Effect of in ovo injection of threonine on immunoglobulin A gene expression in the intestine of Japanese quail at hatch

Advanced chelate technology-based trace minerals reduce inflammation and oxidative stress in Eimeria-infected broilers by modulating NF-kB and Nrf2 pathways

This study investigated the effects of substituting inorganic trace minerals (ITM) with advanced chelate technology-based TM (ACTM) in broiler chicken feed on productive performance, metabolic profile, humoral immunity, antioxidant status, and modulation of NF-kB and Nrf2 signaling pathways in mixed Eimeria species exposure. The study involved 480 newly hatched male broiler chickens, which were divided into 5 treatment groups, each with 6 replicate cages and 16 chickens per replicate. The experimental treatments included an uninfected negative control group fed a basal diet with recommended inorganic TM levels (NC), an infected positive control group fed the same diet (PC), a PC group supplemented with salinomycin (SAL), and two PC groups in which the basal diet was replaced with 50% and 100% ACTM instead of inorganic TM (ACTM50 and ACTM100, respectively). All groups, except for the NC group, were orally challenged with mixed Eimeria species oocysts on day 14. According to the results, the PC group showed lower feed intake, breast yield, low-density lipoprotein-cholesterol concentration, lactobacillus spp. counts, and serum IgG levels, but higher jejunal TGF-β expression versus the NC group. The broilers in the NC, SAL, and ACTM100 groups showed higher body weight gain, carcass yield, and TGF-β expression, but lower serum alkaline phosphatase activity, ileal E. coli count, and jejunal expression levels of IL-1β, IL-6, IFN-γ, Nrf2, and SOD1 compared to the PC group, with the NC group having the highest body weight gain and lowest IL-1β and Nrf2 expression levels. Furthermore, the administration of ACTM100 treatment improved feed efficiency, increased serum iron, zinc, manganese, and copper levels, enhanced total antioxidant capacity and different antioxidant enzyme activities, and reduced malondialdehyde concentration. In conclusion, complete replacement of ITM with ACTM effectively protects broilers from Eimeria infection, with similar positive effects to SAL treatment in terms of productive performance and anti-inflammatory responses and better antioxidant responses and mineral availability.

Potential benefits of advanced chelate-based trace minerals in improving bone mineralization, antioxidant status, immunity, and gene expression modulation in heat-stressed broilers

Organic sources of trace minerals (TM) in broiler diets are more bioavailable and stable than inorganic sources, making them particularly beneficial during challenging periods such as heat stress (HS) conditions. A 42-d study investigated the effects of using advanced chelate technology-based TM (ACTM) or adding varying amounts of ACTM to broiler diets during HS conditions. The study involved 672 male broiler chickens in 7 treatment groups, including a thermoneutral control (TNC) group and six HS treatments. There were 8 replicate pens per treatment and 12 birds per replicate. The six HS treatments included birds exposed to a cyclic HS environment (34°C) for 8 h and were as follows: HSC, which consisted of the same basal diet with the recommended ITM levels; ACTM50 and ACTM100, which replaced the basal diet with 50% and 100% ACTM instead of ITM; ITM+ACTM12.5 and ITM+ACTM25, which involved adding extra ACTM to the ITM basal diet at 12.5% and 25%, respectively; and ITM125, which used 125% of the recommended levels of ITM in the basal diet. Compared with the HSC treatment, the TNC, ACTM100, and ITM+ACTM25 treatments resulted in increased (P < 0.05) body weight; tibia weight; tibia ash, phosphorus, iron, and manganese contents; secondary antibody titers; and serum TAC and SOD values but decreased (P < 0.05) serum MDA concentrations and the expression levels of the hepatic genes IL-1β, IL-6, and INF-γ. The TNC and ACTM100 groups also showed greater (P < 0.05) feed efficiency, tibia length, tibia zinc content, and hepatic SOD1 expression but exhibited reduced (P < 0.05) hepatic NF-kB expression. Significant increases (P < 0.05) in primary anti-NDV titers, serum GPx1 activity, and Nrf2 and GPx1 gene expression levels were also detected in the ACTM100, ITM+ACTM12.5, and ITM+ACTM25 groups. In conclusion, the findings suggest that replacing ITM with ACTM or adding ACTM to ITM diets, especially at a 25% higher dose, can effectively protect broilers from heat stress by promoting growth, reducing inflammation, and increasing the expression of antioxidant proteins.

Dietary advanced chelate technology-based 7-mineral supplement improves growth performance and intestinal health indicators during a mixed Eimeria challenge in broiler chickens

The health and productivity of broilers may be improved by optimizing the availability and levels of trace minerals (TM) in their feed, especially in the presence of parasites. This study investigated the effects of replacing inorganic TM (ITM) with an advanced chelate technology-based 7 TM (ACTM) on performance, hematology, lesion score, oocyst shedding, gut morphology, and tight junction structure in broilers challenged with mixed Eimeria species. There were 480 1-day-old broiler chickens divided into 5 groups: uninfected negative control and recommended levels of ITM (NC); infected positive control and recommended levels of ITM (PC); or PC supplemented with salinomycin (SAL); PC diet with 50 % ACTM instead of ITM (ACTM50); or PC diet with 100 % ACTM instead of ITM (ACTM100). All groups, except NC, were orally challenged with mixed Eimeria spp. oocysts on day 14. Each group had 6 replicate cages, with 16 birds per replicate. The results showed that the NC, SAL, and ACTM100 groups had higher (P < 0.05) body weight, average daily gain (ADG), and European production efficiency index (EPEI), as well as a lower (P < 0.05) feed conversion, mortality rate, and heterophile to lymphocyte ratio compared to the PC group, with the NC group having the highest ADG and EPEI throughout the experiment. The SAL and ACTM100 groups had lower (P < 0.05) intestinal lesion scores and oocyst numbers compared to the PC group, although all coccidiosis-challenged groups had higher oocyst shedding compared to the NC group. On day 24, the challenged birds in the SAL and ACTM100 groups had higher (P < 0.05) villus height and surface area in the duodenum and ileum, as well as a higher (P < 0.05) villus height to crypt depth ratio in the jejunum. The expression levels of jejunal CLDN1 and ZO-1 were also higher (P < 0.05) in the ACTM100 and SAL groups compared to the PC and ACTM50 groups at 24 days of age. In conclusion, while using ACTM in broiler diets at 50 % of the commercial recommended levels maintained performance and physiological responses, complete replacement with ACTM improved growth performance and intestinal health characteristics, similar to salinomycin under Eimeria challenge conditions.

Physiological effects of in ovo delivery of bioactive substances in broiler chickens

The poultry industry has improved genetics, nutrition, and management practices, resulting in fast-growing chickens; however, disturbances during embryonic development may affect the entire production cycle and cause irreversible losses to broiler chicken producers. The most crucial time in the chicks' development appears to be the perinatal period, which encompasses the last few days of pre-hatch and the first few days of post-hatch. During this critical period, intestinal development occurs rapidly, and the chicks undergo a metabolic and physiological shift from the utilization of egg nutrients to exogenous feed. However, the nutrient reserve of the egg yolk may not be enough to sustain the late stage of embryonic development and provide energy for the hatching process. In addition, modern hatchery practices cause a delay in access to feed immediately post-hatch, and this can potentially affect the intestinal microbiome, health, development, and growth of the chickens. Development of the in ovo technology allowing for the delivery of bioactive substances into chicken embryos during their development represents a way to accommodate the perinatal period, late embryo development, and post-hatch growth. Many bioactive substances have been delivered through the in ovo technology, including carbohydrates, amino acids, hormones, prebiotics, probiotics and synbiotics, antibodies, immunostimulants, minerals, and microorganisms with a variety of physiological effects. In this review, we focused on the physiological effects of the in ovo delivery of these substances, including their effects on embryo development, gastrointestinal tract function and health, nutrient digestion, immune system development and function, bone development, overall growth performance, muscle development and meat quality, gastrointestinal tract microbiota development, heat stress response, pathogens exclusion, and birds metabolism, as well as transcriptome and proteome. We believe that this method is widely underestimated and underused by the poultry industry.

Effects of cLFchimera peptide on intestinal morphology, integrity, microbiota, and immune cells in broiler chickens challenged with necrotic enteritis

Three hundred and sixty 1-day-old male broiler chicks were randomly allocated to 4 treatments of 6 replicates to evaluate the effects of cLFchimera, a recombinant antimicrobial peptide (AMP), on gut health attributes of broiler chickens under necrotic enteritis (NE) challenge. Treatments were as follows: (T1) unchallenged group fed with corn-soybean meal (CSM) without NE challenge and additives (NC); (T2) group fed with CSM and challenged with NE without any additives (PC); (T3) PC group supplemented with 20 mg cLFchimera/kg diet (AMP); (T4) PC group supplemented with 45 mg antibiotic (bacitracin methylene disalicylate)/kg diet (antibiotic). Birds were sampled for villi morphology, ileal microbiota, and jejunal gene expression of cytokines, tight junctions proteins, and mucin. Results showed that AMP ameliorated NE-related intestinal lesions, reduced mortality, and rehabilitated jejunal villi morphology in NE challenged birds. While the antibiotic non-selectively reduced the count of bacteria, AMP restored microflora balance in the ileum of challenged birds. cLFchimera regulated the expression of cytokines, junctional proteins, and mucin transcripts in the jejunum of NE challenged birds. In conclusion, cLFchimera can be a reliable candidate to substitute growth promoter antibiotics, while more research is required to unveil the exact mode of action of this synthetic peptide.

Antimicrobial peptide, cLF36, affects performance and intestinal morphology, microflora, junctional proteins, and immune cells in broilers challenged with E. coli

This study investigated the effects of an antimicrobial peptide (AMP), cLF36, on growth performance and the histophysiological changes of the intestine in E. coli-challenged broiler chickens. A total number of 360 day old male chicks were randomly assigned to 4 groups of 6 replicates as follows: T1) negative control diet based on corn-soybean meal without E. coli challenge and additives; T2) positive control diet based on corn-soybean meal and challenged with E. coli without any additives; T3) positive control diet challenged with E. coli and supplemented with 20 mg AMP (cLF36)/kg diet; T4) positive control diet challenged with E. coli and supplemented with 45 mg antibiotic (bacitracin methylene disalicylate)/kg diet. Results showed that T3 improved growth performance and the jejunal morphology of E. coli-challenged chickens similar to those of T4. While antibiotic non-selectively decreased the population of ileal bacteria, AMP increased the population of Lactobacillus spp. and decreased harmful bacteria in the ileum of E. coli-challenged chickens. Supplementing E. coli-challenged chickens with AMP improved the gene expression of immune cells and upregulated the expression of tight junction proteins compared to other challenged groups. In conclusion, although cLF36 beneficially affected growth performance and the intestinal morphology of E. coli-challenged chickens similar to those of the antibiotic group, this AMP drastically improved the intestinal microbiome, immune cells, and junctional proteins compared to other E. coli-challenged birds, and can be nominated as an alternative for growth promoter antibiotics.

In ovo delivery of various biological supplements, vaccines and drugs in poultry: current knowledge

The technique of delivering various nutrients, supplements, immunostimulants, vaccines, and drugs via the in ovo route is gaining wide attention among researchers worldwide for boosting production performance, immunity and safeguarding the health of poultry. It involves direct administration of the nutrients and biologics into poultry eggs during the incubation period and before the chicks hatch out. In ovo delivery of nutrients has been found to be more effective than post-hatch administration in poultry production. The supplementation of feed additives, nutrients, hormones, probiotics, prebiotics, or their combination via in ovo techniques has shown diverse advantages for poultry products, such as improved growth performance and feed conversion efficiency, optimum development of the gastrointestinal tract, enhancing carcass yield, decreased embryo mortality, and enhanced immunity of poultry. In ovo delivery of vaccination has yielded a better response against various poultry pathogens than vaccination after hatch. So, this review has aimed to provide an insight on in ovo technology and its potential applications in poultry production to deliver different nutrients, supplements, beneficial microbes, vaccines, and drugs directly into the developing embryo to achieve an improvement in post-hatch growth, immunity, and health of poultry. © 2019 Society of Chemical Industry.

Effects of dietary threonine and immune stress on growth performance, carcass trait, serum immune parameters, and intestinal muc2 and NF-κb gene expression in Pekin ducks from hatch to 21 days

An experiment was conducted to investigate the effects of different dietary threonine (Thr) levels and immune stress on Pekin ducklings' growth performance, carcass traits, serum immune parameters, and intestinal mucin 2 (MUC2) and nuclear factor kB (NF-κB) gene expressions. A total of 320 Pekin ducklings was randomly assigned to a 5 × 2 factorial arrangement of treatments. Each treatment group consisted of 4 replicate pens with 8 ducks per pen. Ducklings were fed 5 graded levels of Thr: 0.49, 0.56, 0.60, 0.65, and 0.76% from hatch to 21 d of age. At 11 d of age, ducks in the stressed groups were challenged with bovine serum albumin (BSA), and ducks in the unstressed groups were injected with normal saline water. The results showed that increasing Thr supplementation from 0.49 to 0.56% in the diet can improve BWG; feed consumption; weight and relative weight of breast and leg; weight of liver, bursa of Fabricius, spleen, and thymus; serum natural immune globulin A (IgA) concentration; and MUC2 gene expression in the ileum of 21-day-old Pekin ducks, significantly (P < 0.05). Immune stress with BSA had a significant effect on 21-day-old Pekin ducklings' BWG, feed consumption, and weight and relative weight of breast and thymus (P < 0.05), but no interaction between BSA and dietary Thr content was noticed in our experiment in 21-day-old Pekin ducks (P < 0.05). Dietary Thr requirements of the unstressed groups and stressed groups based on broken-line model analyses for ducks' BWG were 0.705 and 0.603%, respectively, and for ducks' feed consumption were 0.724 and 0.705%, respectively.

Effects of deficiency and surplus dietary threonine on reproductive performance of primiparous pregnant gilts

Dietary threonine imbalance is known to impair reproductive performances of gestating sows, but the underlying mechanisms are largely unknown. In this study, effects of deficiency and surplus dietary threonine during gestation on reproductive performance, serum metabolites and hormones concentration, and colostral nutrient and immunoglobulin contents of primiparous sows were investigated. Ninety primiparous pregnant gilts were assigned to one of the three dietary treatments with different standardized ileal digestible threonine/lysine ratios at 0.59, 0.72 and 0.85, which represented deficient (DT), adequate (AT) and surplus (ST) dietary threonine concentration respectively. Maternal body weight gain from day 80-110 of gestation was highest (p < .05) for gilts fed AT than for gilts fed DT or ST. On days 30 and 110, serum threonine concentration increases in a dose-dependent manner with the increasing of dietary threonine concentration in (p < .01), serum urea nitrogen concentration was lower (p < .01) in gilts fed AT than DT or ST, and serum insulin-like growth factor-I (IGF-I) was lowest (p < .05) for gilts fed DT. On day 110, gilts fed AT had lower serum progesterone concentration but higher concentrations of serum prolactin (p < .05) compared to DT and ST. Concentration of colostral immunoglobulin A and G from gilts fed DT was lower (p < .05) compared with gilts fed AT or ST. In conclusion, gilts with the adequate threonine intake were more able to conserve dietary amino acids to support foetal and maternal tissue gain. Deficient or ST threonine intake may induce a delay in changes in progesterone and prolactin concentrations during the prepartum period impeding the transition from pregnancy to lactation.