Test Diets Research Articles

Higher intake of β-glucan impairs reproduction in a female teleost, Tor putitora (Hamilton, 1822).

Although the immuno-modulatory and stress-relieving properties of β-glucan is well elucidated in humans and other animal models, including fish, its role as a dietary supplement on reproduction is extremely scarce. Therefore, in this study, adult female fish were fed one of four test diets having 0 (control), 0.5, 1, and 1.5% β-D-glucan for 130 days and its effect on reproductive performance, ovarian and liver histology, sex hormones, and transcript abundance of selected reproduction-related genes was assessed. Low dietary intake of β-glucan improved fertilization and hatching rates (p<0.05). The relative fecundity and percentage of spawning females were higher (non-significant) in 0.5% β-glucan-fed groups. Surprisingly, even after 130 days, spawning did not occur in 1.5% β-glucan-fed individuals. Irrespective of β-glucan intake, all the brooders recorded similar plasma 17β-estradiol and maturation-inducing hormone (p>0.05). Higher intake of β-glucan (1.5%) upregulated aromatase genes without a parallel increase in 17β-estradiol. However, plasma vitellogenin increased with increasing β-glucan up to 1.0% then declined at 1.5% (p<0.05). The fish that received control, 0.5, and 1.5% β-glucan recorded similar vitellogenin levels in their plasma. Significantly higher plasma cortisol was evidenced in 1.5% β-glucan fed brooders (p<0.05). Histologically, higher follicular atresia and leaking of yolk material was evidenced in 1.5% β-glucan-fed group. Liver histology revealed the highest nutrient/lipid accumulation in fish that received 1.0% and 1.5% β-glucan. This study demonstrated the stimulatory effect of β-glucan intake at a lower dose (0.5%) on reproduction. However, higher intake (1.5%) could perturb normal reproductive function in a fish model and caused an increased number of atretic follicles leading to spawning/reproductive failure.

Mitigating Aflatoxin B1-Induced Growth Impairment and Hepatic Stress in Nile Tilapia (Oreochromis niloticus): Comparative Efficacy of Saccharomyces cerevisiae and Silicate-Based Detoxifiers.

The objective of this study was to detect the effects of acute aflatoxin B1 (AFB1) exposure in Nile tilapia (Oreochromis niloticus) and the effectiveness of Saccharomyces cerevisiae and silicate in reducing these effects. Two hundred and forty Nile tilapia fingerlings (16 ± 0.5g) were randomly assigned to four experimental groups, each with 60 fish and three replicates. Control basal diet (Diet 1) and three test diets were formulated, where Diet 2 was supplemented with 200ppb AFB1. Diets 3 and 4 were intoxicated with AFB1 (200ppb) and supplemented with 0.5% S. cerevisiae or 0.5%, respectively. After 60days, Diet 1 had considerably greater growth characteristics than the other groups (p < 0.05). Diet 2 revealed a reduced (p < 0.05) survival rate after 1month of exposure. In addition, Diet 1 showed higher (p < 0.05) total protein and albumin levels than Diets 3 and 4. AFB1 residues were detected in the liver in fish-fed Diet 2, Diet 4, and Diet 3. Alanine aminotransferase, aspartate aminotransferase, creatinine, and urea levels increased (p < 0.05) in fish-fed Diet 2. The glutathione peroxidase, lysozyme, and catalase activity were decreased (p < 0.05) in the fish-fed Diet 2. The malondialdehyde level was significantly higher in fish given Diet 2 (p < 0.05) than in fish-fed Diets 3 and 4. Histopathological investigation of fish-fed Diet 2 revealed impaired liver and spleen; however, both treatments (Diets 3 and 4) successfully lowered inflammation and preserved liver and spleen integrities. In conclusion, AFB1 impaired growth performance and posed a severe health risk to Nile tilapia. Furthermore, S. cerevisiae alleviated the contamination of AFB1 effects more efficiently than silicate employed for toxin adsorption.

Effects of quercetin and hydroxytyrosol supplementation in a high-fat diet on growth, lipid metabolism, and mitochondrial function in spotted seabass (Lateolabrax maculatus)

Endoplasmic reticulum (ER) stress and mitochondrial impairment commonly occur during the progression of fatty liver disease. There is a close connection and crosstalk between mitochondria and ER. The potential positive influence of mitigating ER stress (ERS) and mitochondrial damage in the context of preventing and treating fatty liver was explored in spotted seabass (Lateolabrax maculatus) as a susceptible model to fatty liver. A normal-fat diet (11% fat, NFD) and a high-fat diet (17% fat, HFD) were formulated and three additional diets were prepared by supplementation of quercetin (QUE) (0.1%), hydroxytyrosol (HT) (0.02%) or their combination (0.1% QUE + 0.02% HT) to the HFD (HFD + QUE HFD + HT and HFD + QUE + HT diets).Three replicate groups of fish (25 ± 0.02 g) were fed the test diets to visual satiety for 8 weeks. The results revealed the deterioration of growth, feed intake and feed utilization in HFD group compared to the NFD group whereas QUE and HT application improved their values and the optimum results were achieved for the HFD + QUE + HT group. Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities, and both serum and hepatic triglyceride (TG), total cholesterol (T-CHO) and non-esterified free fatty acids (NEFA) concentrations were enhanced in HFD group, and their values decreased by QUE and HT, particularly their combined supplementation. The results of oil red O staining exhibited a remarkable reduction in number of lipid droplets in the liver of fish from HFD + QUE + HT group compared to the HFD group. Whole-body and muscle fat contents and abdominal fat index decreased by QUE and HT application. Expression of lipid metabolism related genes (srebp-1c, fas, acc) were down-regulated by QUE and HT treatment. Co-supplementation of QUE and HT down-regulated the expression of ERS-related genes (grp78, chop, perk, atf6, ire1), improved ER ultrastructure, and enhanced the coupling between mitochondria and ER. Moreover, expression of genes associated with hepatic mitochondrial biogenesis (pgc1-α, pgc1-β, nrf1) and mitophagy (pink1, atg5, mul1) was up-regulated in HFD + QUE, HFD + HT and HFD + QUE + HT groups. These data suggest that combined supplementation of QUE and HT in HFD for spotted seabass can improve growth and feed utilization, reduce hepatic damage and fat accumulation, and alleviate HFD induced ERS and mitochondrial dysfunction.

Duckweed protein as an alternative plant-based protein source for dog and cat dry diets.

Duckweed has attracted increasing attention as a high-quality and sustainable novel plant-based protein source. However, little research has been conducted in dogs and cats. We evaluated the effects of inclusion of duckweed protein (Lemna; MCSelect; Parabel; Vero Beach, FL) primarily in replacement of pea protein in dog diets at 0%, 5%, and 10% and cat diets at %, 10%, and 15% on stool quality, nutrient digestibility, and palatability. We hypothesized that duckweed protein would be a viable protein source in both dog and cat diets by showing no detriment to nutritional outcomes. All feeding tests were conducted at an independent research facility (Susquehanna, PA). A standard 2-bowl palatability test over a 2-d period was conducted with adult animals (n = 30 each) to determine intake ratio between test diets (duckweed-containing diets) and control diets (0% duckweed protein). Apparent total tract nutrient digestibility was conducted with 18 adult dogs and 21 adult cats (n = 6 to 7 per diet) with 5 d of diet acclimation followed by 5 d of total fecal collection. Stool quality was evaluated on a 1 to 5 scale where 1 = non-formed or diarrhea and 5 = hard, formed. Palatability data were analyzed using paired t-test (daily consumption) and chi-square test (first choice). All other data were analyzed by ANOVA and contrast (SAS version 9.4). For cats, 10% duckweed had greater (P < 0.05) palatability than control, while no difference was observed between 15% duckweed protein and control. For dogs, 5% and 10% duckweed protein had (P < 0.05) lower palatability, demonstrating a preference to control. Both cats and dogs fed duckweed diets had acceptable stool quality (Mean = 3.4 and 3.3, respectively). No detriments in nutrient digestibility were observed in dogs fed 5% and 10% duckweed protein; however, cats fed 10% and 15% duckweed protein had (P < 0.05) lower dry matter, protein, and energy digestibility vs. control. In conclusion, the data collected indicate that duckweed can be a viable replacement for other plant-based proteins in dog diets at inclusion levels up to 10%; more development is needed for duckweed protein inclusion into cat diets.

Inorganic Phosphorus Supplementation in Diets for Farmed Shrimp: Performance and Digestibility of Juvenile Litopenaeus vannamei Fed Monosodium Phosphate, Monoammonium Phosphate, Magnesium Phosphate, and Monocalcium Phosphate

Inorganic phosphates have been used in shrimp feeds to meet phosphorus (P) needs, which may be quantitatively affected by the dietary content of P and other minerals and digestibility. In the present study, performance and digestibility were determined simultaneously in juvenile shrimp (Litopenaeus vannamei) during the grow‐out period (4–23 g ind wt). Shrimps were fed plant‐based diets supplemented with different phosphate ingredients: monosodium phosphate (MSP), monoammonium phosphate (MAP), magnesium phosphate (MgP), and monocalcium phosphate (MCP). The total P level in test diets was 0.79%. MSP supplementation was tested at two dietary calcium:phosphorus ratios to check for possible effects upon shrimp performance and digestibility. A negative control diet was tested with a similar formulation without inorganic phosphate supplementation (0.47% total P). Shrimp was reared in a recirculated clear water tank system (35 ppt salinity, 30°C, 100 individuals/m3) with continuous feeding provided by automatic pellet delivery. Feces were sampled 4–5 times daily throughout the trial. A negative control diet produced P limitation and significantly reduced shrimp performances compared to P‐supplemented diets (P &lt; 0.05). Performance of shrimp‐fed diets containing inorganic phosphates varied for feed conversion rate: 1.24–1.34, survival: 87%–94%, growth: 2.50–2.59 g/week, and no significant difference was found among dietary treatments (P &gt; 0.05). Inorganic P supplementation resulted in significantly higher dry matter, crude protein, ash, and P apparent digestibility coefficient (ADC) compared to P limited negative control diet (P &lt; 0.05). In addition, reduced P ADC (P &lt; 0.05) was checked with higher dietary Ca:P ratio. Phosphorus digestibility in test diets showed significant differences: MSP &gt; MCP, MgP, and MSP + CaCO3; MAP &gt; MSP + CaCO3 (P &lt; 0.05). Digestible P (%) could then be calculated in test diets: MgP (4.77 g Pdig/kg of feed), MSP + CaCO3 (4.81 g Pdig/kg of feed), MCP (5.0 g Pdig/kg of feed), MAP (5.13 g Pdig/kg of feed), and MSP (5.30 g Pdig/kg of feed). Digestible P in phosphate sources (%) could then be calculated: 88.2% MSP, 84.2% MAP, 79% MCP, 72.2% MgP, and 71.8% MSP + CaCO3. Shrimp whole body and exoskeleton phosphorus content also showed significantly higher values in P‐supplemented diets compared to control, regardless of the source tested (P &lt; 0.05). It is concluded that tested phosphates were suitable for feeding juvenile shrimp with MSP, MAP, and MgP diets showing high feed efficiency, while MSP and MAP diets resulted in numerically increased growth, coinciding with numerically higher P digestibility in these phosphates. The elevated P digestibility in the phosphates seems related to their water solubility, though MgP, less soluble and digestible in comparison to MSP and MAP, could also produce good performance.

GROWTH PERFORMANCE, NUTRIENT DIGESTIBILITY AND HAEMATOLOGICAL INDICES OF BROILER CHICKENS FED DIETS CONTAINING BIODEGRADED SWEET ORANGE (CITRUS SINENSIS) PEEL MEAL AS REPLACEMENT FOR MAIZE

A 56-days feeding trial was conducted to determine the effect of using the biodegradation sweet orange peel meal (BSOPM) as a replacement of maize in diet on growth performance, nutrient digestibility and haematological parameters of broiler chicks. A total of 180, one-day old broilers were distributed equally into six dietary treatments with 3 replicate of 10 chicks in each in a completely randomized design. The biodegraded sweet orange peel meal (BSOPM) was used to replaced maize at 0, 5, 10, 15, 20, and 25% of the control diet (T0) and five test diets (T5) (T10) (T5) (T20) and (T25) in finishers broilers diets. Laboratory analyses were carried out on the BSOMP and experimental diets to determine its proximate composition and the result revealed that, BSOPM contained metabolizable energy content of 2854.24 kcal/kg and 89.60% dry matter (DM), 7.58% crude protein (CP), 11.11 % crude fibre (CF), 2.89% ether extract (EE), 11.58% total ash (TA), 66.84% nitrogen free extract (NFE). Results also showed that average final live body weight ranged from 798.68 – 1582.64g. Average daily feed intake and feed conversion ratio were significantly (p˂0.05) affected across the dietary treatments while final weight gain, average daily weight gain and mortality were not significantly (p&gt;0.05) affected across the dietary treatments. The results of haematological and serum biochemical indices showed that, there were no significant differences (p&gt;0.05) except for mean corpuscular volume (MCV) indicating that no physiological abnormalities resulted from the feeding of BSOPM to broiler chicken.

Valor nutritivo das folhas secas de Cratylia argentea na alimentação de coelhos em crescimento

Abstract Nutrition in rabbit farming accounts for about 70% of all costs; in this sense, C. argentea is an excellent alternative as a feed, due to its bromatological composition. Our goal is to evaluate the nutritional value of diets formulated with the dried leaves of C. argentea to feed growing rabbits. Twenty-eight white rabbits of the New Zealand breed, 55 days old, of both sexes, were used. Two treatments (n = 14, 7 males, and 7 females) were evaluated in a randomized block experimental design in a 2 x 2 factorial scheme. The control diet (CTRL) was formulated to meet the nutritional requirements of growing rabbits, and the test diet (DRY) was obtained by replacing 20% of the CTRL diet with dried leaves of C. argentea. The experimental period was comprised of 11 days, with seven days of adaptation and four days of total feces collection. The average daily gain, dry matter intake, feed conversion, and final body weight were not affected by replacing the CTRL diet with the dried leaves of C. argentea. The coefficient of dry matter digestibility showed better results in CTRL rabbits (female: 72.19%, male: 72.48%). Rabbits fed with the CTRL diet exhibited a higher consumption of crude protein compared to those fed with the DRY diet, however, these rabbits showed higher elimination and lower retention of crude protein. It is concluded that C. argentea presents values of 1,400.67 kcal per kg of dry matter, digestible energy, and 3.34% digestible protein per kg of dry matter.

Effect of different levels of whole corn germ on energy values and ileal digestibility in broilers.

This study evaluated the effects of broiler age (A) and levels of replacement (L) of control diet (CD) on the utilization of energy and nutrients of whole corn germ. 720 one-day-old broilers (b) were allocated at completely randomized design to six treatments and six replicates, in three assays: pre-starter (1-8 days, 10 b/cage), starter (15-22 days, 6 b/cage), and grower (28-35 days, 4 b/cage) phases. The treatments were: CD and four test diets (L): 100, 150, 200, 250, or 300 g kg-1 of the CD replaced by WCG levels. The data were adjusted to the response surface model. The stationary points for apparent energy metabolizable (AME) and AME corrected for nitrogen balance (AMEn) were: 4173 and 3591 kcal kg-1, respectively, and coefficients of gross energy (AMCGE), crude protein (AMCCP), dry matter (AMCDM), and ether extract (AMCEE) were: 49.3, 40.4, 72.6, and 61.3%, respectively; and Ileal digestibility coefficient of crude protein (IDCCP), dry matter (IDCDM), digestibility crude protein values (DCP), and digestibility dry matter value (DDM) were: 78.0, 57.96, 8.50, and 56.17%, respectively. The EP for AMEn was at 18 days of age, 28 g kg-1 WCG. There was a correlation between A and L on digestibility and metabolisability of nutrient's WCG.

Combined Effects of Yellow Mealworm (Tenebrio molitor) and Saccharomyces cerevisiae on the Growth Performance, Feed Utilization Intestinal Health, and Blood Biomarkers of Nile Tilapia (Oreochromis niloticus) Fed Fish Meal-Free Diets.

Aquafeed quality is the most critical factor for aquaculture sustainability. However, limitations of traditional feed ingredients such as fishmeal (FM) need alternative strategies to ensure the nutritional requirements for aquatic animals. In this trial, four test diets were formulated (2 × 2 factorial design), where FM was incorporated in two diets at 10% with or without Saccharomyces cerevisiae (SC) at 1 g/kg. At the same time, FM was replaced with yellow mealworm (Tenebrio molitor) meal (TM) with or without SC at 1 g/kg. The growth performance indices (final weight, weight gain, and SGR), and the feed utilization indices (FCR and PER) were markedly affected by the protein source (FM or TM) and dietary SC (P < 0.05). The protein source (FM or TM) significantly (P < 0.05) affected the whole-body protein and lipid contents, while the moisture and ash contents were unaffected (P > 0.05) by TM or SC. The growth of the intestinal villi showed a marked increase in both height and branching in the treated groups with SC along the whole length of the intestine. Furthermore, the immune cell infiltration was prominent near the intestinal crypts of the middle intestinal segments in the supplemented groups by SC. Dietary TM and SC revealed improved hepatic parenchyma in the liver tissue better than other groups. The hematological indices, including hemoglobulin, hematocrit, red blood cells, and white blood cells, were markedly affected by dietary SC (P < 0.05). The lysozyme activity and phagocytic index were markedly affected by dietary SC, while phagocytic activity was affected by dietary TM (P < 0.05). The catalase, glutathione peroxidase, and malondialdehyde were markedly affected by the interaction between dietary protein source and SC, while superoxide dismutase was affected by dietary SC (P < 0.05). In conclusion, adding SC could enhance the utilization of TM by Nile tilapia with positive effects on the intestinal and liver histological features and the immune and antioxidative responses.

Effect of prolonged feeding of broodstock diet with increased inclusion of essential n-3 fatty acids on maturing and spawning performance in 3-year-old Atlantic salmon (Salmo salar)

Atlantic salmon (Salmo salar) broodstock recruits are normally fed a specialized diet with a higher content of essential nutrients for a limited time period prior to fasting and transfer to freshwater. Typically, this period lasts for about six months, but may vary among producers. Reduced use of marine ingredients in commercial salmon diets during the last decades has affected the content of essential nutrients, such as n-3 long chained polyunsaturated fatty acids (LC-PUFA), minerals and vitamins. Furthermore, to minimize the risk of losses and implement new breeding achievements faster, breeding companies have shortened the production cycle of broodstock from 4 to 3 years, which may affect the number of fish that are large enough to mature. In the present study, we have extended the broodstock feeding period from 6 to 15 months prior to the freshwater transfer giving a higher content of n-3 LC-PUFA (higher inclusion of marine oils) from February to December (Phase 1), and thereafter a diet with a higher energy content to ensure growth towards the spring and maturation (Phase 2). Four sea cages with approximately 80.000 salmon postsmolt, two sea cages with males and two with females, were given a control diet and an experimental diet. Samples were taken in Phase 1 at start (1.7 kg), mid (3.4 kg) and end Phase 1/start of Phase 2 (8.3 kg), and end of Phase 2 (13.4 kg). The fish were thereafter fasted, and selected fish transferred to landbased freshwater tanks where light and temperature were used to manipulate the spawning time of the fish in two groups (early or late). Due to disease in the facility, measures of egg quality and hatching were only obtained from the early group. During the trial and spawning period, biometrical measurements were recorded, and samples of liver, gonad, fillet and red blood cells (RBC) were collected for fatty acid composition and blood plasma for analysis of lipid and health-related parameters. Samples were also collected for gonadal transcriptomic analysis by microarray and qPCR (end Phase 2) and plasma steroids (end Phase 2, mid maturation and spawning). Males fed the test diet had a larger body size compared to the control group at the end of Phase 2, while no differences were observed between dietary groups for the females. Total mortality in the trial was lower in the test group compared to the control, losses were caused mainly by sea lice treatments, loser fish or cardiomyopathy syndrome (CMS). The dietary LC-PUFA levels in the test diet were reflected in the tissues particularly during Phase 1, but only different in the fillet samples and eggs at the end of Phase 2 and at spawning. Plasma sex steroids content increased at mid maturation and showed lower levels of androgens and estrogens in females fed the test diet compared to the control. At the end of Phase 2, transcriptional analysis showed upregulation of steroidogenic enzymes, although not reflected in changes in plasma steroids in Phase 2, indicating changes to come during maturation. The differences in LC-PUFA content in tissues and plasma steroids did not appear to affect fecundity, sperm quality, egg survival or hatching rate, but the test group had larger eggs compared to the control in the early spawner-group. Prolonged feeding of n-3 LC-PUFA to pre-puberty Atlantic salmon broodstock appears to be important for higher survival in challenging sea cage environments and has an effect on sex steroid production that, together with high energy diet during early maturation, cause the test group to produce larger eggs.

Comparison of different papaya forms on the growth performance, immune response, antioxidative capacity, and caecal microbiota of Japanese Quails

Papaya is a sparsely branched tree and grows in many tropical and subtropical areas. Herein, this study compared the effects of papaya at 0.75 % as seeds meal (PSM), leaves meal (PLM), latex powder (PLP), or a mixture of them (PMIX) on the performances of Japanese quails. Two hundred unsexed Japanese quail (1st week-old) with an initial body weight of 21.08 ± 0.32 g were allocated into five experimental groups in cages with free access to water and test diets. Birds fed diets enriched with PSM, PLM, PLP, or PMIX for 55 weeks. The results showed that quail groups fed on papaya diets exhibited improved (P < 0.05) final weight, weight gain (WG), and feed conversion ratio (FCR) than the control. Dietary PLP or PMIX resulted in a remarkable WG enhancement, while PMIX reduced the FCR (P < 0.05). Activities of digestive enzymes (amylase, trypsin, and chymotrypsin) were enhanced (P < 0.05) with dietary papaya, especially in birds fed on PLP. Quails fed on PLM, PLP, or PMIX diets had reduced albumin/globulin ratio (A/G), triglycerides, total cholesterol, and low-density lipoprotein levels. At the same time, the level of high-density lipoprotein and the activity of aspartate aminotransferase increased (P < 0.001) by dietary PLP and PMIX. Moreover, higher total antioxidant capacity, superoxide dismutase, and lower malondialdehyde were recorded with papaya supplements than with the control. A similar trend was recorded for immunoglobulin G and M (IgG and IgM), phagocyte activity, and phagocyte index. Interestingly, low caecal harmful microbiota populations were observed in birds treated with papaya. In conclusion, the dietary inclusion of different papaya parts (leaves, seed, latex, and their mixture) can improve the productive performance, immunity, antioxidant indices, intestinal enzymes, and decline intestinal pathogens of growing Japanese quails.

Effect of fenugreek seed supplementation on fasting and postprandial blood glucose level in type 2 diabetic subjects

Diabetes mellitus has a high prevalence, morbidity and mortality globally. Management of type 2 diabetes is difficult with synthetic drugs as they cause many side effects and have some limitations. Thus, as an alternative and immense interest in medicinal plants with indigenous, inexpensive fenugreek (Trigonella foenum-graecum L.) is considered to be a potent food-based treatment for managing type 2 diabetes. This study was undertaken to evaluate the blood glucose levels and diabetes status with the consumption of fenugreek seed powder in type 2 diabetic patients. In a clinical trial study, 49 type 2 diabetic patients were pooled using randomization and divided into two groups (controlled and exposed group). The exposed group was placed on 10 g/day of powdered fenugreek seeds soaked in water for 60 days, while the control group was not placed on any test diet. Demographic, clinical characteristics, fasting blood glucose (FBG) and postprandial blood glucose (PBG) were measured before and after the study. No adverse reaction was found after the treatment resumed and all participants finished the trial. Findings showed that 20.83% of the patients who took the supplementation had reached the non-diabetic state where zero success rates were observed in the control group. Multivariable linear regression demonstrated that patients’ blood glucose level was significantly associated with fenugreek supplementation (p &lt; 0.001) and the type of therapy (p &lt; 0.05) while adjusted with their demographic variables, physical and medical conditions. When adjusted for covariates, fasting and postprandial blood glucose in the exposed group was estimated to be 2.38 mmol/L (95% CI: -3.45, -1.32, p &lt; 0.001) and 4.18 mmol/L (95% CI: -5.41, -2.95, p &lt; 0.001), which was significantly lower than the control group, respectively. The lowering of blood glucose level in the exposed group was gradually distributed over time while significant changes were observed starting from 30 days of supplementation. It is therefore concluded that fenugreek seed supplementation could be generalized to mitigate the complications of type 2 DM.

Effects of dietary baobab, Adansonia digitata on growth, haemato-immunological status, antioxidant biomarkers, intestinal histomorphometry, gene expression responses, and disease resistance in Nile tilapia, Oreochromis niloticus

This study explored the influences of baobab fruit extract powder (BP) on growth, oxidant-antioxidant balance, immunity, intestinal histology, expression of growth and immune genes, and disease resistance in Nile tilapia. Fish were fed on five test diets supplied with different BP levels as BP0 (control; 0 g kg−1), BP1 (1 g kg−1), BP2 (2 g kg−1), BP3 (3 g kg−1), and BP4 (4 g kg−1) for two months. Results revealed that dietary BP improved the growth in all BP groups compared with the BP0 group, with the best values apparent in the BP4 group. However, dietary BP did not affect the whole-body chemical composition and survival rates in all groups. Serum immunity biomarkers (lysozyme, myeloperoxidase, and bactericidal activities) were enhanced in all BP groups compared to the BP0 group. Hepatic antioxidant status significantly improved, as manifested by increases in the hepatic CAT, SOD, and T-AOC and decreases in MDA concentrations in BP groups compared to the controls. Of interest, dietary BP supplementation significantly increased the expression of growth-related genes (ghr1, ghr2, igf-1, and igf-2) in the liver and immunity-associated genes (inf-γ1, lyz, il-1β, il-10, and hepcidin) in the spleen of BP-treated fish in comparison with the controls. The intestinal histological sections revealed no significant variations among all groups with normal histoarchitecture and goblet cells. After experimental infection with Aeromonas hydrophila, the survival rates (%) in the BP0, BP1, BP2, BP3, and BP4 groups were 23.33, 43.33, 56.67, 63.33, and 70.00, respectively, suggesting the positive roles of BP in increasing the fish disease resistance. To conclude, dietary BP could improve growth (particularly in the BP4), serum immunity, antioxidant capacity, and transcription of growth and immune genes in O. niloticus. In addition, the highest disease resistance was also found in the BP4 group. All in all, BP at a dose rate (4 g kg−1 diet) could be regarded as a functional feed supplement for tilapia farming.

Effects of l-ascorbic acid on growth, non-specific immunity, antioxidant capacity, and intestinal and hepatopancreatic histology of red swamp crayfish, Procambarus clarkii

This study investigated the dietary effects of coated l-ascorbic acid (LA) on growth, feed utilization, survival, serum biochemical indices, immunity, antioxidant capacity, and intestinal and hepatopancreatic histology of the pre-adult red swamp crayfish. Four isoproteinous and isolipidic diets were formulated to contain several LA levels as 0, 1300, 1600, and 1900 mg/kg and designated as control (LA0), LA13, LA16, and LA19, respectively. However, the analyzed LA concentrations in diets were 0.00, 199.57, 360.45, and 487.50 mg/kg in LA0, LA13, LA16, and LA19, respectively. Triplicate treatments of crayfish (21.60 ± 0.14 g) were fed the test diets and reared in fiberglass tanks with a density of 20 individuals per each for eight weeks. Results revealed that all LA treatments had significantly enhanced growth performance compared to the control. Of interest, the LA16 treatment recorded the highest final tank biomass, biomass gain, total feed intake, condition factor, and muscle yield among the other treatments. The tank feed conversion ratio was significantly decreased in LA treatments compared to the control. Moreover, dietary LA16 and LA19 had significantly higher survival rates (93.3%) compared to (85.0%) in the LA0 group. All dietary doses of LA significantly increased serum parameters (total protein, albumin, globulin, lysozyme activity) and respiratory burst activity compared to the LA0 treatment. Dietary LA16 significantly boosted the hepatopancreatic antioxidant capacity, manifested by decreased malondialdehyde concentrations, increased catalase, superoxide dismutase, and glutathione peroxidase enzyme activities, and reduced glutathione content compared to the LA-free diet. A normal histoarchitecture of the hepatopancreatic tubules was found in all LA treatments except with some minor degenerative changes in the tubular lumen, and hepatopancreatic cells associated with enlarged nuclei were found in the LA19. However, normal intestinal histoarchitecture was found in all treatments with no recorded intestinal lesions. Of interest, the polynomial regression performed on the analyzed LA concentrations suggested that 380 mg/kg would be suitable to provide maximal biomass gain for pre-adult crayfish. In conclusion, results revealed that coated LA could enhance the growth, immunity, and antioxidant capacity of pre-adult red swamp crayfish, suggesting its potential as a functional and necessary micronutrient for crayfish diets.

Dietary Supplementation with Nucleotides, Short-Chain Fructooligosaccharides, Xylooligosaccharides, Beta-Carotene and Vitamin E Influences Immune Function in Kittens

Nucleotides, short-chain fructooligosaccharides (scFOS), xylooligosaccharides (XOS), β-carotene and vitamin E are reported to enhance immune function; however, the evidence of this in cats is limited. The aim of this study was to determine the immunomodulatory effects of these ingredients in kittens. Forty domestic short hair kittens were designated in litters to control or test diet for 28 weeks. Test diet was fortified with 0.33 g nucleotides, 0.45 g scFOS, 0.3 g XOS, 0.7 mg β-carotene and 66.5 mg vitamin E per 100 g diet. Kittens were vaccinated against feline parvovirus (FPV) and herpesvirus (FHV) at 10, 14 and 18 weeks. Kittens remained healthy, with no measured evidence of adverse health. Serum FPV and FHV antibody titres were significantly (p &lt; 0.05) higher in the test diet group at week 23 and 27, respectively. A significantly (p &lt; 0.05) higher proportion of test diet group kittens demonstrated an adequate response (four-fold titre increase) to FHV vaccination and a significantly (p &lt; 0.05) higher proportion reached a protective antibody titre for FHV. Serum IgM was significantly (p &lt; 0.05) higher in the test diet group. The test diet group demonstrated a stronger humoral immune response to vaccination, suggesting the diet supports immune defence, enabling a greater response to immune challenges.

Anthropometric and Biochemical Indices of Infants fed Complementary Foods developed from Millets, Orange-Fleshed Sweet Potatoes, Carrot, Periwinkle and Oyster Meat Flour Blends

Purpose: This study examined the anthropometric and biochemical indices of infants fed complementary foods developed from millets (M), orange-fleshed sweet potatoes (OFSP), carrot (CF), periwinkle meat (PMF) and oyster meat flour (OMF) blends.&#x0D; Materials and Methods: Six different blends of flour were formulated using the recommended guideline for the formulation of complementary food for infants 6 – 12 months. The blends were as follows 89: 11 M/C; 70:30 M/OFSP; 57:32:11 M/OFSP/C; 65:20:5:10 M/OFSP/C/OMF; 49:29:7:15 M/OFSP/C/PMF and 70:13:3: 7:7 M/OFSP/C/PMF/OMF while Cerelac was used as the control diet. Thirty-five children aged 6-12 months enrolled in this study. Seven groups comprising of 5 children each consumed cerelac (control diet), millet/carrot (Test diet I) millet/OFSP (test diet II), millet/OFSP/carrot (test diet III), millet/OFSP/carrot/oyster (test diet IV), millet/OFSP/carrot/periwinkle (test diet V), and millet/OFSP/carrot/periwinkle/oyster (test diet VI), respectively.&#x0D; Findings: The children were fed with 50 g/day of the diets over a 6 months period during which anthropometric (weight, length, mid-upper arm circumference, head circumference, and chest circumference) and biochemical assessments (iodine level, hemoglobin level, calcium level, and vitamin A level) were carried out before and after test product ingestion. All children fed on the test diets had an increase in anthropometric parameters. Test diet VI had the highest percentage effect on biochemical and anthropometric parameters at the end of the study. The effect of test diet VI on the hemoglobin levels of the infants was significantly (p&lt;0.01) higher than other test diets.&#x0D; Implication to Theory, Practice and Policy: Dietary interventions incorporating carrots, OFSP, periwinkle, and oyster exhibited favorable impacts on the nutritional well-being of infants. Consequently, it ought to be regarded as a superior choice when devising nutrition initiatives aimed at enhancing the nutritional condition of children residing in regions where millet-based porridge prevails as the primary complementary food.

Chronic larval and adult honey bee laboratory testing: Which dietary additive should be considered when a test substance is not solubilized in acetone?

Chronic toxicity tests on adult and larval honey bees (Apis mellifera) can require the use of dietary additives (solvents, emulsifiers, adjuvants and viscosifier agents) when the active ingredient of plant protection products cannot be dissolved or does not remain stable and homogeneous within the test diets. Acetone is the widely used and accepted solvent allowed within the international regulatory guidelines, but it can be ineffective in keeping certain compounds in solution and can cause toxicity to adults and larvae. In this publication, we present an evaluation of alternative additives in adult and larval diets. Six dietary additives including five solvents (ethanol, isopropanol, n-propanol, propylene glycol and triethylene glycol) and a viscosifier agent (xanthan gum) at five concentrations along with a negative control and a solvent control (acetone) were investigated at seven laboratories. The safe levels for bees were determined for each of the additives used in the 10-day chronic adult and 22-day chronic larval tests. In the 10-day chronic adult study, ethanol and isopropanol were found to be safe at concentrations ≤ 5.0 %, while xanthan gum can be reliably used at concentrations ≤ 0.1 %. Greater variability across laboratories was observed for N-propanol, propylene glycol, and triethylene glycol and these agents may cause mortality when added to diets at concentrations above 0.25–0.5 %. The safe levels of additives to larval diet in the 22-day chronic larval test had a greater variability and were generally lower than what were observed for adult diet. Our results do not recommend the inclusion of ethanol or n-propanol into the larval diet, and isopropanol, propylene glycol, and triethylene glycol may cause mortality at concentrations above 0.25–0.5 %. Safe levels for xanthan gum were more variable than what was observed for adults, but it can be used reliably at concentrations ≤ 0.05 %. Our analyses conclude that several additives can be integrated successfully in honey bee laboratory bioassays at levels that cause low mortality to adults and larvae.

Metal-amino acid complexes (Zn, Se, Cu, Fe, and Mn) enhance immune response, antioxidant capacity, liver function enzymes, and expression of cytokine genes in Nile Tilapia reared under field conditions.

In the present study, we investigated the effects of partial or total replacement of dietary inorganic trace materials (ITM) with metal-amino acid complexes (MAACs) on immune response, antioxidant capacity, cytokine genes expression, and overall health status of Nile Tilapia Oreochromis niloticus reared in in-pond hapas (mesh cages) under field conditions. All-male Nile Tilapia with an average initial weight of about 90 g fish-1 were stocked into the hapas, in quadruplicates, at a density of 60 fish per hapa (30 fish m-3 ). The fish in each hapa were acclimatized to culture conditions and test diets for 1 week. Water quality parameters, including temperature (°C), pH, dissolved oxygen (mg L-1 ), and total ammonia (mg L-1 ), were monitored regularly. The MAACs were formulated to contain the same mineral concentrations found in the inorganic premix. Metal-amino acid complexes replaced the ITM premix at 0 (control), 25, 50, 75, and 100% levels (Table 1). The diets were fed to caged Nile Tilapia twice a day, for 80 days, at a daily rate of 3% of their body weights. The fish were weighed every 10 days, and the daily rations were readjusted. At harvest, fish in each hapa were collected, counted, and weighed collectively. Five fish from each hapa were rapidly anesthetized, and used for chemical and physiological analyses, including antioxidant and immune response analyses, liver function analysis, and gene expression. The activities of lysozyme, respiratory burst (%), alternative complement (ACH50), phagocytic cells, phenoloxidase, superoxide dismutase, glutathione peroxidase, and liver function enzymes were all improved with increasing supplemental MAACs up to the 50% substitution level. The expression of cytokine genes, including interferon, tumor necrosis factor, interleukin-1, serum alkaline phosphatase, the integrated microbial genomes, chloramphenicol acetyltransferase, and transforming growth factor genes, was significantly upregulated in fish fed on MAAC-supplemented diets compared with the control group. The 50% MAAC level produced the highest upregulation of these genes, whereas gene expression decreased with increasing dietary MAAC levels to 75% and 100%. The quadratic regression analysis indicated that about 60-65% MAAC is required for maximum promotion of immunological and oxidative stress responses, gene expression, and overall health status of Nile Tilapia reared in in-pond hapas under field conditions. Replacement of the ITM premix with a MAAC premix enhanced the immune and antioxidant responses of Nile Tilapia.

Effect of different types of bacterial single cell protein on feed intake, digestibility, growth and body composition of Pacific white shrimp (Penaeus vannamei)

This study assessed the potential of four bacterial (Methylococcus capsulatus) single cell protein (SCP) products as alternative protein sources for Pacific white shrimp (Penaeus vannamei) diets. A growth trial and a digestibility trial were undertaken, during which the bacterial SCP products were compared with a high-quality fishmeal and a soy protein concentrate, regarding their impact on ingredient digestibility, growth, feed intake and whole-body composition of juvenile P. vannamei. Seven diets were formulated; one reference diet (REF) and six test diets. The test diets consisted of 85% of the REF diet and 15% of a test ingredient. Ingredients tested were four bacterial SCP products (SCP1–4), which differed in processing conditions, fishmeal (FM) and soy protein concentrate (SoyProt). Growth and feed utilization were similar for P. vannamei fed either the FM diet or one of the bacterial SCP diets, whilst lowest growth and feed utilization were observed for shrimp fed the SoyProt diet. Final whole-body protein content did not differ between shrimp fed the FM diet or one of the four bacterial SCP diets. However, shrimp fed the SCP diets had a significantly higher final phosphorus body content and a higher phosphorus retention than shrimp fed the FM or SoyProt diets. This indicates a higher phosphorus availability in the bacterial SCP products compared to FM and SoyProt. Protein digestibility of the SCP products was similar to FM, whilst amino acid (AA) digestibility was comparable to FM for three of the four SCP products (SCP1, SCP2 and SCP4). The SCP3 product showed the lowest digestibility for most AA, indicating a possible influence of processing conditions on AA availability of bacterial SCPs. Overall, this study highlights that bacterial SCP originating from M. capsulatus is a viable alternative protein source for Pacific white shrimp diets, but processing conditions should be taken into account.

Effects of a high-protein, increased-fibre, dry diet supplemented with omega-3 fatty acids on quality of life in dogs undergoing chemotherapy.

Quality of life (QOL) in dogs with cancer is a key consideration in the assessment of cancer treatment options. Despite interest in dietary strategies to improve management of oncology patients, there have been very few clinical studies showing the impact of diet on adverse effects of chemotherapy in dogs. This study was a randomised, controlled, double-blinded, multicenter clinical trial to investigate a high-protein, increased-fibre diet supplemented with omega-3 fatty acids, for dogs with cancer undergoing standard-of-care chemotherapy. Client-owned dogs with newly diagnosed grade 2 or higher mast cell tumours (or non-resectable/incompletely resected tumours) or multicentric lymphoma were randomised to receive the test diet (n = 24) or control diet (n = 21) for 8 weeks. Primary outcomes were QOL assessments, faecal scores, and blood concentrations of C-reactive protein and monocyte chemoattractant protein-1. Of 12 QOL parameters, 10 significantly improved from baseline to Week 8 in the test group compared with one in the control group. However, differences between the two groups were only statistically significant for 'frequency of signs of illness' (P = .009). There were no significant differences in the incidence of any adverse events, including gastrointestinal adverse events or clinically significant differences in laboratory parameters or faecal scores between the two groups. The absence of an observed negative impact of the test diet, combined with the magnitude of QOL improvements associated with the diet, suggest that a larger trial is warranted.