Feed Conversion Research Articles

Withania coagulans root powder effect on growth, hematology, digestive enzyme activity, antioxidant status, serum immune response, and tolerance against Aeromonas hydrophila in Common Carp

AbstractObjectiveThe use of plant‐derived products in aquaculture has garnered considerable attention due to their potential benefits. This study investigated the impact of supplementing Withania coagulans root powder (WCRP) in the diet of Common Carp Cyprinus carpio on various parameters, including growth performance, digestive enzymes, hematology, antioxidant activity, and immunological aspects.MethodsCommon Carp (mean weight ± standard deviation = 11.69 ± 0.48 g) were divided into four groups in triplicate, receiving different WCRP concentrations (0.0, 1.0, 1.5, and 2.0%; labeled as WCRP0, WCRP1.0, WCRP1.5, and WCRP2.0, respectively) over a 60‐day period, followed by an experimental challenge with Aeromonas hydrophila to assess the relative percentage survival (RPS) over 14 days.ResultResults showed that Common Carp receiving WCRP1.5 and WCRP2.0 demonstrated significantly improved growth performance, with reduced feed conversion ratios (FCRs) being particularly evident in WCRP1.5. Polynomial contrasts indicated significant linear and quadratic effects on weight gain and FCR. Additionally, WCRP1.5 and WCRP2.0 supplementation led to significantly higher activity of digestive enzymes (lipase and protease). Hematological parameters, including white blood cells, red blood cells, hemoglobin, and hematocrit, were significantly elevated in fish that were fed WCRP1.5 and WCRP2.0 compared to the control group. Moreover, serum parameters, such as total protein, albumin, globulin, lysozyme, catalase, superoxide dismutase, and total immunoglobulins, were significantly enhanced in WCRP1.5‐ and WCRP2.0‐treated fish. Notably, the WCRP1.5 group showed the lowest serum cortisol levels. The RPS was highest in WCRP1.5 (73.77%), followed by WCRP2.0 (70.43%), compared to the other groups.ConclusionIn conclusion, supplementation with WCRP1.5 and WCRP2.0 effectively improved both growth and health parameters in Common Carp.

Coated oregano essential oil and cinnamaldehyde compounds supplementation improves growth performance, enhances immune responses and inhibits cecal Escherichia coli proliferation of broilers.

Plant essential oils are unstable due to high volatility and easy oxidation, while microencapsulation provides a potentially effective strategy for increasing the stability of natural essential oils and preserving their function. This study examined the effects of feeding coated oregano essential oil and cinnamaldehyde (COEC) compounds on growth, immune organ development, intestinal morphology, mucosal immune function, and the cecal microbiota populations of broilers. Three hundred one-day-old male Arbor Acres broiler chicks were organized into five groups: (1) negative control fed basal diet alone (NC), (2) positive control receiving basal diet plus 50mg/kg of chlortetracycline (CTC), (3) basal diet plus 150mg/kg COEC (COEC150), (4) plus 300mg/kg COEC (COEC300), and (5) plus 450mg/kg COEC (COEC450). The supplement trial was continued for 42 days. The results showed that CTC, COEC300 and COEC450 treatments decreased the feed conversion ratio of broilers both in the starter and whole experiment phases, increased the height of jejunal villi at 21 d and the number of goblet cells and IgA-producing cells at 21 or 42 d compared with NC group (P < 0.05). Members of the COEC300 treatment group had a higher thymus weight index and jejunum length index than birds of NC or CTC groups at 21 d (P < 0.05). CTC and all COEC treatments decreased malondialdehyde content in jejunal mucosa at 42 d (P < 0.05). The population of Escherichia coli in the cecal digesta at 21 d was lower in the CTC, COEC300 and COEC450 treatment groups compared with the NC group (P < 0.05). In contrast to the CTC group, COEC supplementation dose-dependently accelerated body weight gain, improved jejunal morphology, decreased malondialdehyde content in jejunal mucosa, increased numbers of jejunal goblet cells and IgA-producing cells, and decreased the Escherichia coli population in cecal digesta at 21 or 42 d (P < 0.05). Thus, we concluded that feeding broiler chickens with 300 or 450mg/kg in antibiotic-free diets can improve growth performance, enhance immune responses and inhibit the proliferation of cecal pathogenic bacteria.

Effect of a Bacillus subtilis-based direct-fed microbial, on milk yield, milk components, feed intake and plasma hormones and metabolites in lactating Holstein cows

To investigate the effects of a Bacillus-based direct-fed microbial on milk production and related factors, a study was conducted on Holstein cows (n = 28) starting at 90 ± 11 DIM. The cows were divided into two dietary groups: a control group (CON) that received a total mixed ration (TMR), and a Bacillus-fed group (DFM) that received the same TMR along with a Bacillus subtilis product containing two strains (747 and 1781) in equal amounts. The study lasted for 25 wk and included both primiparous and multiparous cows. The cows were housed in a free-stall barn and were provided with ad libitum TMR, which was fed twice a day. Their daily meals and dry matter intake (DMI) were recorded during wk 1–4 and wk 19–25 using electronic feeders. Milk samples were collected weekly during morning and evening milkings and analyzed for milk fat, protein, lactose, and milk urea nitrogen (MUN). Blood samples were also collected weekly and analyzed for plasma glucose, insulin, cholesterol, insulin-like growth factor 1 (IGF1), and progesterone concentrations. Additionally, rumen fluid samples were collected and evaluated for various species of bacteria. One of the key findings was that daily 4 % fat-corrected milk production (FCM) was influenced by the interaction between treatment (DFM vs. CON) and parity (primiparous vs. multiparous), with multiparous DFM cows producing 11 % more FCM compared to CON. The DFM cows also had a higher milk fat percentage (4.41 % vs. 4.02 %) and MUN concentrations were 1.0 mg/dL higher in the DFM group. In terms of blood metabolites and hormones, multiparous DFM cows had lower plasma cholesterol, glucose, and insulin concentrations compared to CON multiparous cows. However, there were no significant differences between the groups in terms of plasma IGF1 concentrations, insulin-to-glucose ratios, and luteal phase plasma progesterone concentrations. The analysis of rumen fluid samples revealed that the abundance of Ruminococcus albus and Fibrobacter succinogenes group I was greater in the DFM cows compared to CON cows. Furthermore, during the periods when feed intake was measured, the DFM cows had a 9 % reduction in feed intake and a 14 % improvement in feed efficiency (FCM per DMI) compared to CON cows. In conclusion, the two-strain Bacillus product used in this study (Certillus) showed potential as an effective direct-fed microbial. It was found to increase feed efficiency and milk production by altering the composition of ruminal microbiota and metabolism in the cows.

Effect of grinding method and extent of pelleting of broiler diets on performance, feeding behaviour and digestive tract functionality

ABSTRACT 1. An experiment was carried out to examine if a heterogeneous diet consisting of pellets and coarse cereal particles would result in a similar feed intake to pelleted-only diets. It also considered whether coarser particles entering the gizzard would encourage the development of the gizzard and thus improve digestive tract functionality. Maize and wheat were hammer milled through a 3 mm screen after coarse grinding using either one of the two screens with a novel pattern. Three pellet-only diets were produced based on three grinding sizes. Additionally, four diets were produced by separating coarse cereal particles from moderately coarse particles by sieving either once or twice, pelleting the remainder and finally mixing these into a complete heterogeneous diet. 2. No difference in performance between birds fed the three pelleted-only diets was observed. However, heterogeneous diets resulted in a lower feed intake (FI) and weight gain (WG) than pelleted-only diets (p < 0.05). The dietary treatments neither affected the feed conversion ratio nor ileal digestibility of starch and protein (p > 0.05). As expected, feeding a heterogeneous diets increased (p < 0.05) the relative weight of the gizzard and its contents. Approximately 50% of the particles in the small intestine were between 0.15 mm and 0.36 mm in diameter, with more fine particles observed when the pelleted-only diets containing coarsely ground cereals were fed, confirming the capacity of the gizzard to finely grind feed. 3. Sieving of the diet remaining in the feeder during 4 h of feeding two of the heterogeneous diets showed that the particles > 2.8 mm disappeared first (p < 0.05), showing the birds’ preference for larger particles when offered heterogeneous diets. Although the birds were able to handle the coarse microstructure of the diets without any negative effects, the reduced performance in the case of heterogeneous diets might have been related to feed intake issues and particle selection, resulting in an imbalance in nutrient intake.

Effects of fermented Chinese herbal medicine feed additives on growth performance and intestinal microbiota of piglets.

Fermented Chinese medicine (FCM), as a functional feed additive, has been widely recognized to play a significant role in protecting the intestinal health of piglets and enhancing productive performance. However, the relationship between the active components of FCM, gut microbiota, and their beneficial effects on animal performance remains unclear. In this study, metabolomics analysis revealed a significant increase in the main contents of lactic acid and propionic acid in FCM, while most glycosides and their derivatives decreased after three days of microbial fermentation. Subsequently, piglets were fed a basic diet supplemented with 1% FCM, while the control group received only the basic diet. The results indicated a significant increase in feed intake and average daily gain within 14 days (P<0.05) due to FCM supplementation. Additionally, FCM significantly improved feed efficiency from 1.76 to 1.50 (P<0.05), and piglets in the FCM group exhibited significantly lower frequencies of diarrhea and coughing, which indicated improved health condition by FCM. Moreover, high-throughput sequencing analysis revealed higher abundances of Lactobacillus agilis, Megasphaera elsdenii, Ligilactobacillus, and Veillonellaceae in FCM group. In summary, FCM increased the content of active metabolites through microbial fermentation and regulated the intestinal microbiota to improve the health of piglets. FCM offers a promising potential for enhancing production performance and economic efficiency in the livestock industry.

Implication of dietary barberry (Berberis Vulgaris) leaves inclusion on growth performance, nutrient digestibility, and carcass traits in ostriches

This study determined production performance, nutrient intake, digestibility, and carcass traits from ostrich chicks fed with barberry (Berberis Vulgaris) leaves (BVL) as a replacement for alfalfa hay (AH). For 150 days, 30 male ostrich (Struthio camelus) (9.10 ± 0.89 kg live weight, mean ± SD) were randomly grouped into five dietary BVL inclusion levels to replace AH: a control diet based on 100% AH (CTRL), and four groups with BVL as a substitute for AH at varying levels including 25% (BVL25), 50% (BVL50), 75% (BVL75), and 100% (BVL100). The average daily feed intakes (ADFI) were recorded and birds were weighed monthly. The nutrient intake and digestibility were measured for the following final 5 days of the trial. The ADFI was higher (p = 0.025) for BVL100 and BVL75 than for CTRL. Ostriches fed on BVL50 had the highest average daily gain (ADG, p = 0.025) and the lowest feed conversation ratio (FCR, p = 0.0001). Return per kg BW gain was also enhanced (p = 0.018) with BVL50 feeding. Dietary BVL levels did not affect the digestibility of OM (p = 0.257), CP (p = 0.260), EE (p = 0.610), CF (p = 0.427), and Ash (p = 0.461). Also, there were no changes in AME (p = 0.180) or AMEn (p = 0.670). The hot carcass weight (HCW, p = 0.331) and dressing BW (p = 0.237) were not affected. Overall, the results suggest that BVL can replace AH in ostrich diets without deleterious impact on performance, however, its partial substitution (for 50% AH of diet) has been associated with improved ADG, FCR, and reduced feeding costs.

An emerging role of ferulic acid on sub-adult grass carp (Ctenopharyngodon idellus): Increasing protein digestion and regulating amino acid and oligopeptide transporters expression

This study was conducted to evaluate the effect of supplement ferulic acid on growth performance, digestive ability and transport function of amino acids and oligopeptides in the intestine of sub-adult grass carp (Ctenopharyngodon idellus). The experiment was divided into two parts: a. Digestion experiment: healthy grass carp (678.83±1.00 g) were divided into two groups: control group (0 mg/kg FA) and ferulic acid group (100 mg/kg FA) for 2 weeks; b. Growth experiment: healthy grass carp (678.83±1.00 g) were divided into five treatment groups, the control group (FA0) with no ferulic acid and the experimental group supplemented with ferulic acid 50 (FA50), 100 (FA100), 150 (FA150) and 200 (FA200) mg/kg feed for 9 weeks. The results showed that a. Ferulic acid supplementation increased the apparent digestibility of crude protein and crude fat in grass carp. b. Ferulic acid supplementation improved the growth performance and feed efficiency (FE) of grass carp; increased the activities of trypsin and Na+/K+-ATPase; and up-regulated the levels of mRNAs of some neutral and cationic (non-anionic) amino acid transporter proteins (Solute Carrier Family7member1 (SLC7A7), SLC7A8, etc.) and H+/oligopeptide transporter protein 1 (PepT1) gene and protein levels. In addition, ferulic acid promoted the gene expression levels of protein kinase B (Akt), target of rapamycin (TOR); up-regulated the mRNA levels of tail-side-associated homologous frame transcription factor 2 (Cdx2), cAMP response element-binding protein (CREB), and transcriptional co-activator-specific protein 1 (Sp1), and down-regulated the gene and protein levels of protein kinase CβII (PKCβII). In a word, dietary ferulic acid promoted growth performance, digestion, as well as amino acid and oligopeptide transport capacities. Finally, based on regression analyses of percentage weight gain (PWG), FE, specific growth rate (SGR), intestine fold height, trypsin activity, and Na+/K+-ATPase activity, we recommend optimal supplementation levels of ferulic acid in sub-adult grass carp of 92.18–120.60 mg/kg diet.

Effect of encapsulated Medinilla javanensis fruit extract on growth, protein digestibility and health of broilers

The study investigated the effect of encapsulated Medinilla javanensis fruit extract on performance, protein digestibility, and health of broilers. A total of 200 Cobb broiler chicks were divided into five treatments with four repetitions, including T0 (basal diet), T1 (basal diet + 200 mg/kg encapsulated Medinilla javanensis fruit extract), T2 (basal diet + 400 mg/kg encapsulated Medinilla javanensis fruit extract), T3 (basal diet + 600 mg/kg encapsulated Medinilla javanensis fruit extract), and T4 (basal diet + 800 mg/kg encapsulated Medinilla javanensis fruit extract). Sample collection was conducted on day 35 of age. Results showed that increased encapsulated Medinilla javanensis fruit extract levels in feed linearly increased (P&lt;0.05) body weight, body weight gain, intestinal lactic acid bacteria counts, protein digestibility and serum superoxide dismutase levels, while linearly decreasing (P&lt;0.05) feed conversion ratio, intestinal Escherichia coli counts, small intestinal pH values and serum malondialdehyde levels. In conclusion, encapsulated Medinilla javanensis fruit extract improved growth performance, protein digestibility intestinal health and antioxidant status of broilers. The encapsulated Medinilla javanensis fruit extract at a level of 600 mg/kg exerted the best performance and health of broilers.

Parameter Estimation of Host Genomic and Gut Microbiota Contribution to Growth and Feed Efficiency Traits in Meat Rabbits.

Rabbits can efficiently utilize plant fibers that are indigestible to humans, and hence may contribute to the alleviation of feed-food competition. Therefore, it is economically and ecologically important to genetically improve the growth performance and feed efficiency of meat rabbits. In this study, we combined pedigree, genomic, and gut microbiota data to estimate genetic and microbial parameters for nine growth and feed efficiency traits of 739 New Zealand White rabbits, including body weight (BW) at 35 (BW35), 70 (BW70), and 84 (BW84) days of age, and average daily gain (ADG), feed conversion ratio (FCR), and residual feed intake (RFI) within two age intervals of 35-70 days (ADG70, FCR70, and RFI70) and 35-84 days (ADG84, FCR84, and RFI84). Based on single-step genomic best linear unbiased prediction, three BW traits and two ADG traits had the high estimates (±standard error, SE) of heritability, ranging from 0.44 ± 0.13 of BW35 to 0.66 ± 0.08 of BW70. Moderate heritabilities were observed for RFI70 (0.22 ± 0.07) and RFI84 (0.29 ± 0.07), whereas the estimates did not significantly deviate from zero for the two FCR traits. There was moderate positive genetic correlation (±SE) between BW70 and ADG70 (0.579 ± 0.086), but BW70 did not correlate with RFI70. Based on microbial best linear unbiased prediction, the estimates of microbiability did not significantly deviate from zero for any trait. Based on the combined use of genomic and gut microbiota data, the parameters obtained in this study could help us to implement efficient breeding schemes in meat rabbits.

Dietary silicate minerals relieving cadmium or lead poisoning in juvenile sea cucumber, Apostichopusjaponicus

Industrial activities increase Apostichopus japonicus exposure to toxic heavy metals. This study evaluates the efficacy of three dietary silicate minerals (montmorillonite, zeolite, and kaolin) in relieving cadmium and lead toxicity in A. japonicus. Over four weeks, juvenile A. japonicus (7 − 9 g) were fed diets incorporating montmorillonite, zeolite, or kaolin, replacing sea mud at a 1:1 ratio. Experimental groups were: SM (control with sea mud), M (montmorillonite), Z (zeolite), and K (kaolin). Each group was exposed to cadmium (50 mg kg−1) or lead (100 mg kg−1) at the minimal toxic dose (MTD). Groups M and K demonstrated excellent growth performance, marked by improvements in weight gain rate (WGR), specific growth rate (SGR), feed conversion ratio (FCR), and survival rate (SR). Their coelomic fluid revealed higher enzymatic activities, such as acid phosphatase (ACP), alkaline phosphatase (AKP), catalase (CAT), and superoxide dismutase (SOD). Additionally, groups M and K showed a reduced accumulation of cadmium and lead in their tissues; group K notably excelled in mitigating intestinal tissue damage. In contrast, Group Z exhibited significantly poorer performance. In other aspects, the trends among the three experimental groups were generally similar: the activity of intestinal digestive enzymes declined, intestinal microbiota diversity decreased, and the stability of community composition increased. In summary, the supplementation of montmorillonite and kaolin effectively reduces cadmium and lead toxicity, diminishes oxidative damage, and promotes intestinal health in A. japonicus. These findings provide valuable insights for enhancing safety in A. japonicus aquaculture.

Antibiotics in broilers chicken production: a review of impacts, challenges and potential alternatives

Globally, the use of antibiotic in animal industry was well known in the 20th century. Antibiotics usage as therapeutic and subtherapeutic means of improving growth and feed efficiency in livestock was well documented in literature. However, continuous use of antibiotics in food animals for increased growth and disease prevention has resulted in the development of antibiotic resistant bacteria in animals. This has led to disease treatment failure in the affected animals. The problem of transmission of antibiotic resistant bacteria to human through food chain and contamination of environment is another challenge of antibiotic usage in poultry production. Hence, the ban was placed on antibiotic usage in animal production. The restriction to the use of animal growth promoting antibiotic has gained high compliance in the developed countries. However, in the third world countries, this is still a battle that is on-going. To achieve the 2023 Global Action Plan on Antimicrobial Resistance goal, a lot is still left to be done. This review synthesized information on implications of antibiotics use on broiler chickens’ production cost efficiency and profitability; impact of antibiotics mode of action, diseases prevention and treatments of infection in broiler chickens’ production; challenges of antibiotics residual effect on meat quality and safety and alternatives to synthetic antibiotic for broiler chickens’ production.

Efficacy of Mycotoxin Binder on Broiler Performance, Organ Weight, Wishbone Weight, and Gut Length: A Meta-Analysis

Mycotoxin-contaminated feed is one of the main causes of contamination that may increase broiler mortality and impair their production. A total of 161 in vivo data acquired from 31 published articles were used as a database for determining the effectiveness of mycotoxin binders on performance and health of broiler. The Hedges’ d value was employed as a measure of effect size (ES) in the present meta-analysis. Increasing mycotoxin binder in feed enhanced body weight (ES=0.784; P&lt;0.001), decreased feed conversion ratio (ES=-0.87; P&lt;0.001), and decreased mortality (ES=-3.98; P&lt;0.001). In terms of average daily gain and mortality suppression, the finisher phase demonstrated the greatest effectiveness of the binder usage compared to the starter and finisher phases. The effectiveness of binders in lowering the incidence of mycotoxin in feed was beneficial in reducing mortality and enhancing broiler performance. In addition, its application into feed may enhance the health condition of broilers by enhancing organ weights and gastrointestinal health.

Differential expression of nuclear-derived mitochondrial succinate dehydrogenase genes in metabolically active buffalo tissues.

Buffaloes are crucial to agriculture, yet mitochondrial biology in these animals is less studied compared to humans and laboratory animals. This research examines tissue-specific variations in mitochondrial succinate dehydrogenase (SDH) gene expression across buffalo kidneys, hearts, brains, and ovaries. Understanding these variations sheds light on mitochondrial energy metabolism and its impact on buffalo health and productivity, revealing insights into enzyme regulation and potential improvements in livestock management. RNA-seq data from buffalo kidney, heart, brain, and ovary tissues were reanalyzed to explore mitochondrial SDH gene expression. The expression of SDH subunits (SDHA, SDHB, SDHC, SDHD) and assembly factors (SDHAF1, SDHAF2, SDHAF3, SDHAF4) was assessed using a log2 fold-change threshold of + 1 for up-regulated and - 1 for down-regulated transcripts, with significance set at p < 0.05. Hierarchical clustering and differential expression analyses were performed to identify tissue-specific expression patterns and regulatory mechanisms, while Gene Ontology and KEGG pathway analyses were conducted to uncover functional attributes and pathway enrichments across different tissues. Reanalysis of RNA-seq data from different tissues of healthy female buffaloes revealed distinct expression patterns for SDH subunits and assembly factors. While SDHA, SDHB, and SDHC showed variable expression across tissues, SDHAF2, SDHAF3, and SDHAF4 exhibited tissue-specific profiles. Significant up-regulation of SDHA, SDHB, and several assembly factors was observed in specific tissue comparisons, with fewer down-regulated transcripts. Gene ontology and KEGG pathway analyses linked the up-regulated transcripts to mitochondrial ATP synthesis and the respiratory electron transport chain. Notably, tissue-specific variations in mitochondrial function were particularly evident in the ovary. This study identifies distinct SDH gene expression patterns in buffalo tissues, highlighting significant down-regulation of SDHA, SDHB, SDHC, and assembly factors in the ovary. These findings underscore the critical role of mitochondria in tissue-specific energy production and metabolic regulation, suggest potential metabolic adaptations, and emphasize the importance of mitochondrial complex II. The insights gained offer valuable implications for improving feed efficiency and guiding future research and therapies for energy metabolism disorders.

Effects of Increasing Oral Deoxynivalenol Gavage on Growth Performance, Blood Biochemistry, Metabolism, Histology, and Microbiome in Rats.

Mycotoxin-contaminated feed or food can affect physiological responses and cause illnesses in humans and animals. In this study, we evaluated the effects of deoxynivalenol (DON) toxicity on the growth performance, blood biochemistry, histology, microbiome, and metabolism of rats fed with different toxin concentrations. After 1 week of acclimatization, seven-week-old male rats received 0.9% saline as a control, 0.02 mg/kg DON as T1, and 0.2 mg/kg DON as T2 via oral gavage for 4 weeks. The final body weight of the T2 group was significantly lower than that of the control and T1; however, the average daily gain, feed intake, and feed conversion ratio did not differ. Fibrosis and apoptosis were observed in various tissues as DON concentration increased. Creatinine and alkaline phosphatase levels were significantly lower in the DON-treated group than in the control. Firmicutes and Desulfobacterota phyla dominated the cecum, whereas those in the feces were Proteobacteria and Bacteroidetes. Metabolomic profiling showed phenylalanine, tyrosine, and tryptophan biosynthesis as the most prominent pathways. Overall, our results suggest that low-dose and short-term DON exposure can trigger several adverse effects in rats. Dietary toxicants in rats may explain the physiological effects associated with the metabolism commonly reported in animals.

A review of the global use of fishmeal and fish oil and the Fish In:Fish Out metric.

Aquacultured carnivorous species consume most of the world's fishmeal and fish oil (FMFO), which itself is primarily derived from small pelagic fish. This has raised concerns about the practice's impact on wild fish stocks, ecosystems, and coastal communities that rely on these fish. The aquaculture industry claims a decreasing dependence on wild fish, relying on the Fish In:Fish Out (FIFO) metric as a ratio of the quantity of wild fish required for farmed fish production. This is misleading because it usually assumes constant FM or FO yields, inclusion rates and feed conversion ratios, which vary widely. Thus, a constant FIFO value for a given species cannot be assumed. Furthermore, low FIFO values resulting from averaging carnivores and herbivores conceal the high feed requirements of carnivore species. The increasing use of FMFO from by-products does not demonstrate a decreased use of wild fish but rather reflects a growing demand for FMFO, particularly for the fast growing and valuable salmon and shrimp farming industries.

Investigating the effects of wild olive Olea europaea leaf extract on growth, body composition, digestive enzyme activity, hematological parameters, and immune function in Nile Tilapia

AbstractObjectiveThis study investigated the effects of supplementing Nile Tilapia Oreochromis niloticus diets with wild olive Olea europaea leaf extract (WLE) on growth performance, digestive enzymes, and antioxidant and immunological parameters.MethodsWild olive leaf extract was added at different concentrations (WLE 0.0 [control], 1.0, 1.5, and 2.0%) and fed to triplicate fish groups for 12 weeks. At the end of the trial period, growth performance, body composition, digestive enzyme activities, and hematological, biochemical, antioxidant, and immunological parameters were evaluated.ResultAccording to the results, fish that were fed with WLE 1.5% and WLE 2.0% exhibited significantly improved weight gain, specific growth rate, and feed intake. The feed conversion ratio (FCR) was significantly reduced in fish supplied with WLE 1.5% and WLE 2.0%. Additionally, weight gain and FCR showed significance at both the linear and quadratic levels, as indicated by polynomial contrasts. However, the experimental diets did not impact fish body composition, digestive enzyme activity, or survival rate. Fish that received WLE 1.5% and WLE 2.0% showed significantly higher levels of white blood cells, red blood cells, hemoglobin, and hematocrit compared with the WLE 1.0% and control groups. Moreover, significant enhancements were observed in serum parameters, including total protein, albumin, globulin, lysozyme, catalase, superoxide dismutase, and total immunoglobulins, for the WLE 1.5% and WLE 2.0% groups compared with the control. Fish that were fed WLE 1.5% exhibited the lowest serum cortisol level.ConclusionIn conclusion, experimental diets with WLE levels of 1.5% and 2.0% effectively enhanced both the growth and immunological parameters of Nile Tilapia.

Effects of dietary rosemary (Rosmarinus officinalis) leaf powder and Bacillus subtilis on the growth performance, digestive enzymes, antioxidant and immune-related gene expression, and resistance to Aeromonas hydriphila in common carp, Cyprinus carpio

Abstract Due to increasing demand about the application of natural feed additives in aquaculture, the efficacy of separate and the combination of rosemary (Rosmarinus officinalis) and B. subtilis on the growth performance, blood indices, innate immunity, antioxidant defense, digestive enzymes activity, the expression levels of genes with immunity modulation, as well as the act of resisting against Aeromonas hydriphila, in common carp, C. carpio is reported. Fish (44.63 ± 0.04 g) were divided into four treatments including the T0 (control treatment) fed with basal diet, T1 fed with rosemary at the rate of 3 %, T2 fed with 1.5×107 CFU g-1 B. subtilis, and T3 fed with a combination of rosemary at the rate of 3 % and 1.5×107 CFU g-1 B. subtilis. After 56 days enriched feed with B. subtilis and combination of rosemary and B. subtilis caused significant improvement in weight gain (WG %), feed conversion ratio (FCR), hematological and biochemical indices, the innate immune responses including in total Ig level, lysozyme and ACH50 activities as well as the chymotrypsin, pepsin, protease, and amylase activities correlate to the control group (P&lt;0.05). Additionally, the serum CAT and GPX activity were significantly enhanced in the T3 group (P&lt;0.05). The mRNA expression of CAT and LYS genes significantly increased in T2 and T3 contrary to T0 (p&lt;0.05). Fish challenged with A. hydrophila had variable survival and the best survival was in the T3. In summary, combination the rosemary and B. subtilis enhanced immune parameters and the ability of fish to cope with A. hydrophila as a fish pathogen. These findings indicated the potential of these substances as a promising feed additive.

Effect of Long-Term Supplementation of AZOMITE (Hydrated Sodium Calcium Aluminosilicate) in Finishing Diets on Growth Performance, Dietary Energy, and Carcass Yield of Hairy Lambs.

The aim of this study was to evaluate growth performance, dietary energy utilization, and carcass characteristics (carcass weight, dressing percentage, and visceral organ mass) of feedlot lambs fed different levels of AZOMITE (AZO), a source of volcanic clay composed of hydrated sodium calcium aluminosilicate, the same as that included in a finishing diet. For this reason, 36 Pelibuey × Katahdin crossbred intact male lambs (18.81 ± 3.04 kg initial weight) were used in a feeding trial lasting 81 d. Lambs were grouped by initial weight and assigned within six weight groupings to 18 pens in a randomized complete block design. Diets, offered ad libitum, were corn-based finishing diets with an 88:12 concentrate-to-forage ratio supplemented as follows: 1) no AZO inclusion (CTRL), 2) AZO inclusion at a 0.75% level (0.75AZO) in diet dry matter, 3) AZO inclusion at a 1.50% level (1.5AZO) in diet dry matter. Cracked corn was replaced by AZO. After the feeding trial was finished, lambs were slaughtered and carcass weight was registered and dressing percentage was calculated. The data were analyzed as a randomized complete block design, with the pen as the experimental unit. Water consumption and dry matter intake were not affected (p ≥ 0.11) by supplemental AZO. The incorporation of AZO into the diet increased gain efficiency and observed dietary net energy (NE), being maximal with 0.75% AZO inclusion (quadratic effect, p = 0.02). The observed-to-expected dietary NE in the control group was as anticipated (1.00) according to the estimated energy based on the ingredient composition in diet, while in the 0.75AZO group, the observed dietary energy was 6% above expected, indicating a greater efficiency in energy utilization destined to growth (quadratic effect, p = 0.006). Lambs that were fed the AZO treatment showed an improvement (linear effect, p = 0.04) in hot carcass weight (HCW), and tended (linear effect, p = 0.06) to improve dressing percentage (DP) as AZO was increased in the diet. Visceral organ mass was not affected by the treatments. It is concluded that AZOMITE clay can be included up to 1.5% in finishing diets for lambs without negative effects on the intake of water and feed. Lambs that received diets supplemented with 0.75% AZO showed greater improvements in feed efficiency and dietary energy utilization, but an inclusion of 1.50% resulted in greater improvements to HCW and DP. This is the first report regarding the effects of AZO supplementation in the dietary energy utilization of fattening hairy lambs. Further research about the effects of AZO supplementation on ruminal and total tract digestion, carcass and meat quality, and the health of lambs is needed in order to more deeply understand the effects of AZO on its productivity performance.

Nutritional Value of Oregano-Based Products and Its Effect on Rabbit Performance and Health.

Antimicrobials long been used to enhance the performance and immunity of rabbits, typically by adding them to feed or drinking water to prevent illness. However, increasing consumer concerns about antibiotic-resistant microorganisms have led to a shift toward natural, eco-friendly, non-antibiotic feed supplements that can improve rabbit health and productivity. Recently, aromatic herbs and their extracts have gained considerable attention as natural antioxidants with growth-promoting and health-boosting properties. Essential oils and secondary metabolites play a central role in these effects, with Origanum vulgare (oregano) emerging as a standout option. Compared to synthetic alternatives, oregano is a natural, residue-free feed supplement with fewer harmful side effects. Its key bioactive components, thymol and carvacrol, have been shown to deliver significant benefits when incorporated into rabbit diets, particularly in improving production performance, immunity, and antioxidant capacity. Supplementing rabbit diets and drinking water with oregano essential oil (OEO) has been found to enhance growth performance, feed efficiency, and meat quality, while also lowering cholesterol levels and boosting antioxidant activity. Despite these promising results, research on the use of oregano in rabbit farming remains limited. This review aims to provide an up-to-date overview of the potential effect of oregano supplements, on growth parameters, carcass and meat quality, hemato-biochemical parameters, antioxidant capacity, immunity response, gut health, and gene expression in rabbits.

Eucommia ulmoides Oliv. leaf extract: Effects on growth, antioxidant capacity, and lipid metabolism in Red swamp crayfish (Procambarus clarkii)

The addition of Eucommia ulmoides Oliv. leaf extract (ELE) enhances growth, immunity and antioxidant capacity in crustaceans, which has not been studied on the red swamp crayfish (Procambarus clarkii). Hence, this study aimed to investigate the effect of ELE on the growth, antioxidant capacity, digestive enzymes activities, and lipid metabolism of red swamp crayfish. A total of 240 individuals of red swamp crayfish were randomly assigned to four groups. Each group was fed with feed a diet supplemented with varying doses of ELE: 0 g/kg (CK), 0.5 g/kg (T2), 1.0 g/kg (T3), and 1.5 g/kg (T4). After 30 days, the results indicated that T2 group exhibited a significantly higher final average weight, weight gain rate, and specific growth rate compared to the CK (P<0.05). Significantly lower feed conversion ratios than the CK (P<0.05) were observed in the T2 and T3 groups. For antioxidant indicators, hepatopancreas superoxide dismutase (SOD) activity was observed to significantly increased in the T3 and T4 groups, while levels of malondialdehyde (MDA) in which were significantly reduced in hepatopancreas and hemolymph (P<0.05). Regarding biochemical indicators and intestinal function, significant enhancement of lipase (LPS) activity was observed in the T2 group, which decreased in the T4, compared to the CK (P<0.05). Moreover, significant decrease of the glucose (GLU), total triglyceride (TG), and total cholesterol (TC) content of the hemolymph (P<0.05) were observed in the T4 group. Transcriptome analysis revealed that differentially expressed genes in the T4 group were primarily enriched in peroxisome proliferator-activated receptor (PPAR), and lipid metabolism pathways. Furthermore, it seems that ELE supplements significantly upregulated the expression of apoa-II, acaox1, acox3, me1, and plin1 in the PPAR signaling pathway to regulate lipid metabolism. In conclusion, 0.5 g/kg and 1.5 g/kg ELL addition amount can enhance growth performance, antioxidant capacity, and lipid metabolism of red swamp crayfish.