Reduced Feed Conversion Ratio Research Articles

Evaluation of dried porcine solubles in diets of Rice field eel (Monopterus albus)

Porcine solubles, originating from porcine mucosal tissues, is a by-product of heparin production. The nutritional value and functionality of a carrier-free, spray-dried porcine soluble (DPS) product was evaluated in 56-day experiment with juvenile rice field eel Monopterus albus (initial weight: 15.5 ± 0.19 g) fed diets with optimal (42%) and a low level (22%) of fishmeal (FM) inclusion. Six isonitrogenous and isolipidic experimental diets were formulated with two levels of FM (22% and 42%) and three levels of DPS (0%, 2.5% and 5%). Growth performance, humoral immunity, digestive enzyme activities, intestinal histology and expression of intestinal tight junction protein-related mRNA were analyzed at the end of the trial. Similar to FM, inclusion of 5% DPS significantly enhanced growth rate and reduced feed conversion ratio of rice field eel, although no significant interaction between FM and DPS on growth performance were observed. Positive influences of DPS on fish health and immunity were seen in that inclusion of DPS significantly enhanced serum complement (C3, C4), immunoglobulin M (IgM) levels and lysozyme activities, and altered total cholesterol and triglyeride contents in the serum of rice field eel. In regard to gut health, villus height, goblet cell quantity and expression of ZO-1 transcripts significantly (P < 0.05) increased with DPS inclusion in fish fed low-FM diets but was not observed in fish fed diets containing the optimal level of fishmeal. Expression of ZO-2 and CL-12 transcripts in intestine also was significantly (P < 0.05) elevated by DPS inclusion in fish fed diets containing low or optimal FM. Moreover, FM and DPS showed significant (P < 0.05) interactions in the expression of inflammatory cytokines mRNA in the intestine of rice field eel with 5% DPS inclusion significantly (P < 0.05) promoting the expression of Tgfb2 and IκBe mRNA, while repressing IL-1β, IL-8, IL-12 and IFNγ expression in fish fed diets containing low FM. This study is the first to show functionality of DPS supplementation at 5% of diet in any aquatic species. Based on these results, DPS supplementation should be considered as an effective, innovative and sustainable strategy to improve health, as well as reduce intestinal inflammation and maintain normal intestine structure of rice field eel fed low-FM diets.

Performance of Eimeria-challenged male broilers fed 2 ionophore–nicarbazin combinations

Summary This study assesses the efficacy of 2 different potentiated ionophores (monensin and narasin) and a chemical (nicarbazin, a shuttle) in program with narasin to control coccidiosis in challenged male broilers through the evaluation of performance and macroscopic lesions of internal organs. A total of 4,400 broiler chicks were housed in 44 floor pens of 100 birds each; birds of the first group were fed a narasin/nicarbazin (NN)–containing diet from 0 to 27 D of age followed by narasin diet until market age, and those of group 2 were fed a monensin/nicarbazin diet followed by narasin ration for the same trial periods. The coccidia challenge was performed at day 1 by the inclusion of a proven Eimeria-infected litter in the bedding of all floor pens followed by an oral challenge using a commercial cocci vaccine at 7 D of age with a concentration of 11 times the vaccine dose. Although results showed that NN and monensin/nicarbazin treatments both demonstrated efficacy at reducing coccidian lesions, NN significantly increased BW and reduced feed conversion ratio (P

Effect of Lactobacillus Casei and Lactobacillus acidophilus in Laying Hens Challenged by Escherichia coli Infection

This study aimed to prove the potential of Lactobacillus casei and Lactobacillus acidophilus probiotics as alternative substitutes of antibiotic growth promoters in laying hens challenged by Escherichia coli infection in order to enhance their growth performance and hen day production. The study used a total of 120 laying hens aged 25 weeks, divided into 3×2 treatments with each comprising 4 replications, and each replication consisted of 5 hens. The study used a completely randomised factorial design; factor a was the feed additive (control, antibiotics growth promoters /AGP, probiotic), whereas factor b was the E. coli infection (non-infection and E. coli infection). The results showed that there were significant differences (p<0.05) between the treatment of feed additive (factor a), and E. coli infection (factor b), and interaction (p<0.05) between the feed and the infection for the egg weight, hen day production, feed conversion ratio and feed efficiency. The probiotic use of 0.5% L. casei + 0.5% L. acidophilus in hens either infected or uninfected with E. coli still produced the highest egg weight, hen day production, feed efficiency and reduced feed conversion ratio compared to all treatments. Based on the results, it can be concluded that the use of probiotics 0.5% L. casei and 0.5% L. acidophilus act as alternative substitutes for antibiotic growth promoters in laying hens challenged by E. coli infection Keywords: E. coli; growth performance; hen day production; Lactobacillus acidophilus; Lactobacillus casei

Enhanced modulation of gut microbial dynamics affecting body weight in birds triggered by natural growth promoters administered in conventional feed.

This study explored the effects of natural growth promoters (phytogenic feed additives and organic acids) on animal performance, carcass characteristics, blood parameters, gut microflora composition, and microbe–host interactions in broiler chickens over a 42-day feeding period. Two-hundred-fifty-day-old chicks were randomly assigned to one of five treatments: (i) control diets (CON); (ii) control diets + 40 g/tons antibiotic growth promoter (AB); (iii) control diets + 3 kg/tons organic acids (ORG); (iv) control diets + 3 kg/tons phytogenic feed additives (PHY); (v) control diets + 3 kg/tons organic acids + phytogenic feed additive combination (COM). A non-significant differences (p > 0.05) were observed in broiler performance among treatments at 21 days of age; however, a gradually increasing body weight gain and reduced feed conversion ratio were observed at 42 days in treatments versus control group. Biochemical indices were non-significant (p > 0.05) except for decreased cholesterol (p < 0.05) and increased A/G ratio (p < 0.05) recorded in the treatment groups. The addition of PHY and ORG improved total counts of Enterococcus spp. and Lactobacillus spp. (p < 0.05) as well as reduced caecal and ileal Campylobacter spp. and Escherichia coli (p < 0.05). Correlation analysis elucidated beneficial bacteria (Enterococcus spp. and Lactobacillus spp.) were positively and pathogenic bacteria (Campylobacter spp. and E. coli) were negatively correlated (p < 0.05) with host weight gain. The findings indicated that dietary supplementation of PHY and ORG sustained balanced gut microflora, which in turn improved body weight. This study broadens the significance of using PHY and ORG as safe alternatives to antibiotic growth promoters for achieving healthier and economical broiler production.

β-glucan administration improves growth performance and gut health in New Zealand White and APRI rabbits with different breed responses.

This study investigated the effects of oral administration of β-glucan 1,3 (pharmaceutical grade 10%) on growth performance and carcass traits in two breeds of weanling rabbits adapted to survive in Egypt, New Zealand White (NZW) and Animal Production Research Institute (APRI) rabbits, with special attention to relative mRNA expression of interleukins and antioxidant enzyme genes, biochemical, and histological alterations. Oral administration of β-glucan with doses 0.25 and 0.5 ml per one-liter of drinking water significantly accelerated body weight gain (BWG) in both rabbits’ breeds, reduced total feed consumption (FC), and reduced feed conversion ratio (FCR), especially the 0.5 ml per one-liter dose in both rabbit breeds. There are remarkable differences in all the growth performance traits due to breed effect. The interaction effect between β-glucan and breed significantly improved BWG, FC, and FCR. There were non-significant differences in all carcass traits studied due to oral administration of β-glucan with both doses, except in dressing percentages. The highest of the dressing percentages were observed at doses 0.25 ml per one-liter (51%) and 0.5 ml per one-liter (52%) compared with control (50%). Our findings show significant variations in the final BW, total daily gain, feed consumption, and total feed conversion ratio between NZW and APRI rabbits. Absence of significant differences in the hot carcass weight and dressing percentage between the genetic groups had been reported in this study. Supplementing NZW and APRI rabbits with β-glucan increased blood total protein and globulin. The duodenal villi dimensions, splenic lymphoid diameter, muscular fiber diameter, and muscular glycogen areas were significantly increased by β-glucan administration. Expression of intestinal interleukin-18 (IL-18) in NZW rabbits treated with 0.25 and 0.5 doses of β-glucan was significantly upregulated and enhanced the immune response. β-glucan upregulated the expression of intestinal occludin mRNA particularly at dose 0.5 β-glucan as well as upregulated intestinal superoxide dismutase 1 (SOD1) and glutathione peroxidase 1 (GPx1), which modulates anti-inflammatory and antioxidant properties. In conclusion, oral administration of β-glucan at a dose of 0.25 or 0.5 ml per one-liter drinking water provided beneficial effects in the growth performance and health status of rabbits.

Dietary butyrate alone or in combination with succinate and fumarate improved survival, feed intake, growth and nutrient retention efficiency of juvenile Penaeus monodon

Organic acids and their salts have been used in commercial aquafeeds as an alternative to antibiotics, growth promoters and their effect on performance and survival continue to be investigated in aquatic organisms including shrimp with a few reports on Penaeus monodon. We assessed production performance and nutrient retention efficiency of juvenile black tiger shrimp fed diets supplemented without (control – CON) or with organic acids (butyrate - BUT, succinate – SUC, and fumarate - FUM) individually (10 g kg−1) or in combination (ALL; 30 g kg−1). After 42 days, survival was significantly higher in the BUT and ALL treatments compared to the CON (98% and 90% vs. 70%; P < .01). Addition of BUT, SUC, and ALL reduced feed conversion ratio compared to the CON group (1.3–1.7 vs. 2.4; P < .01). Biomass gain in BUT and ALL feeds was statistically higher than the rest of the dietary treatments (28.3 g vs. 11.2–19.1 g; P < .01). Non-linear and linear regressions displayed a strong relationship between biomass gain and total feed intake across dietary treatments with R2 varying from 0.71 to 0.99. The supplementation of SUC, BUT, and ALL increased the overall nutrient retention efficiency (RE) in comparison to the CON, with BUT and ALL displaying the highest RE for all tested macronutrients (e.g., crude protein = 26.7% and 24.6% vs. 15.3%, total lipid = 19.2% and 17.7% vs. 10.6%, ash = 25.1% and 23.1% vs. 12.1%, and gross energy = 17.7% and 16.3% vs. 10.2%). In summary, supplementation of ALL organic acids (fumarate, butyrate, and succinate) improved survival, feed intake, growth, and nutrient retention efficiency of juvenile P. monodon. Individually, BUT appears to be the most potent organic acid followed by SUC, whereas the use FUM isn't justified in P. monodon diets.

The effects and combinational effects of Bacillus subtilis and montmorillonite on the intestinal health status in laying hens

This study was conducted to evaluate the effects and combinational effects of Bacillus subtilis (BS) and montmorillonite (MMT) on laying performance, gut mucosal oxidation status, and intestinal immunological and physical barrier functions of laying hens. Three hundred sixty laying hens (29-week-old) were randomly assigned to a 2 × 2 factorial arrangement of treatments (n = 6) for 10 wk as follows: (1) basal diet; (2) the basal diet plus 5 × 108 cfu BS/kg; (3) the basal diet plus 0.5 g MMT/kg; and (4) the basal diet plus 5 × 108 cfu BS/kg and 0.5 g MMT/kg. Dietary supplementation with BS increased egg production and egg mass, the activities of catalase (CAT) and total superoxide dismutase in the intestinal mucosa, and villus height and villus height-to-crypt depth ratio of the jejunum (P < 0.05) but downregulated the mRNA expression levels of toll-like receptor 4 and myeloid differentiation factor 88 (MyD88) in the duodenum and jejunum, interleukin 1 beta in the duodenum, and nuclear factor kappa B P65 (NF-κB P65) and tumor necrosis factor alpha in the jejunum (P < 0.05). Dietary supplementation with MMT increased egg production and egg mass, the concentration of secretory immunoglobulin A in the duodenum, and the occludin mRNA expression level in the jejunum (P < 0.05) but reduced feed conversion ratio, malondialdehyde concentration in the duodenum and jejunum, and the mRNA expression level of MyD88 in the jejunum (P < 0.05). In addition, there was an interaction effect between BS and MMT supplementation on the CAT activity and the MyD88 mRNA expression level in the duodenum and the mRNA expression level of occludin in the jejunum (P < 0.05). In conclusion, dietary BS and MMT and their combination may improve the intestinal health status of laying hens, which may contribute to the increase in hens' laying performance.

The potential role of nano-selenium and vitamin C on the performances of Nile tilapia (Oreochromis niloticus).

Functional trace elements and vitamins can boost immunity and antioxidative response in aquatic animals without creating environmental hazards. While nano-selenium (Nano-Se) and vitamin C (VC) have been used as immunomodulators and antioxidants in animal and poultry feed, there is little data on Nano-Se and/or VC supplementation in aquatic animals. Thus, the current study evaluated the impact of adding Nano-Se and VC to the diets of Nile tilapia for 8weeks. Four diets were formulated and offered to the fish: no supplementation (control), 1mg Nano-Se/kg, 500mg VC/kg, and 1mg Nano-Se + 500mg VC/kg of food. Growth-related parameters (final body weight, weight gain, and specific growth rate) were significantly increased in tilapia fed Nano-Se and VC, with a reduced feed conversion ratio (P < 0.05). Intestinal villus length and width as well as the number of goblet cells were increased in tilapia fed Nano-Se and/or VC (P < 0.05). Additionally, dietary Nano-Se and/or VC significantly increased nitro-blue tetrazolium (NBT) level, superoxide dismutase, glutathione peroxidase, catalase, the phagocytic index, and lysozyme and phagocytic activities (P < 0.05). However, significantly reduced levels of malonaldehyde were observed in fish fed Nano-Se and/or VC (P < 0.05). TNF-α and IL-1β gene expressions in the liver and spleen of the fish were significantly upregulated by Nano-Se and/or VC (P < 0.05). The results revealed the potential role of Nano-Se and/or VC in enhancing growth, intestinal morphometry, and immune and antioxidative responses in Nile tilapia.

Optimal dietary curcumin improved growth performance, and modulated innate immunity, antioxidant capacity and related genes expression of NF-κB and Nrf2 signaling pathways in grass carp (Ctenopharyngodon idella) after infection with Aeromonas hydrophila

This study investigated the effects of dietary curcumin on growth performance, non-specific immunity, antioxidant capacity and related genes expression of NF-κB and Nrf2 signaling pathways in grass carp (Ctenopharyngodon idella). A total of 525 juvenile grass carps with mean initial body weight of (5.30 ± 0.10) g were randomly distributed into five groups with three replicates each, fed five diets containing graded levels of curcumin (0, 196.11, 393.67, 591.46 and 788.52 mg/kg diet) for 60 days. After feeding trial, fifteen fish per tank were challenged with Aeromonas hydrophila and the mortalities were recorded for 7 days. The results showed that optimal dietary curcumin (393.67 mg/kg diet) improved the weight gain (WG) and specific growth rate (SGR) of juvenile grass carp, reduced feed conversion ratio (FCR) and the mortalities after challenge (P < 0.05). Moreover, optimal dietary curcumin increased the activities of lysozyme (LYZ) and acid phosphatase (ACP), and complement 3 (C3) and C4 levels, decreased alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities in serum of grass carp after injection with A. hydrophila (P < 0.05). Meanwhile, optimal dietary curcumin up-regulated the mRNA levels of LYZ, C3 and antimicrobial peptides [hepcidin, liver-expressed antimicrobial peptide-2 (LEAP-2), β-defensin], and anti-inflammatory cytokines of interleukin-10 (IL-10) and transforming growth factor β1 (TGF-β1), and inhibitor of κBα (IκBα), whereas down-regulated pro-inflammatory cytokines of tumor necrosis factor-α (TNF-α), IL-1β, IL-6 and IL-8, and nuclear factor kappa B p65 (NF-κB p65), IκB kinases (IKKα, IKKβ and IKKγ) mRNA levels in the liver and blood of grass carp after injection with A. hydrophila (P < 0.05). In addition, optimal dietary curcumin increased the reduced glutathione (GSH) content and activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST) and glutathione reductase (GR), reduced reactive oxygen species (ROS) and malondialdehyde (MDA) levels in the liver of grass carp after injection with A. hydrophila (P < 0.05). Meanwhile, optimal dietary curcumin up-regulated the mRNA levels of these antioxidant enzymes and nuclear factor erythroid 2-related factor 2 (Nrf2), whereas down-regulated Kelch-like ECH-associated protein (Keap) 1a and Keap 1b mRNA levels (P < 0.05) in the liver and blood of grass carp after injection with A. hydrophila. Thus, optimal dietary curcumin supplementation could promote growth of juvenile grass carp, reduce FCR, and enhance disease resistance, innate immunity and antioxidant capacity of fish, attenuating inflammatory response. However, dietary excessive curcumin had negative effect on fish. Based on second-order regression analysis between dietary curcumin contents and weight gain, the optimum requirement of dietary curcumin in juvenile grass carp was determined to be 438.20 mg/kg diet.

Effects of Linseed Expansion on its Dietary Molecular Structures, and on Broiler Chicks Digestive Enzymes Activity, Serum Metabolites, and Ileal Morphology

SUMMARY Presence of various anti-nutritional factors such as mucilage, linatine, cyanogenic glycosides, and trypsin inhibitors in linseed has confined its usage as broiler feed ingredient. The objective of this study was to determine the effect of linseed, after a high-temperature, high-pressure expansion processing, on dietary anti-nutritional factors and nutrient molecular features. Further, an experiment was carried out in a completely randomized design with chicks fed either a control corn–soy diet or graded levels of expanded linseed (EL; 67, 135, and 203 g/kg). Each diet was fed to 8 groups of 15 chicks. Expansion of linseed increased live weight (LW) and reduced feed conversion ratio (FCR; g feed/g LW) considerably. EL incorporation in the diet of chicks increased digestive α-amylase, lipase, trypsin, and total alkaline protease activity. Incorporation of EL in the diet increased villi height and decreased crypt depth. Abdominal fat increased and pancreas weight decreased by inclusion of EL in diets. Gizzard and jejunum pH increased and duodenum pH decreased in chicks fed diets containing EL. The Fourier-transformed infrared spectroscopy showed only reduction in lipid to carbohydrates ratio in molecular structures. Positive correlation was found between FCR and α-helix to s-sheet ratio and carbohydrate-to-protein ratio. Increased s-sheet height reduced lipase activity, whereas an increased α-helix to s-sheet ratio increased lipase activity. The outcome of this study was that expansion was effective for improving the nutritional value of linseed for broiler chicks.

Data comparison of the effects of feeding ginkgo leaf fermentation and Chinese herbal medicine on meat ducks

In order to study the effect of feeding Ginkgo leaf fermentation and Chinese herbal medicine on meat duck, we added Ginkgo leaf fermentation and Chinese herbal medicine additive to the daily feed of meat ducks, and set up a control group (basic feed), a western medicine group (basic feed+150mg/kg aureomycin), an experimental group 1 (basic feed + Chinese herbal medicine 0.1%) and an experimental group 2 (basic feed + 0.1% Chinese herbal medicine + 2.5% Ginkgo leaf ferment). We fed the ducks for 45 days, and then completed the measurement of production performance and blood index. Based on the measurement method of related data, we used Excel and spss25 software for data statistics and analysis. The results showed that the diet supplemented with 0.1% Chinese herbal medicine and 2.5% Ginkgo leaf fermentation could significantly increase daily growth weight of meat ducks during the whole growth period (P<0.05), at the same time, it could reduce feed conversion ratio, and the content of total protein and albumin in serum could be significantly increased (P<0.05). The value of alkaline phosphatase in the experimental group was lower than that of the control group. The amount of immunoglobulin and complement in the serum were all higher in the experimental group than in the control group. The overall effect of Ginkgo leaf fermentation and Chinese herbal medicine in basic diet was significantly better than that of western medicine group (P<0.01).

Choline supplementation alters egg production performance and hepatic oxidative status of laying hens fed high-docosahexaenoic acid microalgae

The purpose of the current study was to investigate the effect of choline as a means of increasing docosahexaenoic acid (22:6 n-3, DHA) deposition in egg yolks of hens fed a high-DHA microalgae product. Fifty-six, 26-wk-old, White Leghorn hens were kept in individual cages and randomly allocated to 1 of 4 dietary treatments, each with 7 replicate groups of 2 hens (n = 7 per treatment). The experimental diets were corn and soybean meal based, with 0% microalgae (control), 1% microalgae and no additional choline chloride (Alg), and Alg plus choline chloride at 0.1% (Ch0.1) and 0.2% (Ch0.2). The feeding trial lasted 16 wk. The data were fit as a general linear mixed model to generate least square means in response to diet. Variables measured multiple times during the study were fit as repeated measures. Using orthogonal contrasts, Alg was compared to control, and Ch0.1 and Ch0.2 were compared separately to Alg. Ch0.1 increased hen day egg production (P < 0.05) and Haugh unit (P < 0.05), and reduced feed conversion ratio (P < 0.05) compared to Alg, but Ch0.2 did not. Alg increased egg DHA (P < 0.001), phosphatidylethanolamine (P < 0.05), and phosphatidylcholine (P < 0.001) compared to control, but Ch0.1 or Ch0.2 had no effect compared to Alg (P > 0.05). In the liver, Alg increased lipid peroxidation products compared to control (P < 0.01), and Ch0.1 reduced them compared to Alg (P < 0.01). Both Ch0.1 and Ch0.2 increased hepatic concentrations of γ- (P < 0.05; P < 0.001) and α-tocopherol (P < 0.01; P < 0.001), and Ch0.1 increased γ-tocopherol concentration in eggs compared to Alg (P < 0.05). The results from the current study suggest that supplemental choline chloride in hen diets containing microalgae can improve production performance and egg quality, and protect the liver from oxidative stress.

Emodin ameliorates metabolic and antioxidant capacity inhibited by dietary oxidized fish oil through PPARs and Nrf2-Keap1 signaling in Wuchang bream (Megalobrama amblycephala)

Dietary lipids and fatty acids are involved in cell metabolism and animal physiological regulation. However, oxidized lipids could induce oxidative stress and disorder normal growth and physiological health in fish. A 12-week rearing experiment with 6% fish oil (6F), 6% oxidized fish oil (6OF) and emodin supplemented diets (6F + E, 6OF + E) was conducted to evaluate the protective mechanism of emodin on oxidized fish oil stress in Megalobrama amblycephala. Results indicate that, under oxidized fish oil stress, emodin rescued the growth performance inhibition, improved special growth ratio (SGR), and reduced feed conversion ratio (FCR) and hepatosomatic index (HSI); rescued intestine histological impairment, ameliorated the structural expansion and membrane damage of mitochondria in intestine cells, and increased the length and intensity of intestinal villus. Moreover, emodin enhanced serum immune and antioxidant enzyme activity, increased metabolic activity through PPARs signaling, increased antioxidant capacity through PPARs and Nrf2-Keap1 signaling based on the transcriptional expression of specific genes. These results indicate emodin could be used as an effective immunostimulant to protect organism form oxidative stress induced by dietary oxidized lipid. This may provide insights for oxidized lipid prevention in aquaculture production.

Dietary vegetable oils inclusion on the performance, hormonal levels and hsp 70 gene expression in broilers under heat stress

The aim of the present study was to compare the effects of unsaturated and saturated oils on the performance, hormonal levels and hsp gene expression in broiler chickens exposed to heat stress. 300 one-day male broiler chicks were assigned to 4 treatments (Diets containing palm, corn, linseed or olive oils) with 5 replicates. At day 28 of age, 2 chickens were removed from each replicate, then blood samples and liver tissue samples were collected for analyses. Feeding linseed and olive oil reduced feed conversion ratio compared to corn and palm oils. The lowest level of insulin was for chickens fed linseed oil and corn oil. The highest level of corticosterone was found in chickens fed palm oil and the lowest level was for those received linseed oil. Chickens received linseed and corn oils had the highest levels of T3 and T4 and those fed palm and olive oils had the lowest levels. The highest HSP 70 gene expression was for chickens fed diet containing olive and linseed oils and the lowest one was for those fed corn and palm oils. It was concluded that olive oil and linseed oil could improve performance and heat tolerance of chickens under heat stress.

Efficacy of a Mono-Component Exogenous Protease in the Presence of a High Concentration of Exogenous Phytase on Growth Performance of Broiler Chickens

SUMMARY Increasing global population and disposable income is resulting in a dramatic rise in demand for animal-sourced food products. To meet this demand, the animal protein industry is constantly evolving to enhance efficiency and sustainability. Nutritionally, a major contributing technology to this objective is the exogenous feed enzymes. These enzymes can be included in the diet of livestock to improve digestibility, reduce nitrogen and phosphorus pollution, reduce diet cost, and improve uniformity of animal growth. However, the number of feed enzyme products on the market today is considerable and there is a lack of clarity as to how these divergent enzymes may interact in a diet. The study reported herein noted that the addition of a novel exogenous protease to a broiler chicken diet improved weight gain (+7.3%) and reduced feed conversion ratio (−4%) even though the diet already contained 2 other feed enzymes (phytase and xylanase). The results reported herein confirm the usefulness of exogenous protease and the value of such a part of a wider enzyme admixture to improve the sustainability of the broiler chicken industry.

Effects of elephant's foot (Elephantopus scaber) extract on growth performance, immune response, and disease resistance of nile tilapia (Oreochromis niloticus) fingerlings

Medicinal plant has been applied as an alternative strategy for antibiotics and chemotherapeutics for controlling the outbreak of diseases in tilapia farming. In this study, five doses of Elephantopus scaber extract (ESE) were added to the basal diet at 0, 2.5, 5, 10, and 20 g kg−1 feed of Nile tilapia fingerlings (13.92 ± 0.06 g initial weight) in triplicate. After 4- and 8- weeks post-feeding, fish were sampled to determine the effects of the ESE supplemented on fish's growth performance, humoral, and skin mucus immune response. After 8 weeks post-feeding, a challenge test against Streptococcus agalactiae was carried out using 10 fish from each tank. Fish fed ESE showed significantly increased serum lysozyme (SL), serum peroxidase (SP), alternative complement (ACH50), phagocytosis (PI), and respiratory burst (RB) compared to the control group (P < 0.05). The skin mucus lysozyme (SMLA) and skin peroxidase (SMPA) were stimulated in fish fed ESE diets. Dietary inclusion of ESE significantly (P < 0.05) promoted final body weight (FW), weight gain (WG), and specific growth rate (SGR); while a reduction in feed conversion ratio (FCR) was observed in fish fed 5 g kg−1 ESE, after 8 weeks post-feeding. The challenge study indicated that the relative percent survival (RSP) was 38.10%, 76.19%, 66.67%, and 47.62% in Diet 2, Diet 3, Diet 4, and Diet 5, respectively. Among the supplemented groups, dietary of 5 g kg−1 ESE showed significantly higher RPS and the highest resistance to S. agalactiae in comparison with other groups. In conclusion, supplementation of ESE (5 g kg−1) enhanced the humoral and mucosal immunity, promoted growth performance, and improved disease resistance of Nile tilapia against Streptococcus agalactiae.

Comparative effects of two phytases versus increasing the inorganic phosphorus content of the diet, on nutrient and amino acid digestibility in boilers

Comparative effects of graded doses of two phytases on growth performance, nutrient and amino acid (AA) digestibility were investigated in corn-soybean meal-based broiler diets. A negative control diet (NC) with low phosphorus (P) content (1.8, 4.4 and 2.5 g/kg retainable, total and phytate P respectively) was supplemented with four doses of a Buttiauxella sp phytase (analyzed activity of 303 to 1046 FTU/kg) or an E. coli phytase (analyzed activity of 442 to 1811 FTU/kg), and tested against three positive control diets comprising the NC + 0.6, 1.2 or 1.8 g P from monocalcium phosphate (MCP)/kg feed and increased Ca content (+0.8 g/kg). A total of 1152 male Ross 308 broilers at 5 days of age were assigned to 72 cages with 16 birds/cage and 6 cages/treatment were given free access to pelleted diets until 21 days of age. Feed intake (FI), body weight and mortality were recorded and used to calculate body weight gain (BWG) and feed conversion ratio (FCR) during 5–20 days of age. Excreta was collected on day 18–20 to determine total tract retention of nutrients. Tibias (from 4 birds pooled per cage) and ileal digesta (from all birds and pooled per cage) were sampled at 21 days of age to determine tibia ash, ileal digestibility of nutrients and AA. Compared to NC, increasing phytase dose and MCP levels produced a stepwise increase in FI, BWG and reduction in FCR. Increasing phytase dose produced curvilinear increases in BWG, ileal P digestibility, retention and tibia ash (P < 0.01) but effects were greater for Buttiauxella vs. E. coli phytase. In contrast, only Buttiauxella phytase increased the ileal digestibility of protein and total AA (+3.7% on average vs. NC at 1046 FTU/kg, P < 0.05). Linear increases in ileal digestibility of all individual AA were seen with increasing dose of Buttiauxella (P < 0.05 in all cases) and were greatest for cysteine (+ 7.9% vs. NC at 1046 FTU/kg), whereas only 2 individual AA showed linear increases in digestibility in response to increasing dose of the E. coli phytase (cysteine and proline, P < 0.05). Ileal digestibility of Na (%) was markedly increased (less negative) by phytase, especially for the Buttiauxella phytase which produced a 96% increase in ileal Na digestibility at 1046 FTU/kg vs. NC. Across treatments, ileal digestibility of AA and Na were positively correlated (P < 0.001). These results provide insight into the ‘extra-phosphoric’ effects in broilers fed corn-soybean meal-based diets and suggest that the Buttiauxella and E. coli phytase had markedly different degrees of ‘extra-phosphoric’ effects on AA digestibility per standard FTU. The data showed that the AA digestibility response to increasing phytase dose do not follow the same response curve as for digestible P, and that the response curves are specific for different phytases.

A mono-component microbial protease improves performance, net energy, and digestibility of amino acids and starch, and upregulates jejunal expression of genes responsible for peptide transport in broilers fed corn/wheat-based diets supplemented with xylanase and phytase

ABSTRACTA total of 90 male Ross 308 broiler chicks were used in a digestibility and performance bioassay to explore the effect of reduction in dietary protein and digestible amino acids and inclusion of an exogenous mono-component protease on amino acid digestibility, net energy, jejunal gene expression, and bird performance. Four dietary treatments were created by the supplementation, or not, of 2 control diets with a mono-component exogenous protease. The control diets were corn/wheat/soybean meal-based and were formulated to be either nutritionally adequate or reduced in protein and amino acids (around 3%). The 2 control diets were supplemented with xylanase and phytase (2000 FYT). Treatments were therefore arranged as a 2 × 2 factorial design. The reduction in diet nutrient density had no significant effect on various experimental outcomes (including bird performance, amino acid digestibility, and net energy [NE]) that were measured with the exception of a reduction in the expression of aminopeptidase N and glucose transporter 2. However, the addition of exogenous protease resulted in an increase in weight gain and a reduction in feed conversion ratio (around 4%; P < 0.05) and an increase in the digestibility of several amino acids (P < 0.05) and starch (P = 0.06). Protease addition also resulted in an increase in both apparent metabolizable energy (AME) (+73 kcal/kg; P < 0.05) and NE (+107 kcal/kg; P < 0.05). The addition of exogenous protease to the diet also increased the jejunal expression of genes responsible for peptide transport (PepT2; P < 0.01) and starch digestion (sucrase isomaltase; P = 0.06). These results confirm the efficacy of exogenous protease in broiler diets that contain both xylanase and phytase and suggest substantial beneficial effects that extend beyond protein and amino acid nutrition. The effect of exogenous protease on energy partitioning, starch digestibility and the efficiency of nitrogen cycling is an area for further study.

Effect of chitosan oligosaccharide (COS) and l-arginine supplementation on broiler performance

Usage of antibiotic growth promoter is eliminated for the poultry production starting from January 2018. This policy may affect animal performance and health status in tropical countries like Indonesia. A study of Chitosan Oligosaccharide (COS) and L-arginine supplementation was carried out to evaluate the growth performance of broiler. A total of 300 DOCs (day old chickens) broilers with an initial average body weight of 46 g, were randomly treated into 5 treatments with 6 replications (10 unsexed birds in each pen) for 35 days. Dietary treatments were (P0) basal diet (BD) without supplement, (P1)BD + Antibiotic growth promoter (Zinc Bacitracine 200 mg kg−1) of diet, (P2) BD + COS 100 mg kg−1 of diet, (P3 ) BD + L-arginine 1.9% of diet, (P4) BD + COS mg kg−1 + L-arginine 1.9% of diet. The results showed that treatments with COS and L-arginine significantly (P <0.05) increased feed intake, body weight, weight gain and reduce feed conversion ratio at starter period compared with fed P0. Furthermore, feed conversion ratio and mortality were significantly (P <0.05) decreases at all treatments and body weight and weight gain significantly (P <0.05) increased only at COS treatment compared with fed P0, at the overall experimental periods. In conclusion, dietary addition of COS 100 mg kg-1 is able to use as alternative for antibiotic growth promotor replacement without giving effect on broiler performance

Farm system distribution of gastrointestinal and haemoparasites of pigs within Makurdi metropolis

Parasitic diseases remain a major constraint to pig production, causing high morbidity and mortality rates, reduction in feed conversion ratio and weight gain, as well as compromising the reproductive performance of infected animals. The prevalence of parasites is considerably influenced by the type of husbandry system practiced. This study was carried out to determine the prevalence and comparison of gastrointestinal and haemoparasites of pigs reared within Makurdi metropolis under intensive and extensive management systems. A total of 209 blood and 209 faecal samples were collected from both intensive and extensively reared pigs of different breeds and analyzed. Thin blood smear technique was used for haemoparasites screening while simple flotation and sedimentation techniques were applied for faecal analysis, after which the data were subjected to descriptive and inferential statistics for prevalence determination. Five different gastrointestinal parasites, namely Strongyles, Trichuris suis , Taenia solium , Balantidium coli and Isospora species, and three haemoparasites, namely Babesia species, Anaplasma spp and Eperythrozoon suis were observed; with Strongyles and Babesia species seen as the most prevalent parasites in the study area. The gastrointestinal and haemoparasites prevalences were higher in extensively reared pigs (93.33% and 48% respectively) compared to 53.73% and 33.58% respectively in intensive system. The study has established the prevalence of certain gastrointestinal and haemoparasite species, and the effect of management system on the prevalence of these parasites within Makurdi metropolis. The extensive system of management has been seen to favour the prevalence of the parasites. Keywords: Gastrointestinal Parasites, Haemoparasites, Makurdi, Management system, Pigs, Prevalence