Influence of Salinity on Protein Requirements of Rainbow Trout (Salmo gairdneri) Fingerlings

1973 ◽  
Vol 30 (12) ◽  
pp. 1867-1873 ◽  
Author(s):  
I. H. Zeitoun ◽  
J. E. Halver ◽  
D. E. Ullrey ◽  
P. I. Tack

Rainbow trout (Salmo gairdneri) juveniles maintained at 10 and 20 ppt salinity were fed seven diet treatments from 30 to 60% protein in 5% increments for 10 weeks. The fish were stocked in cones, initially 50 fish per cone. Biweekly weights of diets and fish were determined and mortality was recorded daily. Percentage weight gain, gross diet efficiency, and protein efficiency ratio (P.E.R.) were computed. The minimum protein levels required for fish to achieve highest performance using these criteria were 40 and 45% for those maintained at 10 and 20 ppt, respectively. Mortality was significantly (P < 0.05) higher for fish maintained at the higher salinity. Analyses of the fish carcasses were conducted at the beginning and end of the experiment on representative samples to estimate the grams protein retained and apparent net protein utilization (N.P.U.) to verify the above findings. All the available data showed that dietary protein was of major consequence on all measurements until the minimum required level of protein in the diet was reached, while salinity was of minor consequence. P.E.R. and apparent N.P.U. were 2.10 and 34.4, respectively, for casein diets at the 40% protein level.

1974 ◽  
Vol 31 (6) ◽  
pp. 1145-1148 ◽  
Author(s):  
Ibrahim H. Zeitoun ◽  
Duane E. Ullrey ◽  
John E. Halver ◽  
Peter I. Tack ◽  
W. T. Magee

Six purified diets ranging from 30 to 55% protein in 5% increments were fed for 10 wk to duplicate groups of coho salmon (Oncorhynchus kisutch) smolts maintained at 10 or 20‰ salinity. The data indicated that minimum protein requirements did not differ for fish at either salinity, and weight gain and protein retention levelled off after 40% protein in the diet was reached. Salinity had a minor effect on the criteria measured whereas the different dietary protein concentrations were of major consequence. The protein efficiency ratio (PER) of the casein diet containing 40% protein was 2.20 ± 0.11 whereas apparent net protein utilization (NPU) at the same level was 36.1 ± 1.8.


1982 ◽  
Vol 47 (3) ◽  
pp. 615-624 ◽  
Author(s):  
B. W. Ince ◽  
K. P. Lone ◽  
A. J. Matty

1. Three isoenergetic test diets containing 320, 430 and 530 g protein/kg, with (experimental) and without (control) inclusion of an anabolic steroid, ethylestrenol, were given to rainbow trout (Salmo gairdneri) of mean initial weight 27 g, for 60 d.2. After 60 d, all trout groups were given an identical, steroid-free, commercial diet (410 g protein/kg) for a further 30 d, to observe withdrawal effects on growth.3. The weight and length of trout given the 430 and 530 g protein/kg control diets were significantly greater after 60 d than those given the 320 g protein/kg control diet.4. Inclusion of steroid enhanced the weight and length of trout given the 320 and 430 g protein/kg experimental diets, exerting a preferential effect on weight as opposed to length.5. After steroid withdrawal, a significant difference between the weight and length of the 320 g protein/kg control and experimental groups was still apparent.6. An increase in dietary protein increased the food conversion efficiency, and decreased the protein efficiency ratio. Inclusion of steroid increased both these factors over the respective controls.7. Protein assimilation decreased, and faecal nitrogen content increased with increasing dietary protein. In trout given steroid, protein assimilation and apparent digestibility was higher, and facecal N content, lower than the controls.8. Muscle protein increased with increasing dietary protein, and was higher in trout given steroid.9. Relative liver weight increased with increasing dietary protein. Inclusion of steroid resulted in a reduction in relative liver and gut weight, and an increase in kidney weight.10. It is concluded that ethylestrenol promotes both the growth and efficiency of nutrient utilization of trout. The magnitude and duration of these effects are a function of the dietary protein level.


1965 ◽  
Vol 43 (11) ◽  
pp. 1879-1883 ◽  
Author(s):  
M. A. Krishnaswamy ◽  
S. B. Kadkol ◽  
G. D. Revankar

Ensiled fish was prepared from a local variety of freshwater fish (Barbus carnaticus) by fermentation with a pure culture of Streptococcus lactis, commercial lactose being used as a source of fermentable carbohydrate. The fermented material (pH 4.7) was roller dried. The finished product was cream colored and had a somewhat aromatic odor. It had a protein content of about 72%. Total lysine, available lysine, methionine, cystine, and tryptophan of the ensiled fish (expressed as g/16 g N) were 10.1, 8.1, 3.6, 1.1, and 1.2%, respectively. Hygienically, the product, being free from coliforms, enterococci, Salmonella, coagulase-positive staphylococci, and pathogenic anaerobes, was satisfactory. The biological value of the product as determined by protein efficiency ratio (3.3), net protein utilization (82.3%), and net protein ratio (4.2) was not significantly different from that of skim milk powder, which has a protein efficiency ratio of 3.2, net protein utilization of 82.8%, and net protein ratio of 4.9.


2017 ◽  
Vol 30 (6) ◽  
pp. 817-826
Author(s):  
Silvana Mariana SREBERNICH ◽  
Gisele Mara Silva GONÇALVES ◽  
Semíramis Martins Álvares DOMENE

ABSTRACT Objective To evaluate the protein quality and iron bioavailability of a fortifying mixture based on pork liver. Methods Determinations of protein efficiency ratio, net protein utilization, true digestibility and hemoglobin regeneration efficiency by depletion and repletion were performed. In the depletion phase, the animals (male Wistar rats) received an iron-free AIN–93G diet and in the repletion phase they received the following diets: standard AIN–93G diet, fortifying mixture and standard diet containing heptahydrated ferrous sulfate for comparison. Results For standard AIN–93G diet and fortifying mixture the results were 3.75 and 4.04 for protein efficiency ratio and 3.53 and 3.63 for net protein retention, showing that the presence of pork liver in the diet promoted an increase in protein efficiency ratio and net protein retention (not statistically significant). True digestibility results obtained with the fortifying mixture (97.16%) were higher than those obtained with the standard AIN–93G diet (casein), but without significant difference. The hemoglobin regeneration efficiency values obtained for standard AIN–93G diet, fortifying mixture and standard diet containing heptahydrated ferrous sulfate were 50.69, 31.96 and 29.96%, respectively, showing a statistically significant difference between the control (standard AIN–93G diet) and test (fortifying mixture and standard diet containing heptahydrated ferrous sulfate) samples, but not between the test samples. Conclusion The fortifying mixture showed a high protein efficiency ratio value of 4.04 and a high relative biological value (108%) and it can be added to soups, creams and meats in day-care centers for the prevention of iron-deficiency in children of school age.


2021 ◽  
Author(s):  
Nurul Inayaht

Pengertian dari ilmu gizi (nutrition science) adalah “ Ilmu yg mempelajari segala sesuatu tentang makanan dalam hubungannya dengan kesehatan optimal”. Karbohidrat merupakan senyawa organik yang terdiri dari unsur karbon (C), hidrogen (H), dan oksigen(O) . Fungsi Karbohidrat adalah sebagai Sumber energi, pemberi rasa manis pada makanan, penghemat protein, pengatur metabolisme lemak, membantu pengeluaran feses. Lemak adalah senyawa organik yang larut dalam pelarut non polar seperti etanol, kloroform dan benzena, tetapi tidak larut dalam air. Lemak mengandung karbon , hidrogen dan oksigen. Fungsi umum lemak di dalam tubuh adalah menghasilkan energi terkonsentrasi yang memberikan kalori sebesar 9 kal/gram.Protein terdiri atas rantai-rantai panjang asam amino yang terikat satu sama lain dalam ikatan peptide. Asam amino terdiri atas unsur-unsur karbon, hidrogen, oksigen dan nitrogen, unsur nitrogen adalah unsur utama protein, Mutu protein ditentukan melalui : Nilai Biologik (NB), Net Protein Utilization (NPU), Protein Efficiency Ratio (PER), dan Skor Kimia (Skor Asam Amino). Vitamin adalah senyawa organik yang tersusun dari karbon, hidrogen, oksigen, dan terkadang nitrogen atau elemen lain yang dibutuhkan dalam jumlah kecil agar metabolisme, pertumbuhan dan perkembangan berjalan normal. Vitamin dapat dipilahkan menjadi 2 kelompok yaitu kelompok yang larut dalam lemak dan yang larut dalam air. Mineral berdasarkan kebutuhan digolongkan menjadi mineral makro dan mineral mikro.


1980 ◽  
Vol 63 (3) ◽  
pp. 462-467 ◽  
Author(s):  
J Murray Mclaughlan ◽  
G Harvey Anderson ◽  
L Ross Hackler ◽  
Douglas C Hill ◽  
G Richard Jansen ◽  
...  

Abstract An interlaboratory study involving protein efficiency ratio (PER), net protein ratio (NPR), relative NPR (RNPR) and relative nitrogen utilization (RNU) was carried out. Six collaborators assayed 6 samples, including casein plus methionine which was used as a reference protein. Collaborators prepared their own diets and analyzed the diets for nitrogen. Test proteins were added at the 8% level (N × 6.25). PER values varied more than NPR values which varied more than either RNPR or RNU. RNU and RNPR produced almost identical values, but RNPR remains the official method of choice, because it is a well established method.


1984 ◽  
Vol 67 (3) ◽  
pp. 621-622
Author(s):  
Muriel L Happich ◽  
C E Bodwell ◽  
L Ross Hackler ◽  
John G Phillips ◽  
Philip H Derse ◽  
...  

Abstract Apparent nitrogen digestibility data were obtained from 4 laboratories for 6 protein sources and 2 diet levels, 6 and 10% protein, after a 2-day adaptation period during the AACC–ASTM protein efficiency ratio (PER) and net protein ratio (NPR) collaborative studies. For 5 protein sources fed as 10% of the diet, the interlaboratory variation as measured by coefficient of variation (CV) values was low (1.5–3.5%), indicating high precision of the method. Wheat flour (6% protein diet) had the highest variation and, therefore, the lowest precision (CV of 7.10%). The interlaboratory variation (CV value) for 3 of the 4 laboratories was considerably lower, less than half that for the 4 laboratories. An analysis of variance of apparent nitrogen digestibility data indicated significant (P &lt;0.05) effects for the 4-Iaboratory group due to laboratories and protein diets at both 10 and 6% protein levels, and for the 3-laboratory group at the 10% protein level. The 3-laboratory ANOVA for the 6% diets indicated a significant effect (P &lt;0.05) due to diet only.


1991 ◽  
Vol 53 (1) ◽  
pp. 119-122 ◽  
Author(s):  
L. Velasquez ◽  
I. Ibañez ◽  
C. Herrera ◽  
M. Oyarzun

Worm meal obtained from worms (Eisenia fetida) raised on waste materials was evaluated for Rainbow trout as a replacement for fish meal at dietary concentrations of 250, 500 and 1 000 g replaced per kg. During the study period none of the diets was detrimental to fish health. The dietary concentrations of 250 and 500 g/kg replacement gave higher growth rates than that of the control group (0 g/kg replacement), the former having consumed less food. The biological parameters of food conversion efficiency and protein efficiency ratio, for these replacement levels, also showed values better than the control diet. Liver somatic index and the chemical composition of fish fillets showed no significant differences between diets, except for a significant decrease in lipid content with increasing worm meal inclusion.


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