karena dibantu oleh bakteri Nitrosomonas sp. Sehingga menjadi bentuk nitrat (NO3) yang tidak beracun. Bakteri Nitrosomonas sp. Akan berkembang sendiri dan berkumpul dan berkoloni pada dinding bak atau akuarium apabila telah lama digunakan.

Ikan Komet (Hias)

Ikan komet

Spesies : Carassius auratus auratus

Family : Cyprinidae

Ordo : Cypriniformes

Class : Actinopterygii

Ikan komet merupakan salah satu strain dari ikan maskoki. Ikan komet dikembangkan di Amerika sekitar akhir abad ke-19. Nama komet diambil dari nama benda angkasa yaitu komet Helley. Ikan komet memiliki ketahanan tubuh yang lebih baik dibandingkan dengan ikan maskoki. Dengan harga yang murah, ikan komet banyak diminati oleh konsumen ikan hias.

Parameter Kualitas Air Pada Budidaya Ikan Hias

Dalam pembudidayaan ikan hias air tawar, parameter lingkungan yang harus terkontrol dengan baik antara lain :

1. Suhu

Menjaga suhu optimal untuk pertumbuhan merupakan suatu hal yang penting. Ikan akan mengalami kerentanan terhadap penyakit pada suhu yang kurang optimal. Fluktuasi suhu yang terlalu besar akan menyebabkan ikan stress yang dapat mengakibatkan kematian pada ikan. Ssecara umum, suhu yang optimal untuk pembudidayaan ikan hias adalah 25 – 32 ^oC, perubahan suhu yang mendadak sebesar 5^oC dapat menyebabkan ikan stres (Daelami,2001)

2. Oksigen Terlarut

DO ( Dissolved Oksigen ) menjadi faktor kualitas air yang sangat kritis dan akan di pengaruhi oleh suhu air, stocking dan laju pakan serta efektivitas aerasi yang di instalasi pada SRAT. Untuk memperoleh produksi optimal, kandungan oksigen harus dipertahankan diatas 5 ppm. Bila kandungan oksigen tetap sebesar 3 atau 4 ppm dalam jangka waktu yang lama, ikan akan menghentikan makan dan pertumbuhannya (Daelami,2001)

3. Keasaman ( pH )

Sub-optimal pH berakibat buruk pada spesies kultur dan menyebabkan ikan stress, mudah terserang penyakit, produktivitas dan pertumbuhan rendah. Tingkat keasaaman yang baik untuk budidaya ikan hias adalah 5,5 – 9,0.

4. Total Nitogen

Total nitrogen yang utama dalam bentuk amonia yang di hasilkan oleh metabolisme ikan dan ekskresi insang sebagai gas amoniak. Amoniak dapat juga diproduksi dari dekomposisi kotoran organik yang dihasilkan oleh pembusukan bahan organik dari sisa pakan. Amoniak dalam air mempunyai 2 bentuk gas yaitu NH₃ atau ion amonium NH₄⁺. Ammonia adalah racun bagi hewan dan dapat menyebabkan iritasi pada insang dan masalah respirasi.

europe protein's market

The effects of the recent agricultural crisis are still being felt in European protein ingredients markets. Fear of consumer reaction to food products containing animal proteins has led to manufacturers adjusting recipes to substitute animal proteins with plant proteins. Companies are also responding to public concerns over genetically modified organisms (GMOs) such as GM-soya by researching replacement proteins such as wheat and pulse. These changes have resulted in increased industry competition as participants race to provide alternative protein ingredients at reasonable prices. This research evaluates the markets for a full range of animal and plant proteins, including soya, gluten, pulse, milk, egg, fish, meat, gelatine, and single-cell proteins. It examines vital drivers and restraints, tracks trends, and presents accurate forecasts for each sector. By offering a comprehensive view of this field, this study offers your company a detailed guide for the future. Identifying and Utilising Cost-effective Proteins Garner Increased Revenues"Marketing potential cost reductions through the inclusion of specific proteins in food products will give firms a strong competitive advantage in protein ingredients markets," says the study's analyst. Participants are increasingly selecting proteins with various functions that result in overall savings in the production process.Food companies continue to select low-cost, high-quality proteins such as caseinates and whey over less cost-effective food ingredients such as milk powder. "Protein manufacturers whose products have low price-quality ratios will need to invest in new product development to sustain growth," says the author. This analysis provides strategic recommendations to help your firm maximise its market share. Nutritional and Nutraceutical Products Opens New Opportunities"Demand for nutritionally balanced proteins are on the rise," observes the analyst. Diet aids, energy snacks and sport supplements are important drivers for this emerging area. As food companies strive to develop products that contain an abundant source of nutrients, protein manufacturers must develop products with a strong nutritional balance and multifunctional properties. "Meanwhile, functional food and nutraceutical markets within Europe have grown 10 to 20 percent since the mid-1990s," says the analyst. "Offering proteins with nutraceutical properties will play a key role in maintaining an organisation's competitive advantage." This study provides in-depth discussions of food preferences trends enabling users to take advantage of this fast growing market. Agricultural Concerns and Genetically Modified Foods Reshape Industry

insect protein for fish

The company today announced the commencement of a research agreement with Mississippi State University in order to complete the development of its product, as well as conduct taste and quality tests for fish fed with the insect protein.

According to the firm's president Ernest Papadoyianis, Neptune Industries' patent-pending Ento-Protein would be a sustainable source of protein to replace fish meal, which is currently made from rapidly declining ocean species such as anchovies, sardines and menhaden.

Neptune Industries said its product, which is expected to be on the market within the next year, will initially target organic and natural fish production before moving into the mainstream seafood market.

Fears about reduced global fish stocks have escalated in recent years. A report published last year in the Science journal claimed that all seafood stocks around the world may collapse by 2050 if fishing continues at its current rate.

The collapse, which would see more than 90 per cent of all wild seafood that is currently fished disappear, would destroy both ecosystems and fishing economies. The findings pile intense pressure on industry and governments to create a more sustainable production chain.

Neptune Industries believes its product comes at a crucial time to help address the issue.

The firm will be working with three divisions of Mississippi State University: the etymology department, to identify insect species most suited for the production of Ento-Protein; the aquaculture department, which will conduct feeding and growth rate tests on fish fed with the new protein; and the food science department, which will conduct taste tests to identify any differences in the taste or quality of fish reared on the new diet.

Once all tests have been completed successfully, the firm will move ahead with the construction of full-scale manufacturing facilities to develop the product, and expects it to be available within 12 months.

According to Papadoyianis, Ento-Protein will be a major breakthrough for the fish industry, which is not only faced with a supply shortage for bate fish, but has also been slapped with fish meal price increases at a time when demand - for both meal and fish - is on the up.

Neptune Industries also expects its product will play a key role in the market for organic fish. In a climate of increasing interest in organic products, organic fish production has remained an area of uncertainty. Last week, the National Organic Standards Board issued recommendations that fish raised on fish meal-based aquaculture diets be excluded from US Organic Aquaculture Standards. The recommendations require a sustainable source of protein be identified to replace fish meal.

"Most research has centered on the use of vegetable derived protein sources which are inferior in digestibility and assimilation in most carnivorous fish species. These sources often lead to a significant decrease in growth in animals fed these diets," said Papadoyianis.

"Ento-Protein is a superior dietary protein source derived from select insect species produced in a sustainable fashion under controlled conditions. Our goal is to provide our industry with a high quality, sustainable protein source for aquaculture diets that complies with U.S. Organic Standards."

Another reason why Neptune Industries will begin by targeting organic and natural fish production is that such niche market segments are generally in a position to accept higher prices. Once the firm fine-tunes its production, it expects it will "bring cost benefits to the industry".

Papadoyianis told FoodNavigator-USA.com that the insect protein could ultimately also be used in human nutrition. However, it would likely face market resistance due to an instinctive repulsion in the US against consuming insect based ingredients. But the ingredient could be positioned as a means to fortify diets in developing countries, where it could contribute to combating malnutrition.

animal nutrition

An experiment to determine the chemical composition and protein quality of 13 fish substrates (pollock by-products, n = 5; fish protein hydrolysates, n = 5; and fish meals, n = 3) was conducted. Two of these substrates, salmon protein hydrolysate (SPH) and salmon meal with crushed bones (SMB), were used to determine their palatability as components of dog diets. Pollock by-products differed in concentrations of CP, crude fat, and total AA by 71, 79, and 71%, respectively, and GE by 4.1 kcal/g. Fish protein hydrolysates and fish meals were less variable (approximately 18, 14, and 17%, and 1.4 kcal/g, respectively). Biogenic amine concentrations were much higher in fish protein hydrolysates as compared with pollock by-products and fish meals. Pollock liver and viscera had the highest total fatty acid concentrations; however, red salmon hydrolysate and SMB had the highest total PUFA concentrations (49.63 and 48.60 mg/g, respectively). Salmon protein hydrolysate had the highest protein solubility in 0.2% KOH. Based on calculations using immobilized digestive enzyme assay values, lysine digestibility of fish meal substrates was comparable to in vivo cecectomized rooster assay values and averaged approximately 90.3%. Also, pollock milt, pollock viscera, red salmon hydrolysate, and sole hydrolysate had comparable values as assessed by immobilized digestive enzyme assay and rooster assays. A chick protein efficiency ratio (PER) assay compared SMB and SPH to a whole egg meal control and showed that SMB had high protein quality (PER = 3.5), whereas SPH had poor protein quality (PER value less than 1.5). However, using whole egg meal as the reference protein, both fish substrates were found to be good protein sources with an essential AA index of 1.0 and 0.9 for SMB and SPH, respectively. In the dog palatability experiments, a chicken-based control diet and 2 diets containing 10% of either SPH or SMB were tested. Dogs consumed more of the SPH diet compared with the control, and similar amounts of the SMB and control diets. The intake ratios for each were 0.73 and 0.52, respectively. Salmon protein hydrolysate was especially palatable to dogs. These data suggest that chemical composition and nutritional quality of fish substrates differ greatly and are affected by the specific part of the fish used to prepare fish meals and fish protein hydrolysates.