Feed Protein Level Research Articles

Feeding strategy and feed protein level affect the gut microbiota of common carp (Cyprinus carpio).

Common carp (Cyprinus carpio) were fed food with different protein concentrations following different feeding regimes, which were previously shown to affect growth, nitrogen excretion and amino acid catabolism. 16S rRNA gene amplicon sequencing was performed to investigate the gut microbiota of these fish. Lower dietary protein content increased microbial richness, while the combination of demand feeding and dietary protein content affected the composition of the gut microbiota. Hepatic glutamate dehydrogenase (GDH) activity was correlated to the composition of the gut microbiota in all dietary treatments. We found that demand-fed carp fed a diet containing 39% protein had a significantly higher abundance of Beijerinckiaceae compared to other dietary groups. Network analysis identified this family and two Rhizobiales families as hubs in the microbial association network. In demand-fed carp, the microbial association network had significantly fewer connections than in batch-fed carp. In contrast to the large effects of the feeding regime and protein content of the food on growth and nitrogen metabolism, it had only limited effects on gut microbiota composition. However, correlations between gut microbiota composition and liver GDH activity showed that host physiology and gut microbiota are connected, which warrants functional studies into the role of the gut microbiota in fish physiology.

Ruminal microbiota and muscle metabolome characteristics of Tibetan plateau yaks fed different dietary protein levels.

The dietary protein level plays a crucial role in maintaining the equilibrium of rumen microbiota in yaks. To explore the association between dietary protein levels, rumen microbiota, and muscle metabolites, we examined the rumen microbiome and muscle metabolome characteristics in yaks subjected to varying dietary protein levels. In this study, 36 yaks were randomly assigned to three groups (n = 12 per group): low dietary protein group (LP, 12% protein concentration), medium dietary protein group (MP, 14% protein concentration), and high dietary protein group (HP, 16% protein concentration). 16S rDNA sequencing revealed that the HP group exhibited the highest Chao1 and Observed_species indices, while the LP group demonstrated the lowest. Shannon and Simpson indices were significantly elevated in the MP group relative to the LP group (P < 0.05). At the genus level, the relative abundance of Christensenellaceae_R-7_group in the HP group was notably greater than that in the LP and MP groups (P < 0.05). Conversely, the relative abundance of Rikenellaceae_RC9_gut_group displayed an increasing tendency with escalating feed protein levels. Muscle metabolism analysis revealed that the content of the metabolite Uric acid was significantly higher in the LP group compared to the MP group (P < 0.05). The content of the metabolite L-(+)-Arabinose was significantly increased in the MP group compared to the HP group (P < 0.05), while the content of D-(-)-Glutamine and L-arginine was significantly reduced in the LP group (P < 0.05). The levels of metabolites 13-HPODE, Decanoylcarnitine, Lauric acid, L-(+)-Arabinose, and Uric acid were significantly elevated in the LP group relative to the HP group (P < 0.05). Furthermore, our observations disclosed correlations between rumen microbes and muscle metabolites. The relative abundance of NK4A214_group was negatively correlated with Orlistat concentration; the relative abundance of Christensenellaceae_R-7_group was positively correlated with D-(-)-Glutamine and L-arginine concentrations. Our findings offer a foundation for comprehending the rumen microbiome of yaks subjected to different dietary protein levels and the intimately associated metabolic pathways of the yak muscle metabolome. Elucidating the rumen microbiome and muscle metabolome of yaks may facilitate the determination of dietary protein levels.

Effects of feed protein levels on Chinese mitten crabs (Eriocheir sinensis) under the rice-crab co-culture model: Performance, nutrient composition, antioxidant capacity and immunity

The Chinese mitten crab is an important aquaculture product in China. Currently, rice-crab co-culture is a novel model that can realize positive interactions. The feed for Chinese mitten crabs cultured in rice fields should be distinguished from other modes, since their culture environment is unique. Therefore, this study designed three experimental groups that were fed 15% (RC1), 25% (RC2), and 35% (RC3) protein, with a natural bait group (RC0) without artificial feeding as the control. The protein nutritional requirements of Chinese mitten crabs in a rice-crab co-culture model were investigated by exploring the indicators of growth performance, nutrient composition, immunity, antioxidant capacity, and economic benefits of different groups. Through a comprehensive discussion of one-way analysis of variance and regression analysis of the data, we obtained the following results: feeds with high-level protein improved the growth performance, quality, and economic benefits of Chinese mitten crabs and reduced their exposure to oxidative stress. Specifically, the contents of major nutrients and flavor-presenting substances, such as free amino acids (FAA), nucleotides, and essential amino acids (EAA), in the edible parts of female crabs in the 35% protein group were significantly higher than those in all other groups. Male crabs fed 25% − 28.08% protein diets showed higher production performance and FAA content. In conclusion, the optimal dietary protein levels for male and female crabs reared in rice fields are different: they are 35% for females, and at least 25% for males. Therefore, for actual crab production, male and female crabs could be cultured separately using different protein baits to reduce bait costs and achieve green and sustainable development.

Investigating the Impact of Varied Dietary Protein Levels on Litopenaeus vannamei: An Exploration of the Intestinal Microbiota and Transcriptome Responses

This study explored the effects of dietary protein levels on Litopenaeus vannamei with its intestinal microbiota and transcriptome responses. Previous studies on the effects of dietary protein levels on L. vannamei have focused on growth performance, antioxidant indices, and digestive enzyme activity, but few studies have been conducted at the microbiological and molecular levels. In this study, five isolipid experimental diets with protein levels of 32% (P32), 36% (P36), 40% (P40), 44% (P44), and 48% (P48) were used in an L. vannamei (0.63 ± 0.02 g) feeding trial for 56 days. At the end of the feeding trial, the growth performance, immunity, intestinal health, and transcriptional responses of L. vannamei were determined. This study demonstrated that higher protein levels (P44) led to superior weight gain and growth rates for L. vannamei, with lower feed conversion ratios (FCR) observed in the P48 and P44 groups compared to the P32 and P36 groups (p ≤ 0.05). The P44 and P48 groups also showed a notably higher protein efficiency ratio (PER) compared to others (p ≤ 0.05), and there was no significant difference between them. Upon Vibrio parahaemolyticus infection, the P48 group exhibited a significantly lower survival rate (SR) within 48 h, while during 72 h of white spot syndrome virus (WSSV) infection, the P44 group had a notably higher survival rate than the P32 group (p ≤ 0.05). Digestive enzyme activity and antioxidant levels in L. vannamei initially increased and then decreased as protein levels increased, usually peaking in the P40 or P44 groups. Lower dietary protein levels significantly reduced the relative abundance of beneficial bacteria and increased the relative abundance of pathogenic bacteria in the intestines of L. vannamei. Transcriptome sequencing analysis revealed that most differentially expressed genes (DEGs) were up-regulated and then down-regulated as dietary protein levels increased. Furthermore, KEGG pathway enrichment analysis indicated that several immune and metabolic pathways, including metabolic pathways, glutathione metabolism, cytochrome P450, and lysosome and pancreatic secretion, were significantly enriched. In summary, the optimal feed protein level for L. vannamei shrimp was 40–44%. Inappropriate feed protein levels reduced antioxidant levels and digestive enzyme activity and promoted pathogen settlement, deceasing factors in various metabolic pathways that respond to microorganisms through transcriptional regulation. This could lead to stunted growth in L. vannamei and compromise their immune function.

Evaluation of the antibacterial activity and protein profiling of Nile tilapia (Oreochromis niloticus) epidermal mucus under different feeds and culture systems (biofloc technology and earthen pond).

The mucus layers of fish serve as the main interface between the organism and the environment. They play an important biological and ecological role. The current study focuses on Nile tilapia epidermal mucus reared under different commercial feeds (coded A and B) and environments (biofloc technology and earthen pond systems). Crude protein levels in feed A and B were 30% and 28%, respectively. Water parameters in all culturing systems were suitable for tilapia throughout the study period. The antimicrobial potency of tilapia (n = 5 from each) epidermal mucus was tested invitro against human and fish pathogenic strains viz. Staphylococcus epidermidis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Francisella noatunensis, and Aeromonas hydrophila. To determine the antimicrobial activity, zones of inhibition (ZOI) were measured in millimetres and compared with two antibiotics (chloramphenicol and ciprofloxacin). SDS-PAGE analysis was performed on skin mucus samples of tilapia to determine protein quantity and size (molecular weight). Results of tilapia skin mucus (crude and aqueous) revealed a strong antibacterial effect against all the selected pathogenic strains. However, variation has been observed in the mucus potency and ZOI values between the biofloc and pond tilapia mucus. The crude mucus of tilapia fed on feed A and cultured in the pond exhibited strong antibacterial effects and high ZOI values compared to the mucus of biofloc tilapia, aqueous mucus extracts and positive control chloramphenicol (antibiotic). The SDS-PAGE results showed that the high molecular weight proteins were found in the collected epidermal mucus of BFT-B (240 kDa) and EP-B (230 kDa). Several peptides in fish skin mucus may play a crucial role in the protection of fish against disease-causing pathogens. Thus, it can be utilized in the human and veterinary sectors as an 'antimicrobial' for treating various bacterial infections.

PSIX-5 Spray Dried Plasma Increases Protein and Meat Inclusion in Extruded Dog Kibbles

Abstract A common goal for pet food manufacturers extruding dry kibbles is to increase meat inclusion and protein content in both grain and grain free formulas. When extruding high meat formulas, variation of moisture and fat of the incoming raw meat ingredients adds to the complexity of producing consistent quality kibbles meeting all specifications. Spray dried plasma (SDP) is a consistent high protein ingredient commonly utilized in wet pet food for water binding and fat emulsification characteristics and in dry kibble extrusion with meat meals and other dry ingredients to produce quality kibbles. Thus, the objective of two studies was to evaluate if meat inclusion levels could be increased in extruded formulas with the use of SDP. Tests were done at the Wenger technology testing center to evaluate combinations of SDP levels ranging from 2.5 to 20% with meat level feed rates ranging from 25 to 50%. The ability to produce kibbles was conducted utilizing both grain free and grain formulations. Processing conditions were monitored on the various formulations during production along with kibble outcome measurements such as ability to extrude, solids, protein, and durability. In the first study, extrusion of grain free formulations with 0% SDP resulted in meat inclusion limit at 35% feed rate. Addition of 5, 10, and 15% SDP in grain free formulas increased protein content of the extruded kibble but meat inclusion was limited at 35% feed rate. However, use of 20% SDP in grain free formulas allowed for greater inclusion of meat from 35% and up to 45% feed rate while maintaining kibble quality and increasing protein. Extrusion of a grain formulation with 0% SDP also resulted in limits of 35% feed rate of meat inclusion. Addition of 2.5, 5, 10, or 20% SDP to grain formulations allowed for meat inclusion feed rate to be increased up to 50% depending on levels of SDP used, and protein was increased in all combinations. The second study was completed to evaluate a longer run extrusion measuring ability to extrude, cook, and durability. Grain free formulas were run at 35% feed rate of meat with 5, 10, or 20% SDP and maintained cook and durability. Grain formulas were run at 45% feed rate of meat with 2.5, 5, and 10% SDP and maintained durability with further optimization of cook needed. Overall, SDP included in the formulation allows for greater feed rate of meat inclusion and maintain or increase protein and durability in the dry kibble. Thus, depending on target meat inclusion feed rates or protein levels, SDP may be used during the extrusion process to produce dry kibbles with high meat inclusion.

Evaluasi Pengaruh Level Kandungan Protein dalam Pakan terhadap Respons Super Ovulasi: Kajian Meta-Analisis

The purpose of this study was to evaluate and analyze the effect of the level of protein content in feed on the superovulation response in cattle through a meta-analysis study. The meta-analysis study was performed with OpenMEE application and used scientific articles from international journals according to the topic of the study. The superovulation parameters used in this study were the number of corpus luteum, the number of collected embryos, the number of viable embryos, degenerated embryos, unfertilized embryos, and the proportion of viable embryos. The results of a meta-analysis of 37 research results in 20 scientific articles showed feed protein level had a significant effect on increasing the number of corpus luteum, collected embryos, viable embryos, and the proportion of viable embryos. Meanwhile, the feed protein level had no significant effect on degenerated embryos and unfertilized ovum. It could be concluded that an increase in feed protein content had a positive effect on several reproductive quality parameters.&#x0D; Key words: cow, embryo, feed, protein, reproduction, superovulation

The effect of feeding with different protein levels on internal organ weight and gene expression of MEF2A and ATF3 in crossbred local chicken using RT-PCR

BackgroundMyogenic enhancer transcription factor 2A (MEF2A) is a transcription factor known for its role in controlling skeletal muscle regeneration and metabolic processes, while activating transcription factor 3 (ATF3) is a stress-induced transcription factor that plays a role in modulating metabolic processes, immunity, and oncogenesis. Environmental factors, such as dietary protein, can influence gene expression levels. Insufficient protein intake can negatively affect the metabolic performance of internal organs, leading to the abnormal weight of internal organs. A total of 192 non-sexing crossbred local chickens day-old-chick (DOC) with a completely randomized design (CRD) method of 3 treatments and 8 replicates. Real-time polymerase chain reaction (RT-PCR) is used to measure the gene expression levels. This study aimed to determine the effect of feeding with various protein levels on internal organ weight and gene expression of MEF2A and ATF3 in crossbred local chickens. ResultThe analysis of treatment revealed that the results were not significantly different (P > 0.05) on gizzard weight and spleen weight. However, it shows a significantly different result (P < 0.05) on heart weight and a highly significantly different result (P < 0.01) on pancreas weight. These findings suggest that protein levels in the diet had a significant impact on heart and pancreas weights. In terms of gene expression, the increased utilization of protein did not result in an elevation of MEF2A gene expression in both muscle tissue and liver tissue. Specifically, in muscle tissue, MEF2A gene expression was highly expressed at 18% protein feed for the starter phase and 16% for the finisher phase. Conversely, in liver tissue, MEF2A gene expression was highly expressed at 22% protein feed for the starter phase and 20% for the finisher phase. Moreover, ATF3 gene expression in muscle tissue exhibited a negative correlation with increasing feed protein levels. ConclusionThe results indicate that varying protein levels did not lead to abnormal weights in the liver, kidney, heart, and spleen organs. Additionally, the differential gene expression patterns of MEF2A and ATF3 in muscle tissue and liver tissue suggest that these genes respond differently to varying protein-feeding treatments. These findings provide insights into the complex regulatory mechanisms of MEF2A and ATF3 genes in relation to protein levels and organ-specific responses in crossbred local chickens.

The addition of guanidino acetic acid with different protein levels in feed on the growth performance and drumstick meat quality of broiler chicken

Guanidino acetic acid, or GAA, is the only direct precursor of creatinine and is involved in biological processes in the cellular energy of vertebrates. Creatine will be used in muscle and target cells to be phosphorylated into phosphocreatine utilizing creatine kinase, which functions to buffer ATP changes. GAA is involved in the biosynthesis of cellular energy for growth and muscle performance of broiler chickens, and it is also claimed to be capable of conserving arginine. This study employed a 2x3 factorial experimental design with two levels of protein (i.e., high and low) and three levels of GAA (i.e., 0 g/ton, 600 g/ton, and 1,200 g/ton) fed to 1,176 Indian River strain broiler chickens that were reared for 35 days. The R program was used to analyze the data, and if there was a significant difference, the Duncan multiple range test was performed. The results demonstrated that adding GAA on feed with different protein levels did not improve broiler performance. However, the addition of 1,200 g/ton GAA in low protein could reduce the cholesterol levels of broiler drumstick meat. Meanwhile, adding 600 g/ton GAA combined with the low protein treatment had the highest tenderness value. Therefore, to achieve the ideal proportion and enhance the performance and quality of broiler meat, GAA can continue to be added to broiler chicken feed.

The Effect of Feed Protein Levels on The Growth of Kissing Gourami (Helostoma temminckii)

Kissing gourami culture has begun to be developed to reduce the dependence on natural catches. Many factors that are influence fish culture. One of those is the availability of sufficient quantity and quality feed. Protein is an important nutrient that supports fish growth and affects feed prices. The protein requirement for each fish needs to be known as a basis for formulating feed. This research aims to determine the optimum feed protein level for kissing gourami. This study used a completely randomized design with five treatments and three replications. The treatment given is different levels of feed protein, consisting of 25% (P0), 30% (P1), 35% (P2), 40% (P3), and 45% (P4). The result showed that feed protein level 35% (P2) gave the best result for kissing gourami which resulted a absolute weight growth of 0.45 g, absolute length growth of 0.24 cm, protein efficiency ratio of 0.49, and feed efficiency of 17.11%.

Analysis of the effects of dietary crude protein on growth performance and antibiotic susceptibility of microflora isolated from all-male tilapia (Oreochromis niloticus)

The aquaculture industry is one of the fastest-growing sectors in the food industry. The Nile tilapia, Oreochromis niloticus, is an important and inexpensive species of fish. A study was conducted to determine the effects of divergent dietary crude proteins on fish growth performance and antibiotic susceptibility of bacterial pathogens infecting all-male tilapia (Oreochromis niloticus). Forty-eight fish samples were grouped into three groups based on crude protein percentages, including 15%, 30%, and 45%, and the fish's body weight and length were measured on days 15, 30, 45, and 60. Ordinary one-way ANOVA (Tukey's multiple comparison test) was applied to three divergent dietary crude protein groups for the examination of growth performance at different time points. Using the same fish samples, bacterial strains were isolated from fish skin and gills and identified based on their morphological characteristics and biochemical testing. Kirby Bauer's disc diffusion method was used to determine the antibiotic susceptibility of identified bacterial isolates. The ANOVA (Tukey's multiple comparison test) results showed that 45% crude protein level in fish feed led to a greater growth rate than 15% and 30% under high-performance conditions. The antibiotic susceptibility findings indicate that Staphylococcus aureus showed the highest sensitivity (50%) toward antibiotics while Pseudomonas aeruginosa showed the least susceptibility (10%). The study provides a new perspective on the impact of crude protein on fish growth performance, as well as baseline information for the management of fish diseases based on antibiotic sensitivity.

АКТИВНОСТЬ ДУОДЕНАЛЬНЫХ ФЕРМЕНТОВ В ПОСТЭМБРИОНАЛЬНЫЙ ПЕРИОД ОНТОГЕНЕЗА ЦЫПЛЯТ-БРОЙЛЕРОВ КРОССА «СМЕНА 9» ПРИ РАЗНОМ УРОВНЕ ПРОТЕИНА В РАЦИОНЕ

The work has been dedicated to study of age changes in digestive enzymes and alkaline phosphatase activ- ity in duodenum tissues in “Smena 9” cross broilers in ontogenesis postembryonic period with changes of raw protein level in start feed. The results of poultry intestine tissue gomogenate investigation at this stage have shown amylase, lipase and alkaline phosphatase activity decreasing and also protease activity increasing comparing these traits in day age. Raw pro- tein content increasing in feed by 1.5% in the first 14 days of raising has increased intestine proteases activity in 21–35 days in comparison with the control group. Therefore first two weeks of raising are one of the critical periods in broiler ontogenesis and feeding and maintaining disturbances in this period influence sufficiently the next broiler development stages.

EFFECT OF PROBIOTIC SUPPLEMENTATION AND VARYING DIETARY PROTEIN LEVELS IN CREEP FEED ON GROWTH PERFORMANCE OF SALT RANGE LAMBS

Main aim of this work was to findout the influence of probiotic supplementation and suitable dietary protein level in creep feed for optimum growth performance of Salt Range lambs. Lambs (n ₌ 16; Age ₌ 30±10 days) were chosen and divided into four equal groups. Four dietary treatments; diet-1 (CP 18% with no probiotic), diet-2 (CP 18% with probiotic), diet-3 (CP 20% with noprobiotic) and diet-4 (CP 20% with probiotic) were randomly allocated to lambs under Completely Randomized Design. The raw data were analyzed through ANOVA technique using SAS 9.3 software. The growth performance was determined in terms of average daily gain, average daily feed intake, feed conversion ratio, feed cost per kg gain and blood parameters; hemoglobin, blood glucose, blood urea and blood cholesterol. Results indicated that average daily gain of lambs fed diets having 20% proteinwith and without probiotic supplementation are not different (P&gt;0.05), whereas average daily gain of lambs fed 20% protein was found higher (P&lt;0.05) than of those fed 18% protein with and without probiotic supplementation. Average daily feed intake was found higher (P&lt;0.05) in diet-3 than diet-2 but remained not different in animals fed diet-1 and diet-4. Lambs fed dietary protein 20 percent were found more efficient (P&lt;0.05) in terms of feed conversion ratio than that of 18 percent protein. Bloodparameters were found not different by various dietary treatments. It was inferred that creep feed with probiotic supplementation couldn’t influence growth but higher dietary crude protein 20% in creep feed improved growth performance of Salt Range lambs in pre-weaning phase.

Supplementation of guanidinoacetic acid in feed with different levels of protein on intestinal histomorphology, serum biochemistry, and meat quality of broiler

This study aimed to investigate the effect of guanidinoacetic acid (GAA) with different protein levels in feed on intestinal histomorphology, serum biochemistry, and meat quality of broiler chicken. GAA is the only direct precursor of creatine and is involved in the synthesis of bioenergy cellular. This research used 1.176 day-old chicks of the Lohmann Indian River strain that were reared for 35 days. The supplementation effect was investigated using six treatments, i.e., two levels of feed protein and three levels of GAA, with seven replications. Broiler chickens were fed with 23% and 21% crude pro-tein during the pre-starter phase, 21% and 19% during the starter phase, and 19% and 17% during the finisher phase, with a GAA addition of 0 g/ton, 600 g/ton, and 1200 g/ton, respectively. The result showed GAA supplementation with different protein levels reduced triglyceride (P&lt;0,05), cholesterol levels in serum (P&lt;0,05), increased surface area of the microvilli (P&lt;0,05), pH of breast meat (P&lt;0,05), but did not affect the chemical quality of breast meat (P&gt;0,05). In conclusion, GAA supplementation in different level protein diets increased the surface area of the microvilli, pH of breast meat, reduce se-rum cholesterol and triglycerides, without affecting the chemical quality of broiler meat.

Effects of dietary protein levels on growth performance, muscle composition and fiber recruitment of juvenile small yellow croaker (Larimichthys polyactis)

This study investigated the effect of protein levels (PLs) in dietary feed on the growth performance, muscle composition, and fiber recruitment in juvenile small yellow croaker (Larimichthys polyactis). A total of 900 fish weighing 10.67 ± 0.07 g were randomly allocated into six groups that were fed dietary PLs of 40%, 42.5%, 45%, 47.5%, 50%, and 52.5%, respectively. Each group was sorted into 1.0 × 1.0 × 1.0 m3 cages, with 50 individuals per cage. The fish were fed for 50 days; thereafter, all of live fish were analyzed for weight and length, 15 individuals per group were randomly selected for sampling and analysis. The weight gain rate and specific growth rate significantly increased when the dietary PL increased from 40% to 47.5% (P < 0.05). The lowest feed conversion rate was 1.32 when the dietary PL was 46.40%. The crude protein content in the muscle of juvenile L. polyactis was increased when dietary PL increased from 40% to 45%. Compared to dietary PL of 40%, dietary PL of 45% significantly improved accumulation of glutamic acid, valine, threonine, isoleucine, leucine, phenylalanine, serine, arginine, and lysine in the juvenile L. polyactis muscle. The muscle morphology revealed that a dietary PL of 47.5% could significantly promote the generation of small-sized fibers (semidiameter < 20 µm). Furthermore, changes in relative mRNA expression of paired box-7, myogenic differentiation factor D, and myogenin influenced the muscle fiber tendencies. Our results indicate that the optimum dietary PL range for both body and muscle growth of juvenile L. polyactis is between 47.33% and 47.50%.

Effect of L-arginine and L-Lysine HCl ratio on growth performance and ileum morphology of native chickens aged 2-14 weeks.

Background and Aim:Micronutrients such as essential amino acids in chicken feed must be balanced to promote optimal development. The balance of the amino acids arginine and lysine in chicken feed is particularly important. This study aimed to examine the effect of the ratio of L-arginine to L-Lysine HCl on growth performance and ileum morphology of native chickens aged 2-14 weeks-old.Materials and Methods:One hundred and eighty 2-week-old native chickens which initial weight 78.10±4.97 g were classified into six treatments and five repetitions using a completely randomized design.Treatments were based on the ratio of arginine to lysine in the feed:T1 (0.50% L-arginine: 0.85% L-lysine HCl); T2 (0.75% L-arginine: 0.85% L-lysine HCl); T3 (1.00% L-arginine: 0.85% L-lysine HCl); T4 (0.50% L-arginine: 1.00% L-lysine HCl); T5 (0.75% L-arginine: 1.00% L-lysine HCl); and T6 (1.00% L-arginine: 1.00% L-lysine HCl).Results:Groups T3 and T6 had the highest feed consumption (42.06±0.29 and 42.78±0.72 g/bird/day, respectively), while Group T6 had the highest body weight and body weight gain rate (1505.60±103.20 kg/bird and 16.99±1.24 g/bird/day, respectively). Groups T3 and T6 also had the highest carcass weight (916.16±46.99 and 947.18±62.32 g/bird, respectively). The best feed conversion was seen for Groups T3, T5, and T6 (2.55±0.14, 2.50±0.20, and 2.53±0.19, respectively). For ileum morphometry, the highest villus height occurred in Groups T2, T3, T5, and T6 (962.80±23.31, 982.80±10.03, 972.80±18.99, and 989.80±10.69 μm, respectively); and Group T6 had the highest crypt depth and villus width (340.80±11.52 and 302.00±4.00 μm, respectively). Statistical analysis indicated significant differences among the treatment groups for all variables examined (p<0.05).Conclusion:The highest ratio of arginine-lysine was associated with the largest increase in native chicken feed consumption, body weight gain, feed conversion, and carcass weight, as well as villus height and width, and crypt depth in the ileum. Overall, an arginine-lysine ratio of 0.8-1.20 promoted optimal growth of native chickens aged 2-14 weeks. In the future, it is important to increase the arginine-lysine ratio with low feed protein levels in native chickens.

Bioconversion of chitin waste through Stenotrophomonas maltophilia for production of chitin derivatives as a Seabass enrichment diet

Marine wastes pose a great threat to the ecosystem leading to severe environmental hazards and health issues particularly the shellfish wastes. The shellfish waste which contains half of the amount of chitin can be efficiently transformed into useful products. Various approaches for the hydrolysis of chitin like physical, chemical, and enzymatic processes are there. Still, the use of enzyme chitinase is well documented as an effective and eco-friendly method. The present study summarizes the isolation of chitinase enzyme producing bacteria from different shrimp waste disposal sites in Parangipettai (India), and the possible use of an enzyme hydrolyzate as an immunostimulant to Asian Seabass (Lates calcarifer). The potential chitinase-producing bacteria were identified by 16S rRNA gene sequencing as Stenotrophomonas maltophilia. After purification, the chitinase specific activity was 5.01 (U/ml) and the protein content was 72 mg and the recovery rate was 48.06%. The optimum pH and temperature for the chitinolytic activity were 6.5 and at 35–50 °C, respectively. The animal experiment trial was done with our feed supplements which included 0.0 (control), 0.5%, 1% and 2% of chitin degraded product. All the supplementary feed had an optimal 42% (w/w) of crude protein. The feed protein level was 41–43% on average and gross energy was 13–17 kcal/g and the feed was observed to exhibit a significantly higher (p < 0.05) survival rate, condition factor, specific growth rates, and body weight gain was also found to be promising compared to other fishes fed with control diet only. The red blood cells (RBC) and white blood cell (WBC) counts were found to increase significantly after being challenged with infection in animals fed with chitin derivatives from 1st week to 3rd week when compared to the control. The hematocrit (Hct) values were low on the 2nd and 3rd week in infected fish fed with chitin derivatives. This low level was due to infection lyses of the red blood cells and increased nitro blue tetrazolium reduction. The control diet-fed fish showed 70% mortality but the chitin derivative supplemented fishes showed only 20% mortality post-infection. The results of the study encompass that the use of chitin-derivate enriched feed further is taken into large-scale approaches thereby benefitting the aquaculture sector.

The evaluation of protease enzyme effectivenes in broiler chicken diet containing jack bean seed (Canavalia ensiformis) with different protein level toward internal organ size

This study was conducted with the intention of evaluating the use of the protease enzyme in broiler feed containing jack bean seed (Canavalia ensiformis) with the different levels of protein towards the internal organs of broiler chicken starter. Bird samples used were 24 broilers of the male lohmann strain taken from 120 chickens. The study design used was a factorial completely randomized design (FCRD) with 2 factors treatment and 3 replications (each replication used 2 samples of bird). The first factor was the level of protein (CP 22% and CP 19.5%) and the second factor was the use of enzymes (non-protease and protease). Data were analyzed by using analysis of variance (ANOVA). The result showed that the use of low protein levels in broiler feed containing jack bean seed significantly (P <0.05) increased the percentage of pancreatic weights but could be improved by the use of protease enzymes. Levels of protein treatment did not significantly affect the percentage of heart, liver and bile weights. The use of protease enzymes significantly (P <0.05) decreased the percentage of pancreatic and bile weights but did not significantly affect the percentage of liver and heart weights.

Effects of feed energy and protein level on growth and pelt parameters in blue foxes (Vulpes lagopus) in the late growing-furring period

The aim of the present study was to determine whether a decrease in feed energy content would prevent extreme body weight (BW) gain and fatness in blue foxes in the late growing-furring period, without compromising pelt quality or pelt size. BW gain, body mass index (BMI), body condition score (BCS), and pelt characteristics were studied in 60 blue foxes divided into four equal-sized groups from mid-October until pelting (50 days). Experimental diets in were “high energy – high protein”, “high energy – low protein”, “low energy – high protein”, and “low energy – low protein”. High-energy diets contained 19.3 MJ metabolisable energy (ME) in kg dry matter (DM) and high-protein diets contained digestible crude protein (DCP) 20% of ME. Low-energy diets contained 16.3 MJ ME in kg DM and low-protein diets DCP 17% of ME. Feeding was gradually increased towards ad libitum. Reduced ME intake had no effect on pelt size or pelt quality. High-energy feeds resulted in heavier animals with higher BMI. However, the final BW exceeded 20 kg and BCS was “fat” or “extremely fat” in all groups.

PRODUCTIVITY OF RAINBOW TROUT DEPENDING ON PROTEIN LEVELS IN PRODUCTIVE FEED

The article considers the efficiency of using complete feeds with different levels of protein in rearing commercial rainbow trout. The purpose of the experiment was to establish the effect of different protein levels in nutrition of two-year old trout on its productivity. For this purpose, five experimental groups were formed by the method of analogues. During the equalizing period, the experimental fish consumed feed of the control group. In the main period, the protein level in trout feed ranged from 44 to 52 % per 1 kg. As a result of the studies it was established that the increase of protein content in compound feed from 48 to 52 % leads to an increase in the weight of commercial fish by 13.0 % (p &lt; 0.001), an increase in its growth intensity – by 7.4-16.7 %, while the reduction of protein in feed to 44 % leads to a reliable (p &lt; 0.05) reduction in trout weight by 9.4 %, and a decrease in its growth intensity - by 6.5-12.1 %. It is proved that different levels of experimental trout’s protein nutrition have a highly reliable (p &lt; 0.001) effect on the growth of marketable fish - the share of this factor’s influence is 89.8 %. Analysis of the feed costs, proves that using combined feed with 52 % protein for feeding two-year old trout, leads to a decrease in feed costs per 1 kg of weight gain by 5.1 %, whereas reducing this index to 44% causes increase of feed costs by 6.4 % per a unit of product, compared to feeding fish with production feed having the protein content of 48 %. At this, the preservation of experimental fish was high enough and made 94.3 to 96.2 %. In rearing trouts according to the criteria of maximum productivity, it is recommended to feed commercial trout with production combined feeds with the protein level of 52 %, whereas, in production according to the economic optimization criteria, this index should make 48 %.