Isonitrogenous Semi-purified Diets Research Articles

High dietary lipid level alters the growth, hepatic metabolism enzyme, and anti-oxidative capacity in juvenile largemouth bass Micropterus salmoides.

The present study was conducted to investigate the effects of high dietary lipid levels on growth, metabolism, antioxidant capacity, and immune responses of largemouth bass. Fish (initial body weight 13.38 ± 0.11g) were fed three isonitrogenous semi-purified diets containing 5%, 10%, and 20% lipid, respectively. The results indicated that fish fed 10% lipid diet showed significantly better final body weight, specific growth rate (SGR), protein efficiency ratio (PER), and feed conversion ratio (FCR) compared with that fed 5% lipid diet. Meanwhile, fish fed 20% lipid diet had a significantly higher viscera ratio (VR), hepatosomatic index (HSI), intraperitoneal fat ratio (IPF), and liver lipid content than those fed the other diets. Higher alanine aminotransferase (ALT) and aspartate transaminase (AST) activities, total cholesterol (TC), triglyceride (TG), free fatty acids (FFA), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) contents, and LDL-C/HDL-C value in plasma were recorded in fish fed 20% lipid diet, while higher insulin contents were obtained in fish fed 5% lipid diet. In addition, the highest carnitine palmitoyltransferase I (CPT1), AMP-activated protein kinase (AMPK), fructose-1,6-bisphosphatase (FBPase), and phosphoenolpyruvate carboxykinase (PEPCK) activities in the liver were also observed in fish fed 20% lipid diet. However, fish fed 20% lipid diet had a significantly lower superoxide dismutase (SOD) and catalase (CAT) activities and higher MDA contents in liver than those fed the other diets. The higher nitric oxide (NO) contents and inducible nitric oxide synthase (iNOS) activity in liver were recorded in fish fed 10% lipid diet. Moreover, the alkaline phosphatase (ALP), inducible nitric oxide synthase (iNOS) and lysozyme activities, and nitric oxide (NO) contents in plasma were higher in fish fed the 10% diets than the other groups. In conclusion, high dietary lipid levels could suppress growth performance and liver anti-oxidative capacity, and reduce immune responses of largemouth bass.

Physiological Responses of Golden Mahseer (Tor putitora) Fry to Dietary Zinc and Assessment of its Optimum Requirement

Effect of dietary zinc on growth, survival and physiological responses of Tor putitora fry was investigated. A 60-day experiment was conducted with 1,800 fry (avg. wt 54.35 ± 3.09 mg) of golden mahseer distributed randomly among six treatments in triplicate. Six isonitrogenous semi-purified diets were prepared with graded levels of zinc (0, 10, 20, 40, 60 and 80 mg/kg). Zinc sulphate was added as dietary zinc source to the basal diet. Zinc concentration in rearing water was monitored during feeding period and it was set from 0.01 to 0.03 mg/L. Growth parameters as average weight gain, percentage weight gain, feed efficiency ratio were higher (p < 0.05) in fish fed diets with 40 mg Zn/kg. Suppressed growth and higher mortality was observed in groups fed with 80 mg Zn/kg diet. RNA/DNA ratio and whole body zinc retention showed increasing trend with increasing dietary zinc up to 40 mg Zn/kg and plateaued thereafter. Analysis of digestive enzymes revealed that amylase activity increased with increase in dietary zinc levels however, lipase and protease showed rhythmic changes among treatment groups. There was an increasing trend of alkaline phosphatase (ALP) activity with increase in zinc supplementation and highest ALP activity was observed in 80 mg Zn/kg diet which was significantly different from that of control group. Polynomial regression analysis indicated that 44.62–46.73 mg Zn/kg diet is optimum requirement, which favoured enzymatic responses for optimal growth and survivality in T. putitora fry.

Effects of different sources of dietary non-starch polysaccharides on the growth performance, development of digestive tract and activities of pancreatic enzymes in goslings

1. The purpose of this study was to investigate the effects of different sources of dietary non-starch polysaccharides (NSP) on growth performance, development of gastrointestinal tract, and activities of pancreatic enzymes in goslings from 0 to 21 d of age. 2. A total of 100 one-day-old White Roman female goslings were selected and randomly divided into 5 dietary treatment groups. Each group had 4 replicate cages (100 × 60 × 58 cm) of 5 goslings. Goslings in each group were given one of 5 isoenergetic and isonitrogenous semi-purified diets. Experimental diets were designed to contain 90 g/kg of different sources of dietary NSP from maize (control), barley hull, rice bran, wheat bran, or pectin, respectively, and 97·4 g/kg NSP were supplied by soybean meal. 3. The goslings receiving the pectin diet had significantly higher viscosity in intestinal digesta than the other treatment diets. However, the daily feed intake, daily weight gain, and feed conversion ratio of goslings in the pectin group were significantly lower than those given the other diets. 4. The relative weights of proventriculus, gizzard, liver and pancreas, as well as the relative weights and lengths of various intestinal segments in the goslings that received the pectin diet, were significantly higher than those receiving the other diets. The specific activities (SA) of amylase, lipase, trypsin, and chymotrypsin in the pancreatic tissue of goslings in the pectin group were significantly lower than those in the other groups. 5. Goslings given a soluble NSP source (pectin) diet tended to exhibit inhibited growth and decreased activity of pancreatic enzymes. However, compared with maize, the inclusion of insoluble NSP sources from barley hull, rice bran, and wheat bran did not negatively affect growth and also were not significantly different among the treatment diets.

Formulation of Semi-Purified Diets for Striped Bass, Morone saxatilis, Larvae

2 Abstract: Recent years have witnessed a dramatic rise in the intensive culture of striped bass, Morone saxatilis due to its reduced supply from capture fisheries and high market price. One of the major problems that limit its mass culture is non-availability of seed in sufficient quantities due to unreliability of live feeds and their high cost, Artemia for example. The main objective of these studies was, complete replacement of live food with artificial diets or at least reduce its quantity in larval food without compromising growth and survival of fish. Based on the chemical composition of natural zooplankton, the presumed ideal diet for striped bass larvae. various iso-caloric and iso-nitrogenous semi-purified diets were formulated. The chemically analyzed ingredients were homogenously blended, microencapsulated and fed to larval fish. Commercial starter diets were also used for comparison. There were two feeding trials. Eight and 12-day-old striped bass was used in trial 1 and 2 respectively. Former had 9 dietary treatments and was continued for two weeks. Instar I live Artemia nauplii and zooplankton served as control while their encapsulated forms were secondary controls. Fish fed on live Artemia and zooplankton exhibited the highest growth and survival comparatively lower in zooplankton fed group. Encapsulated live food ranked second. Fish in the rest of the treatments could gain only 0.1-5.8 mg and survival ranged just from 25-43%. Later trial, on the other hand, had 11 treatments and lasted four weeks. Same age and weight larval fish, were fed on live Artemia (control) nauplii, Artemia capsules and casein based semi-purified diet. All the diets were processed following the same procedures as implied in former trial. But unlike previous trial tannic acid was incorporated in encapsulation material of some of the diets to enhance capsule stability and dropped in others. Similarly betain was included in selected inert diets to boost diet acceptability. Some of the inert diets were also periodically supplemented with live Artemia nauplii. Fish reared on live Artemia maintained its superiority in growth and survival over its counterparts. Tannic acid containing diets with periodic supplementation of live Artemia gave 40-50% survival and reasonable growth while performance in rest of the treatments remained very poor. Fish grew only up to 11-25 mg and survival could not exceed 25%. It appears that striped bass larvae can not digest microcapsules due to poorly developed digestive system.

Utilization of different raw and pre-gelatinized starch sources by juvenile yellowfin seabream Sparus latus

Raw corn starch (RCS), raw tapioca starch (RTS), raw potato starch (RPS), pre-gelatinized corn starch (PCS), pre-gelatinized tapioca starch (PTS) and pre-gelatinized potato starch (PPS) were evaluated as starch sources in diets for yellowfin seabream Sparus latus in a 56-day growth trial. Seven isonitrogenous semi-purified diets comprising a non-starch cellulose control diet and the six different starch sources holding 200 g kg−1 starch each were prepared and fed to triplicate groups of juvenile yellowfin seabream S. latus. Fish were fed for 8 weeks. Weight gain (WG) and specific growth rate (SGR) for fish fed RCS, RTS and RPS diets were equal, as well as for fish fed PCS, PTS and PPS diets, but values in groups fed the raw starch sources were significantly higher compared with fish fed the pre-gelatinized starches. Feed efficiency and protein efficiency ratio in fish fed different starch source diets showed no significant differences but were significantly higher than those fed a non-starch control diet. Protein productive value was improved by starch incorporation to diets. PCS, PTS or PPS groups showed lower feed intake compared with RCS, RTS or RPS groups, and the differences were significant between PCS, PPS and RCS, RPS groups. Whole-body protein and ash contents and muscle compositions were not affected by different starch sources. Whole-body and liver lipid contents, liver moisture and glycogen contents were significantly affected by starch source. Values of hepatosomatic index, intraperitoneal fat ratio, viscerosomatic index and condition factor did not vary between experimental treatments. Plasma total protein concentration for RCS, RTS or RPS fed fish was significantly higher than that for PCS, PTS or PPS fed fish, but significantly lower than that for non-starch fed fish. Plasma cholesterol and triacylglycerol concentrations were unaffected by starch source, but were significantly higher in fish fed the non-starch control diets. Plasma glucose concentrations in all dietary groups were relatively stable. In conclusion, raw corn, tapioca and potato starches at a 200 g kg−1 inclusion level were well utilized as energy sources by yellowfin seabream, which was evidenced by better WG and SGR. Pre-gelatinization of the starches had no positive effect on starch utilization.

Effects of dietary lipid sources on growth and fatty acid composition of juvenile shrimp, Litopenaeus vannamei

This experiment was conducted to evaluate the effects of dietary lipid sources on the growth performance and fatty acid (FA) composition of juvenile shrimp, Litopenaeus vannamei. Six isoenergetic and isonitrogenous semi-purified diets containing casein, solvent-extracted soybean meal and gelatin as protein sources, were supplemented with 60 g kg−1 of lipid sources. The lipid sources included: pollack fish oil (PO), pork lard (PL), soy oil (SO), peanut oil (PN), rapeseed oil (RO) and a mixture of pollack fish oil and soy oil (POSO 1 : 1 w/w). Each diet was fed to juvenile shrimp (0.10 g average weight) four times daily in triplicate tanks to apparent satiation (feeding ratio was about 8%) for 8 weeks. At the end of the experiment, weight gain, specific growth rate and protein efficiency ratio were significantly higher for shrimp fed the diet containing PO and the POSO mixture oil than the other lipid sources. The nutritional values of SO, RO, PN and PL were similar. Shrimp fed on PO, mixture oil of POSO and SO had better survival rates than the other lipid sources, and shrimp fed the PL had the lowest survival rate. There were significant differences in lipid contents of whole body and hepatopancreas amongst the dietary treatments; however, lipid contents of tail muscle were not significantly affected by the dietary lipid sources. Shrimps fed POSO diet had higher protein content in whole body than those fed the other lipid sources, and shrimp fed PO diet had highest crude protein content of the tail muscle. A high correlation was found between dietary FA composition and FA composition of whole shrimp. FA composition of the whole body was generally affected by dietary lipid sources, especially dietary unsaturated FA.

Comparative study on the effect of dietary lipid level on growth and feed utilization for gibel carp (Carassius auratus gibelio) and Chinese longsnout catfish (Leiocassis longirostris Gunther)

An 8-week growth trial investigated the effect of dietary lipid level on growth performance of a carnivorous fish, Chinese longsnout catfish (Leiocassis longirostris Gunther) and an omnivorous fish, gibel carp (Carassius auratus gibelio). For each species, seven isonitrogenous semi-purified diets (455 g kg(-1) crude protein for Chinese longsnout catfish and 385 g kg(-1) crude protein for gibel carp) were formulated to contain 30, 60, 90, 120, 150, 180 or 210 g kg(-1) lipid. For Chinese longsnout catfish, feed intake (FI) decreased with increasing dietary lipid and there was no significant difference in feed intake from 90 to 210 g kg(-1) lipid. Specific growth rate (SGR) increased with dietary lipid level (P < 0.05) and the 150 and 180 g kg(-1) groups were the best. Feed conversion efficiency (FCE), protein retention efficiency (PRE) and energy retention efficiency (ERE) were higher at 180 g kg(-1) lipid. For gibel carp, FI decreased with increased dietary lipid and 180 and 210 g kg(-1) lipid groups showed lower values. SGR increased with dietary lipid level and the 150 and 180 g kg(-1) were the best. FCE was higher at 180 g kg(-1) lipid level. PRE increased with dietary lipid level and there was no significant difference in groups from 120 to 210 g kg(-1) dietary lipid. ERE increased with increasing dietary lipid level, and groups fed 120, 150 and 180 g kg(-1) lipid showed the highest values. In Chinese longsnout catfish, increase in dietary lipid level, resulted in increased carcass dry matter, crude protein, crude lipid and gross energy. In gibel carp, dry matter, crude protein, and crude lipid increased with dietary lipid level. Based on regression between SGR and dietary lipid, dietary lipid requirements for Chinese longsnout catfish and gibel carp were 142.6 and 140.5 g kg(-1), respectively.

The effects of dietary lipid levels on the growth response of juvenile mud crab Scylla serrata

This experiment was conducted to evaluate the level of dietary cod liver oil/corn oil (2:1, w/w) mixture needed for maximum weight gain of juvenile mud crab. Seven isoenergetic and isonitrogenous semi-purified diets, with lipid levels ranging from 0 to 12% in 2% increments were evaluated. After termination of the experiment, crabs fed the diets without the oil addition and 2% added oil had significantly lower weight gains than those fed the other diets. Also, crabs fed the diet without oil addition had the lowest molting frequency among the groups. Survival of crabs ranged from 93.3 to 100% for all groups. A dietary lipid level ranging from 5.3 to 13.8% appears to meet the lipid requirement for this crab species.

An estimate of the dietary calcium requirement of fingerling Tilapia aurea reared in calcium-free water

Seven isocaloric and isonitrogenous semi-purified diets which contained graded levels of calcium ranging from 0.17 to 3.20% were fed to fingerling Tilapia aurea for a period of 11 weeks. The fish were maintained in a flow-through aquarium system supplied with calcium-free well water. Growth, feed conversion and bone composition data indicated that between 0.17 and 0.65% dietary calcium was adequate for optimum growth and normal bone mineralization.