Effects of dietary hydrolysate supplementation on growth, body composition, hematological responses, and liver histology of juvenile giant trevally (Caranx ignobilis Forsskal, 1775).

A feeding study was conducted to investigate how fish protein hydrolysate (FPH) supplementation affected the growth, feed utilization, body composition, and hematology of juvenile giant trevally (Caranx ignobilis Forsskal, 1775). Seven isonitrogenous (52% protein) and isocaloric diets (10% lipid) were formulated, wherein shrimp hydrolysate (SH) and tuna hydrolysate (TH) were used to replace fishmeal at inclusion levels of 0 (control), 30, 60, and 90 g/kg and labeled as control, SH30, SH60, SH90, TH30, TH60, and TH90, respectively. Each diet was fed to triplicate groups of juvenile giant trevally for 8 weeks. The results showed higher final body weight and specific growth rate in fish fed SH30, SH60, TH30, and TH60 than fed control diet. No difference was observed in feed intake, but reduced feed conversion ratio (FCR) was found in fish fed SH30, SH60, TH30, and TH60, demonstrating these diets improved feed utilization. TH90 caused deposition of lipid droplet in the hepatocyte, a sign of liver damage. Total monounsaturated fatty acids, polyunsaturated fatty acids (PUFA), and highly unsaturated fatty acids in fish were not affected by FPH supplementation. Fish fed TH30 showed lower ∑n - 3 PUFA than the fish fed remaining dietary treatments. The elevated serum protein was seen in fish fed control, SH30, SH60, and TH30, demonstrating that these diets were beneficial for the innate immune response in giant trevally. The results indicate that TH and SH could be incorporated into diets of giant trevally at 30-60 g/kg, replacing 7%-13% fishmeal with enhanced growth and health benefits.

Potential effects of probiotics (immunobacteryne; IMB) on growth performance, feed efficacy, blood biochemical, redox balance, nonspecific immunity and heat-shock protein expression of Nile tilapia (Oreochromis niloticus) fingerlings.

The supplementation of aquafeed with probiotics is recommended for feasible aquaculture activities. Therefore, the aim of current study was to investigate the potential effects of probiotics on growth performance, feed utilization, biochemical attributes, redox status and immunity response as well as the transcription of heat-shock protein 70 (HSP70) and insulin-like growth factor-1 (IGF-1) genes of Nile tilapia (Oreochromis niloticus; n = 120). Fish with an initial weight of 8.17 ± 0.02 g/fish were randomly divided into four treatment groups and were fed diets containing 0, 0.5, 1 and 1.5 mg immunobacteryne (IMB)/kg diet respectively. Dietary IMB at 1.5 g/kg diet significantly improved the growth performance, feed consumption and growth hormone secretion of the experimental fish (p < 0.05). The 1 or 1.5 g IMB/kg diet boosted phagocytic activities and innate immune response. Serum total protein, total cholesterol, triglycerides and glucose were significantly increased in the groups that were fed 1 and 1.5 mg IMB/kg diet compared to the control (p < 0.05). Meanwhile, the levels of uric acid, creatinine, liver enzymes (aspartate transaminase and alanine transaminase) and cortisol hormone were significantly reduced in the aforementioned treated groups compared to the control (p < 0.05). All fish fed IMB-supplemented diet showed a significant increase in the expression of IGF-1 gene, while the transcription of HSP70 was significantly decreased (p < 0.05). In conclusion, the dietary inclusion of IMB (1 g/kg diet) enhanced growth promoters, feed efficacy, blood biochemical, redox balance and nonspecific immune responses in Nile tilapia fingerlings.

Dietary supplementation of VA enhances growth, feed utilization, glucose and lipid metabolism, appetite, and antioxidant capacity of Chinese perch (Siniperca chuatsi).

The aim of this study was to investigate the effect of dietary vitamin A on juvenile Chinese perch (Siniperca chuatsi). Chinese perch were fed with five experimental diets containing 0, 20, 40, 60, and 80 mg VA·kg-1 for 8 weeks. Results showed that dietary vitamin A significantly influenced the fish's growth, feed utilization, glucose and lipid metabolism, appetite, and antioxidant capacity. Vitamin A-supplemented groups had higher weight gain rate (WGR) and specific growth rate (SGR) compared to the control group. Feed conversion ratio (FCR) was also lower in the vitamin A-supplemented groups. Dietary vitamin A had no significant effect on the survival rate (SR). Compared to the control group, fish fed with vitamin A had increased feed intake (FI), and the expression of appetite-promoting genes (npy and agrp) was significantly higher in the 40 mg VA·kg-1 group. Vitamin A also enhanced the utilization of dietary protein by Chinese perch. The serum glucose content of the fish fed with 40 mg VA·kg-1 diet was significantly higher than that of the control group and 20 mg VA·kg-1 diet, indicating that the promoting effect of VA on gluconeogenesis was greater than that on glycolysis. Additionally, dietary vitamin A increased the expression of lipid metabolism-related genes (hl and fas) and antioxidant genes (nrf2 and gpx) in the fish. These results suggest that the optimal vitamin A requirement of juvenile Chinese perch bream was estimated to be 37.32 mg VA·kg-1 based on broken-line regression analysis of WGR. In conclusion, this study provides valuable insights into the potential benefits of dietary vitamin A on the growth, metabolism, and antioxidant capacity of Chinese perch.

Protein-sparing effects of lipids in the diet of golden pompano (Trachinotus ovatus): evaluation of growth, feed utilization, and lipid metabolism.

To investigate the influences of dietary protein and lipid levels on the growth, feed utilization, morphometric parameters, body composition, serum biochemical parameters, and lipid metabolism of golden pompano (Trachinotus ovatus), nine test diets containing three protein levels (35%, 40%, and 45%) and three lipid levels (8%, 13%, and 18%) were designed in the present study. Each diet (named D1-D9) was randomly assigned to feed triplicate groups of golden pompano juvenile (initial weight ~ 70 g) for 50 days. The results showed that the dietary lipid levels positively correlated with weight gain, specific growth rate, and protein efficiency ratio (PER), suggesting that the high lipid diets (18%) can be efficiently utilized in this fish species. The dietary protein levels have no significant influences on the growth and feed utilization except for the PER. Increasing dietary protein levels resulted in a decrease in hepatosomatic index (HSI), viscerosomatic index (VSI), and intestinal somatic index (ISI), while the dietary lipid level did not have a significant impact on morphological indices except for ISI. The dietary protein and lipid levels had no significant influences on the contents of crude lipid, crude ash, and moisture of whole body, while the crude protein contents was significantly affected by the dietary protein levels. Serum biochemical indexes, including cholesterol (CHO), triglycerides (TG), high-density lipoprotein cholesterol (HDL), and low-density lipoprotein cholesterol (LDL), as well as HDL/LDL ratio were significantly affected by the dietary lipid levels, but not by the dietary protein levels. The expression levels of genes and their associated proteins involved in hepatic lipogenesis (Srebp-1c and Fas) and fatty acids ß-oxidation (Pparα and Cpt-1) were up-regulated with increasing dietary lipid levels, while the former was up-regulated, and the latter was down-regulated with increasing dietary protein levels. Considering the present results in terms of growth performance, feed utilization, morphometric parameters, and lipid metabolism, the recommended dietary protein and lipid levels for golden pompano are 40% and 18%, respectively. The findings suggested that this species exhibits a significant protein-sparing effect on lipid utilization.

Can dietary fermented total mixed ration additives biological and chemical improve digestibility, performance, and rumen fermentation in ruminants?

The quantity and quality of animal feed are important factors for efficient and profitable animal farming. Feed ingredients and supplementation with high-density energy and nitrogen would be potentially useful on the farm. The new approach to feeding has shifted from animal-based diets to more readily fermentable feedstuffs in ruminants to meet the increased production of high-yielding animals. These methods encourage the use of fermented total mixed ration (FTMR). An advantage of feeding FTMR as opposed to total mixed ration (TMR) is the opportunity for a development alternative to efficiently handle ruminant diets. FTMR is a method to promote progressive nutrient utilization, extend the preservation of feed by preventing spoilage, and reduce anti-nutritive substances in feeds. Ruminal protein and starch degradability were increased due to proteolysis during storage by ruminants fed ensiled rations. The results found that FTMR can reduce the pH level and increase the lactic acid content of ensiled materials, which results in better quality feed and longer storage times. In addition, it can increase dry matter intake, growth rate, and milk production when compared with TMR. It was shown that the use of FTMR diet was effective for animal production. However, FTMR was rapidly spoiled when exposed to air or feed-out, particularly in hot and humid climates, resulting in a decrease in lactic acid concentration, an increase in pH, and the loss of nutrients. Thus, the appropriate method for enhancing the quality of FTMR should be considered.

Probiotic effect of Bacillus spp. isolated from African nightcrawler (Eudrilus eugeniae) on the performance of Nile Tilapia (Oreochromis niloticus L.).

This study evaluated the effects of the probiotic Bacillus spp. isolated from African nightcrawler (Eudrilus eugeniae) on the growth and survival performances of Nile tilapia (Oreochromis niloticus). A total of 400 Nile tilapia fingerlings (1.76 ± 0.07 g) were equally and randomly distributed into 20 glass aquaria and divided into five experimental groups with four replicates. Each experimental group was fed with a commercial diet (control) supplemented (at 108 CFU·g-1) with one of the four Bacillus spp. (ANSCI9, BFAR9, RM3, and RM10) at five percent of their body weight. After 30 days of feeding, the surviving fish were challenged with Aeromonas hydrophila to observe their survival. The treatment groups supplemented with BFAR9 (2.73 ± 0.26 g) and RM10 (3.15 ± 0.30 g) showed significantly higher (P < 0.05) absolute growth than the control (2.20 ± 0.16 g) group. Furthermore, those given with RM10 had better (P < 0.05) specific growth rate (SGR) (1.60 ± 0.10%·day-1) relative growth rate (RGR) (181.39 ± 18.16%) and feed conversion ratio (FCR) (1.99 ± 0.13) compared to the control group (SGR = 1.29 ± 0.07%·day-1; RGR = 129.84 ± 9.77%; FCR = 2.60 ± 0.16). The challenge test revealed that all Bacillus spp.-treated groups showed significantly higher (P < 0.05) survival rates (ANSCI9 = 82.5 ± 8.16%; BFAR9 = 80.0 ± 10.00%; RM3 = 77.5 ± 20.82%; RM10 = 85.0 ± 10.00%) than the control group (55.00 ± 19.15%), with the highest relative level of protection recorded for RM10 (66.67%). These results revealed that the probiotic Bacillus spp. isolated from E. eugeniae improved the growth, feed utilization, waste excretion, and the disease resistance of Nile tilapia.

A study of the potential effect of yellow mealworm (Tenebrio molitor) substitution for fish meal on growth, immune and antioxidant capacity in juvenile largemouth bass (Micropterus salmoides).

This study aimed to evaluate the effects of partial replacement of fish meal (FM) with yellow mealworm (Tenebrio molitor, TM) on the growth performance, food utilization and intestinal immune response of juvenile largemouth bass (Micropterus salmoides). Seven diets containing increasing levels of TM (FM substitution) were designed (approximately 0% (0%), 4% (11.1%), 8.1% (22.2%), 12.2% (33.3%), 16.3% (44.4%), 20.4% (55.5%), and 24.5% (66.6%), designated TM0, TM11, TM22, TM33, TM44, TM55, and TM66, respectively). 420 fish were randomly selected and placed in 21 cages (1 m*1 m*1 m, 7 treatments for triplicate, 20 fish per cage). Fish (initial weight 6.25 ± 0.03 g) were fed seven isonitrogenous (47%) and isocaloric (19 MJ kg-1) diets to satiety twice daily for 8 weeks. Compared to the control group (TM0), TM11 showed no significant difference in the weight gain rate (WGR), specific growth rate (SGR) or feed conversion ratio (FCR), while all other TM inclusion groups presented different degrees of decline. There was no significant difference in the whole-body composition among all groups (P > 0.05). Plasma total protein (TP), triglyceride (TG) and albumin (ALB) contents were significantly decreased in TM55 and TM66 (P < 0.05). The highest plasma aspartate transaminase (AST) activity was observed in TM66 (P < 0.05). TM33, TM44 and TM55 showed the lowest activities of plasma alanine amiotransferase (ALT) and alkaline phosphatase (ALP) (P < 0.05). Moreover, increased mRNA levels of superoxide dismutase (SOD) and catalase (CAT) were measured in the TM11 to TM55 groups, while intestinal SOD activity peaked in TM11 (P < 0.05). With the exception of TM11, the other TM inclusion groups showed significant inhibition of the relative expression of RelA, C3 and TNF-α (P < 0.05). All experimental groups exhibited lower expression of IL-10 than TM0 (P < 0.05). The TM11 group showed significantly upregulated expression of IL-1ß and TGF-ß (P < 0.05). In addition, TLR2 expression was increased in TM11 and TM22 (P < 0.05). Considering enzyme activities and immune-related gene expression, TM supplementation levels should not exceed 4% (TM11).

Effect of Aspergillus oryzae on ruminal fermentation, feed intake and dry matter digestibility in cows fed forage-based diets.

The present study was conducted to investigate the effect of Aspergillus oryzae inclusion on ruminal fermentation, feed intake and dry matter (DM) apparent digestibility in cows fed Cenchrus purpureus forage and concentrate. Cows were randomly assigned in a replicated 4 × 4 Latin square design, into four treatments: control and three doses of A. oryzae culture (1, 2 and 3 g/d). Experimental periods had 21 days, in which 14 days were allowed for treatment adaptation and 7 days for sampling. Addition of 2 g/d increased (p = 0.0054) total anaerobic bacteria. For cellulolytic bacteria and fungal populations increases (p < 0.0001) with all doses were observed. Highest concentrations of total short chain fatty acids (SCFAs), acetate, isovalerate and valerate were observed with 2 g/d of additive. Propionate concentration and acetate: propionate (Ac:Pr) ratio were unaffected by treatments. A. oryzae addition did not modify ruminal pH. A decrease of ammonia-N was observed with 2 g/d of additive. Dry matter intake and apparent digestibility of DM were increased (p = 0.0171 and p = 0.0023, respectively) with the fungal culture addition. It is concluded that Aspergillus oryzae strain H/6.28.1 stimulates ruminal fermentation and improves feed intake and dry matter apparent digestibility in cows feeding with Cenchrus purpureus forage and concentrate.

Dietary Azomite, a natural trace mineral complex, improved the growth, immunity response, intestine health and resistance against bacterial infection in largemouth bass (Micropterus salmoides).

Azomite is a hydrated calcium sodium aluminosilicat rich in rare earth elements. To investigate the dietary effects of Azomite on growth, intestine microbiota and morphology, immunohematological changes and disease resistance, seven diets with Azomite supplementation of 0 (the control), 1.0, 2.0, 3.0, 4.0, 5.0 and 6.0 g/kg (A0, A1, A2, A3, A4, A5, A6), were prepared and fed to largemouth bass, Micropterus salmoides (7.96 ± 0.19) for 60 days. The results revealed that the weight gain (WG) increased first and then decreased with the increasing dietary Azomite, and the A2 group presented the highest WG and lowest feed conversion ratio among all the groups. The supplementation of 2.0 g/kg Azomite significantly increased the intestine protease activity, the crude protein of whole body and protein retention (P < 0.05), and high inclusion of Azomite (6.0 g/kg) significantly reduced the lipid retention (P < 0.05). The amounts of red blood cells in A5, A6 groups, white blood cells in A3, A5, A6 groups and lymphocyte in A2-A6 groups were all significantly higher than those in the control group (P < 0.05). In addition, serum superoxide dismutase and catalase activities in A5, A6 groups, and serum alkaline phosphatase and lysozyme activities in A2-A4 groups showed significantly higher values than the control group (P < 0.05). Intestinal microbiota analysis indicated that the Tenericutes abundance was increased, whereas Proteobacteria abundance was decreased in all Azomite supplemented groups. The villus height in A2-A4 groups, and the villus width in A2 group were significantly higher than those of the control group (P < 0.05). The cumulative mortality was reduced by the addition of 2.0-5.0 g/kg Azomite after challenging with A. hydrophila (P < 0.05). In conclusion, proper addition of Azomite in diets improved the growth, intestine morphology, immune response and disease resistance in largemouth bass, and the optimal inclusion was estimated to be 2.0-3.0 g/kg diet.

Mapping genes for phosphorus utilization and correlated traits using a 4k SNP linkage map in Japanese quail (Coturnix japonica).

A large F2 cross with 920 Japanese quail was used to map QTL for phosphorus utilization, calcium utilization, feed per gain and body weight gain. In addition, four bone ash traits were included, because it is known that they are genetically correlated with the focal trait of phosphorus utilization. Trait recording was done at the juvenile stage of the birds. The individuals were genotyped genome-wide for about 4k SNPs and a linkage map constructed, which agreed well with the reference genome. QTL linkage mapping was performed using multimarker regression analysis in a line cross model. Single marker association mapping was done within the mapped QTL regions. The results revealed several genome-wide significant QTL. For the focal trait phosphorus utilization, a QTL on chromosome CJA3 could be detected by linkage mapping, which was substantiated by the results of the SNP association mapping. Four candidate genes were identified for this QTL, which should be investigated in future functional studies. Some overlap of QTL regions for different traits was detected, which is in agreement with the corresponding genetic correlations. It seems that all traits investigated are polygenic in nature with some significant QTL and probably many other small-effect QTL that were not detectable in this study.

A novel ammoniation treatment of barley as a strategy to optimize rumen pH, feed degradability and microbial protein synthesis in sheep.

BACKGROUND: Meeting the energy and nitrogen (N) requirements of high-performing ruminants at the same time as avoiding digestive disturbances (i.e. rumen acidosis) is a key priority in ruminant nutrition. The present study evaluated the effect of a cereal ammoniation treatment, in which barley grains are combined with urea and enzymes that catalyze the conversion of urea to ammonia to optimize rumen function. Twelve rumen cannulated sheep were randomly divided into two groups and fed a diet containing 60% of ammoniated barley (AMM) or untreated barley supplemented with urea (CTL) to investigate the impact on rumen fermentation and feed utilization. RESULTS: AMM had higher total N content and effective rumen degradable N than untreated barely. AMM sheep had a consistently higher rumen pH throughout the day (6.31 versus 6.03) and tended to have a lower post-prandial ammonia peak and higher acetate molar proportion (+5.1%) than CTL sheep. The rumen environment in AMM sheep favored the colonization and utilization of agro-industrial by-products (i.e. orange pulp) by the rumen microbes leading to a higher feed degradability. AMM sheep also had higher total tract apparent N digestibility (+21.7%) and urinary excretion of purine derivatives (+34%), suggesting a higher N uptake and microbial protein synthesis than CTL sheep. CONCLUSION: The inclusion of AMM in the diet of ruminants represents a valid strategy for maintaining rumen pH within a physiological range and improving N utilization by the rumen microbes, which could have positive effects on the health and productivity of animals in intensive production systems. These findings warrant further studies under conventional farm conditions. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

The influence of coconut oil on the growth, immune, and antioxidative responses and the intestinal digestive enzymes and histomorphometry features of Nile tilapia (Oreochromis niloticus).

The trials of finding non-conventional and alternative aquafeed ingredients are increasing. In this sense, this study evaluated the influence of coconut oil on the growth, feed utilization, immune, and antioxidative responses of Nile tilapia. Five test diets were formulated by mixing coconut oil with the other ingredients at 0, 1, 2, 3, and 4% of the total ration and presented for tilapia for 60 successive days. The final weight, SGR, weight gain (WG), and feed intake were superior in fish delivered 2% of coconut oil (P < 0.05). Concurrently, fish that received 2% coconut oil had lower FCR and higher PER than fish of the control and 4% groups (P < 0.05). Higher lipase activity was observed in fish of 2% and 3% levels than the remaining groups (P < 0.05). Besides, the amylase and protease activities of fish in 1%, 2%, and 3% groups were higher than the 0% level (P < 0.05). The total blood cholesterol, RBCs, and PCV showed higher values in Nile tilapia fed 2% and 3% coconut oil (P < 0.05). The lysozyme and phagocytic activities were higher in fish fed 2% and 3% levels than the control (P < 0.05), while the phagocytic index in 2% and 3% levels was higher than 0% and 4% levels. Furthermore, SOD and CAT were higher in fish fed 1%, 2%, and 3% than fish fed 0% and 4% levels while GSH was higher in fish of 1%, 2%, and 3% than fish fed 0% level (P < 0.05). However, the MDA level was markedly lower in fish fed 25, 3%, and 4% coconut oil than the 0% level (P < 0.05). The intestine's histological structure in all groups appeared normal, forming of intestinal villi projecting from the intestinal wall. Also, the structure of the hepatopancreas had a normal architecture in all groups. To sum up, the inclusion of coconut oil at 2 to 3% is recommended as a replacer for fish oil in Nile tilapia diets.

Effects of graded levels of mineral mixtures (Aquamin® and Agrimin®) supplemented diets on growth, survival, proximate composition, and carcass mineralization of juvenile freshwater prawn, Macrobrachium malcolmsonii (H Milne-Edwards 1844).

The present study investigated the effects of Aquamin® mineral mixture (AQMM) and Agrimin® mineral mixture (AGMM) supplemented diets on growth and chemical composition of juvenile freshwater prawn Macrobrachium malcolmsonii (H. Milne-Edwards, 1844). Experimental diets containing 6 different AQMM levels (Trial 1: 0, 0.5, 1.0, 1.5, 2.0, and 2.5%) and 6 different AGMM levels (Trial 2: 0, 0.5, 1.0, 1.5, 2.0, and 2.5%) were formulated to feed juvenile prawn [initial body weight of 0.82 ± 0.05 g (Trial 1) and 1.24 ± 0.03 g (Trial 2)] for 60 days. Prawn fed diets containing 1.0% of AQMM and AGMM showed significantly increased (P < 0.05) survival rate, weight gain, specific growth rate, protein efficiency ratio, edible flesh weight, and proximate composition (moisture, crude protein, crude fat, and ash), while feed intake and feed conversion ratio were significantly decreased (P < 0.05). Whereas, 1.5-2.5% of AQMM- and AGMM-supplemented diets fed prawn showed a reverse trend when comparing other groups. Moreover, the minerals (macro elements: Ca, P, Mg, Na, and K; trace elements: Cu, Zn, and Fe) were significantly increased (P < 0.05) in the carcass of prawn when fed with 2.5% AQMM- and AGMM-supplemented diets. The present results suggest that the optimal dietary supplementation of AQMM and AGMM at a concentration of up to 1.06 and 1.02%, respectively (based on polynomial regression analysis), improved growth and enhanced the crude protein level of juvenile prawn.

Effects of increasing dietary level of organic acids and nature-identical compounds on growth, intestinal cytokine gene expression and gut microbiota of rainbow trout (Oncorhynchus mykiss) reared at normal and high temperature.

Organic acids (OA) and nature-identical compounds (NIC) such as monoterpenes and aldehydes are well-known growth and health promoters in terrestrial livestock while their application for fish production is recent and their mechanisms of action require further study. Hence, this study tested the increasing dietary level (D0, D250, D500, D1000; 0, 250, 500 and 1000 mg kg feed-1 respectively) of a microencapsulated blend containing citric and sorbic acid, thymol and vanillin over 82 days on rainbow trout to assess the effects on growth, feed utilization, intestine cytokine gene expression and gut microbiota (GM). Furthermore, the effects on intestinal cytokine gene expression and GM were also explored after one week at high water temperature (23 °C). OA and NIC improved specific growth rate (SGR) and feed conversion rate (FCR) during the second half (day 40-82) of the feeding trial, while at the end of the trial protein (PER) and lipid efficiency (LER) increased with increasing dietary level. GM diversity and composition and cytokine gene expression analysis showed no significant differences in fish fed with increasing doses of OA and NIC (82 days) demonstrating the absence of inflammatory activity in the intestinal mucosa. Although there were no statistical differences, GM structure showed a tendency in clustering D0 group separately from the other dietary groups and a trend towards reduction of Streptococcus spp. was observed in the D250 and D1000 groups. After exposure to high water temperature, lower GM diversity and increased gene expression of inflammatory intestinal cytokines were observed for both inclusions (D0 vs. D1000) compared to groups in standard condition. However, the gene up-regulation involved a limited number of cytokines showing the absence of a substantial inflammation process able to compromise the functional activity of the intestine. Despite further study should be conducted to fully clarify this mechanism, cytokines up-regulation seems to be concomitant to the reduction of the GM diversity and, particularly, to the reduction of specific lactic acid bacteria such as Leuconostoc. The application of the microencapsulate blend tested can be a useful strategy to improve growth and feed utilization in rainbow trout under normal temperature conditions. According to the results organic acids and nature-identical compounds did not revert the effects triggered by the increased temperature of water.

Strategic supplementation of Flemingia silage to enhance rumen fermentation efficiency, microbial protein synthesis and methane mitigation in beef cattle.

BACKGROUND: Good quality protein as an on-farm feed resource has been in great demand to support the productivity of ruminants. A digestion trial using beef cattle crossbreds was conducted to assess the four dietary treatments of Flemingia macrophylla silage (FMS) supplementation at 0, 0.2, 0.4 and 0.6 kg dry matter (DM)/day in a 4 × 4 Latin square design. Feed DM intakes were measured during the 14 days and sample of feeds, feces, urine, as well as rumen fluid and blood were collected during the 7 days while the animals were on metabolism crates. RESULTS: Based on this experiment strategic supplementation of FMS increased (P < 0.05) nutrients digestibility (organic matter, crude protein, and acid detergent fiber) enhanced rumen total volatile fatty acid production especially propionic acid (C3), C2:C3 ratio while, remarkably promoted the microbial protein synthesis (MPS) by increasing N-balance and retention of purine derivatives. CONCLUSIONS: Under this experiment, the results revealed the potential use of FMS as a good-quality feed to improve nutrients digestibility, rumen fermentation, microbial protein synthesis, and to mitigate methane production. FMS supplementation at 0.6 kg DM/day exhibited the best result.

The effect of Saccharomyces cerevisiae live cells and Aspergillus oryzae fermentation extract on the lactational performance of dairy cows.

Eighty multiparous lactating Holstein cows (635 ± 33 kg) were used to study the effect of feeding Saccharomyces cerevisiae and/or Aspergillus oryzae on lactational performance for 14 weeks. Cows were assigned in a completely randomized experimental design, with repeated measures into four treatments, and were fed a basal diet of concentrates and forage at a ratio of 592:408, respectively. The treatments were: (1) the basal diet with no additive (Control treatment); (2) the basal diet supplemented with 3.5 g of live S. cerevisiae/cow daily (SC treatment); (3) the basal diet supplemented with 3.5 g A. oryzae fermentation extract/cow daily (AO treatment); and (4) the basal diet supplemented with 3.5 g of live S. cerevisiae + 3.5 g A. oryzae fermentation extract/cow daily (AOSC treatment). The AO and AOSC treatments increased (p < .05) feed intake and daily milk production, with a low milk fat content for the AO treatment. Feeding SC treatment decreased (p = .002) serum glucose concentration, while the AOSC treatment increased serum glutamate-oxaloacetate transaminase concentration. It is concluded that S. cerevisiae supplementation did not enhance milk production; however, A. oryzae fermentation extract improved feed intake and milk production.

Feeding value of rice distiller's dried grains with solubles as protein supplement in diet of laying hens.

A feeding trial of 10 weeks duration was undertaken on laying hens (n = 240) to evaluate feeding value of rice distiller's dried grains with soluble (rDDGS) with or without enzyme supplementation (α-amylase, ß-glucanase, xylanase, carboxymethylcellulase, pectinase, proteinase, α-galactosidase, ß-galactosidase, lipase, and phytase), following 4 × 2 factorial design, on egg production, nutrient utilization, and cost economics of egg production. The birds were randomly assigned to eight dietary treatments with 30 birds/treatment. The birds were housed individually in layer cages and each bird was taken as an experimental unit. Eight experimental diets were prepared by incorporating four levels (0, 50, 75, and 100 g/kg) of rDDGS with and without enzyme supplementation. The results revealed a significant (P < 0.01) increase of egg mass, feed intake, egg production, and body weight gain in dietary treatments with up to 75 g rDDGS though the values were statistically similar to the hens fed 100 g rDDGS. Enzyme supplementation resulted in significant (P < 0.01) improvement of egg mass, egg production, feed conversion ratio (FCR) per dozen eggs, FCR per kilogramme egg mass, and net FCR. The significantly (P < 0.01) higher yolk index was observed at 100 g rDDGS level, while shell thickness improved significantly (P < 0.01) up to 75 g rDDGS level. No significant effect of rDDGS inclusion was observed on shape index, albumin index, and Haugh unit. Enzyme supplementation significantly improved the shell thickness and yolk colour of eggs. Nitrogen, calcium, and phosphorus retention and dry matter metabolizability did not show any significant treatment effects. There was significant (P < 0.01) reduction in feed-cost per kilogramme egg mass or per dozen eggs with the increased DDGS levels and dietary enzyme supplementation. It was concluded that rDDGS can be used up to 100 g/kg diet of laying hens along with enzyme supplementation for better productivity of layer hens.

Enhancing lactational performance of Holstein dairy cows under commercial production: malic acid as an option.

BACKGROUND: In Experiment 1 we studied the effect of malic acid addition at 0, 1, 2 and 3 mg g-1 dry matter (DM) feed on in vitro ruminal fermentation. In Experiment 2, the effect of supplementing malic acid on feed intake, digestion and milk production and composition of lactating cows was studied. 200 multiparous lactating Holstein dairy cows were randomly assigned to two treatments: a basal diet containing concentrate and roughage at 58:42, respectively, with no additive (control treatment) or supplemented with malic acid at 30 g per cow daily (malic treatment). RESULTS: In Experiment 1, malic acid inclusion at 3 mg g-1 DM decreased in vitro methane production by 33%. In Experiment 2, malic acid decreased (P < 0.01) nutrient intake and increased nutrient digestibility. Greater (P < 0.05) milk yields, energy-corrected milk yields and milk component yields were observed in cows supplemented with malic acid. Greater milk (feed) efficiency was observed with malic acid treatment compared with the control treatment. CONCLUSION: The results show that the inclusion of malic acid at 30 g daily in the diet of lactating cows enhanced the nutrient digestibility and increased the milk production as well as feed efficiency. © 2018 Society of Chemical Industry.

Minimal water volume for intensively producing male Siamese fighting fish (Betta splendens Regan, 1910).

Water volume is a key parameter affecting the individual rearing of male Siamese fighting fish (Betta splendens Regan, 1910). In this study, minimization of water volume was pursued by assessing growth, feed utilization, digestive enzyme activities, color coordinates, muscle quality, and carcass composition. One-month-old solid-red male fish (0.97 ± 0.01 g initial body weight) were distributed individually into glass aquaria with five alternative water volumes (100, 150, 200, 250, and 300 mL), comprising 15 fish per treatment (n = 15), over 8 weeks duration. No mortality of the reared fish was found during the study. Growth performance and feed utilization of the fish reared in 150 mL water were superior to the other treatments. The water volume significantly affected specific activities of the digestive enzymes (P Ë‚ 0.05), except for amylase, and no differences in enzyme activities were observed between fish reared in 150 and in 300 mL water. The preferred treatment maintained skin lightness (L*) and had the highest redness (a* and a*/b*) among the treatments. Protein synthesis (RNA concentration) and its turnover rate (RNA/protein ratio) and myosin and actin in muscle also benefited from this treatment. Carcass composition, in terms of moisture, crude protein, and crude ash, was maintained, but the amount of crude lipid fluctuated with water volume. Based on our experiments, the preferred minimal water volume for individual rearing of male Siamese fighting fish should be about 150 mL.

Comparison of silage and hay of dwarf Napier grass (Pennisetum purpureum) fed to Thai native beef bulls.

Both quantity and quality of forages are important in dry season feeding. Eight Thai native beef bulls were arranged in a Completely randomized design to evaluate dwarf Napier namely Sweet grass (Pennisetum purpureum cv. Mahasarakham) preserved as silage or hay on feed intake, digestibility, and rumen fermentation. The animals were fed with forage ad libitum supplemented with concentrate mixture at 1.0% of BW for 21 days; data were collected during the last 7 days. The results showed that there were differences (P < 0.05) between treatments in dry matter (DM) intake, DM digestibility, and ruminal pH, in which hay feeding gave enhanced feed intake and more favorable ruminal pH. Nevertheless, mean ruminal ammonia nitrogen, total volatile fatty acids (TVFAs), proportion of VFAs, bacterial and protozoal population, and blood urea nitrogen were similar (P > 0.05) in animals fed silage and hay. Sweet grass is better preserved as hay rather than silage.