Low Levels Of Supplementation Research Articles

Non-invasive ventilation treatment for patients with chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease (COPD) affects the lives of millions of patients worldwide. Patients with advanced COPD may require non-invasive ventilation (NIV) to support the resultant deficiencies of the respiratory system. The purpose of this study was to evaluate the effects of varying the continuous positive airway pressure (CPAP) and oxygen supplementation components of NIV on simulated COPD patients by using an established and detailed model of the human respiratory system. The model used in the study simulates features of advanced COPD including the effects on the changes in ventilation control, increases in respiratory dead space and airway resistance, and the acid-base shifts in the blood seen in these patients over time. The results of the study have been compared with and found to be in general agreement with available clinical data. Our results demonstrate that under non-emergency conditions, low levels of oxygen supplementation combined with low levels of CPAP therapy seem to improve hypoxemia and hypercapnia in the model, whereas prolonged high-level CPAP and moderate-to-high levels of oxygen supplementation do not. The authors conclude that such modelling may be useful to help guide beneficial interventions for COPD patients using NIV.

83 Effect of a Saccharomyces cerevisiae fermentation product on intake and digestion in young horses undergoing exercise training

Young growing horses subjected to exercise have greater dietary requirements than horses at maintenance necessitating the delivery of a more nutrient dense diet. Inclusion of a grain concentrate in the total daily ration achieves this goal but also may put the young horse at risk of digestive disorders and reduced forage utilization. As such, the objective of this study was to determine if a dietary S. cerevisiae fermentation product (SCFP; TruEquine C, Diamond V) could influence nutrient utilization in young horses being introduced to grain concentrate feed and if the response was dose dependent. Thirty Quarter horse yearlings (561 ± 15.8 d of age and 371 ± 24.4 kg BW) were adapted to a 14% CP grain concentrate feed (Nutrena SafeChoice Original formulated without microbial ingredients), fed at 1% of BW as fed to meet or slightly exceed nutrient requirements for yearling horses undergoing light to moderate work and allowed ad-libitum access to Coastal bermudagrass (Cynodon dactylon) hay (67.8% NDF) and fresh water. Horses were stratified by age, BW, and sex and randomly assigned to one of 3 levels of SCFP: 0, 46, or 92 mg/kg BW divided evenly and top-dressed onto the grain concentrate meal at 12 h intervals. After 14 d of adaptation, intake and total fecal production were measured overa 4-d period. Horses were housed in individual 3.7 × 3.7 m stalls and allowed 1 h of exercise in individual 3.7 × 7.4 m runs daily during the collection period. All statistical analyses were performed in SAS 9.4 using PROC MIXED with the model containing treatment and horse included as the random variable. There was no significant treatment difference for any measure of intake (P ≥ 0.33); forage DM intake averaged 6.14 kg/d, total DM intake averaged 9.60 kg/d, and total digestible organic matter intake averaged 4.97 kg/d. There was a tendency for improved DM digestibility (P = 0.09) with supplementation (56.3 and 56.8% for 46 and 92 mg/kg BW, respectively) compared with no supplementation (54.2%). Supplementation of SCFP resulted in no significant differences (P ≥ 0.15) in organic matter (OM) or NDF digestibility. There were no differences in any indicator of nutrient digestibility between the low and high level of SCFP supplementation. An observed tendency for improved DM digestibility with SCFP supplementation suggests further research is warranted.

Diet supplementation of organic zinc positively affects growth, antioxidant capacity, immune response and lipid metabolism in juvenile largemouth bass, Micropterus salmoides.

Znis an important trace element involved in various biochemical processes in aquatic species. An 8-week rearing trial was thus conducted to investigate the effects of Zn on juvenile largemouth bass (Micropterus salmoides) by feeding seven diets, respectively, supplemented with no Zn (Con), 60 and 120 mg/kg inorganic Zn (Sul60 and Sul120), and 30, 60, 90 and 120 mg/kg organic Zn (Bio30, Bio60, Bio90 and Bio120). Sul120 and Bio120 groups showed significantly higher weight gain and specific growth rate than Con group, with Bio60 group obtaining the lowest viscerosomatic index and hepatosomatic index. 60 or 90 mg/kg organic Zn significantly facilitated whole body Zn retention. Up-regulation of hepatic superoxide dismutase, glutathione peroxidase and catalase activities and decline of malondialdehyde contents indicated augmented antioxidant capacities by organic Zn. Zn treatment also lowered plasma aminotransferase levels while promoting acid phosphatase activity and hepatic transcription levels of alp1, acp1 and lyz-c than deprivation of Zn. The alterations in whole body and liver crude lipid and plasma TAG contents illustrated the regulatory effect of Zn on lipid metabolism, which could be possibly attributed to the changes in hepatic expressions of acc1, pparγ, atgl and cpt1. These findings demonstrated the capabilities of Zn in potentiating growth and morphological performance, antioxidant capacity, immunity as well as regulating lipid metabolism in M. salmoides. Organic Zn could perform comparable effects at same or lower supplementation levels than inorganic Zn, suggesting its higher efficiency. 60 mg/kg supplementation of organic Zn could effectively cover the requirements of M. salmoides.

Supplementation of Cereal Proteins with Amino Acids: V. Effect of Supplementing Lime-Treated Corn with Different Levels of Lysine, Tryptophan and Isoleucine on the Nitrogen Retention of Young Children

A lime-treated corn diet was supplemented with two levels each of lysine and of tryptophan, as well as two levels of isoleucine with a constant lysine and tryptophan supplement. Comparison of corn protein with the FAO reference protein indicates tryptophan to be the first limiting amino acid and lysine the second. In 18 3-day balance periods in two children lysine supplementation alone somewhat improved nitrogen balance, but tryptophan addition had no effect. Analysis of 12 3-day balance periods in 4 children indicated that the addition of lysine to give 180 mg/g N in the diet (0.30% l-lysine·HCl) and of tryptophan to a total of 75 mg/ g N (0.28% dl-tryptophan) approximately doubled the percentage of nitrogen retention compared with the results when the basal diet was fed. Increasing the lysine to 270 mg/g N (0.56% l-lysine·HCl) or the tryptophan to 90 mg/g N (0.35% dl-tryptophan) either singly or together, did not improve significantly the nitrogen balance compared with that obtained with these amino acids at the lower levels of supplementation. The addition of isoleucine to 270 mg/g N (0.45% dl-isoleucine) to the 270 mg lysine/g N plus 25 mg tryptophan/g N resulted in a slightly higher nitrogen balance. The addition of isoleucine to a level of 225 mg/g N gave an intermediate value for nitrogen retention. None of the amino acid combinations used to supplement corn-masa resulted in as high nitrogen retention as those obtained from feeding isonitrogenous levels of milk. The variable results with supplementation of different cereals with essential amino acids to the level in the FAO reference protein provide further evidence that reference amino acid patterns should include both upper and lower limits for the amount of each amino acid per gram of nitrogen and specify the range of protein intake over which they apply.

Bacillus Swezeyi B2 Strain: A Novel Alkaliphilic Bacterium Producer of Alkaline-, Thermal, Oxidant-, and Surfactant-Stable Protease, Extremely Efficient in Detergency.

Proteolytic enzymes that are currently used to meet industrial demand are usually derived from Bacillus species. They find multiple technical applications, particularly they have been increasingly used as a key bio-additive in detergents. In this study, a novel alkalophilic bacterium was isolated from contaminated soil, exhibiting 1400U/ml proteolytic activity, and identified as Bacillus swezeyi B2. The crude enzyme likely contained a single extracellular protease. This enzyme revealed optimum activity at pH 10 and 70°C and was highly alkaline thermostable (7-12.5) and up to 70°C. The protease activity was completely inhibited by Phenylmethylsulfonyl fluoride (PMSF) suggesting that it belongs to the serine protease group. It was highly stable in the presence of the strong anionic surfactant (SDS) and oxidizing agents (H2O2). The supernatant was lyophilized and showed high storage stability retaining 100% of its original activity after one year of conservation at 4°C. The lyophilized product was evaluated for its detergent efficacy, it revealed excellent compatibility with various laundry detergents keeping its full original activity after incubation for 1h with seven solid and liquid commercial detergents and it effectively removed chocolate stains at low washing temperature (40°C) and low supplementation level (125U/ml). The features of this single alkaline and thermotolerant protease, stable toward surfactants, oxidizing agents, and commercial detergents with stain removal efficacy support its ideal choice for supplementation in detergent formulations.

Effects of immunocastration and supplementary feeding level on the performance and blood biochemical markers of farmed yearling fallow deer (Dama dama).

In cervids, blood biochemical markers may reflect changes in various physiological and environmental factors, especially in response to changes in metabolism following nutrient supplementation or the manipulation of hormone production. Decreasing androgen production through immunocastration (IC) to ease the husbandry of male animals is currently a more ethically acceptable method than physical castration, but its commercial use is unexplored in fallow deer. Forty yearlings male fallow deer were grouped into four treatment combinations: IC on high (200 g commercial pellets + 600 g concentrate mixture of 90% oats and 10% wheat grains) or low (100 g commercial pellets + 300 g concentrate mixture of 90% oats and 10% wheat grains) level of feed supplementation, or noncastrated bucks on a high or low level of feed supplementation. Immunocastrated animals were vaccinated at the start of the study (Week 1) and again during Week 3 of the study. Diet affected all body growth parameters (slaughter weight, daily gain, carcass weight, dressing percentageand body condition score). Fallow deer from all treatments showed increasing concentrations of fat and energy blood biochemical markers over the study period, including plasma glucose(GLU)and triglyceride(TRIG), and decreased cholesterol(CHOL) and lipase(LIPA) concentrations. The higher level of supplementary feeding decreased plasma albumin(ALB) and creatinine (CREA), and increased globulin(GLOB) concentrations. On the other hand, IC and lower-level supplementation reduced growth performance. Overall, IC may be an interesting tool for welfare management of yearling stags for slaughter; however, the advantage appears to only be in well-fed animals, as low-level of feeding can further reduce growth performance in immunocastrated animals. Further studies should evaluate the carcass performance of animals under similar treatment conditions to ascertain the effects on muscle and fat yields.

Effects of feeding Zinc oxide at low supplementation level on the properties of manure and compost in Sow Farms

Effects of feeding Zinc oxide at low supplementation level on the properties of manure and compost in Sow Farms

PSIII-1 Impact of low Levels of Tannin Supplementation on Enteric Methane Emissions and Performance in Organic Dairy Heifers

Abstract Condensed tannins are theorized to reduce enteric methane emissions by enhancing protein efficiency and decreasing ruminal fiber fermentation in ruminant animals. The objective of this study was to assess the viability of supplemented condensed tannins fed at increasing levels: 0% (CON), 0.075% (LOW), 0.15% (MED), and 0.30% (HIG) of dry matter intake (DMI). The study acclimation utilized 24 organic Holstein heifers, one GreenFeed emission measurement system, two SmartFeed Pro systems (C-Lock Inc., Rapid City, SD), and individual animal feeding stanchions. Twenty organic Holstein heifers (BW = 218.75 ± 16.78 kg) were selected based on acclimation and were stratified into treatment groups based on initial body weight and acclimation status. A 7-d covariate gas analysis was performed prior to the study to account for individual animal emission differences. Daily, heifers were offered 1 kg of starter calf feed and tannin in the individual feeding stanchions for 45-d and fed a basal TMR diet through the SmartFeed Pro systems. Statistical analysis was conducted in R with the fixed effect of treatment and pre-trial emission rate as a covariate. Daily methane production ranged from 141 to 152 g methane (CH4)/day between treatments. No significant difference was observed between treatments for daily methane production (P=0.53), methane yield (g CH4/ kg DMI; P=0.82), or emission intensity (g CH4/kg of body weight gain; P=0.62). Similarly, a treatment effect was not observed for DMI (P=0.95), average daily gain (ADG) (P=0.50), or feed efficiency (P=0.36). However, DMI and ADG continued to increase throughout the study, suggesting that the supplemental tannin did not negatively impact animal performance. The results of this study would not indicate that low levels of tannin supplementation alter CH4 emissions in organic Holstein heifers.

Brown Algae Fucus vesiculosus in Pasta: Effects on Textural Quality, Cooking Properties, and Sensorial Traits.

Fucus vesiculosus is a brown seaweed rich in iodine, fucoxanthin, and phlorotannins, all known to be bioactive compounds associated with health-promoting events. The enrichment of a staple food such as pasta with seaweed flour, could convey health benefits without changing eating habits. In this work, F. vesiculosus flour (FVF) was incorporated into durum wheat pasta at 1, 5.5, and 10% gradient levels. The pasta enriched with FVF needed additional water during dough formation and required more cooking time, resulting in higher weight gain but also increased cooking loss (observed with 5.5 and 10%). The fracturability of raw pasta decreased for all the FVF pasta, though the cooked firmness and hardness were only affected with the inclusion of 10% FVF. The substitution of wheat semolina with FVF at a 10% level caused an increase in the pasta’s fiber content, which resulted in a more discontinuous protein–matrix structure, as observed at the microscopic level. Untrained consumers were very positive about the overall sensory traits of the pasta with low supplementation levels (1 and 5.5%). About 72% of panelists selected the 1% FVF pasta as their favorite sample. The utilization of FVF in pasta should be targeted at low inclusion levels to cope with the expected texture quality and prevent the impairment of the sensory traits.

PSIII-19 Soil nutrient profile from cool-season forages fertilized with manure from steers supplemented with titrated levels of dried distillers grains

Abstract Dried distillers grains with solubles (DDGS) is commonly used as supplemental feed in cattle rations. However, the systemic effects of overfeeding DDGS, especially to potential fertilizer benefits of pass-through nitrogen, are widely unknown. Therefore, our objective was to evaluate plant and soil response to fertilization with manure from steers supplemented with titrated levels of DDGS. Manure utilized was collected from steers supplemented with DDGS (0%, 0.25%, 0.5%, and 1% BW) during a 2-yr experiment. The experimental design was a randomized complete block design with an augmented factorial treatment structure wherein benches represented blocks. The factorial was made up of manure treatment (0, 0.25, 0.5, or 1% BW DDGS, chemical fertilizer, or none) soil type (Windthorst or Purves), and plant species (none, crimson clover, or rye). Pots were sown (5 seeds/pot) and grown in a greenhouse for 35 d. Water was applied daily at 90% evapotranspiration. After harvest, soils were sifted, dried for 72 h at 55°C, then assayed for C, N, NO3-N, P, K, Ca, Mg, Na, and S. There was an interaction of manure and soil type for soil C (P < 0.01). Purves soils amended with any manure had a greater (P < 0.05) concentration of C (1.8%) than did the negative control (1.3%). From Windthorst, soil C was greatest from 1% BW DDGS manure (1.9%), and least from 0% DDGS manure (1.5%), with 0.25 and 0.5% manures and the negative control intermediate. There was an interaction of manure, soil type, and forage for soil N (P < 0.01). Manures with higher levels of supplementation had greater (P < 0.05) soil N than lower levels of supplementation or the negative control. Legumes had greater soil N than grasses. Results are interpreted to mean that moderate supplementation of steers with DDGS may yield soil nutrient benefits through nutrient deposition.

Mitigation of AFB1-Related Toxic Damage to the Intestinal Epithelium in Broiler Chickens Consumed a Yeast Cell Wall Fraction.

In vivo experiments were conducted to evaluate the effectiveness of a yeast cell wall fraction (YCW) to reduce the negative impact of aflatoxin B1 (AFB1) to the intestinal epithelium in broiler chickens. Zeta potential (ζ-potential), point of zero charge (pHpzc), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) techniques were used to characterize the YCW. Two hundred one-day-old male Ross 308 broiler chickens were randomly allocated into four treatments: (1) control, chickens fed an AFB1-free diet; (2) AF, chickens feed an AFB1-contaminated diet (500 ng AFB1/g); (3) YCW, chickens fed an AFB1-free diet + 0.05% YCW; and (4) AF + YCW, chickens fed an AFB1-contaminated diet (500 ng AFB1/g) + 0.05% YCW. At the end of the 21-day feeding period, fluorescein isothiocyanate dextran (FITC-d) was administered to chicks by oral gavage to evaluate gastrointestinal leakage. Blood and duodenum samples were collected to assess serum biochemistry and histomorphology, respectively. Compared to the control group, chicks of the AF group significantly diminished weight gain (WG) and average daily feed intake (ADFI), and increased feed conversion ratio (FCR), mortality rate (MR), and intestinal lesion scores (p < 0.05). Alterations in some serum biochemical parameters, and damage to the intestinal integrity were also evident in the AF-intoxicated birds. YCW supplementation improved WG and FCR and increased villus height, villus area, crypt depth, and the number of goblet cells in villi. The effects of YCW on growth performance were not significant in chicks of the AF + YCW group; however, the treatment decreased MR and significantly ameliorated some biochemical and histomorphological alterations. The beneficial effect of YCW was more evident in promoting gut health since chickens of the AF + YCW group presented a significant reduction in serum FITC-d concentration. This positive effect was mainly related to the changes in negative charges of YCW due to changes in pH, the net negative surface charge above the pHpzc, the higher quantities of negative charged functional groups on the YCW surface, and its ability to form large aggregates. From these results, it can be concluded that YCW at low supplementation level can partially protect broilers' intestinal health from chronic exposure to AFB1.

Effects of supplementary feeding level on digestion and energy utilization by sheep and goats grazing arid-area rangelands

An experiment was implemented to examine differences between sheep and goats in the utilization of open arid-area rangelands when provided with different concentrate supplement levels. Fifty-two non-lactating females (Abu-duleik sheep, n = 26 and Balady goats, n = 26) were employed in a 90-day experimental period. Animals of each species were allocated randomly into two treatments, according to a 2 × 2 factorial arrangement, with animal species (goats and sheep) and concentrate level (low and high) as main factors. They were grazing widely over the arid-area rangelands with a limited amount of a concentrate supplement, low (1 % BW) or high (2 % BW) (DM basis). Total energy expenditure was estimated by heart rate (HR) monitors for 48 h after its calibration by oxygen consumption with a face mask open-circuit respiratory system. However, the significant interaction between animal species and concentrate levels of supplement indicated that increasing the concentrate level had a negative effect (P < 0.05) on forage intake (22.8 vs. 17.0 ± 1.58 g/ kg BW, for goats supplemented with low or high concentrate level, respectively) and digestibility by grazing goats. The reduction in goat’s digestibility was mainly attributed to the reduction (P < 0.01) in fiber fraction digestibility (546 vs. 441 ± 24.0 g/ kg dry matter intake, respectively). The contrary was observed in sheep in which the greatest forage consumption and digestibility were observed in grazing sheep supplemented with a high concentrate level, including the fiber fraction digestibility. Total energy expenditure was similar between sheep and goats when supplemented with a low concentrate level (600 and 574 ± 24.6 kJ/ kgBW0.75, respectively), while it was significantly (P < 0.01) greater for sheep than for goats when supplemented with a high level (776 vs. 577 ± 24.6 kJ/ kg BW0.75, respectively). This was reflected in the energy balance (EB) that was negative and similar in sheep and goats at a low supplementation level (−55.2 and −64.3 ± 14.27 kJ/ kg BW0.75, respectively, while sheep reported positive (P < 0.05) and greater EB than that of goats with a high level (71.5 vs. 2.7 ± 14.27 kJ/ kg BW0.75, respectively). In conclusion, concentrate supplement is necessary to maintain animals without nutritional deterioration while grazing in the open arid-area rangelands, however, its effects on the ability to utilize a low quality forage differed between sheep and goats at a high supplementation level.

Influence of vitamin coupled with micronutrient supplement on the biomethane production, process stability, and performance of mesophilic anaerobic digestion

Batch anaerobic digestion (AD) using municipal solid waste (MSW) as a substrate with anaerobic sludge as inoculum were carried out under mesophilic conditions to understand the effect of Vitamin supplement coupled with micronutrients on the AD process. Reactions were operated using various concentrations of vitamin and water-based metal supplementations. The stability and process performance in the low level supplementation was indicated by evaluating Volatile fatty acids to alkalinity ratio, pH as well as methane kinetics. The feasibility of AD process was further evaluated by cost-benefit ratio analysis. This study shows that Vitamin addition as a sole supplement had either no significant or negative effect on methane production and process performance of anaerobic digestion (AD). However, coupling the metal supplement with vitamins shows an increase in methane production up to 30% compared to sole vitamin supplement and control systems. This study also shows that high levels of metal supplementation were detrimental and 15% decline in methane production over the control system was observed in high concentrations. Low level addition improved the reactor performance and process stability. Moreover, cost/benefit ratios lower than 1 were achieved for these concentrations. Hence, low levels of vitamin and water-based metal supplementation at 0.5–5 mg/L, increased the methane production and process stability by approximately 15, and 25% respectively.

A review on insect meals in aquaculture: the immunomodulatory and physiological effects

The depletion of global fishery stock has posted significant effects to the world capture fishery industry. Constant environmental issues and fluctuation of fish meal (FM) costs have pushed the aquafeed industry to seek for alternative protein sources to sustain the huge demand of feed in aquaculture production. Insect meal (IM) has already started to gain global attention as an alternative for FM replacement. Substantial feeding trials have revealed its promising application not only beneficial as in protein replacement but also playing a vital role as a functional ingredient that boosting immunostimulatory effects in a wide range of aquatic animals. Here, we compiled and categorized several major groups of insects, for example black soldier fly, yellow mealworm, housefly, silkworm, alongside a minor group of insect species widely used as the alternative diet in aquaculture. Critically, we discuss the functional properties of the IMs, their immunomodulatory, and physiological effects in aquatic species. Biological parameters include oxidative stress, serum biochemical, hematological parameters, and immune-related genes are also further discussed in this review. In short, we suggest that low levels of IM supplementation could improve survival, immunity, and feed conversion efficiency of targeted aquaculture species. Chitin and its derivatives alongside active substances in insect exoskeleton, such as antimicrobial peptides (AMPs) play an essential role in the immunomodulation of aquatic organisms. Knowledge of this area is still in infancy. Therefore, it is a critical need to further address the mechanism of immunomodulation focusing on the isolated components from IMs.

Economic evaluation from beef cattle production industry with intensification in Brazil's tropical pastures.

This study aimed to evaluate different scenarios (year, supplementation level) about economic results of beef cattle production during rearing and finishing phase in Brazilian's tropical pastures. Four scenarios were evaluated in combination with fourteen supplements, and it was originated from some research developed inside Forage Crops and Grasslands section from São Paulo State University among years 2011 and 2014. The economic evaluation was analyzed by operating cost, total operational costs, gross revenue, operating profit, and financial net income. Besides profitability, internal rate of return (IRR), benefit/cost ratio (B:C), and simple payback period (SPP) were calculated too. During rearing phase, the best result was observed for scenario 2 (2012), supplement 3.2 (mineral mix) with values of 11 cycles, 26.3%, 9.30%, and 0.39 for SPP, profitability, IRR, and B:C ratio, respectively. Already to finishing phase, the best scenario was 3 (2013), supplement 10 (multiple supplement with supplementation level equal 1.0% body weight), which obtained 4 cycles, 68.7%, 27.00%, and 2.34 for the same variables above mentioned. Results were consistent being that higher IRR and profitability occurred when using low supplementation level. Hence, the economic responses from different scenarios (years and supplements) can alter the final livestock farm financial statement.

Beef cattle responses to pre-grazing sward height and low level of energy supplementation on tropical pastures.

The objective of this study was to investigate the effects of energy supplementation and pre-grazing sward height on grazing behavior, nutrient intake, digestion, and metabolism of cattle in tropical pastures managed as a rotational grazing system. Eight rumen-cannulated Nellore steers (24 mo of age; 300 ± 6.0 kg body weight [BW]) were used in a replicated 4 × 4 Latin square design. Treatments consisted of two levels of energy supplementation (0% [none] or 0.3% of BW of ground corn on an as-fed basis) and two pre-grazing sward heights (25 cm [defined by 95% light interception (LI)] or 35 cm [defined by ≥ 97.5% LI]) constituting four treatments. Steers grazed Marandu Palisadegrass [Brachiaria brizantha Stapf. cv. Marandu] and post-grazing sward height was 15 cm for all treatments. Forage dry matter intake (DMI) was increased (P = 0.01) when sward height was 25 cm (1.86% vs. 1.32% BW) and decreased (P = 0.04) when 0.3% BW supplement was fed (1.79% vs. 1.38% BW). Total and digestible DMI were not affected by energy supplementation (P = 0.57) but were increased when sward height was 25 cm (P = 0.01). Steers grazing the 25-cm sward height treatment spent less time grazing and more time resting, took fewer steps between feeding stations, and had a greater bite rate compared with 35-cm height treatment (P < 0.05). Energy supplementation reduced grazing time (P = 0.02) but did not affect any other grazing behavior parameter (P = 0.11). Energy supplementation increased (P < 0.01) diet dry matter digestibility but had no effect on crude protein and neutral detergent fiber digestibilities (P = 0.13). Compared with 35-cm pre-grazing sward height, steers at 25 cm presented lower rumen pH (6.39 vs. 6.52) and greater rumen ammonia nitrogen (11.22 vs. 9.77 mg/dL) and N retention (49.7% vs. 20.8%, P < 0.05). The pre-grazing sward height of 25 cm improved harvesting efficiency and energy intake by cattle, while feeding 0.3% of BW energy supplement did not increase the energy intake of cattle on tropical pasture under rotational grazing.

Isoflavone supplementation, via red clover hay, alters the rumen microbial community and promotes weight gain of steers grazing mixed grass pastures.

Biochanin A, an isoflavone present in the pasture legume red clover (Trifloium pratense L.), alters fermentation in the rumen of cattle and other ruminants. Biochanin A inhibits hyper-ammonia-producing bacteria and promotes cellulolytic bacteria and fiber catalysis in vitro and ex vivo. Consequently, biochanin A supplementation improves weight gain in grazing steers. Red clover contains biologically active isoflavones that may act synergistically. Therefore, the objective was to evaluate the effect of two levels of red clover hay on growth performance and the microbial community in growing steers grazing mixed grass pastures. A grazing experiment was conducted over 2 early growing seasons (2016 and 2017) with 36 cross-bred steers and twelve rumen-fistulated, growing Holstein steers for evaluation of average daily gain and rumen microbiota, respectively. Steers were blocked by body weight and assigned to pastures with one of four treatments: 1) pasture only, 2) pasture + dry distillers’ grains (DDG), 3) pasture + DDG + low level of red clover hay (~15% red clover diet), or 4) pasture + DDG + high level of red clover hay (~30% red clover diet). DDG were added to treatments to meet protein requirements and to balance total protein supplementation between treatments. All supplementation strategies (DDG ± red clover hay) increased average daily gains in comparison to pasture-only controls (P < 0.05), with a low level of red clover supplementation being the most effective (+0.17 kg d-1 > DDG only controls; P < 0.05). Similarly, hyper-ammonia-producing bacteria inhibition (10–100-fold; P < 0.05), fiber catalysis (+10–25%; P < 0.05) and short chain fatty acid concentrations were greatest with the low red clover supplement (+~25%; P < 0.05). These results provide evidence that lower levels or red clover supplementation may be optimal for maximizing overall microbial community function and animal performance in grazing steers.

Low levels of protected ascorbic acid improve broiler chicken performance after long fasting on housing

Ascorbic acid is involved in many essential functions in broiler chickens. Vitamin C has been used as a supplement in broiler chicken diets with the objective of improving performance characteristics, especially under stressful situations. The aim of this work was to evaluate the effects of low levels of ascorbic acid supplementation on performance, the relative weight of organs and the mitochondrial metabolism of liver cells in broiler chickens after a delay in housing conditions. Eight hundred thirty-two one-day-old male Cobb 500 chicks were used in a randomised study with 4 treatments (0, 2.5, 5 and 10 mg/kg of encapsulated ascorbic acid dietary supplementation during the prestarter stage of development) with 8 replicates. Feed intake (FI), body weight gain (BW gain), feed conversion ratio (FCR), viability, liver O2 respiration and the mass and relative weights of organs were measured. Our results demonstrated that dietary supplementation with ascorbic acid had a beneficial effect on characteristics such as BW gain and FCR in the initial phase. These data indicate that the use of polyethoxylated ascorbic acid in the diets of broiler chickens during the prestarter stage can improve their performance when there is a delay in housing the animals.

Comparative Slaughter Performance and Meat Quality of Rutana, Gumuz and Washera Sheep of Ethiopia Supplemented with Different Levels of Concentrate

A study was conducted to compare the carcass yield and meat quality of Rutana, Gumuz and Washera sheep of Ethiopia under two concentrate supplement levels (CSL), low (300 g/day) and high (450 g/day). The supplement contains 45% wheat bran, 26% maize grain and 29% Noug cake. A total of 36 sheep (12 from each genotype) were used in 3 × 2 factorial treatment arrangement (3 genotypes and 2 CSL) which was used in a completely randomized block design. Hay was fed ad libitum at a rate of 20% refusal. After the completion of 90 days fattening period, all sheep were slaughtered and meat sample from longissimus dorsi muscle of each animal was taken for sensory evaluation and instrumental measurement of tenderness and for color, pH, and chemical composition analysis. Slaughter body weight (SBW) (26.0 vs. 24.1 kg), hot carcass weight (HCW) (11.3 vs. 9.7 kg), dressing percentage (DP) on SBW (43.4% vs. 40.1%) and EBW basis (53.6% vs. 50.9%), and rib eye-muscle (REM) were higher for the high than low CSL. Rutana sheep had heavier HCW (11.9 kg) than Gumuz (10.1 kg) and Washera (9.4 kg) sheep. DP on EBW basis was higher for Rutana (54.7) than Washera sheep (48.1), while the value for Gumuz (50.9) was similar with both genotypes. Meat from high supplemented sheep had higher fat (9.7% vs. 8.8%), tenderness, juiciness, flavor and lower shear forces than the low level of supplementation. Most sensory parameters measured were in the order of Rutana > Gumuz > Washera sheep. It is concluded that Rutana sheep were relatively more suitable than Gumuz and Washera sheep for production of better carcass yield. The potential of Washera sheep to produce more carcass yield relative to their HCW, SBW and EBW was comparable with that of Gumuz sheep.

Macroalga-Derived Alginate Oligosaccharide Alters Intestinal Bacteria of Atlantic Salmon

Prebiotics are substrates intended to sculpt gut microbial communities as they are selectively utilized by the microorganisms to exert beneficial health effects on hosts. Macroalga-derived oligosaccharides are candidate prebiotics, and herein, we determined the effects of Laminaria sp.-derived alginate oligosaccharide (AlgOS) on the distal intestinal microbiota of Atlantic salmon (Salmo salar). Using a high-throughput 16S rRNA gene amplicon sequencing technique, we investigated the microbiota harbored in the intestinal content and mucus of the fish offered feeds supplemented with 0.5 and 2.5% AlgOS. We found that the prebiotic shifts the intestinal microbiota profile; alpha diversity was significantly reduced with 2.5% AlgOS while with 0.5% AlgOS the alteration occurred without impacting the bacterial diversity. Beta diversity analysis indicated the significant differences between control and prebiotic-fed groups. The low supplementation level of AlgOS facilitated the dominance of Proteobacteria (including Photobacterium phosphoreum, Aquabacterium parvum, Achromobacter insolitus), and Spirochaetes (Brevinema andersonii) in the content or mucus of the fish, and few of these bacteria (Aliivibrio logei, A. parvum, B. andersonii, A. insolitus) have genes associated with butyrate production. The results indicate that the low inclusion of AlgOS can plausibly induce a prebiotic effect on the distal intestinal microbiota of Atlantic salmon. These findings can generate further interest in the potential of macroalgae-derived oligosaccharides for food and feed applications.