نشریه علوم آبزی پروری پیشرفته
سال پنجم شماره 2 (پاییز و زمستان 1400)

Zander (Sander lucioperca) is a valuable species with desired specifications like high growth rate and delicious meat which makes it so appropriate for aquaculture goals and subsequently, its cultivation has begun in many countries around the world during recent two decades. This species is endemic to Iranian southern Caspian Sea basin and has high commercial value in this region, but unfortunately, over harvesting and habitats destruction has led to diminish of its natural stocks. Therefore, introduce of this species for aquaculture purposes in different culture systems such as earthen ponds, raceways, cages and recirculating facilities is very important. According to high commercial importance of pikeperch in Iran and other countries, looks that access to biotechniques of propagation and rearing and also, determining environmental and nutritional requirements of this fish could lead to development in aquaculture of this valuable species in future. Therefore, the current paper tried to review methods for propagation and rearing of pikeperch.

In aquaculture industry, genomic selection has a profound potential to improve the genetic programs and production systems. Genomic selection benefits from both the actual relationship between animals and information from genomic markers in strong LD with commercially and biologically important genes. In this paper, technical progresses, practical requirements and commercial applications of genomic selection in aquaculture will be discussed. Using cost-effective genome sequencing, the genotyping capability in all type of organisms even those with no previous genetic knowledge has been provided. Usage of genomic selection proposes advantages more than traditional aquaculture through accurate estimation of polygenic complex traits such as disease resistance, increase the genetic gain, minimizing the inbreeding and negating the limiting effects of genotype by environment interactions. Based on the performed studies, implementation of a genomic selection program can reduce the rates inbreeding up to 81%. At the moment, the genomic selection is now at the position which can be involved in commercial breeding programs to suggest long and/or short term solutions towards reaching the commercial sustainable aquaculture.

In this research, extension recommendations have been expressed in order to achieve a suitable structure for the production and breeding of tilapia in a greenhouse system equipped with biofloc technology. For this purpose, three international designs of fish farming systems in a greenhouse system equipped with biofloc technology were reviewed. These three structures include the main biofloc reservoir and sedimentation tank, breeding tank with middle cone - external discharge line, and two-stream reservoir system. In this regard, the required equipment for each structure was presented parametrically and the economic evaluation of the structures was done in order to select the structure with the lowest cost. A comparison of all three structures was performed for a capacity of 60 tons. Common equipment in all structures includes an 85 cubic meter tank with skeleton and sheet structure and polycarbonate cover / per square meter. Cost analysis on the electricity consumption index showed that the cost of energy consumption in plan 3 is higher, so that it is about 8 times more than plan 2 and about 13 times more than plan 1. But in terms of the cost of building the required tanks, plan 3 is optimal. Therefore, according to the needs of breeding farms and the specific restrictions of each region, one of the plans 1 or 3 can be implemented.

Gelatin is a protein, colloidal, and the oldest macromolecule obtained from the hydrolysis of collagen in the skin, bones, and connective tissue of animals, including livestock, poultry, and aquatic animals. By-products or wastes make up more than half the weight of aquatic animals. Bones and skin make up a significant portion of aquatic waste and are composed of connective tissue proteins that provide the potential for gelatin production. Due to the properties and benefits of gelatin such as low calorie, fatlike melting, and pleasant mouthfeel, its use for low-fat products seems appropriate. In the food industry, the most important characteristics of gelatin are the strength of the gel, viscosity, gel state, and melting point, so gelatin is a good choice for diet and low-calorie products. Preparation of gelatin consists of several stages including pretreatment with acid and alkali, neutralization, heating, liquid phase separation, concentration, drying, grinding, and packaging in air-impermeable packages. This article examines the importance of gelatin and its preparation methods, types of gelatin, and how to prepare gelatin from aquatic animals.

Pathogens are always one of the threats to the aquaculture industry. Sometimes diseases can cause irreparable damage. Herpesvirus (KHVD) is one of these diseases that has affected many countries in the world, including our country. The disease only affects common carp (Cyprinus carpio) and its various breeds such as Koi fish. All age groups of common carp are susceptible to this virus. The disease occurs at temperatures above 16°C. Unfortunately, there is no specific treatment for this viral disease, and if it occurs, 80-100% of the common carp in the farm may be lost. On the other hand, fish left over from the disease are likely to carry the virus and can spread it to other groups. Fortunately, the herpes virus, which causes KHV in fish, does not cause disease in humans, so manipulating or even consuming these fish does not pose a risk to humans. Unfortunately, there is still no effective vaccine to protect farmed fish against the virus. Unfortunately, there is still no effective vaccine to protect farmed fish against the virus. Therefore, the best way to deal with it is to prevent and strictly observe the biosafety regulations in fish farms. In case of this disease, it is necessary for the breeder to inform the Veterinary and Fisheries Department in order to prevent further spread of the disease while receiving expert guidance and assistance.

Sea bass is a member of the Latidae family, which two Asian species (Lates calcarifer) and European (Dicentrarchus labrax) are more popular for breeding, and most research related to this fish is focused on these two species. Having a normal range of biochemical and hematological parameters, also known as blood table, is important in research related to this fish. In this regard, by reviewing the authoritative sources published during the last 50 years in the databases of PubMed, Google Scholar, Islamic World Citation Database and Jahad Daneshgahi database, this information includes the normal range of glucose, cholesterol, triacylglycerol, total protein, albumin, blood enzymes, hormones; Thyroid, cortisol, testosterone and blood electrolytes as well as the number of red blood cells and related parameters and the number of white blood cells are scientifically collected and classified so that it can be used as a coherent source in related research.