Unga wa samaki ni chanzo bora cha protini kinachomeng’enyeka vizuri kwa samaki wa baharini, lakini gharama, upatikanaji mdogo na ukuaji wa aquaculture huifanya ipunguzwe. Protini za mimea ni mbadala, lakini upungufu wa essential amino acids na antinutritional components unaweza kudhoofisha ukuaji, digestion na gut health kwa samaki walao nyama.

Utafiti ulichunguza kama low molecular weight protein hydrolysates kutoka mabaki ya baharini zinaweza kuwa kiungo cha kazi katika feeds zenye fish meal kidogo. Shrimp head hydrolysate, salmon viscera hydrolysate na pelagic marine fish hydrolysate ziliwekwa katika mlo wa juvenile red seabream, Pagrus major.

Samaki 576 walilishwa diets 6 kwa wiki 10. Matokeo bora zaidi yalionekana katika SH10 yenye %10 shrimp hydrolysate: ukuaji, FCR, PER, digestibility, innate immunity na gut morphology viliboreshwa. Final body weight na weight gain za SH10 hazikutofautiana kitakwimu na HFM. Katika Edwardsiella tarda challenge, survival ilikuwa juu kwa nambari katika hydrolysate groups, lakini haikuwa significant.

Tatizo kuu

Red seabream ni samaki wa thamani kubwa hasa Korea Kusini na Japani. Kwa kuwa ni carnivorous fish, huhitaji animal protein ya ubora wa juu. Fish meal hutoa digestible protein, amino acid profile nzuri, palatability, fatty acids na minerals, lakini uzalishaji wake ni mdogo na gharama yake ni kubwa.

Kikomo cha protini za mimea

Plant proteins zinaweza kuwa na lysine na methionine kidogo, protease inhibitors, non-starch polysaccharides na athari kwa feed intake, gut structure na protein utilization. Kupungua kwa performance ya LFM dhidi ya HFM kulihusishwa na vikwazo hivi vya lishe.

Hydrolysate na molecular weight

Protein hydrolysate hutokana na kuvunja protein kubwa kuwa short peptides na free amino acids. Peptides chini ya 1000 Da hufikiriwa kufyonzwa kirahisi zaidi. Katika shrimp na marine fish hydrolysates, %91,9 ya peptides ilikuwa chini ya 1000 Da na %82,4 chini ya 500 Da; salmon hydrolysate ilikuwa na %82,7 chini ya 1000 Da na %69,5 chini ya 500 Da.

Diets na experimental design

Feeds zilikuwa takribani %49,9 crude protein na %13,1 crude lipid. Samaki 576 wenye initial weight 41,10 ± 0,16 g waliwekwa katika 18 tanks za 240 L, samaki 32 kwa tank, replicates 3 kwa diet, kwa wiki 10.

Growth formulas na matokeo

\[ WG(\%) = \frac{W_f-W_i}{W_i} \times 100 ] [ SGR(\%/\text{gün}) = 100 \times \frac{\ln W_f-\ln W_i}{\text{gün}} ] [ FCR = \frac{\text{verilen kuru yem}}{\text{ıslak ağırlık artışı}} ] [ PER = \frac{\text{ıslak ağırlık artışı}}{\text{verilen toplam protein}} \]

SH10 ilikuwa na FCR ya chini zaidi na PER ya juu zaidi. Ukuaji haukuelezwa tu na kula zaidi, kwa sababu feed intake ya juu zaidi ilikuwa HFM.

Digestibility, gut na immunity

ADC ilihesabiwa kwa %1 chromic oxide. SH10 ilionyesha dry matter %69,4, protein %85,7, lipid %85,7, carbohydrate %65,5 na energy %81,5. Villus height katika SH10 ilikuwa 1064 µm dhidi ya 805 µm katika LFM; goblet cells 1052 dhidi ya 587. Lysozyme ilikuwa 0,77 µg/mL, MPO 1,87, NBT 1,03 na SOD %79,9.

Liver, genes na challenge

AST/ALT zilikuwa chini zaidi katika SH10: 41,9 U/L na 14,2 U/L. Kati ya FAS, CPT, FABP, PPAR-α na PPAR-β, FABP pekee ilibadilika significantly. Edwardsiella tarda challenge ilitumia 1,2 × 10⁸ CFU/mL na 50 µL kwa samaki; survival ilikuwa %50 katika SH10 na %36 katika LFM, lakini difference haikuwa significant.

Nguvu, mapungufu na maana

Nguvu ni samaki 576, replicates 3, feeds zenye protein/lipid sawa, na tathmini ya growth, digestibility, immunity, gut, microbiota na genes. Mapungufu ni preprint status, species moja, wiki 10, tank conditions, hakuna economic analysis, challenge isiyo significant, microbiota ya culture-based na support ya kampuni. Matokeo yanaonyesha kuwa hydrolysates haziwezi kuthibitisha kuondoa fish meal kabisa, lakini zinaweza kusaidia partial replacement.

Mbinu na Matokeo ya Utafiti

Maelezo ya Chanzo na Mbinu

Maudhui haya yanatokana na kazi ya Saumya Poorni, Sanghyun Song, Thomas Levallois na Kyeong-Jun Lee yenye kichwa “Low Molecular Weight Marine Protein Hydrolysates as Fish Meal Substitutes Enhance Growth, Nutrient Digestibility, Innate Immunity and Gut Health in Red Seabream (Pagrus major)”. Utafiti ni SSRN preprint na haujapitia peer review. Matokeo hayawezi kujumlishwa moja kwa moja kwa commercial farming, species zote au total fish meal replacement.