Dietary Addition Research Articles

Effects of dietary supplementation of Bacillus, β-glucooligosaccharide and their synbiotic on the growth, digestion, immunity, and gut microbiota profile of abalone, Haliotis discus hannai

Probiotics, prebiotics, and synbiotics are known to improve aquatic animals' growth and health conditions. In this study, we investigated the effect of Bacillus sp. KRF-7 (KRF-7), Bacillus sp. PM8313 (PM8313), β-glucooligosaccharide (BGO), and their synbiotics on the growth, digestive physiology, immunity, and gut microbiota of abalone, Haliotis discus hannai. The control diet (CON) was sprayed with 108 CFU/g KRF-7 (PRO1) or PM8313 (PRO2) as probiotics, 0.10% BGO (PRE) as prebiotic, and their combinations (SYN1: PRO1 + BGO; SYN2: PRO2+ BGO) as synbiotic treatments. These diets (triplicates) were given once daily to the abalone (initial body weight: 1.32 ± 0.05 g, initial shell length: 21. 69 ± 0.19 mm) for 12 weeks. The results showed that the PRE diet induced a significant 15% shell length and body weight increase against the CON (SLGR: 45.77% vs. 53.04%; WGR: 182.77% vs. 210.22%), the highest among dietary supplements (P < 0.05). The level of IGF and IGFBP in the cell-free hemolymph, protein expression of IGF signaling, and gene expression of myosin heavy chain in the adductor muscle increased significantly (P < 0.05) following dietary supplementation. Correspondingly, PRE-, PRO1-, and PRO2-fed abalone had the highest trypsin, lipase, and amylase secretion in the hepatopancreas (P < 0.05) and increased histomorphometry (stomach epithelial thickness and intestinal villi height) (P < 0.05). Regarding antioxidative capacity and immunity, the hepatopancreatic expression of SOD, CAT, IRAK-4, NF-Kb, TNF-α, and β-defensin were significantly upregulated in abalone fed with dietary additives compared to the CON (P < 0.05). In terms of gut microbiota profile, PRE-fed abalone had a significant reduction in microbial richness (P < 0.05). The phylum level was similarly occupied, while a diet-specific core microbiota at the genus level was apparent. The findings illustrated that BGO, KRF-7, and PM8313 can be used in abalone aquaculture as growth-promoting and immune-stimulating supplements.

Comparative Effects of Including Inorganic, Organic, and Hydroxy Zinc Sources on Growth Development, Egg Quality, Mineral Excretion, and Bone Health of Laying Quails.

The purpose of this study was to determine the effects of the dietary addition of zinc (Zn) in the form of sulphate (Zn-S), glycine (Zn-G), and hydroxychloride (Zn-H) on quail performance, eggshell quality, antioxidant status, mineral excretion, biomechanical properties and mineralization of bone. A total of 75 female quails (10-weeks-old) were randomly distributed into 3 groups with 5 replications, each with 5 female quails. Treatment groups were set up by adding Zn-S and Zn-H as the inorganic form and Zn-G as the organic form of zinc to the corn-soybean basal diet (34.14mg/kg Zn) to obtain 50mg/kg Zn and the feeding experiment lasted for 12 weeks. Performance parameters and egg production were not impaired by the Zn source (P > 0.05). The inclusion of Zn-S in the diet produced a reduction in eggshell thickness, while an improvement in yolk antioxidant capacity (measured as MDA concentration) was detected compared to the other Zn sources (P < 0.05). Shear strength and cortical bone area increased (P < 0.05) with Zn-G supplementation, however, the mineral concentration of the tibia was higher (P < 0.01) in those quails who had received Zn-H. Lower levels of mineral excretion were observed in both types of supplementations compared to Zn-S. Therefore, it can be stated that Zn-G or Zn-H supplementation in the diet of laying quails could be an interesting strategy to reduce mineral excretion and improve bone mineralization without affecting performance compared to Zn-S. However, further studies are needed to determine the differences between Zn-G and Zn-H.

Interactions between maternal parity and feed additives drive the composition of pig gut microbiomes in the post-weaning period

BackgroundNursery pigs undergo stressors in the post-weaning period that result in production and welfare challenges. These challenges disproportionately impact the offspring of primiparous sows compared to those of multiparous counterparts. Little is known regarding potential interactions between parity and feed additives in the post-weaning period and their effects on nursery pig microbiomes. Therefore, the objective of this study was to investigate the effects of maternal parity on sow and offspring microbiomes and the influence of sow parity on pig fecal microbiome and performance in response to a prebiotic post-weaning. At weaning, piglets were allotted into three treatment groups: a standard nursery diet including pharmacological doses of Zn and Cu (Con), a group fed a commercial prebiotic only (Preb) based on an Aspergillus oryzae fermentation extract, and a group fed the same prebiotic plus Zn and Cu (Preb + ZnCu).ResultsAlthough there were no differences in vaginal microbiome composition between primiparous and multiparous sows, fecal microbiome composition was different (R2 = 0.02, P = 0.03). The fecal microbiomes of primiparous offspring displayed significantly higher bacterial diversity compared to multiparous offspring at d 0 and d 21 postweaning (P < 0.01), with differences in community composition observed at d 21 (R2 = 0.03, P = 0.04). When analyzing the effects of maternal parity within each treatment, only the Preb diet triggered significant microbiome distinctions between primiparous and multiparous offspring (d 21: R2 = 0.13, P = 0.01; d 42: R2 = 0.19, P = 0.001). Compositional differences in pig fecal microbiomes between treatments were observed only at d 21 (R2 = 0.12, P = 0.001). Pigs in the Con group gained significantly more weight throughout the nursery period when compared to those in the Preb + ZnCu group.ConclusionsNursery pig gut microbiome composition was influenced by supplementation with an Aspergillus oryzae fermentation extract, with varying effects on performance when combined with pharmacological levels of Zn and Cu or for offspring of different maternal parity groups. These results indicate that the development of nursery pig gut microbiomes is shaped by maternal parity and potential interactions with the effects of dietary feed additives.

Prophylactic and Therapeutic Efficacy of Ultrasonicated Rosmarinus officinalis Ethanolic Extract and its Chitosan-Loaded Nanoparticles Against Eimeria tenella Infected Broiler Chickens

PurposeThe in vivo efficacy of ultrasonicated Rosmarinus officinalis ethanolic extract (UROEE) and its chitosan-loaded nanoparticles (UROEE-CsNPs) was investigated as a dietary prophylactic agent and as a therapeutic treatment against Eimeria tenella infected broiler chickens.MethodsChickens were infected with 4 × 104E. tenella oocysts at 21 days old for primary infection and with 8 × 104 oocysts at 35 days old for secondary infection. Eleven experimental groups were conducted. Dietary addition of 100 mg/kg UROEE and 20 mg/kg for CsNPs as well as UROEE-CsNPs were included for prophylactic groups from day 1 to 42. The same doses were used for therapeutic treatment groups for 5 constitutive days. Oocyst output in feces was counted. Histopathological and immunohistochemical studies were conducted. Gene expression of pro-inflammatory cytokines as IFN-γ, IL-1β and IL-6 as well as anti-inflammatory cytokines as IL-10 and TGF-β4 was analyzed using semi-quantitative reverse transcriptase-PCR.ResultsThe results showed an efficacy of UROEE, CsNPs and UROEE-CsNPs in reduction of oocyst excretion and improving the cecal tissue architecture. CD4+ and CD8+ T lymphocytes protein expression were reduced. E. tenella infection lead to upregulation of pro-inflammatory cytokines as IFN-γ, IL-1β, IL-6 and anti-inflammatory cytokines as TGF-β4 following primary infection, while their expression was downregulated following secondary infection.ConclusionThe dietary prophylactic additives and therapeutic treatments with UROEE, CsNPs and UROEE-CsNPs could decrease the inflammatory response to E. tenella as indicated by oocyst output reduction, histopathological improvements, CD4+ and CD8+ T cells protein expression reduction as well as reducing mRNA expression levels of the tested cytokines following primary and secondary infections. Consequently, these results will help to develop better-combating strategies for the control and prevention of coccidiosis on poultry farms as a dietary prophylactic agent or as a therapeutic treatment.Graphical

Physiological Responses, Oxidative Status and Productive Performance of Barki Sheep fed Dietary Addition with Quinoa Seeds and Exposed to Solar Radiation

Physiological Responses, Oxidative Status and Productive Performance of Barki Sheep fed Dietary Addition with Quinoa Seeds and Exposed to Solar Radiation

Exploring the Antioxidant Properties of Citrus limon (Lemon) Peel Ultrasound Extract after the Cloud Point Extraction Method

Each year, a substantial amount of food is discarded around the globe. A significant portion of this waste consists of by-products derived from Citrus fruits such as lemons. The purpose of this research is to examine the polyphenol extraction and the antioxidant ability of lemon peel using cloud point extraction (CPE), a sustainable approach. CPE was conducted using three steps with a 20% w/v concentration of Span 20 as the surfactant, which has a critical micellar concentration of 6.13 × 10−5 mol/L. The pH was set at 7 and a salt concentration of 20% was maintained at 45 °C for 20 min. The subsequent outcomes of the analysis were obtained: total polyphenol content (TPC): 526.32 mg gallic acid equivalents per liter; total flavonoid content (TFC): 90.22 mg rutin equivalents per liter; FRAP, DPPH, and hydrogen peroxide assays: 2.40, 2.68 and 1.03 mmol ascorbic acid equivalents per liter, respectively, and 168.63 mg/L ascorbic acid content. The quantification of the polyphenolic compounds through High-Performance Liquid Chromatography showed that the most abundant compounds in the lemon peels are eriocitrin (159.43 mg/L) and hesperidin (135.21 mg/L). The results indicate that the proposed CPE technique is successful in extracting antioxidant compounds from lemon peels. The generated extracts have the potential to be exploited as dietary additives to enhance human health and can also be utilized for nutraceuticals or pharmaceutical purposes.

Selenomethionine Supplementation Mitigates Liver Dysfunction, Oxidative Injury and Apoptosis through Enhancing Antioxidant Capacity and Inhibiting JNK MAPK Pathway in Piglets Fed Deoxynivalenol-Contaminated Diets.

This research evaluated the impacts of selenomethionine (Se-Met) on hepatic functions, oxidative stress, mitochondrial function, and apoptosis of piglets fed deoxynivalenol (DON)-contaminated diets. Twenty-four piglets were allocated four dietary treatments (n = 6) in a 28-day feeding trial. The four treatments included the control group, which received 0.3 mg/kg of Se (as Se-Met) without DON treatment, and the DON treatment groups received 0, 0.3, or 0.5 mg/kg Se as Se-Met. A dietary addition of 0.5 mg/kg Se improved liver pathology and reduced serum aspartate aminotransferase and lactate dehydrogenase levels in piglets fed DON-contaminated diets. Furthermore, 0.5 mg/kg Se mitigated the oxidative stress and apoptosis of piglets fed DON-contaminated diets, as indicated by the decreased reactive oxygen species level, and the down-regulated mRNA levels of NRF-1, Bax, and CASP9 in the liver. Importantly, 0.5 mg/kg Se enhanced the hepatic antioxidant capacity, as evidenced by increased hepatic total antioxidant capacity, catalase, glutathione peroxidase, and total superoxide dismutase activities, as well as the up-regulated mRNA levels of Nrf2, Gclm, NQO1, SOD1, and GPX1 in the liver. Moreover, 0.5 mg/kg Se down-regulated the p-JNK protein level in the liver of piglets fed DON-contaminated diets. Collectively, Se-Met supplementation mitigated liver dysfunction, oxidative injury, and apoptosis through enhancing antioxidant capacity and inhibiting the JNK MAPK pathway in piglets fed DON-contaminated diets.

Dietary supplementation with mushroom powder (Agaricus bisporus) on performance, carcass traits, meat quality, and bone biomechanical properties of quail (Coturnix coturnix japonica)

This study was performed to determine the effect of mushroom powder (MP) (Agaricus bisporus) supplementation on growing Japanese quail (Coturnix coturnix japonica). A total of 300 unsexed 1-day-old Japanese quails with similar body weights (8.38 ± 0.2 g) were randomly assigned to five treatment groups with six replications. Additions of 0, 0.25, 0.50, 0.75, or 1.00% of MP to the basal diet were used to develop the treatment groups. Quails were fed ad libitum for 42 days. At the end of the experiment, 12 quails from each experimental unit were euthanised to determine performance, carcass traits, meat quality, and bone biochemical properties. Results showed that all dietary MP did not negatively affect any performance parameters (P > 0.05), while by the third week of life, there was an increase (P < 0.05) in body weight and body weight gain in the quails of the 0.75% MP group compared to the control group. Nevertheless, these differences disappeared at the end of the trial (P > 0.05). No differences were observed (P > 0.05) for any of the studied carcass traits, except for the pancreas weight which decreased (P < 0.05) with the addition of high MP (1.00%). Regarding meat quality, all color parameters were affected on the fifth day of sampling (P < 0.05) but not on the first day (P > 0.05). It was detected that the breast of the quails in group 0.75% MP had the highest L* value and the lowest a* value. While the breast of the 1.00% MP group had the highest b value and the lowest pH value. Dietary MP enhanced oxidative stability, reducing malondialdehyde (MDA) value in the breast compared to the control at both sampling points (P < 0.01), being more noted on the fifth day of sampling. Bone biomechanical properties (in terms of shear force or shear stress) were improved (P < 0.01) with the dietary addition of MP at 0.75% compared to the control. It can be suggested that MP is a secure ingredient in animal feed without negatively affecting performance parameters, carcass traits, or meat quality. Therefore, including an interval of 0.50–0.75% of MP in the diet of growing quails could be a suitable strategy to improve certain parameters such as the meat’s oxidative stability and the bone’s biomechanical parameters. Moreover, the efficacy of MP on performance development would be greater during the first weeks of the quails’ life due to their intestinal conditions at this stage.

Metabolomics-based study of the effect of dietary N-carbamoylglutamic acid addition to heifers in late pregnancy on newborn calves.

It has been demonstrated that supplementing late-gestation cow diets with NCG (N-carbamoylglutamic acid) increases the serum protein level, boosts immunological function, and increases the birth weight of the calves. However, the underlying mechanism remains unclear. In this experiment, 30 late-gestation Angus heifers almost at same conditions were chosen for this experiment. They were randomly divided into two groups of 15 cows each. A basal diet was provided to the control group, and 30 g/(d-head) of NCG was added to the basal diet of the test group (NCG group). Blood samples were collected from the jugular vein after birth and before the end (when the calves were 90 days old) of the experiment for plasma metabolomics analysis. The metabolomics analysis identified 53 metabolites between the NCG group and control group, with 40 significantly up-regulated and 13 significantly down-regulated. Among them, 33 lipids and lipid-like molecules made up 57.89% of all the metabolites that were found. Thirty-three metabolic pathways enriched by metabolites showed p.adjust <0.05, among which glycerophospholipid and sphingolipid metabolism pathways were the most abundant. In conclusion, the addition of NCG in late-gestation cows appears to primarily affect calf growth and development through the regulation of phospholipid metabolism, which plays a role in nerve conduction, brain activity, and cell metabolism and function. This study provides valuable insights into how nutritional supplementation by late-gestation cows might improve the growth and development of newborn calves.

Determination of sweetener specificity of horse gut-expressed sweet taste receptor T1R2-T1R3 and its significance for energy provision and hydration.

Studies carried out in several species have demonstrated that detection of low-calorie sweeteners in the lumen of the intestine, by the sweet receptor, T1R2-T1R3, initiates a signaling pathway leading to enhanced expression and activity of intestinal Na+/glucose cotransporter 1, SGLT1. This results in an increased gut capacity to absorb glucose, sodium chloride and water, the basis for oral rehydration therapy. Horses express T1R2, T1R3 and downstream signaling elements in the intestinal tissue. As such, the potential of sweetener-stimulation of T1R2-T1R3 leading to upregulation of SGLT1 allows the provision of more glucose (energy) and hydration for horses. This is especially important when the need for glucose increases during strenuous exercise, pregnancy, and lactation. There are significant differences among species in the ability to detect sweeteners. Amino acid substitutions and pseudogenization of taste receptor genes underlie these variations. Nothing is known about the sweetener specificity of horse T1R2-T1R3. Using heterologous expression methodology, we demonstrate that sweeteners sucralose, stevia and neohesperidin dihydrochalcone (NHDC) activate horse T1R2-T1R3, but cyclamate does not. Determination of sweetener specificity of equine sweet receptor is crucial for developing suitable dietary additives to optimize glucose absorption, hydration and avoiding the intestinal disease brought about by microbial fermentation of unabsorbed carbohydrate reaching the large intestine.

Hippocampus and jejunum biochemical parameters related to physiological ageing of neurons in rats fed diets with copper nanoparticles and different fiber types

Abstract One of the more important factors responsible for synaptic dysfunction of neurons is a neurological ageing. It is a natural consequence of occurrence of biochemical pathways in cells, promoting oxidation processes, an increase in the amount of free oxygen radicals that damage DNA, disorders in calcium ion homeostasis, interactions between lipids of cell membranes, formation of neurofibrillary tangles and deposition of toxic protein deposits. Diet modifications can delay neurometabolism disorders that occur as a result of aging, as well as limit the development of neurodegenerative diseases. The aim of this study on rats was to verify the hypothesis regarding the effect of dietary addition of copper nanoparticles (CuNPs; instead of standard CuCO3) in combination with various dietary fibers on changes in hippocampus and jejunum biochemical parameters related to metabolic disorders appearing with neurological ageing in rats. Male rats were fed a control diet with containing fiber α-cellulose and a standard or enhanced content of Cu provided as CuCO3 (6.5 or 13 mg/kg diet). The diets of other groups were deprived of CuCO3 and the animals were fed diets supplemented with two CuNPs aforementioned doses, and additionally combined with four different types of dietary fiber: α-cellulose (control fiber), pectin, inulin or psyllium (Plantago psyllium). The addition of dietary CuNPs increased the level of acetylcholinesterase (AChE) and decreased the levels of Tau protein, glycosylated AChE (GAChE) and Ca/calmodulin dependent protein kinase II alpha (CAMK2α) in the examined organs. To sum up, both applied doses of CuNPs, 6.5 mg and 13 mg per kg of a diet, can beneficially modulate some important parameters describing metabolic and neurodevelopmental status in the hippocampal and small intestinal tissue of rats. With regard to the fiber type added to rats’ diet, the Plantago psyllium fiber strengthened the mentioned effects of copper nanoparticles. The observed effects should be confirmed in a model study of neurodegeneration.

Response of broilers to dietary inclusion of atoxigenic Aspergillus flavus strain as a biocontrol strategy of aflatoxin

ABSTRACT The objective of this trial was to evaluate how broilers responded to Aspergillus flavus strains that are toxigenic and atoxigenic. The study included four treatments in a 2 × 2 factorial design, with six replicates of 10 birds each. As a result of this study measuring feed intake (FI), weight gain (WG), feed conversion ratio (FCR), crude protein, ether extract, and crude fibre, the interaction was insignificant between the toxigenic and atoxigenic diets (P > 0.05). Consumption of toxigenic aflatoxin B1-500 ppb diet decreased FI and WG but increased FCR, and cost to produce live broiler weight (P < 0.05) compared to the control diets. The addition of atoxigenic strains to contaminated diets significantly offset (P < 0.05) the effects. Diets with or without 500 ppb toxigenic and atoxigenic A. flavus did not affect the relative weight g/100gBW of pancreas, gizzard and bursa of Fabricius. Dietary inclusion of 500 ppb toxigenic Aspergillus spp. increased the relative weight (P < 0.05) of the kidney, liver, spleen and thymus while atoxigenic dietary addition reduced the relative weight of the same organs (P < 0.05). Dietary inclusion of toxigenic and atoxigenic Aspergillus spp. did not significantly affect the haematological parameters measured (P < 0.05). Dietary inclusion of 500 ppb toxigenic Aspergillus elevated the urea, creatine, alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) in the serum of the broilers (P < 0.05). A decrease was observed when atox igenic A. flavus was used in the intervention for urea, creatinine and AST (P < 0.05), whereas an insignificant reduction was observed for ALT and ALP (P ≤ 0.05). This study concluded that dietary atoxigenic strain improved broiler performance, digestibility, and blood parameters.

Nanoliposome-loaded phenolics from Salvia leriifolia Benth and its anticancer effects against induced colorectal cancer in mice.

Colon cancer is one of the leading causes of death among various types of cancer. Despite the significant progress made in cancer treatment, chemotherapy resistance and various side effects are still prevalent. The objective of this study is to assess the therapeutic potential of phenolic-rich fraction encapsulated nanoliposome (PRF-NLs) of Salvia leriifolia Benth in the treatment of colon cancer in mice. Initially, the phenolic-rich fraction (PRF) was extracted and then encapsulated into nanoliposomes. The physicochemical properties of the nanoliposomes were evaluated using dynamic light scattering, zeta potential, and field emission scanning electron microscopy. Subsequently, 24 mice with HT-29 colon cancer cells were divided into three groups, and the anticancer effects of PRF-NLs were measured. The results showed that the ethyl acetate fraction of S. leriifolia was the highest PRF containing 14.27 ± 2.39mg (gallic acid) GA/g DW (dry weight), and the PRF successfully loaded into the nanoliposome structure resulted in the synthesis of nanoliposomes with a nanometer size and spherical shape and homogenous dispersion. Some of the abundant bioactive phenolic compounds in the nanoliposome-loaded PRF are salicylic acid and naringin. The average daily weight gain and food intake, and changes in the expression of caspase 3, Bax (Bcl-2 associated X-protein), and Bcl2 (B-cell lymphoma 2), inducible nitric oxide synthase genes, were observed in the mice group induced colorectal cancer cells. At a dose of 100mg TPC (total phenolic content)/kg BW/day, the nonencapsulated PRF dietary addition improved these parameters; however, the potential shown by nanoliposome-encapsulated PRF than the nonencapsulated PRF in enhancing health parameters in mice was higher. The developed intestinal absorption and bioavailability of nanoliposome-encapsulated PRF contribute to its increased health-promoting activity. Thereby, the synthesized nanoliposome may be a potential natural anticancer drug to prevent colorectal cancer.

Effects of dietary addition of ellagic acid on rumen metabolism, nutrient apparent digestibility, and growth performance in Kazakh sheep.

Plant extracts have shown promise as natural feed additives to improve animal health and growth. Ellagic acid (EA), widely present in various plant tissues, offers diverse biological benefits. However, limited research has explored its effects on ruminants. This study aimed to investigate the effects of dietary addition EA on rumen metabolism, apparent digestibility of nutrients, and growth performance in Kazakh sheep. Ten 5-month-old Kazakh sheep with similar body weight (BW), fitted with rumen fistulas, were randomly assigned to two groups: the CON group (basal diet) and the EA group (basal diet + 30 mg/kg BW EA). The experiment lasted 30 days, and individual growth performance was assessed under identical feeding and management conditions. During the experimental period, rumen fluid, fecal, and blood samples were collected for analysis. The results indicated a trend toward increased average daily gain in the EA group compared to the CON group (p = 0.094). Compared with the CON group, the rumen contents of acetic acid and propionic acid were significantly increased in the EA group and reached the highest value at 2 h to 4 h after feeding (p < 0.05). Moreover, the relative abundances of specific rumen microbiota (Ruminococcaceae, uncultured_rumen_bacterium, unclassified_Prevotella, Bacteroidales, Bacteroidota, Bacteroidia, unclassified_Rikenellaceae, and Prevotella_spBP1_145) at the family and genus levels were significantly higher in the EA group (p < 0.05) compared to the CON group. The EA group exhibited significantly higher dry matter intake (p < 0.05) and increased the digestibility of neutral detergent fiber and ether extract when compared with the CON group (p < 0.05). Additionally, the plasma activities of total antioxidant capacity (T-AOC), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) were significantly higher, while malondialdehyde (MDA) concentration was significantly lower in the EA group compared to the CON group (p < 0.05). In conclusion, dietary supplementation with 30 mg/kg BW EA in 5-month-old Kazakh sheep increased the dry matter intakQ16e, apparent digestibility of neutral detergent fiber, and ether extract, as well as the contents of acetic acid and propionic acid in rumen fluid. Moreover, EA supplementation regulated the ruminal microbiota, enhanced antioxidant capacity, and improved daily weight gain.

Effects of Dietary Calcium Lactate Supplementation on Laying Performance, Blood Index, Shinbone Quality, Jejunal Immunity, and Egg Quality of Aged Laying Hens

This study aimed to verify the potential of calcium lactate for the performance, blood index, shinbone quality, jejunal immunity, and egg quality of aged laying hens. A total of 360 62-week-old Hy-Line Brown laying hens were randomly divided into four treatments, with six replicates and 15 chickens per replicate. Experimental groups were fed with 0.25%, 0.5%, and 1.0% calcium lactate to substitute limestone in the control group (maintaining the same amount of calcium). The feeding trial lasted for 12 weeks. The laying rate and daily egg mass of laying hens fed the diets supplemented with calcium lactate was increased relative to those of the control group. The dietary addition of calcium lactate for laying hens enhanced the eggshell ratio, eggshell thickness, eggshell strength, and albumen height of eggs, and the addition level of 0.5% had the best effect. Dietary calcium lactate increased the number of red blood cells, corpuscular hemoglobin, mononuclear leucocytes and basophilic granulocytes, and decreased heterophils in the blood of laying hens. The activities of serum alanine transaminase and creatine kinase in laying hens was reduced by the dietary addition of calcium lactate. Calcium lactate supplementation in diets increased the serum calcium and phosphorus contents of laying hens. The dietary inclusion of calcium lactate increased the contents of IgA, IgG, lysozyme, and sIgA in the jejunal mucosa, and the 0.5% addition level worked best, but the IL-2 content decreased. The addition of 0.5% calcium lactate to the diet reduced the maximal force of the shinbone and increased the work required for shinbone rupture in laying hens. In conclusion, the dietary addition of calcium lactate improved the performance and egg quality of laying hens, probably by its positive effects on body health, intestinal digestible ability, calcium bioavailability, and jejunal mucosal immunity. The optimum amount of calcium lactate in the diet of laying hens is recommended to be 0.5%.

Effect of Guanidinoacetic Acid Supplementation on Growth Performance, Rumen Fermentation, Blood Indices, Nutrient Digestion, and Nitrogen Metabolism in Angus Steers

Guanidinoacetic acid (GAA) functions as a precursor for creatine synthesis in the animal body, and maintaining ample creatine reserves is essential for fostering rapid growth. This study aimed to explore the impact of GAA supplementation on growth performance, rumen fermentation, blood indices, nutrient digestion, and nitrogen metabolism in Angus steers through two experiments: a feeding experiment (Experiment 1) and a digestive metabolism experiment (Experiment 2). In Experiment 1, thirty-six Angus steers (485.64 ± 39.41 kg of BW) at 16 months of age were randomly assigned to three groups: control (CON), a conventional dose of GAA (CGAA, 0.8 g/kg), and a high dose of GAA (HGAA, 1.6 g/kg), each with twelve steers. The adaptation period lasted 14 days, and the test period was 130 days. Weighing occurred before morning feeding on days 0, 65, and 130, with rumen fluid and blood collected before morning feeding on day 130. Experiment 2 involved fifteen 18-month-old Angus steers (575.60 ± 7.78 kg of BW) randomly assigned to the same three groups as in Experiment 1, with a 7-day adaptation period and a 3-day test period. Fecal and urine samples were collected from all steers during this period. Results showed a significantly higher average daily gain (ADG) in the CGAA and HGAA groups compared to the CON group (p = 0.043). Additionally, the feed conversion efficiency (FCE) was significantly higher in the CGAA and HGAA groups than in the CON group (p = 0.018). The concentrations of acetate and the acetate:propionate ratio were significantly lower in the CGAA and HGAA groups, while propionate concentration was significantly higher (p &lt; 0.01). Serum concentration of urea (UREA), blood ammonia (BA), GAA, creatine, and catalase (CAT) in the CGAA and HGAA groups were significantly higher than in the CON group, whereas malondialdehyde (MDA) concentrations were significantly lower (p &lt; 0.05). Digestibility of dry matter (DM) and crude protein (CP) and the nitrogen retention ratio were significantly higher in the CGAA and HGAA groups than in the CON group (p &lt; 0.05). In conclusion, dietary addition of both 0.8 g/kg and 1.6 g/kg of GAA increased growth performance, regulated rumen fermentation and blood indices, and improved digestibility and nitrogen metabolism in Angus steers. However, higher doses of GAA did not demonstrate a linear stacking effect.

Salvia miltiorrhiza polysaccharide promotes the health of crayfish (Procambarus clarkii) by promoting hemocyte phagocytosis, protecting hepatopancreas and enhancing intestinal barrier function

Plant polysaccharides as immunomodulators are considered one of the effective measures to reduce antibiotic therapy in aquaculture. The immunomodulatory function of Salvia miltiorrhiza polysaccharides (SMP) has been demonstrated and begun to be applied in vertebrates, but its potential effect on crustaceans is unclear. In this study, crayfish (Procambarus clarkii) was fed with 0 %, 0.3 %, 0.7 %, 1.1 %, and 1.5 % SMP for 4 weeks to investigate the effects of SMP on hemocytes phagocytosis, hepatopancreatic function, and intestinal barrier function. The results revealed that hemocyte phagocytic activity was increased in all SMP groups. During the process of hemocytes phagocytic recognition and formation of phagosomes and phagolysosomes, the mRNA expression levels of mas, hem, rab3, ctsb, and lamp-1 were up-regulated mainly in the 0.3 % SMP group. During the clearance phase of phagocytosis, respiratory burst activity, ROS level, T-SOD, CAT, GST, and LZM activities were mainly increased in the 1.5 % SMP group. Hepatopancreas AKP and GOT activity were no significant change in all SMP groups. ACP activity was significantly enhanced in the 1.1 % SMP group. The GPT activity of 0.3–0.7 % SMP group was significantly decreased. The 0.7 % SMP group had the highest intestinal fold height. The highest index values of OTUs, Ace, Chao, and Shannon were in the 0.3 % SMP group. The dietary addition of 0.3 % SMP led to a tendency of increased relative abundance of Firmicutes and Bacteroidota at the phylum level, while the relative abundance of Proteobacteria at the phylum level decreased. In conclusion, dietary SMP could promote crayfish health by enhancing phagocytosis, protecting hepatopancreas and enhancing intestinal barrier function. This study contributes to the theoretical foundation for exploring the potential application of plant polysaccharides in crustaceans.

Dietary creatine promotes creatine reserves, protein deposition, and myofiber hyperplasia in muscle of juvenile largemouth bass (Micropterus salmoides)

Creatine can increase muscle mass, enhance performance, prevent disease-induced muscle atrophy, and improve overall cellular energy. This study investigated the effects of creatine as a feed additive on muscle growth and intrinsic molecular regulation mechanism in largemouth bass (Micropterus salmoides). Seven diets supplemented with different concentrations of creatine (0%, 0.1%, 0.25%, 0.5%, 1%, 2%, and 4%) were fed to juvenile largemouth bass (4.5–5.1 g) for eight weeks. Dietary creatine significantly increased body weight and body length, and reduced feed conversion ratio. High-performance liquid chromatography analysis revealed that dietary creatine addition notably increased creatine and phosphocreatine levels by 19.94% and 16.54% in the muscle of largemouth bass, respectively. Histological observation showed that dietary creatine significantly increased the total muscle fiber number and decreased the mean muscle fiber diameter. The Western blot results indicated that creatine ingestion significantly increased the protein level of MyoD1 in the muscle and promoted muscle fiber hyperplasia. In addition, dietary creatine also contributed to mTOR-S6K/4EBP1-mediated protein synthesis by maintaining AMPKα Thr172 dephosphorylation and AKT Thr308 phosphorylation. Moreover, the protein levels of the muscle-specific E3 ligases Atrogin1 and Murf1 responsible for ubiquitination degradation exhibited no significant change after feeding with creatine in largemouth bass. Overall, our data showed that creatine as a feed additive increased creatine and phosphocreatine contents, thus promoting muscle protein deposition and myofiber hyperplasia, eventually elevating growth performance and feed utilization efficiency in juvenile largemouth bass. The regression analysis of weight gain rate, specific growth rate, and feed conversion ratio determined 0.46%–0.54% creatine concentration range as optimal supplementation concentration for the culture of juvenile largemouth bass.

Tea polyphenols alleviate TBBPA-induced inflammation, ferroptosis and apoptosis via TLR4/NF-κB pathway in carp gills

The extensive application of Tetrabromobisphenol A (TBBPA) leads to the pollution of part of the water environment and brings great safety risks to aquatic animals. As a natural extract, tea polyphenols (TPs) have antioxidant and anti-inflammatory effects. Gills are one of the immune organs of fish and constitute the first line of defense of the immune system. However, it was unclear whether TPs could mitigate TBBPA-induced gills injury. Therefore, an animal model was established to investigate the effect of TPs on TBBPA-induced gills. The results indicated that TBBPA changed the coefficient and tissue morphology of carp gills. In addition, TBBPA induced oxidative stress and inflammation, leading to ferroptosis and apoptosis in carp gills. Dietary addition of TPs significantly improved the antioxidant capacity of carp, effectively inhibited the overexpression of TLR4/NF-κB and its mediated inflammatory response. Moreover, TPs restored iron metabolism, reduced the expression of pro-apoptotic factors thereby alleviating ferroptosis and apoptosis in carp gills. This study enriched the protective effect of TPs and provided a new way to improve the innate immunity of carp.

Leucine improves the growth performance, carcass traits, and lipid nutritional quality of pork in Shaziling pigs

Leucine is involved in promoting fatty acid oxidation and lipolysis, mediating lipid metabolism and energy homeostasis, thus it has been widely used in livestock production. However, the effects of leucine on fat deposition and nutrition in Shaziling pigs remain unclear. A total of 72 Shaziling pigs (150 days old, weight 35.00 ± 1.00 kg) were randomly divided into 2 groups and fed with basal diet (control group) or basal diet containing 1% leucine (leucine group) for 60 days. The results showed that leucine significantly increased the average daily feed intake but decreased the ratio of feed to gain (P < 0.05), increased the loin muscle area and serum glucose content (P < 0.05) of Shaziling pigs. Besides, leucine regulated the re-distribution of fatty acids from adipose tissue to muscle as it significantly increased the contents of C18:1n-9 and C22:6n-3 (DHA) in the longissimus thoracis while decreased the contents of C22:5n-3 (DPA), C20:5n-3 (EPA), and DHA in the adipose tissue of Shaziling pigs (P < 0.05). Lipidomic analysis showed that the contents of phosphatidylethanolamines (PEs), cardiolipins (CLs), and phosphatidylglycerols (PGs) in the longissimus thoracis and the contents of lysophosphatidylethanolamines (LPEs), ceramides (Cers), phosphatidylinositols (PIs) in adipose tissue of Shaziling pigs were decreased in leucine group (P < 0.05). Collectively, this study clarified that dietary addition of 1% leucine have a better effect on growth performance and the deposition of beneficial fatty acids in the muscle of Shaziling pigs, which is conductive to the production of high quality and healthy pork. In addition, leucine altered the lipid composition of muscle and fat in Shaziling pigs. The related results provide a theoretical basis and application guidance for regulating fat deposition in Shaziling pigs, which is important for the healthy breeding of Shaziling pigs.