Feed Conversion Research Articles

Effects of dietary digestible lysine levels in breeding Japanese quails on productive and reproductive performance, egg quality, blood metabolites and immune responses.

The vegetable-based diet alone does not provide the lysine (Lys) needed to maximize poultry productive performance. This experiment aimed to evaluate the effects of dietary digestible Lys (dLys) level on productive and reproductive performance, egg quality, blood metabolites and immune responses in breeding Japanese quails (Coturnix japonica). The experiment was conducted in a completely randomized design with 6 treatments, 5 replicates and 15 (12 females and 3 meals) 10-week-old breeding Japanese quails each. A basal diet was formulated to meet nutritional requirements of breeding quails except dLys. The basal diet was supplemented with graded (+0.82g/kg) levels of l-Lys-HCl, corresponding to dietary dLys levels of 0.690%, 0.755%, 0.820%, 0.885%, 0.950% and 1.015%. The experiment lasted for 12 weeks, which was divided into 3-4-week periods. Significant differences were observed for egg production (EP), egg mass (EM) and feed efficiency (FE) in response to increasing dietary dLys concentration with quadratic trends. The highest traits were observed in the birds fed with a diet containing 0.885% dLys. However, feed intake, egg quality, reproductive performance, blood metabolites and immune responses against sheep red blood cell inoculation were not significantly affected by increasing dietary dLys concentrations. The dLys requirements during 11-14, 15-18, 19-22 and 11-22 (overall) weeks of age for optimal EP, EM and FE, based on the quadratic broken-line regression analysis, were estimated 272, 265, 250 and 266; 293, 285, 264 and 279; and 303, 294, 281 and 293mg/bird/day, respectively. The dLys requirements vary depending on the EP phase and the trait being optimized. The estimated dLys requirement for FE was higher than those for EP and EM. During the peak stage of the first laying cycle, the dietary dLys level of 0.932% and a daily intake of 303mg dLys/bird are sufficient for optimal performance.

Aflatoxin B1-associated oxidative stress along with toxicopathological and immunological alterations is efficiently counteracted by dietary supplementation of distillery yeast sludge in broilers.

Aflatoxin B1 (AFB1) is among the most potent genotoxic and carcinogenic mycotoxins and is a major source of distress for the growing poultry sector. On the other hand, distillery yeast sludge or distillery sludge (DS) is a byproduct of molasses-based industries. It is often treated as a waste despite containing abundant nutrients particularly protein, basic amino acids, and vitamins along with other macro and micronutrients. This study was designed to investigate the oxidative stress and immunological alterations induced by AFB1 and their amelioration by dietary supplementation with DS. For this purpose, 360 newly hatched broiler chicks were randomly divided into twelve groups (30 birds each) and fed different combinations of AFB1 (100, 200, or 600µg/kg) and DS (5 or 10g/kg) for 42days. The parameters under consideration were body weight, feed conversion ratio (FCR), relative organ weights, histopathological examination of different visceral organs, total antioxidant capacity, antibody response to intravenous injection of sheep red blood cells, in situ lymphoproliferative response to phytohemagglutinin-P, and phagocytic potential through a carbon clearance assay system. The results of this study established that DS supplementation ameliorated AFB1-associated oxidative stress and ameliorated toxicopathological and immunological anomalies in groups given AFB1 at 100µg/kg and 200µg/kg; however, little to no relief was observed in birds fed AFB1 at 600µg/kg. The determination of the actual ratio of the AFB1 to the DS for substantiating the ameliorating effects requires further investigation.

Can air nanobubbles improve the swim bladder inflation in developing European perch? A pilot study of advanced water treatment.

Swim bladder inflation (SBI) is a fundamental step in larval development for both physostome and physoclist fish species. Failure of the SBI triggers higher energy expenditures of the individual, which negatively affects swimming ability, growth rate, feeding efficiency, susceptibility to predation, and survival rate. In aquaculture, the SBI failure is caused by different factors including: (a) water contamination with oil increasing the surface water tension and preventing the larvae from gulping air bubbles for inflation, and (b) bacterial aerocystitis of the swim bladder caused by gulped organic debris. Hence, novel and effective water treatment technologies such as nanobubbles can be employed in aquaculture to reduce the risk of low SBI. In the present study, we compared conventional water treatment, i.e. surface spray combined with skimmers with air nanobubbles either alone or in combination, on the SBI of European perch larvae. In the control, no water treatment technology was employed. All treatments showed higher SBI efficiency compared to the control. The control group showed the lowest percentage of swim bladder-inflated individuals associated with low body weight (BW). The highest BW and SBI efficiency was recorded with the combination of surface skimmer, spray, and nanobubbles. The current study offers the first investigation of the nanobubbles' effect on SBI promotion in larvae of European perch and gives motivation for future optimizations.

Effect of stimbiotic on growth performance, nutrient digestibility, oocyst shedding, blood profiles, and intestinal microbiota in necrotic enteritis-challenged broiler

This experiment was conducted to investigate the effect of stimbiotic (STB) in broilers with necrotic enteritis (NE). A total of 180 one-day-old Arbor Acres (initial body weight of 34.81 ± 1.04 g) were used in this experiment for 32 days. All broilers were randomly allocated into six treatments, and each experimental group had 10 replicate cages with three broilers per cage. The experiment was conducted in a 2 × 3 factorial design consisting of two levels of challenge (challenge and non-challenge) and three levels of STB (0, 0.05, and 0.1%). The NE challenge significantly decreased (P < 0.05) growth performance, heterophil levels in blood, and intestinal lesion scores compared to the non-challenge group. Supplementation of 0.05% STB significantly decreased (P < 0.05) feed conversion ratio and the number of oocysts per gram of feces compared to the supplementation of 0 and 0.1% STB. At the genus level, the supplementation of 0.05% STB significantly decreased (P < 0.05) the abundance of Enterobacterales compared to the other groups on d 32. In conclusion, supplementation with 0.05% STB in a diet could positively regulate the fecal microflora and alleviate the decline in growth performance and nutrient digestibility caused by NE.

Utilization of liquid multi-microbe probiotics supplemented urea red palm sugar block as a potential improving balance of microorganisms in digestive tract for cattle economical production

Probiotics are live microbial feed supplements, providing beneficial effects on the host animal by improving balance of microorganisms in digestive tract. This study aims to examine the benefits of liquid multi-microbe probiotic supplementation on nutrient digestibility and economical production of beef cattle. The treatments were including ration control using fresh forage of King grass (Pennisetum purpureum) + 350 g of URPS-Block without liquid probiotic supplement (T0), fresh forage of King grass (Pennisetum purpureum) + 350 g of URPS-Block + liquid probiotic supplement of 2.0 cc/liter fresh water (T1), fresh forage of King grass (Pennisetum purpureum) + 350 g of URPS-Block + liquid probiotic supplement of 4.0 cc/liter fresh water (T2) and fresh forage of King grass (Pennisetum purpureum) + 350 g of URPS-Block + liquid probiotic supplement of 6.0 cc/liter fresh water (T3). Experimental design applied the Randomized Block Design involving 24 male cattle, divided into six groups of animal ages and four liquid multi-microbe probiotic doses. Parameters were feed dried matter consumption (DMC), average daily gain (ADG), feed conversion and income over feed costs (IOFC). The data were analyzed by variance analysis continued by Duncan test. Results showed that liquid multi-microbe probiotics supplementation of 2.0 to 6.0 cc/liter fresh water and URPS-Block of 350 g/day added into forages increased significantly (P&lt;0.05) production of cattle indicated by significant higher ADG of 510 to 570 g (P&lt;0.05) compared with those of control ration producing ADG of 380 g. The increase of animal production was supported linearly by the increasing drinking water consumption supplemented with liquid probiotic levels of 2.0 to 6.0 cc/liter fresh water of animals. Cattle supplemented with liquid probiotic of 2.0 to 6.0 cc/liter fresh water/animal/day also produced higher IOFC, equivalent with increases of 55.67 to 80.87 percents IOFC compared with the animals fed the control ration without liquid probiotics.

Growth performance, serum metabolites, plasma protein fraction, meat lipid profile and antioxidant activities of breast meat of broiler chicken fed diets containing Cinnamomum ceylon powder, Zingiber officinale powder and Moringa oleifera leafmeal supplem

An experiment was conducted to determine growth performance, serum metabolites, plasma protein fraction, meat lipid profile and antioxidant activities of meat of broilers as affected by Cinnamomium ceylon, Zingiber officinale and Moringa oleifera supplementation. A total of 112 day old chicks were allotted into four treatments replicated four times with seven birds per replicate in a completely randomized design (CRD). Basal diets were formulated for broiler starters (0-28days) and finisher phase (29-56) days. The basal diets were divided into 4 diets : diet 1- control diet without supplementation; diet 2- contained 0.2% Cinnamomum ceylon supplementation (CCS); diet 3- contained 0.2% Zingiber officinale supplementation (ZOS), diet 4-contained 0.2% Moringa oleifera leafmeal (MOLM) supplementation. The experiment lasted for 56 days. Results showed an improvement in final liveweight, weight gain, feed intake and feed conversion ratio of birds on 0.2% MOLM. Birds on phytogenic feed additives have lower values of urea, cholesterol, glucose, high density lipoprotein and low density lipoprotein. Birds administered phytogenic supplements exhibited much greater plasma albumin levels. Low levels of meat cholesterol, triglycerides and low density lipoprotein were found in birds fed phytogenic feed additives while high levels of high density lipoprotein were recorded for birds on phytogenic feed additives. The supplementation of broilers diets with phytogenic feed additives increased the glutathione peroxidase and superoxide dismutase and decreased lipid peroxidation. It was concluded that supplementation of broiler diets with Moringa oleifera leaf meal enhanced body weight gain, antioxidant activities also reduced cholesterol level in both serum metabolites and meat.

Comparative growth, production, carcass characteristics and reproduction performance of Naked Neck, Black Australorp and their crossbred chicken

This study evaluated the phenotypic and genetic parameters of indigenous Naked Neck (NN), exotic Black Australorp (BA), and their crossbred (NNBA) chickens. A total of 270 day-old chicks (30 per group) were raised under identical conditions from day 1 to 48 weeks of age. Growth performance, including body weight, daily and total gain, feed consumption, and feed conversion ratio (FCR), was highest in BA, followed by NNBA, and lowest in NN. Carcass composition also varied significantly, with BA and NNBA having higher dressing percentages (62.98% and 62.68%, respectively) compared to NN (60.60%). BA produced the heaviest eggs (54.0 g), followed by NNBA (50.9 g) and NN (47.93 g). BA also had the best egg quality, hatchability, and FCR (3.15), with NNBA showing intermediate results. NN had the poorest performance in all traits. Age at sexual maturity was earlier in NNBA (161.23 days) compared to NN and BA. The study concluded that NNBA crossbreds outperformed NN in growth, carcass traits, and egg production, indicating their potential for enhancing rural poultry farming.

Effects of three different strains of Bacillus-based probiotics and Saccharomyces cerevisiae-based prebiotic on performance, egg components and gene expression of laying hens during phase II of production

This study aimed to investigate the impacts of three strains of probiotics (Bacillus spp. (B.)) and one prebiotic based on Saccharomyces cerevisiae cell wall (SCCW) supplements on performance, egg quality and immune-related gene expression of laying hens. The experiment lasted 16 weeks (52–68 weeks), during which 450 Hisex white layers at 52 weeks were randomly allocated into five dietary regimens (five replications of 18 birds per floor pen): T1, basal diet; T2, basal + 0.5 g/kg B. subtilis (DSM17299); T3, basal + 0.5 g/kg B. subtilis (DSM 5750) and B. licheniformis (DSM 5749); T4, basal + 0.4 g/kg B. subtilis PB6; and T5, basal + 0.25 g/kg SCCW. The results showed that hen-day egg production (HDEP) improved in T4 and T5, egg mass (EM) improved in T3, T4 and T5, and feed conversion ratio (FCR) improved in T4 and T5 compared to T1 (p < .001). Relative wet and dry yolk weight were higher in hens received T2, T4 and T5 (p < .05) and T2, T3, T4 and T5 (p < .001), respectively, compared to T1. Moreover, T2, T4 and T5 had higher expression of GnRH-2 gene compared to T1 (p < .01). In conclusion, the dietary inclusion of SCCW-based prebiotic (T5) and Bacillus spp. probiotic strains, especially T4 B. subtilis PB6 improved production performance, egg components and GnRH-II gene expression of laying hens during phase II of the production cycle and hold a great promise for boosting productivity and supporting health status of layers raised on AGPs-free diets.

Mediterranean Aquaponics: Fasting and Refeeding in a Polyculture Aquaponic System

The use of Mediterranean euryhaline fish and halophytes in aquaponics presents a sustainable and alternative approach to food production. The present study investigates the effect of compensatory growth on sea bass (Dicentrarchus labrax) and Baltic prawn (Palaemon adspersus) co-cultivated with the halophytic glasswort (Salicornia europaea). Three autonomous systems were established, each containing forty-five sea bass, nine Baltic prawns, and eight glasswort plants, with different feeding regimes for each treatment: (i) daily feeding (treatment A), (ii) three days of feeding per week followed by four days of fasting (treatment B), and (iii) feeding for seven days followed by seven days of fasting (treatment C). The growth performance of the fish was significantly higher in treatment B. Conversely, the feed conversion ratio (FCR) was notably higher in treatment A. As for the prawns, their final body weight and length were similar across all treatments. The glasswort plants also demonstrated significantly improved growth in treatment B. These results indicate that the incorporation of feeding and fasting cycles can be an effective feed management strategy for polyculture aquaponic systems. Additionally, food deprivation had a positive impact on the growth performance of both glasswort and prawns.

Does the Use of the Yeast Probiotic Saccharomyces cerevisiae Actisaf Sc 47 Reduce the Environmental Impacts of Beef Cattle? A Study Based on Life Cycle Assessment

Increasing animal protein, especially from beef, is necessary to satisfy the requirements of the growing global population. However, this is becoming increasingly challenging due to stakeholders prioritizing sustainable systems with low environmental impacts. To answer these challenges, the use of feed additives such as yeast probiotics seems to be an effective route for improvements in feed efficiency and growth performance. The current study was performed to quantify the environmental impacts of the production and use of a yeast probiotic (Actisaf® Sc 47) through an LCA method in four trials performed during the fattening period: France (French trial), Spain (Spanish trial), and Italy (Italian trials A and B). During each trial, two groups of animals with the same characteristics were compared during the fattening period: the control group without Actisaf® Sc 47 supplementation used as a baseline, and the experimental group with Actisaf® Sc 47 supplementation. The calves started the trial at the ages of 224, 92, and 186 days during the French, Spanish, and Italian trials A and B, respectively. Of the sixteen impact category indicators, nine were analyzed. In Italian trials A and B, the Spanish trial, and the French trial, the use of Actisaf® Sc 47 reduced CC by 4.8, 3.8, 6.6, and 5.4%; FE by 4.8, 3.9, 8.2, and 6.3%; ME by 4.9, 4.0, 6, and 6.4%; and TE by 5.3, 4.1, and 6.2%, respectively. Moreover, during the same trials, Actisaf® Sc 47 reduced AC by 6.0, 4.1, 6.3, and 7.1%; LU by 4.7, 3.9, 5.8, and 6.1%; WU by 4.5, 3.4, 5.2, and 5.9%; RU (fossils) by 4.8, 3.7, 7.3, and 4.8%; and PM by 5.2, 4.1, 6.3, and 7.1%, respectively. The use of Actisaf® Sc 47 has beneficial effects on the environment. Regarding Actisaf® Sc 47 production, the results showed that the production of 1 kg of Actisaf® Sc 47 emitted 2.1 kg of CO2 eq, 60% of which came from the fermentation process and 39% from drying. The results demonstrate the interest in using Actisaf® Sc during the fattening period for its multiple positive outcomes: improving performance and efficiency, while reducing the global carbon footprint.

The Effects of Corncob and Xylanase Supplementation on Performance, Ileal Digestibility, Intestinal Morphology, Gastrointestinal pH and Serum Biochemical Traits in the Broiler Chickens

This study evaluated the effects of corncob as a source of insoluble fibre and xylanase enzyme on broiler chicken performance, ileal digestibility, intestinal morphology, gastrointestinal pH, and serum biochemical traits. 256-one-day-old (Ross 308) broiler chicks were randomly given six diets for 24 days: a control diet with 0%, 2.5%, or 5% corncob, with or without xylanase, in a 3 × 2 factorial arrangement. Then, chicks were given the control diet with or without xylanase until they reached 42 days. Adding corncob to diets reduced performance during the grower phase (P≤0.05), but when removed, the performance did not differ from the control (P≥0.05). Corncob reduced ash digestibility and cholesterol levels (P≤0.05) while increasing the relative weight of the heart, gizzard, and duodenum and improving the ileal villus high-to-crypt depth ratio (P≤0.05). The feed conversion ratio increased due to corncob inclusion in diets at the starter and grower phases (P≤0.05) but did not differ from the control at the finisher phase. Xylanase supplementation improved performance, nutrient digestibility, intestinal histomorphology, and reduced cecum weight with digestive tract pH (P≤0.05). Therefore, adding corncob with xylanase enzyme to broiler chickens' diet does not negatively impact their performance. On the contrary, it improves the broilers' health and reduces production costs.

Trans-10 shifted ruminal biohydrogenation and its implications for ruminant milk and meat fat content and quality

Feeding high-grain diets is a common practice in intensive ruminant production systems to meet animal energy requirements and maximize feed efficiency. One of the consequences of these diets is trans (t)10 shifted ruminal biohydrogenation, which includes increased formation of t10-18:1 and t10,cis (c)12-conjugated linoleic acid (t10,c12-CLA) at the expense of t11-18:1 and c9,t11-CLA. In dairy cows, the t10 shift has been associated with milk fat depression. In beef cattle, the t10 shift has not been associated with negative effects on animal performance or marbling fat deposition, however, it may negatively impact meat fat eating quality by decreasing its cis monounsaturated fatty acid to saturated fatty acid ratio. Finally, the t10 shift increases t10-18:1 accumulation in ruminant-derived foods (dairy, beef and lamb) which at high enough levels may compromise the nutritional quality of these foods. The present review will cover our current understanding of the rumen microbes involved in the t10 shift and its implications for milk fat synthesis and beef fat quality.

EFFECT OF ADDING NATURAL AND NANO ZINC OXIDE TO THE DITE ON SOME GROWTH PARAMETERS OF CYPRINUS CARPIO L .

The research aimed to study the effect of natural and nano zinc oxide on some growth parameters of common carp Cyprinus carpio. Seven treatments were used, including the control without any addition, the second, third and fourth treatments by adding nano-zinc oxide at concentrations of 25, 50 and 75 mg/kg feed, respectively, and the fifth, sixth and seventh treatments by adding natural zinc oxide in the same concentrations above. The results showed that the fourth treatment was superior to the traits of the total weight gain, daily growth rate, relative and specific growth rate over the other treatments, which is an indication that the fish benefit from feed enhanced with nanoparticles by 75%, and it differed significantly )p (0.01&gt;from the rest of the treatments. T4 treatment was recorded the best daily growth was 0.29 g/day The best feed conversion ratio was recorded in the same treatment. It can be concluded from the study that the addition of zinc nanoparticles to the diet of fish improves the level of performance and growth without causing any harm to the fish.

Effects of Dietary Inclusion of Enzymatically Hydrolyzed Compound Soy Protein on the Growth Performance and Intestinal Health of Juvenile American Eels (Anguilla rostrata)

The enzymatic hydrolysis of soybeans could enhance their application as an ingredient and alternative to fishmeal in aquafeeds. Here, a 10-week feeding trial was conducted to evaluate the impacts of different dietary inclusion levels of enzymatically hydrolyzed compound soy protein (EHCS) on the growth performance and intestinal health of juvenile American eels (Anguilla rostrata). Five experimental diets were formulated with graded EHCS inclusion levels at 0% (EHCS0), 8% (EHCS8), 16% (EHCS16), 24% (EHCS24), and 32% (EHCS32). Each diet was randomly assigned to four replicate tanks. The results showed that eels fed the EHCS8 diet exhibited superior growth performance, decreased serum lipid content, and increased immunity compared to those fed the EHCS0 diet. Eels fed the EHCS8 diet also displayed improved intestinal histology, enhanced antioxidant capacity and balance of intestinal microbiota as well as an enhanced proliferation of probiotics compared to those receiving the EHCS0 diet. Compared with eels fed the EHCS0 diet, those fed the EHCS16 diet exhibited comparable growth performance and values for the aforementioned markers. The quadratic regression analysis of weight gain rate and feed efficiency against the dietary EHCS inclusion levels determined the maximum levels of dietary EHCS inclusion for American eels range from 17.59% to 17.77%.

Effect of copepod Apocyclops dengizicus addition on growth, survival, and proximate composition of Macrobrachium rosenbergii postlarvae cultured in brackish‐water biofloc system

AbstractObjectiveThe effects of periodically adding the cyclopoid copepod Apocyclops dengizicus (every 4 days at a rate of 4 individuals/mL) with biofloc technology (BFT‐C) was compared with conventional biofloc technology (BFT; without copepod) or a clear‐water control for Macrobrachium rosenbergii postlarvae nursery culture.MethodsSurvival, growth, proximate composition, and economics of SMacrobrachium rosenbergii postlarvae was calculated. Water quality and biofloc proximate composition were also measured among treatments. For the BFT, maize starch was applied to achieve a C:N ratio of 20:1. Triplicate 125‐L polyethylene tanks containing 500 postlarvae each (9.40 ± 1.88 mg) were evaluated.ResultSpecific growth rate was significantly greater in the BFT‐C group (8.40 ± 0.24% per day) than BFT (7.23 ± 0.21% per day) and control (7.12 ± 0.42% per day) groups. Postlarvae survival was significantly increased with the BFT‐C (94.46%) treatment compared with the BFT (87.33%) and control (82.60%). A significantly lower food conversion ratio (1.08) was obtained in BFT‐C than both the BFT (1.73) and control (1.90), possibly due to significantly higher biofloc crude protein and lipid contents in the BFT‐C than BFT. Postlarvae whole‐body protein and lipid contents were significantly elevated in BFT‐C compared to the BFT and control treatments. Economics of gross return, net return, and cost‐benefit ratio were significantly better at BFT‐C than in either the BFT or control groups.ConclusionThis study indicates that copepod additions with BFT enhanced prawn postlarvae survival, growth, and whole body protein and lipid, as well as economics, which could augment productivity and sustainability in this industry.

Supplementation of Chlorogenic Acid Alleviates the Effects of H2O2-Induced Oxidative Stress on Laying Performance, Egg Quality, Antioxidant Capacity, Hepatic Inflammation, Mitochondrial Dysfunction, and Lipid Accumulation in Laying Hens

This research examined the impact of chlorogenic acid (CGA) on laying performance, antioxidant capacity, egg quality, hepatic inflammation, mitochondrial function, and lipid metabolism in hens subjected to hydrogen peroxide (H2O2)-induced oxidative stress (OS). Three hundred sixty healthy 43-wk-old Hy-Line brown hens were randomly assigned to six treatments: a basal diet + 0 (control and H2O2), 600 (600 mg/kg CGA and 600 mg/kg CGA + H2O2), and 800 (800 mg/kg CGA and 800 mg/kg CGA + H2O2) mg/kg CGA for 84 d. On the 64th and 78th days of the trial, hens in groups H2O2, 600 mg/kg CGA + H2O2, and 800 mg/kg CGA + H2O2 were injected intraperitoneally with 10% H2O2. The results demonstrated that 600 and 800 mg/kg CGA significantly improved the egg production rate (EPR) and egg quality and reduced lipid peroxidation compared to the control group. The 800 mg/kg CGA showed greater improvements in the EPR and average egg weight (AEW) compared to the 600 mg/kg dose. Conversely, H2O2 exposure significantly decreased the EPR, AEW, and egg quality and increased feed conversion rate and average daily feed intake. H2O2 exposure significantly decreased serum T-AOC and increased serum MDA levels while reducing hepatic T-SOD, GSH-Px, and CAT activities. Meanwhile, H2O2 exposure significantly elevated liver reactive oxygen species levels, pathological damage, and NF-κB, TNFα, and IL-1β gene expression. Additionally, H2O2 treatment disrupted hepatocyte mitochondrial structure and significantly increased the expression of VDAC1 protein, and IP3R, GRP75, MCU, Fis1, and MFF genes, while downregulating the expression of MFN2 protein and PGC1α gene. Oil Red O staining demonstrated that H2O2 induced significant lipid accumulation in hepatocytes. Concurrently, H2O2 significantly increased serum triglycerides, total cholesterol, and liver triglycerides levels while decreasing serum hepatic lipase activity. This was primarily attributed to the significant upregulation of liver SREBP1, FASN, and ACC genes and the downregulation of the liver CPT1 gene induced by H2O2. Furthermore, CGA pretreatment effectively prevented the degeneration in laying performance and egg quality, as well as OS, liver inflammation, pathological damage, and mitochondrial dysfunction induced by H2O2. CGA inhibited H2O2-induced hepatic lipid accumulation by upregulating fatty acid oxidation-related gene expression and downregulating fatty acid synthesis-related gene expression. These findings indicate that the dietary addition of 800 mg/kg of CGA is the optimum supplementation dose. CGA can enhance laying performance and egg quality while alleviating OS, hepatic inflammation, mitochondrial dysfunction, and lipid accumulation in H2O2-challenged laying hens.

Evaluation of protease plus a precision-biotic on body weight gain and feed conversion ratio in broilers from 0 to 42 days of age

This study aims to evaluate the effects of a protease combination with a precision biotic on body weight gain (BWG) and feed conversion ratio (FCR) of broilers from day 0 to 42. 1,400 Cobb 500 male chicks were reared on seven different diets, including an unrestricted positive control (PC–Diet 1) and a negative control (NC–Diet 2) with slightly reduced crude protein, apparent metabolizable energy (AME), and digestible amino acids. Five additional treatment diets were formulated using the negative control and varying concentrations of a protease (Diets 3-4; 33ppm and 50ppm, respectively) and in combination with a precision biotic (Diets 5-7; 33ppm + 700ppm; 50ppm + 500ppm; and 50ppm + 700ppm, respectively). The PC treatment showed significantly different feed intake and FCR compared to all other treatments in all production phases (P &lt; 0.05). There are no significant differences in non-PC treatments in all production phases for BWG and FCR (starter p=0.230 and 0.300; grower p=0.443 and 0.237; finisher p=0.450 and 0.896; overall p=0.111 and 0.497, respectively), nor is there any in terms of mortality (p=0.800). These findings may provide valuable information to producers to optimize flock performance efficiently and cost-effectively.

The impact of myostatin variants on growth traits in South African Bonsmara beef cattle

Double muscling occurs when the myostatin (MSTN) gene is deactivated due to a series of mutations, leading to uncontrolled muscle growth and excessive muscle fiber accumulation, as the gene can no longer effectively regulate muscle development. This study aimed to assess the impact of MSTN variants and their combinations on growth traits, namely direct birth weight (BWDIR), direct weaning weight (WWDIR), average daily gain (ADG) and feed conversion ratio (FCR) in the South African (SA) Bonsmara. Genomically enhanced estimated breeding value (GEBVs) for traits of interest, and MTSN genotypes for SA Bonsmara animals were available for the study. Thirteen MSTN variants (Nt821, Q204X, F94L, E226X, E291X, C313Y, Nt419, S105C, D182N, Nt414, Nt324, Nt267, and Nt748) were routinely genotyped using the IDBv3 SNP array. Genotypic frequencies of MSTN variants ranged from 1.18% for Q204X to 35.02% for Nt748. No association was observed between the Nt267 variant and any growth traits, while both Nt748 and Nt414 variants affected WWDIR, ADG and FCR (p < 0.05). The results of the effect of multiple variants on growth traits indicated that there was an additive effect when more than one MSTN variant was present in an individual. This study is the first study to report the impact of MSTN variants on traits of economic importance in the SA Bonsmara breed.

The efficacy of prebiotic supplementation in mitigating heat stress and improving the survival of antibiotic-free broilers’ production in hot climates

BackgroundBangladesh is a hot tropical country, and various antibiotics have been included in broiler feed for many years to manage, prevent, and treat illnesses and improve production performance, like many other developing countries. This study mainly evaluates the efficacy of prebiotic supplementation in mitigating heat stress and improving the survival of antibiotic-free broiler production in hot climates.Materials and methodsA cocktail of banana peel, papaya peel, and watermelon rind was used as a prebiotic. A total of 350 one-day-old chicks (Ross-308) were allotted into five treatment groups each with 7 replicates: T1 (prebiotics, 15 ml/L), T2 (commercial probiotics Lactolase P, 1 g/L), T3 (synbiotics, 7.5 ml/L prebiotics + 0.5 g/L probiotics), T4 (freshwater), and T5 (antibiotics, 1 g/L). Besides other treatments, the aqueous extracts of banana peels, papaya peels, and watermelon rinds were prepared as prebiotics, and these were provided to the experimental birds through drinking water from 5 to 32 days of age.ResultsThe findings revealed nonsignificant (P > 0.05) variations in water intake, feed intake, feed conversion ratio (FCR), dressing weight, dressing percentage, heart and gizzard weights, and thigh meat yield. Significant (p < 0.05) differences were observed in body weight, body weight gain, and breast meat yield. It was observed that birds consumed five times more water than feed when the environmental temperature was above 38 °C. Significant (p < 0.05) differences in the survival rates of birds were observed among treatment groups. The highest rate of survival was obtained in T1 (100%), followed by T2 (93.3%), and T3 (90%), and the lowest percentage was recorded in T4 (66.6%) and T5 (73.3%).ConclusionPrepared prebiotics could mitigate heat stress, promote growth rate under hot climates, and be used as substitutes for antibiotics to safely produce broilers in hot climates.

Effect of coated calcium feeding on growth performance, carcass traits, immunity, blood biochemistry and tibial bone morphometry in commercial broiler chicken.

The bone abnormalities pose great concern in heavy, rapidly growing broilers, resulting in significant economic loss, and health issues in birds. To address these problems and prevent unnecessary mineral excretion into environment, it is crucial to optimise the inclusion level of dietary calcium in broiler's diet. The calcium utilisation by the bird is also affected by its source, particle size, bioavailability etc. Hence this study aimed to study the effect of partially replacing conventional dietary calcium source with coated calcium on growth performance, immune response, carcass traits, blood calcium and phosphorus, and mineral retention in broilers. About 416 broiler chicks were randomly distributed into four treatments, each with eight replicates of 13 birds and fed with iso-calcium, isocaloric, and isonitrogenous diet for 42 days. The T0 (control) was a basal diet while the T1, T2, and T3, were treatment diets in which conventional calcium source (limestone) was partially replaced with coated calcium by 10, 20, and 30% respectively. The birds of T3 group showed higher (P < 0.05) body weight gain, better feed conversion ratio and higher carcass yields compared to T0, T1, and T2 diet fed birds. Further the treatment groups exhibited higher (P < 0.05) cell-mediated and humoral immune responses and immune organ weights compared to control. The tibial bone weight, length and average diameter was highest (P < 0.05) in T3. Moreover, the T3 diet fed group also showed higher (P < 0.05) calcium and phosphorus content in serum and bone and lowest content of these minerals in the excreta followed by T2, T1 and control. These findings suggest that a 30% conventional calcium source with coated calcium may be used as a high-grade mineral source for broiler chicken feed.