Effects of supplemental chromium on interferon-gamma (IFN-gamma) mRNA expression in response to Newcastle disease vaccine in broiler chicken

Effects of Supplemental Chromium Nanoparticles on IFN-γ expression of Heat Stress Broilers

The aim of present study was to investigate the beneficial effect of chromium (III) picolinate (CrPic) and chromium (III) picolinate nanoparticles (NCrPic) addition on growth performance, stress-related hormonal changes, and serum levels of various immunity biomarkers, as well as the gene expression of IFN-γ in broilers exposed to heat stress conditions. Treatments included T1 which received the basal diet with no feed additive; T2 exposed to heat stress; T3, T4, and T5 containing 500, 1000, and 1500 ppb CrPic; as well as T6, T7, and T8 containing 500, 1000, and 1500 ppb NCrPic, respectively. After 2 weeks from CrPic and NCrPic supplementation, IFN-γ mRNA expression was assayed using the RT-PCR technique. The results showed that the lower body weight, daily weight gain, daily feed intake by heat stress, and the feed conversion ratio were recovered remarkably by CrPic and NCrPic supplements. The stress-elevated levels of cortisol and immunoglobulin were reduced significantly using CrPic and NCrPic supplementation (P ≤ 0.05). The gene expression profile showed that the upregulated expression of IFN-γ was regulated by the addition of CrPic and NCrPic, in particular, to the diet; however, a full downregulation of IFN-γ expression was observed after week 2 of NCrPic supplementation. In conclusion, the results indicated that nanoparticle supplementation could be effective in reducing heat stress-induced detrimental alterations, thereby attributing to substantial changes to the immune system, including IFN-γ expression.

Effects of different sources and levels of dietary chromium supplementation on performance of broiler chicks

The current experiment was carried out to evaluate the effect of different dietary chromium supplementation sources, chromium oxide (Cr₂ O₃ ), chromium methionine (Cr-Met), or chromium yeast (Cr-yeast), at different levels each (500 or 1,000 ppb) on growth performance, physiological traits, and carcass characteristics of broiler chicks. A total of 490 seven-day-old Arbor Acres chicks were randomly distributed into 7 experimental groups each in 10 replicates of 7 birds each. The groups were control, 500 ppb Cr₂ O₃ , 1,000 ppb Cr₂ O₃ , 500 ppb Cr-Met, 1,000 ppb Cr-Met, 500 ppb Cr-yeast, and 1,000 ppb Cr-yeast. The results showed significant superiority of the organic chromium sources (Cr-Met or Cr-yeast) concerning body weight and weight gain, the group supplemented with 1,000 ppb Cr-yeast consumed the lowest feed (3,185 g) and had the best feed conversion ratio (1.60) compared to the control (1.73). The chromium treatments recorded significantly better protein and lipid profile, antioxidant status, and immunological parameters than the control group. Similarly, dietary chromium supplementation increased carcass yield and decreased intestinal pathogenic bacteria. In conclusion, supplementing broiler diets with organic chromium sources at 1,000 ppb promotes growth performance, physiological traits, and carcass characteristics; such chromium treatments enhanced the antioxidant status and immunity levels of broilers.

Effect of Varying Levels of Chromium Propionate on Growth Performance and Blood Biochemistry of Broilers

Simple Summary

The current study evaluated the effects of dietary chromium propionate supplementation on growth performance and blood biochemistry of broilers. Results showed that chromium propionate has improved weight gain and feed conversion ratio (FCR) of broilers. Also, meat to fat ratio improved and lean meat may be produced. Based on the study results, the recommended level of chromium propionate supplementation to broiler diet for better performance and weight gain is 400 ppb.

Abstract

The objective of this work was to evaluate the effects of varying levels of chromium propionate on blood biochemistry and growth performance of broilers (1–35 days). Five diets were formulated by using chromium propionate with inclusion levels of 0, 200, 400, 800 and 1600 ppb. A total of 300 broilers were divided into 5 groups with 6 replicates of 10 birds in each under completely randomized design. The starter feed intake remained unaffected (p > 0.05) whereas finisher and overall feed intake was different (p < 0.05) among different experimental groups. Feed conversion ratio and weight gain in starter, finisher and overall improved significantly (p < 0.05) with the increasing levels of chromium propionate. Blood glucose was decreased (p < 0.05) with increasing dietary chromium level. Chromium supplementation did not affect antibodies titers against NDV and AIV-H9. Neither live, hilal, after skin removal, eviscerated, chest weight and legs with shanks weight nor liver and heart weights were affected (p > 0.05) while gizzard weight reduced significantly (p < 0.05) due to supplementation of chromium. On the basis of results, it may be concluded that chromium propionate supplementation improved weight gain and FCR and reduced blood glucose. However, better performance and weight gain may be achieved if chromium propionate is added at the rate of 400 ppb in broiler diets.

A bacterial ghost improves the immunological efficacy of a Newcastle disease virus inactivated vaccine

Newcastle disease (ND) is one of the most common contagious viral infectious diseases of poultry. Vaccination is an effective way to protect chickens from Newcastle disease virus (NDV), and large efforts have been made to acquire not only new vaccines but also new adjuvants to improve the efficiency of existing inactivated vaccines. Here, we observed the adjuvanticity of the bacterial ghost (BG) on the effectiveness of inactivated NDV vaccine in a chicken model. We found that BG, as an adjuvant with inactivated NDV vaccine, substantially strengthened the ND-specific antibody response and protection against lethal challenge in a chicken model, reduced viral shedding, strengthened the time duration of antibody titers, produced an available immunization effect with a low dose of vaccine, and improved serum IL-2 and IFN-γ concentrations. Our results demonstrate that BG significantly improved the immunogenicity of an inactivated NDV vaccine and is a new immune adjuvant candidate.

Recent advances in role of chromium and its antioxidant combinations in poultry nutrition: A review

Poultry is reared in open side houses in most of the tropical countries, which results in huge temperature variation in shed causing stress resulting in increased demand of antioxidant supplementation. Since cooling of poultry houses or environment control is very expensive, thus methods focused on nutritional modifications appears to be the much logical approach. Stress increases mineral and vitamin mobilization from tissues and their excretion. Effect of some minerals and vitamin supplements such as chromium (Cr) and ascorbic acid to elevate the negative effects of environmental stress is well documented. Cr functions as an antioxidant and its deficiency are said to disrupt carbohydrate and protein metabolism. Cr has been utilized for weight gain, to improve feed conversion ratio, increase relative organ weight, muscle development, decrease cholesterol, increase high-density lipoprotein cholesterol, and improve nutrient digestion. Therefore, the present review discusses the beneficial aspects of Cr with its effect in different doses and antioxidant combinations to explore and promote its optimum utilization in poultry nutrition and production.

Effects of chromium methionine supplementation on growth performance, serum metabolites, endocrine parameters, antioxidant status, and immune traits in growing pigs

The effects of dietary chromium methionine (CrMet) on growth performance, serum metabolites, endocrine parameters, antioxidant status, and immune traits in growing pigs were investigated. A total of 180 crossbred pigs (30.18 ± 0.28 kg initial body mass) were randomly divided into five groups, each group with six pens, six pigs per pen. Pigs were fed on the same basal diet supplemented with 0 (control), 100, 200, 400, and 800 μg/kg Cr from CrMet for 35 days. The results showed that supplemental CrMet did not affect growth performance. Cr at 200-800 μg/kg significantly decreased serum glucose levels (P < 0.05), while other serum metabolites were unaffected by Cr supplementation. Serum growth hormone (GH) levels were significantly decreased by Cr addition (P < 0.05). Furthermore, serum insulin-like growth factor I (IGF-I) levels were linearly decreased with increased Cr dose, and a significant reduction was observed in pigs fed 800 μg/kg Cr diets (P < 0.05). Serum immunoglobulin A, G, and M concentrations were increased linearly with increased Cr dosage, and pigs fed 400 μg/kg Cr had greater serum immunoglobulin M contents (P < 0.05). Cr at 400 μg/kg significantly increased serum superoxide dismutase and total antioxidant capacity activities (T-AOC) (P < 0.05). However, Cr at 800 μg/kg increased serum catalase activities, while decreasing serum T-AOC contents (P < 0.05). Additionally, there was a significant increase in serum malondialdehyde levels for pigs fed 800 μg/kg Cr diets (P < 0.05). These results indicated that dietary supplementation CrMet decreased serum glucose, GH, and IGF-I levels. Besides, supplemental 400 μg/kg Cr as CrMet improved serum antioxidant status and immune responses, but additional 800 μg/kg Cr resulted in lipid peroxidation in growing pigs.

Influence of chromium propionate on the carcass characteristics and immune response of commercial broiler birds under normal rearing conditions

The study investigated the effect of supplementation of chromium propionate at different dosage levels (100 to 3,200 µg/kg of elemental chromium in feed) on the performance, carcass characteristics, and immune response of broiler birds. The study was conducted on male broiler chickens (Cobb 400) for a period of 42 d as per the completely randomized design. Seven hundred 1-d-old birds were randomly segregated into 7 treatment groups, each with 10 replicates, and each replicate having 10 birds. Weight gain, feed intake, carcass characteristics, immune response, and the serum biochemical parameters of birds were studied during the supplementation period. There was no significant response to chromium supplementation on weight gain, feed intake, FCR, and lymphoid organ weights for the overall study period of 42 d. With increased chromium dosage, the breast meat yield improved linearly (P = 0.045). Antibody response to Newcastle disease vaccination improved quadratically (P = 0.001) with increased dose of chromium in the diet. Improved cell-mediated immune response was indicated by the increase (quadratic, P = 0.00) in lymphocyte proliferation ratio with increased dose of chromium supplementation. Heterophil:lymphocyte ratio decreased (quadratic, P = 0.004) with chromium propionate dosage, suggestive of reduced stress levels. Chromium propionate supplementation also reduced serum glucose levels (quadratic, P = 0.008) and improved (quadratic, P = 0.016) the total protein levels.

Effect of dietary supplementation of organic chromium on performance, carcass traits, oxidative parameters, and immune responses in commercial broiler chickens

An experiment was conducted to study effect of supplementing graded concentrations (0, 100, 200, 300, or 400 μg/kg diet) of organic chromium (Cr) on performance, carcass traits, oxidative stress, and immune responses in commercial broiler chickens reared in open-sided poultry house under tropical climatic conditions. Each diet was fed ad libitum to eight replicates consisting of six birds in each pen from 1 to 42 days of age. Body mass gain and feed efficiency at 21 and 42 days of age and relative mass of liver, abdominal fat, and ready to cook yields at 42 days of age were not affected (P > 0.05) by supplementing organic Cr in broiler diet. Body mass loss during pre-slaughter holding period (12 h) reduced and relative breast mass increased nonlinearly (P < 0.01) with concentration of Cr in diet. Lipid peroxidation decreased, while activities of glutathione peroxidase and glutathione reductase in plasma increased nonlinearly with Cr supplementation. The ratio between heterophyl and lymphocyte was not affected (P > 0.05) with Cr supplementation in broiler diet. Relative mass of lymphoid organs (bursa, spleen, and thymus) and antibody production to Newcastle disease vaccination were not affected (P > 0.05) by the treatments employed. The cell-mediated immunity (lymphocyte proliferation ratio) increased nonlinearly with dietary Cr concentration. The results of the present study indicated that supplementation of organic Cr did not influence body mass and feed efficiency. However, supplementation of the Cr reduced pre-slaughter holding losses, increased the relative mass of breast, and increased antioxidant status and lymphocyte proliferation in broilers reared in tropics.

Abundance of IFN-α and IFN-γ gene transcripts and absence of IL-2 transcripts in the blood of chickens vaccinated with live or inactivated NDV

As immune responses to live and inactivated vaccines might differ, temporal responses of broiler chickens to vaccination were examined on the basis of the abundance in the circulating blood of gene transcripts of IFN-α, IFN-γ and IL-2, critical cytokines for immune responses. Blood samples were collected 6, 12 and 24 hours, and 7 and 14 days following vaccination with either live or inactivated Newcastle disease virus, La Sota strain, at 14 days of age, and the abundance of transcripts for each cytokine was assayed by real-time RT-PCR. Physiological saline and vaccine emulsion without viral antigen were administered to control groups for live and inactivated vaccine groups, respectively. The abundance of IFN-γ transcripts was elevated during the early times following vaccination and had reached baseline by the seventh day but the abundance of IFN-α transcripts remained elevated. Transcripts for neither IFN gene were detected in the control birds. The abundance of transcripts for each IFN was not different between the two vaccinated groups at any time. Transcripts for IL-2 were detected only in spleens from chicken embryos that had been inoculated with the live virus. The results show that cells stimulated to produce IFN-α and IFN-γ enter the circulating blood but those stimulated to produce IL-2 do not, or in very low number, and the IFN responses to both vaccines are the same.

DNA-chitosan nanoparticles improve DNA vaccine-elicited immunity against Newcastle disease virus through shuttling chicken interleukin-2 gene

In this study, pCAGG-ChIL2 plasmid DNA containing the chicken interleukin-2 (ChIL-2) gene was used to prepare DNA-chitosan nanoparticles (CNPs). The CNPs prepared were spherical, with mean diameters between 100 and 200 nm, have a positive surface charge, and could protect DNA against DNase I degradation. The CNPs prepared were successfully used to transfect the Df-1 cell line with almost no cytotoxicity. CNPs prepared at an amino group to phosphate group ratio (N/P ratio) of 16 provided the highest transfection efficiency (1.1%) in medium with a pH of 6.5. When pCAGG-ChIL2 CNPs were administered to chickens simultaneously with a DNA vaccine against Newcastle disease virus (NDV), haemagglutination inhibition antibody titers and serum interferon-γ (IFN-γ) levels were significantly higher than in chickens immunised with the NDV DNA vaccine alone (p < 0.05). The results demonstrate that pCAGG-ChIL2 CNPs improve DNA vaccine-elicited immunity against NDV challenge.