Dry Diet Research Articles

Effects of dry pelleted diets on growth and survival of the edible sea urchin Arbacia stellata (Blainville, 1825) for an echinoculture feasibility

Effects of dry pelleted diets on growth and survival of the edible sea urchin Arbacia stellata (Blainville, 1825) for an echinoculture feasibility

Body Composition of Healthy Cats and Cats with Chronic Kidney Disease Fed on a Dry Diet Low in Phosphorus with Maintenance Protein.

The aim was to evaluate the effect of feeding a low-phosphorus and maintenance protein diet in healthy cats and cats with chronic kidney disease (CKD) with IRIS stages 1 (CKD-1) and 2 (CKD-2). Cats were initially fed a senior diet (30 days) followed by the renal diet (60 days). Body composition, body weight (BW), muscle mass score (MMS), and body condition score (BCS) were assessed before (T30) and after renal diet intake (T60). General mixed linear models were used to assess the effects of fixed groups and moments (T30 × T60), as well as their interaction, in addition to the random effects of animals within each group. Unlike healthy cats and cats with CKD-1, cats with CKD-2 had a loss of BW, lower BCS (p < 0.005), and lower MMS (p = 0.0008) after 60 days of consuming the renal diet. The fat mass and lean body mass (LBM), determined by the deuterium isotopes method, did not change in all cats between T0 and T60. In healthy cats and cats with CKD-1, the renal diet resulted in maintenance of BW, BCS and MMS; but cats with CKD-2 presented lower BCS and did not reduce phosphatemia after consumption.

Home-cooked diets cost more than commercially prepared dry kibble diets for dogs with chronic enteropathies

Nutrition plays a fundamental role in the management of canine chronic enteropathies (CCEs). Dog owners may elect to feed home-cooked diets (HCDs) rather than veterinary commercially prepared diets (CPDs) because of perceived lower costs. There is a paucity of data comparing costs of these options. We hypothesize there will be differences in costs between complete and balanced HCDs and nutritionally comparable CPDs. 6 Home-cooked diets. Six HCD recipes (2 highly digestible, 2 limited antigen, 2 low-fat) were formulated by 2 board-certified veterinary nutritionists to mimic the nutritional and ingredient profiles of veterinary CPDs for management of CCEs. The cost (in US$ on a per 100 kilocalorie [kcal] basis) of each recipe was determined via collection of ingredient prices from 3 grocery stores combined with supplement prices from online retailers. Prices of CPDs were obtained from a national online retailer. Maintenance energy requirements of 1.6 X (70 X BWkg0.75), where BWkg represents body weight in kilograms, were calculated for 3 dog sizes (5, 20, and 40 kg), and costs of feeding maintenance energy requirements with HCDs versus dry and canned CPDs were compared with a Kruskal-Wallis test and post hoc testing. The median costs of all dry and canned CPDs and HCDs were $0.29 (range, $0.18 to $0.46), $1.01 (range, $0.77 to $1.20), and $0.55 (range, $0.35 to $1.14), respectively. Feeding complete and balanced HCDs cost more than feeding dry CPDs (P < .001), but not canned CPDs (P > .99). Dry CPDs cost the least for nutritional management of CCEs. There is a wide range of costs for both CPDs and HCDs.

Environmental impact of diets for dogs and cats

Food production is responsible for almost one-quarter of the environmental impact and, therefore, its importance regarding sustainability should not be overlooked. The companion animal population is increasing, and an important part of pet food is composed of ingredients that have a high environmental impact. This study aimed to evaluate the impact of dry, wet, and homemade pet diets on greenhouse gas emission, land use, acidifying emission, eutrophying emissions, freshwater withdrawals, and stress-weighted water use. The wet diets were responsible for the highest impact, and dry diets were the type of diet that least impacted the environment, with a positive correlation between the metabolizable energy provided by animal ingredients and the environmental impact. It is necessary to consider the environmental impact of pet food since it is significant, and the population of pets tends to increase.

Research on Phosphorus Requirements in Red-Mini-Rock Hens Fed on Different Cereal-Based Diets

The aim of this paper was to determine the available phosphorus requirements in Red-Mini-Rock hens fed on wheat and maize-based diets combined with different levels of phosphorus supplemented in the form of mono- and dicalcium phosphate, based on the effect on the main properties of the eggs. Three diets based on wheat (50%) having three levels of phosphorus, 4.5, 3.0 and 1.5 g/100 g dry matter diet, respectively, and three diets based on maize (58%), with the same supplemented phosphorus levels were designed. Feed intake, laying performance and egg weight were not modified by feeding. The thickness and weight of the egg shell were higher (P˂0.05) in groups of hens fed on phosphorus supplemented levels of 3.3 and 4.4 g/100 g diet in both wheat-based and maize-based diets. Breaking strength of the eggshell was significantly higher (P˂0.05) in the groups of hens fed on maize-based diets supplemented 4.5 and 3.0% in phosphorus, respectively. The internal characteristics of the eggs were not significantly altered, excepting the color of the yolk, which showed a significantly higher reflectivity absorption capacity (P˂0.05) in the groups fed on maize-based diets.

Dietary calcium requirements of bighead carp (Aristichthys nobilis)

To investigate dietary calcium requirement of bighead carp (Aristichthys nobilis), six purified diets were formulated to contain different concentrations of calcium (0.09% (control), 0.43%, 0.76%, 1.12%, 1.44%, and 1.79% of dry diets). Each diet was hand-fed to triplicate 30 fish with an average initial body weight (3.31 ± 0.09 g) for 60 days. The results showed that weight gain (WG) and specific growth rate (SGR) significantly increased when dietary calcium level was from 0.09% to 0.76% (P &lt; 0.05). The phosphorus and calcium contents of whole fish body were highest in the 0.76% and 1.12% group, respectively (P &lt; 0.05). The serum phosphorus content in the 1.79% group was significantly lower than those in other groups (P &lt; 0.05). As dietary calcium content was from 0.09% to 0.76%, the activities of lipase and proteinase in the intestine had a significant increase (P &lt; 0.05), while the glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) activities were significantly decreased (P &lt; 0.05). Based on quadratic curve model analysis with WG and WGR as the appraising criteria, the appropriate dietary requirement of calcium for the bighead carp larvae (3.31 ± 0.09 g) was 1.01% - 1.02%.

Sucrose solution, but not liquid sucrose diet, leads to leptin resistance irrespective of the time of day that sucrose is available

Rats offered free access to sucrose solution in addition to a sucrose-free composite diet develop leptin resistance whereas those consuming a similar amount of sucrose from a dry diet remain leptin responsive. Here we tested whether rats consuming a complete high sucrose diet in liquid form also became leptin resistant. Female Sprague Dawley rats were offered a sucrose free diet (NS), a dry high sucrose diet (HS), NS diet plus 30% sucrose solution (LiqS), NS diet in liquid form (NSLiq) or HS diet in Liquid form (HSLiq). After 30 days LiqS rats were leptin resistant, but all other groups were leptin responsive even though HSLiq rats consumed as much sucrose as LiqS rats and NSLiq rats had the greatest amount of body fat. Therefore, development of leptin resistance is dependent upon the consumption of sucrose independent of any other nutrients. Because LiqS rats consume sucrose throughout the day and night we tested whether limiting sucrose solution access to either the light or dark period prevented development of leptin resistance. Leptin resistant LiqS rats were either given free access to sucrose, had access to sucrose only at night or had access only during the day. The intake of rats with limited access was supplemented to the level of those with free access by tube-feeding. The results of this study show that leptin resistance of LiqS rats is independent of when the sucrose is consumed and is unrelated to total energy intake, body fat mass or serum leptin concentration.

Rumen effects of monensin in dry cow diets varying in energy density.

Controversy has existed as to whether monensin will provide equal or differential benefits in a higher-energy, lower-roughage close-up diet versus a higher-roughage, lower-energy diet. Our objective was to determine the rumen effects of a controlled-energy, high-fiber diet balanced to meet but not greatly exceed energy requirements during the dry period or a traditional 2-group approach of higher-energy close-up diet. The effects of added monensin in each diet type were determined. Multiparous Holstein cows (n = 17) were fitted surgically with ruminal cannulas. During the first 4 wk of the dry period, all cows were fed a controlled-energy, high-fiber diet (CE) as a total mixed ration for ad libitum intake. During the last 3 wk before calving, half of the cows were switched to a higher-energy, close-up diet until calving (CU), whereas the other half continued to receive the CE diet. Within each dietary group, half of the cows received monensin (MON) supplementation in the diet (24.2 g/t of total dry matter) and half did not (CON). After calving, all cows received the same lactation diet containing monensin (15.4 g/t of dietary dry matter). At 14 d prepartum, dry matter intake was not different across treatments. The weight of rumen contents was greater for cows fed CE. Rumen liquid dilution rate, solids passage rate, pH, total volatile fatty acid (VFA) concentrations, molar proportions of acetate and propionate, and papillae length did not differ among diets. Butyrate percentage tended to be greater for cows fed CE. Postpartum, dry matter intake, mass of rumen contents, solids passage rate, pH, total VFA concentration, molar percentages of propionate and butyrate, and papillae length did not differ among treatments. Liquid dilution rate (16.6, 10.7, 16.0, and 18.2%/h for CE + CON, CE + MON, CU + CON, and CU + MON, respectively) was affected by a diet × monensin interaction. Cows on the CE + CON diet had a greater ruminal proportion of acetate than did cows fed CU + CON, whereas cows fed monensin on either diet were intermediate (diet × monensin interaction). Addition of MON to the CU diet decreased the proportion of propionate (diet × monensin interaction). Cows fed CE had greater mass of rumen contents before parturtition but the high inclusion of wheat straw in the CE diet did not negatively affect rumen papillae length. Monensin inclusion differentially affected liquid passage rate and VFA concentrations.

Dietary leucine supplementation improves growth performance, metabolic responses of liver via GCN2/ATF4, and insulin signaling pathways in largemouth bass (Micropterus salmoides).

An 8-week growth experiment was conducted to investigate the effects of dietary leucine on growth performance, body composition, and gene expression of hepatic nutrient metabolism in the largemouth bass (Micropterus salmoides). Six isonitrogenous (49.87%) diets with graded leucine levels (2.62, 3.07, 3.60, 3.87, 4.20, 4.71% of dry diet) were fed to triplicate groups with 20 juvenile fish (20.00 ± 0.13g). The results revealed that the specific growth rate (SGR) and weight gain (WG) increased significantly with increasing dietary leucine levels, reached their maximal value in the Leu-4.20% groups, and then decreased slightly. Although the feed conversion ratio (FCR) showed decreasing trends, no significant difference was detected. Leucine supplementation significantly improved the content of body protein and total plasma protein (TP). Additionally, a higher expression level of target of rapamycin (TOR) and ribosomal protein S6 (S6) mRNA was observed in the Leu-3.87% and Leu-4.20% diets, whereas the GCN2 (general control nonderepressible2 kinase) and AFT4 (activating transcription factor 4) mRNA expression levels were suppressed. The lipid content of the body was not influenced by leucine levels, whereas the content of total triglyceride (TG) first decreased significantly with increasing dietary leucine levels from 2.62 to 3.87% and then increased with increasing leucine levels (4.20% to 4.71%). The total cholesterol (TC) and low-density lipoproteins (LDL) trended in a similar direction but did not achieve statistical significance (P > 0.05). The expression of insulin receptor substrate 1 (IRS-1) was significantly elevated by dietary leucine levels, while protein kinase B (AKT) and phosphatidylinositol 3-kinase (PI3K) expression was inconsistently upregulated. Furthermore, leucine supplementation decreased plasma glucose and hepatic glycogen contents, and the expression levels of glucokinase (GK), phosphoenolpyruvate carboxykinase (PEPCK), and glucose-6-phosphatase (G6pase) were significantly inhibited at 4.20% and 4.71% leucine diets. Analyses of the change in SGR and FCR using the quadratic regression model estimated that the optimum dietary leucine requirement of juvenile largemouth bass was 4.42% and 4.63% of the dry diet (8.86% and 9.28% of dietary protein), respectively.

Morpho-Histological Studies of the Gastrointestinal Tract of the Orange-Rumped Agouti (Dasyprocta leporina Linnaeus, 1758), with Special Reference to Morphometry and Histometry.

The morphology of the gastrointestinal tract (GI) is a strong indicator of a species' dietary habits. The objective of this study was to describe and quantitatively analyze the gross and microanatomy of the digestive tract of the orange/red-rumped agouti (Dasyprocta leporina) and relate it to the feeding habits of this animal. The digestive tracts of six adult males were used for this study. The results showed that the esophagus was thick (mean thickness of 1023.78 ± 28.97 μm) and lined by keratinized epithelium with scant esophageal glands. Mucosa-associated lymphocytic infiltration was robust throughout the GI tract. These findings suggest that the esophagus was well adapted to a coarse diet. The simple stomach with well-developed gastric glands in the fundus region (mean thickness of 605.39 ± 28.68 μm) was indicative of an adaptation to a carnivorous diet. The small intestine constituted approximately 80% of the length of the GI tract. The remarkable development of the jejunum with a greater villus length (mean thickness of 182.50 ± 27.38 μm) indicated a greater absorptive capacity in frugivorous and carnivorous diets. The long cecum and well-developed colon clearly indicated that the GI tract was well adapted to frugivorous and herbivorous diets. Overall, D. leporina showed that it is well adapted to an omnivorous diet. These results suggest that D. leporina can be fed a balanced omnivorous dry diet with a high protein content of plant or animal origin that is well suited to the architecture of the GI tract in captivity.

Effects of dietary pyrroloquinoline quinone on growth performance, serum biochemical parameters, antioxidant status, and growth-related genes expressions in juvenile yellow catfish, Pelteobagrus fulvidraco

This study aimed to evaluate the impacts of dietary pyrroloquinoline quinone (PQQ) supplement on growth performance, serum biochemical parameters, antioxidant status, and growth-related genes expressions in juvenile yellow catfish, Pelteobagrus fulvidraco. Triplicate groups of fish (n = 40) with an average weight of 5 g were fed with five gradient levels PQQ-incorporated diets (0 (basal), 1.5 mg/kg; 3.0 mg/kg; 4.5 mg/kg, 6.0 mg/kg) for 56 days. Our findings revealed that fish fed with the diets containing PQQ at the level of 3.0-6.0 mg/kg showed significantly higher final body weight, weight gain rate, and specific growth rate than those of that in the control group (P &amp;lt; 0.05). The activities of protease were observed significantly increased in fish fed with diets containing 4.5 mg/kg and 6 mg/kg PQQ (P &amp;lt; 0.05). Meanwhile, fish in 4.5 mg/kg PQQ group showed significantly lower levels of serum total cholesterol, triglycerides, and low-density lipoprotein cholesterol, and significantly higher level of the high-density lipoprotein cholesterol (P &amp;lt; 0.05). The antioxidant-related parameters of superoxide dismutase and total antioxidant capacity were markedly elevated (P &amp;lt; 0.05), while malondialdehyde content was significantly reduced in 3.0-6.0 mg/kg PQQ group (P &amp;lt; 0.05). Meanwhile, the mRNA expression levels of growth-related genes (growth hormone, insulin-like growth factor 1, and insulin-like growth factor 2) were dramatically up-regulated in the liver of fish fed with the diets containing 3-6 mg/kg PQQ in comparison with the control group (P &amp;lt; 0.05). In conclusion, dietary PQQ could improve the growth performance, serum biochemical parameters, antioxidant status, and growth-related genes expressions in juvenile yellow catfish, and the optimal dietary PQQ level was evaluated to be 4.92 mg/kg of dry diet for juvenile yellow catfish.

Amelioration of obesity-related metabolic disorders via supplementation of Caulerpa lentillifera in rats fed with a high-fat and high-cholesterol diet.

Dietary modification, including functional foods, could reduce comorbidities due to obesity. An increase in serum glucose and lipids is often seen in obesity. Furthermore, obesity is also characterized by a decrease in antioxidant capacity (i.e., decrease in superoxide dismutase/SOD) and downregulation of peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α). It has been well established that PGC-1α is important to regulate mitochondrial biogenesis. Sea grapes (Caulerpa lentillifera) are known as a traditional food in many Asia-Pacific countries. Recent evidence suggests that sea grapes have many beneficial properties as functional foods and may have potential therapeutic functions. We investigated the effect of sea grapes (C. lentillifera) on serum glucose, lipids, PGC-1α, and protein levels of SOD in the liver of Rattus norvegicus, which is induced with a high-fat and high-cholesterol diet. A total of four groups were made, each containing ten male Rattus norvegicus; group A received a standard dry pellet diet as control, group B received cholesterol- and fat-enriched diets (CFED), groups C and D received CFED and 150 and 450 mg/kg body weight (BW) of sea grape extract, respectively, for 4 weeks. Serum glucose and cholesterol were assessed using a blood auto-analyzer. Serum PGC-1α was measured using ELISA. SOD levels were calculated using the superoxide dismutase assay kit by Sigma-Aldrich with blood taken from liver tissue. In this study, sea grape extracts improved total cholesterol levels better than the CFED and normal groups. The efficacy of total cholesterol improvement was similar between the two doses of sea grape extract. Furthermore, sea grape extract increased PCG-1α levels, especially with the dose of 150 mg/kg BW. Blood glucose was also lower in the groups of sea grape extract. Interestingly, the groups treated with sea grapes extract exhibited higher levels of liver SOD compared to the normal and CFED groups. To conclude, sea grapes (C. lentillifera) have promising potential for anti-hyperglycemia and anti-hypercholesterolemia, and for reducing oxidative stress, and providing various health benefits for metabolic disorders.

Effect of Supplementation of Vitamin A on Growth, Haemato-Biochemical Composition, and Antioxidant Ability in Cyprinus carpio var. communis.

Vitamin A requirement in fingerling common carp, Cyprinus carpio var. communis (1.64 ± 0.02 g; ABW ± SD), was evaluated by conducting a 10 week growth experiment. Casein-gelatin-based test diets representing six graded levels of vitamin A (0, 0.03, 0.07, 0.11, 0.15, and 0.19 g/kg, dry diet) were designed and fed to the triplicate group of fish at 08:00 and 16:00 hrs at the rate of 4% body weight per day. Growth parameters like live weight gain (LWG %), feed conversion ratio (FCR), protein efficiency ratio (PER), specific growth rate (SGR), and body protein deposition (BPD) improved significantly (P < 0.05) with each elevated dietary vitamin A level and found maximum growth rate along with the best- FCR at 0.11 g/kg diet. Dietary vitamin A levels also significantly (P < 0.05) affected haematological parameters of the fish. Highest haemoglobin (Hb), erythrocyte count (RBC), haematocrit content (Hct %), and lowest leucocyte count (WBC) were observed at 0.11 g/kg vitamin A fed diet compared to all the diets. Highest protein and lowest fat content were observed in the group of fingerlings fed with 0.11 g/kg vitamin A containing diet. Blood and serum profile also showed some significant (P < 0.05) differences with elevating concentration of dietary vitamin A levels. Serum parameters like aspartate aminotransferase (AST), alanine aminotransferase (ALT), and cholesterol values decreased significantly (P < 0.05) at 0.11 g/kg vitamin A fed diet compared to control diet. However, except albumin the other electrolytes improved significantly (P < 0.05) and maximal values of these parameters were also evident at 0.11 g/kg of vitamin A fed diet. Better value of TBARS was found in the group that fed 0.11 g/kg vitamin A diet. Hepatosomatic index and condition factor improved significantly (P < 0.05) with fish fed at optimal dose 0.11 g/kg of vitamin A diet. Based on quadratic regression analysis of LWG%, FCR, BPD, Hb, and calcium values of C. carpio var. communis against the varying levels of dietary vitamin A, an optimum growth, best FCR, higher BPD, Hb, and Ca values lie in the range of 0.10 to 0.12 g/kg diet, respectively. The data generated during this study would be important in developing vitamin A balanced feed for successful intensive culture of C. carpio var. communis.

Proportions of concentrate and rehydrated ground grain corn silage at different storage times for better use of starch by lambs

This study aimed to evaluate the nutritional and bioeconomic potential of rehydrated ground grain corn silage (RGGCS), at different storage times associated with proportions of concentrates for better starch utilization by lambs. Forty Dorper-Santa Inês crossbred lambs were used, with an average body weight of 24 ± 3.9kg, and an average age of 90days. The lambs were feedlot for 63days in experiment design completely randomized, with eight repetitions and five experimental diets: Diet 1: 850g/kg concentrate including dry ground corn; diet 2: 850g/kg concentrate including RGGCS ensiled for 45days; diet 3: 650g/kg concentrate including RGGCS ensiled for 90days; diet 4: 650g/kg concentrate including RGGCS ensiled for 45days; diet 5: 850g/kg concentrate including RGGCS ensiled for 45days. As roughage, silage corn whole plant. Starch intake was higher (P < 0.05) with the dry ground corn diet; however, digestibility was lower (P < 0.05) for most nutrients compared to the RGGCS diet. A smaller amount of starch in the feces of animals that received the RGGCS diet was found. A diet with 850g/kg of concentrate, including RGGCS ensiled for 45days, generates higher net income, increases nutrient intake, and could be an alternative during the fluctuation of corn prices.

Effects of a whole food diet on immune function and inflammatory phenotype in healthy dogs: A randomized, open-labeled, cross-over clinical trial.

Whole foods in humans decrease inflammation and risk for various diseases, as well as increase weight loss and immune function. Nutrition has been shown to be an integral component in the management of various diseases in dogs but the immunologic and anti-inflammatory effects of whole food diets have not been explored. Therefore, our objective was to assess the effect of feeding a whole food diet on immune function and inflammatory phenotype in healthy dogs. A prospective, randomized, open-labeled, cross-over clinical trial was performed. Sixteen healthy client-owned dogs were fed either a whole food or an extruded dry diet, and after 67 days, they were fed the alternate diet for an additional 67 days. Blood samples were obtained at the completion of each treatment arm (i.e., days 67 and 134). Serum c-reactive protein (CRP), haptoglobin (Hp), and serum amyloid-A (SAA) were measured with ELISA assays. Whole blood cultures were performed with exposure to a phosphate-buffered solution (PBS), lipopolysaccharide (LPS), and lipoteichoic acid (LTA). A canine specific multiplex bead-based assay was then used to measure tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-10, granulocyte-macrophage colony-stimulating factor (GM-CSF), IL-2, IL-8, and monocyte chemoattractant protein (MCP)-1 concentrations. Granulocyte/monocyte (GM) phagocytosis and oxidative burst associated with Escherichia coli were evaluated via flow cytometry. Dogs fed a whole food diet had significantly lower TNF-α-to-IL-10 ratios (P = 0.05) and higher production of IL-8 (P = 0.03) with LTA-exposed leukocytes compared to dogs fed an extruded dry diet. There were no between-treatment differences in the remaining leukocyte cytokine responses, serum CRP, Hp, SAA concentrations, or GM phagocytic and oxidative burst capacities. Whole food diets could have immunomodulatory effects in dogs. Future studies in non-healthy dogs are warranted.

Dietary tryptophan requirement of fingerling Channa punctatus (Bloch) based on growth, hematological parameters, intestinal enzymes, non-specific immune response, and antioxidant capacity

In this investigation, the tryptophan requirement of C. punctatus fingerling (5.45 ± 0.07 g) was determined by feeding seven isoproteic (450 g kg−1 CP) and isoenergetic (14.7 kJ g−1 DE) diets with graded levels of tryptophan 1, 2, 3, 4, 5, 6, and 10 g kg−1, respectively to randomly stocked groups in triplicate at 8:00, 12:30 and 17:30 h near to satiety for 12 weeks. Tryptophan contributed by casein and gelatin in basal diet was 1 g. To attain the desired tryptophan levels 0, 1, 2, 3, 4, 5 and 9 g kg−1 crystalline tryptophan was added to basal diet. The analyzed value of tryptophan in the experimental diets was found to be 0.9, 1.5, 2.6, 3.3, 4.7, 5.4 and 9.1 g kg−1, and were designated as Tr0.9, Tr1.5, Tr2.6, Tr3.3, Tr4.7, Tr5.4 and Tr9.1. Significant enhancement (P < 0.05) was found in Absolute weight gain (AWG), specific growth rate (SGR), protein retention efficiency (PRE), protein gain (PG), and RNA/DNA ratio with increasing tryptophan content up to 4.7 g kg−1 dry diet. Carcass protein and fat also improved significantly up to 4.7 g kg−1 tryptophan content. Hematological indices such as hematocrit, hemoglobin, red blood cell counts, erythrocyte sedimentation rate were positively affected (P < 0.05) up to 4.7 g kg−1 tryptophan content of the diet. Serum protein, glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT), and lysozyme were also positively correlated (P < 0.05) up to 4.7 g kg−1 dietary tryptophan content while malondialdehyde (MDA), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) showed the inverse pattern. On subjecting the AWG, FCR, PRE, PG, RNA/DNA ratio, Hb and SOD against dietary tryptophan content to quadratic regression analysis, the tryptophan requirement was found at 5.43, 5.5, 5.21, 4.96, 4.81, 4.85 and 5.39 g kg−1 diet, respectively. Based on the parameters mentioned above, the addition of tryptophan in feed in the range of 4.81–5.5 g kg−1 is recommended for formulating tryptophan balanced, practical feeds for this fish.

Performance of Holstein calves receiving equal solids per day from high-solids milk and milk replacer blend once or twice daily combined with dry versus wet fine-particle starter diet

This study examined the effects of frequency of feeding high-solids milk and milk replacer (MMR) blend combined with dry matter (DM) content of starter feed on the performance of dairy calves. Forty-eight Holstein calves (40.2 ± 3.33 kg of body weight) were randomly assigned to 1 of 4 treatments in a completely randomized design. Based on a combination of 2 MMR feeding frequencies (once versus twice daily) and 2 starter DM levels (91.1 and 50% DM), 4 treatments were designed as (1) once daily + dry starter feed (OD), (2) once daily + wet starter feed (OW), (3) twice daily + dry starter feed (TD), and (4) twice daily + wet starter feed (TW). The amount of milk replacer powder added to whole milk was adjusted at each feeding frequency to ensure that calves received similar solids from the MMR blend via the twice-daily (total solids = 18.6%) or once-daily (total solids = 31.0%) programs. Starter intake in the preweaning period did not differ between treatments (average 0.39 kg of DM/d), but the postweaning starter intake was greater in calves fed the wet starter (OW and TW) than in those fed the dry starter (OD and TD). Calves receiving the high-solids MMR blend twice versus once daily grew faster before weaning, which was reflected by a greater weaning weight in the TD and TW groups (88.9 kg) than in the OD and OW groups (83.2 kg). The daily growth rate after weaning did not differ between treatments and averaged 1.15 kg/d. Gain-to-feed ratio during the preweaning period was greater in calves from TD and TW (mean 0.67) than in calves from the OD or OW groups (mean 0.58). Postweaning gain-to-feed ratio was not different among treatments and averaged 0.38. Days to first diarrhea and duration of diarrhea (4.66 ± 0.38), as well as days that animals were treated with antibiotics, remained unaffected with treatments. Although preweaning body weight gain was lower with once-daily milk feeding, calves were twice as heavy at weaning as at birth in both milk feeding programs regardless of starter moisture content, which may qualify the once-daily milk feeding program as a cost-effective management strategy in commercial calf-rearing operations. Feeding solutions with a high solids content (above 15%) may be associated with an increased risk of abomasal bloat and should be used with caution.

Nutritional Content of Adult Norway Rats for Small Carnivores’ Feeding

Rats are the natural diet of many free-ranging carnivores. They are also fed to small carnivore mammals, raptor birds, and reptiles in captivity as a sole or partial diet, however, little is known about the nutrients that a rat can provide as animal feed. This study aimed to determine the nutritional content of the whole captive-bred Norway rats. A total of 12 randomly selected weaned male and female Wistar Norway rats were fed ad libitum with a local dry dog food diet. The rats were weighed weekly until an average weight of 300 g was reached. Biochemical and mineral analyses were carried out for each rat. The results of the study showed significant differences between male and female rats in terms of growth rate, crude protein, total fat, and calcium concentrations. Males presented a faster growth rate and reached the desired weight in around half the time (6 weeks), compared to females (13 weeks). Moreover, males had a higher percentage of crude protein (23.57%) on a fed matter basis, calcium (2.61%), and phosphorus (0.98%). Females showed higher total fat (13.92%) and lower crude protein (19.49%), calcium (0.54%), and phosphorus (0.47%), compared to males. The results of this research may be used to determine whether a whole rat can provide all the necessary nutrients to carnivore animals commonly kept in captivity. Present findings indicated that rats could provide the necessary nutrients, however, if given as a sole diet, they could not be enough to supply the nutritional requirements of animals in the long term.

Dietary threonine requirement of fingerling Channa punctatus (Bloch) based on growth, feed conversion, protein retention efficiency, hematological parameters, and biochemical composition

Six isonitrogenous and isocaloric purified diets with different threonine concentrations (5, 10, 15, 20, 25, and 30 g kg−1) were fed to triplicate groups of Channa punctatus (6.24 ± 0.07 g) for 12 weeks to estimate dietary threonine requirement. Absolute weight gain, protein and threonine retention efficiency, feed conversion ratio and RNA/DNA ratio of trial diets with incremental threonine concentrations improved up to 20 g kg−1 dry diet. Carcass protein and moisture contents increased up to 20 g kg−1 dietary threonine. However, carcass fat also showed a reverse pattern, increasing threonine concentrations up to a 20 g kg−1 dry diet. Hemoglobin (Hb), red blood corpuscles (RBCs) and hematocrit (Hct) value improved significantly (p < .05) up to 20 g kg−1. Total serum protein, superoxide dismutase (SOD), catalase (CAT), and lysozyme was found to increase significantly up to 20 g kg−1 dry diet, and a significant fall was recorded at a higher threonine level (Th30). Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) concentrations declined significantly with dietary threonine levels up to 20 g kg−1. Quadratic regression analysis of absolute weight gain, feed conversion ratio, protein, and threonine retention efficiency data against incremental threonine levels projected the optimum requirement between 22.2 and 23.0 g kg−1 dry diets.

Dietary Arginine Modulates Growth Performance, Hemato-Biochemical Indices, Intestinal Enzymes, Antioxidant Ability and Gene Expression of TOR and 4E-BP1 in Rainbow Trout, Oncorhynchus mykiss Fingerlings

We evaluated the effect of arginine on growth, hemato-biochemical variables, intestinal enzymes, antioxidant ability, and expression of target of rapamycin (TOR) signaling pathway related genes in fingerling Oncorhynchus mykiss. A series of six uniform diets consisting of 450 g kg-1 of protein and 20.9 g-1 of energy with graduated levels (10.0, 12.5, 15.0, 17.5, 20.0, and 22.5 g kg-1) of arginine were formulated. Significant (p &amp;lt; 0.05) variations were observed in various analyzed parameters. Growth parameters showed a positive linear trend with increasing arginine levels up to 17.5 g kg-1. Fish offered 17.5 g kg-1 of dietary arginine exhibited highest body protein, lowest moisture, and intermediate fat contents, whereas, body ash content did not significantly (p &amp;gt; 0.05) change with respect to each dietary arginine offered diet, except for the lowest levels. Each group also produced significant (p &amp;lt; 0.05) changes in their hematological variables with maximum hemoglobin (Hb), hematocrit (Hct) content, and red blood cell (RBC) count noted at 17.5 g kg-1 arginine diet. Although the majority of blood plasma parameters were insignificantly (p &amp;gt; 0.05) different with respect to varied arginine fed diets, plasma aspartate transaminase (AST) showed significant (p &amp;lt; 0.05) variations across the treatments. Moreover, total protein, alkaline phosphatase (ALP) and albumin contents increased significantly (p &amp;lt; 0.05) with increasing arginine concentrations up to 17.5 g kg-1 and, thereafter, a declined trend in these parameters were noted. Intestinal enzymes and antioxidant properties showed significant (p &amp;lt; 0.05) variations, except plasma amylase, which showed insignificant variation. The maximum up-regulation of TOR and 4E-BP1 gene expression levels were found for fish fed 17.5 g kg-1 of dietary arginine compared to the lower (10.0 and 12.5 g kg-1) and higher (20.0 and 22.5 g kg-1) arginine levels, which indicates that fish utilize arginine more efficiently at this point. Quadratic regression analysis of live weight gain (LWG), feed conversion ratio (FCR), protein efficiency ratio (PER) and body protein deposition (BPD) indicated the optimal arginine requirement of rainbow trout to be 17.61 g kg-1 of dry diet, corresponding to 39.13 g kg-1 of dietary protein, which enhances growth, immunity, antioxidant ability, and also promote TOR signaling pathway in rainbow trout.