Intenzivni uzgoj smuđa (sander lucioperca) u Rumuniji: stanje i perspektive

Smuđ je jedna od najvrednijih slatkovodnih vrsta riba sa dobrom tržišnom perspektivom u Evropskim zemljama. Na osnovu Rumunskog Operativnog Programa za ribarstvo i maritimne poslove 2014-2020, u narednim godinama će biti podržano uvođenje u Rumunsku akvakulturu novih vrsta visoke ekonomske vrednosti, naročito domaćih vrsta kao što je smuđ i novih tehnologija gajenja za ovu vrstu. Tako će nove farme koje koriste intenzivnu tehnologiju gajenja smuđa imati bolje šanse nego u prošlosti da dobiju finansijsku pomoć. U svakom slučaju 5 novih ribnjaka sa recirkulacionim sistemom za gajenje smuđa su projektovani i izgrađeni u poslednje 2-3 godine. Ovi ribnjaci imaju, bar delimično, aktivnosti usmerene na intenzivno gajenje smuđa. U svakom slučaju, prisutni su različiti stadijumi implementacije projekta (od projekta do pune aktivnosti), ali nijedan nije zaokrižio proizvodni process gajenja smuđa u intenzivnom sistemu.Pikeperch is one of the most valuable freshwater fish species having a good market perspective in European countries. According to Romanian Operational Program for Fisheries and Maritime Affairs 2014-2020, the introduction in Romanian aquaculture of new species with high economical value, especially indigenous species like pikeperch, and new technologies for these species, will be supported in the next years. Therefore, new fish farms applying intensive technology for pikeperch culture could have a better chance to get financial support than in the past. Anyway, five new fish farms with units intended for pikeperch aquaculture in recirculating aquaculture system (RAS) already started to be designed and built in the last 2-3 years. These farms have at least partially activities in the direction of intensive pikeperch farming. Anyway, different stages of implementation of the projects (from design to running activity) were found at this moment, none of them completing a production cycle for pikeperch reared in intensive system

Gajenje slatkovodnih riba u centralnoj i istočnoj Evropi: potrebe za istraživanjem i razvojem

Gajenje slatkovodinih riba ima veoma važnu ulogu za stabilizaciju biodiversiteta, resursa podzemnih voda, klime regiona kao i za snabdevenost hranom u Centralnoj i Istočnoj Evropi. Velika konkurencija cena ribe na međunarodnom tržištu i promene u navikama ishrane ljudi pojačavaju pritisak na mala i srednja preduzeća u Centralnoj i Istočnoj Evropi koja se bave gajenjem ribe i mogu da ugroze predeo oko uzgojnih jezera. Da bi povećali vrednost svih karika u lancu proizvodnje slatkovodnih riba, naučnici i proizvođači su identifikovali uobičajene i potencijalne izazove. Da bi se procenile potrebe sektora akvakulture u centralnoj i istočnoj Evropi, sprovedeni su polu strukturirani intervjui sa proizvođačima i prerađivačima ribe i udruženjima u Poljskoj i Češkoj, u okviru projekta SIAD i FP7 EU projekta TRAFOON. Takođe su održane radionice sa istraživačima u sektoru akvakulture duž svake karike lanca proizvodnje riba u Centralnoj i Istočnoj Evropi. Različite interesne strane su identifikovale nekoliko izazova koji ometaju razvoj slatkovodne akvakulture u Centralnoj i Istočnoj Evropi. Razvoj akvakulture zahteva postojanje harmonizovanog regulativnog/pravnog okvira. Razmena znanja bi imala pozitivan uticaj na razvoj uniformnih standarda za održivost, i pomogla bi stvaranju pravnih procedura za izdavanje dozvola i licenci. Potrebno je izvršiti ekonomsku procenu usluga koje ekosistem ribnjaka pruža. Poboljšana tehnoligija koja je povoljna po životnu sredinu i sistemi za upravljanje kvalitetom u proizvodnji i preradi su neophodni da bi se obezbedila ustaljenija ponuda proizvoda od ribe viskog kvaliteta. Potrošači treba da budu bolje informisani o funkciji koju slatkovodna akvakultura i njeni proizvodi imaju za životnu sredinu. Da bi došlo do održivog razvoja sektora akvakulture i da bi se izgradilo poverenje javnosti, veoma je važno podstaći društvene inovacije koje su primenljive na pojedinačni sektor ili pojedinačnu teritoriju. Da bi došlo do održivog razvoja sektora slatkovodne akvakulture potrebno je razviti strategije makro regionalnog razvoja koje su prilagođene određenim tržištima, uslovima životne sredine, ponašanju potrošača, kulturi i tradiciji i koje nude potencijal za razvoj izvan granica jedne zemlje. Razvoj i adaptacija ključnih tehnologija potrebni su da bi se stabilizovala konkurentna i održiva proizvodnja i prerada ribe u čijoj su proizvodnji resursi efikasno iskorišćeni

Study On The Effects of Polyculture of the Sterlet (Acipenser Ruthenus) Fingerlings and European Catfish (Silurus Glanis) on Bioproductive Performances of These Species in Recirculating Aquaculture Systems

The aim of this study was to evaluate the effects of polyculture of the sterlet (Acipenser ruthenus) fingerlings with european catfish (Silurus glanis) (20 – 30%) into recirculating aquaculture system on growth dynamic of the fish and tank’s bioproductivity. Two variants of polyculture have been tested during a period of 42 days in duplicate: V1-sterlet with 20% catfish (600 sterlets and 120 catfish); V2-sterlet with 30% catfish (600 sterlets and 180 catfish). The control group (C) contains sterlet in monoculture (600 sterlets). After 42 days of polyculture of the sterlet fingerlings with catfish 20% (V1) or 30% (V2) there were no significant differences (p>0.05) in sterlets’ growth dynamic among the three variants. The bioproductive indices were better in the polyculture variant where sterlets were farmed with 30% catfish. Polyculture of catfish and sterlet could be a good way to positively influence the fingerling sterlet farming in RAS, having a beneficial impact on tank’s bioproductivity. A significant plus of fish biomass (catfish) resulted by means of valorisation of the unconsumed food by the sterlet, was obtained in both polyculture variants

Correlations and Interdependencies of the Main Morphological Traits in Sterlet (Acipenser ruthenus) Fingerlings, Reared in Recirculating Aquaculture System

The aquaculture of the sturgeons from the Danube River basin is a niche approached by more and more Romanian entrepreneurs. The sterlet (Acipenser ruthenus) is a fresh water sturgeon with some useful characteristics that recommend this species to become a good candidate for intensive aquaculture in RAS. The monitoring of the growth dynamic of the sterlet or any other fish species reared in controlled conditions is very important for the fish farm management, especially for setting and adjustment of the technological parameters that directly influence the growth performances. The aim of this study is to evaluate the correlations and functional dependencies between some morphological traits, like total and standard length, maximum body depth and body weight in sterlet fingerlings reared exclusively into recirculating aquaculture system (RAS). Our results clearly demonstrated that any of the four body measurements (total length, standard length and maximum body depth and body weight) could be monitored in sterlet fingerlings, to accurately assess the growth dynamic, the correlations among these being very high (ranging from 0.982296 to 0.999778). Moreover, the dependencies of these traits are very high. Three of measurements could be calculated based on sterlet body weight with our equations

Evaluation of Russian sturgeon (Acipenser gueldenstaedtii) Semen Quality and Semen Cryopreservation

The alarming decline in sturgeon populations doubled by growing demands for sturgeon products, urge us to prevent the loss of these species. Fish stocking in natural habitats and developing fish farms are viable solutions, which can be successfully implemented with the help of reproductive biotechnologies. Despite the fact that semen cryopreservation is admittedly an important step for saving the Russian sturgeon, a reproducible standard method with good results has yet to be identified. Sperm quality assessment is essential for quantifying the impact of cryopreservation on spermatozoa. The purpose of our study was to provide additional information regarding semen cryopreservation and semen quality evaluation for the Russian sturgeon. Our study method is based on the use of two yolk-free extenders (with different cryoprotectants: DMSO and methanol) for freezing semen, using a simple freezing protocol. Parameters such as volume, concentration, motility, morphology and membrane integrity were evaluated. In conclusion, cryopreservation of Russian sturgeon spermatozoa using an extender containing methanol as cryoprotectant led to high egg fertilization percentages (72.67 ± 5.4%) even if the total motility values recorded for thawed semen were quite low (18–25%). Additionally, we identified two optimal stains for morphological studies and morphometry (Spermac stain kit and Trypan Blue Solution)

The Polyculture of Sterlet (Acipenser ruthenus) and Carp (Cyprinus carpio) in Recirculating Aquaculture Systems. The Effects on Fish Growth Dynamic and Production

The polyculture of two or more fish species is very common in ponds, this fish culture technique being relatively newly applied in recirculating aquaculture systems (RAS). The aim of this study is to evaluate the effects of polyculture of the sterlet (Acipenser ruthenus) and common carp (Cyprinus carpio) (30-60%) into recirculating aquaculture system on growth dynamic of the fish and tank’s bio-productivity. Two variants of polyculture have been tested during a month in duplicate: V1 - sterlet with 30% carp (200 sterlets and 60 carps/ 1 m3 tank); V2 - sterlet with 60% carp, (200 sterlets and 120 carps/1 m3 tank). The control group (C) contains sterlet in monoculture (200 sterlets/ 1 m3 tank). The polyculture for 28 days of the sterlets with carps 30% (V1) or 60% (V2) did not significantly (p>0.05) influence the sterlets’ growth dynamic. Bio-productive parameters were better in the polyculture variant where sterlets were farmed with 30% carps. Polyculture could be a good way to positively influence the fingerling sterlet farming in RAS, having a beneficial impact on tank’s bio-productivity. A significant plus of fish biomass (carp) resulted by valorisation of the pellets unconsumed by the sterlet, was obtained in both polyculture variants

Research on Some Factors Influencing the Milk Production Indices in Romanian Black and White Cows

Researches were carried out in 60 dairy farms rearing 658 Romanian Black and White (RBW) cows. Dairy cows were enrolled in the official performance control, performed by a local association. Farms were categorized by size (number of dairy cows) as small (≤10), medium (11-25) and large (>25), according to the specific conditions in Hunedoara County. Besides the farm size, the influence of calving season and parity was assessed on the milk production indices: milk yield, fat percentage and yield, and protein percentage and yield. Maturity equivalent (ME) milk, fat and protein yields were 50% (p<0.01) higher in large farms (7549± 87.44 kg milk, 309.6± 4.05 kg fat, and 252.9± 2.90 kg protein) than in medium and small farms. Fat and protein percentages in milk increased as cows grew older (by 3-5%, p<0.001). Calving season had a significant influence on ME milk production indices, as well (p<0.01). Thus, milk yield, fat yield, fat percentage and protein yield were higher in winter calvings (7175.9 kg vs. 7060.8 kg, 292.1 kg vs. 286.1 kg, 4.1% vs. 4.0% and 247.9 kg vs. 237.6 kg, respectively), while milk protein percentage was higher in summer calvings (4.3% vs. 3.6%)

Study on the Influence of the Coriander (Coriandrum sativum) on the Chemical Composition of the Muscle in European Catfish (Silurus glanis)

European catfish (Silurus glanis) plays an important role in aquaculture due to its fast growth rate, its resistance to different environmental conditions, its adaptability to different rearing systems and the high nutritional and qualitative properties of the meat. Studies by many researchers have proven that coriander (Coriandrum sativum) has beneficial biological effects in fish, but studies regarding its or other phyto-additives influence on the meat quality of European catfish are sparse. The current study aimed to evaluate the influence of coriander seeds powder as phyto-additive (2 and 4%) in dry food pellets given to the European catfish, on chemical composition of its muscle. The coriander seed powder was administered 14 weeks in fish feed in two trials in duplicate: 2% and 4% to one-year-old European catfish. Three hundred fish were randomly selected and stocked into 6 tanks, 50 fish per tank. At the end of the experiment, 5 fish were collected from each tank, euthanized and used for the evaluation of the muscle quality. A piece of epaxial muscle from the highest part of the body was sampled, and subjected to the assessment of the crude protein and fat content, ash and moisture. The results revealed that coriander do not have a significant influence on muscle quality in general, but led to a significant (p£0.01) decrease of crude fat content