Production of Intestinal Mucins, sIgA, and Metallothionein after Administration of Zinc and Infection of Ascaridia galli in Chickens: Preliminary Data

Dietary Dihydromyricetin Zinc Chelate Supplementation Improves the Intestinal Health of Magang Geese

To fulfill the nutritional requirements of poultry, effective Zn supplementation is required due to Zn deficiency in basic feed. In this study, we investigated the effects of DMY-Zn (dihydromyricetin zinc chelate) on the growth performance, morphology, and biochemical indices; the expression of intestinal barrier-related genes; the intestinal microflora; and the cecum metabolome of Magang geese. A total of 300 14-day-old Magang geese (equal number of males and females) with an average body weight of 0.82 ± 0.08 kg were randomly divided into five groups and fed a basal diet; these groups were given DMY-Zn (low, medium, or high level of DMY-Zn with 30, 55, or 80 mg/kg Zn added to the basal diet) or ZnSO4 (80 mg/kg Zn added) for 4 weeks. Our results revealed that DMY-Zn significantly impacts growth and biochemical indices and plays a significant role in regulating the intestinal barrier and microflora. DMY-Zn is involved in the upregulation of intestinal barrier gene (ZO1 and MUC2) expression, as well as upregulated Zn-related gene expression (ZIP5). On the other hand, a low concentration of DMY-Zn increased the ɑ diversity index and the abundance of Lactobacillus and Faecalibacterium. Additionally, a cecal metabolomics study showed that the main metabolic pathways affected by DMY-Zn were the pentose phosphate pathway, the biosynthesis of different alkaloids, and the metabolism of sphingolipids. In conclusion, DMY-Zn can reduce feed intake, increase the expression of intestinal barrier-related genes, help maintain the intestinal microflora balance, and increase the abundance of beneficial bacteria in the intestine to improve intestinal immunity.

Ascaridia galli infection in chicken: Pathobiology and immunological orchestra

BACKGROUND

Ascaridia galli is the largest gut-dwelling helminth of chickens, which confers adverse effects on meat and egg production; thus, on the animal protein supply and the economy. Both adult and immature parasites affect gut health, but larval stages play a major role in pathology.

AIMS

Here, we present immunology and pathology of A. galli in chickens.

MATERIALS AND METHODS

Literatures were surveyed through online platforms such as PubMed, Google Scholar and Researchgate.

RESULTS

The larvae cause excessive mucus production, damage to the intestinal gland, hemorrhage, anemia, diarrhea, and malnutrition. The adult worms can cause death by intestinal obstruction and intussusception. Although both cellular and humoral immunity are involved in fighting against ascariasis, the role of naturally acquired immunity is poorly defined. In cellular immunity, Th-2 cytokines (IL-4, IL-5, IL-9, and IL-13), goblet cells (mucin), gut-associated lymphoid tissues, CD8α+ intraepithelial cells, TCRγδ + T cells, and TGF-β4 form a protective band. Type 2 immunity provides protection by forming a network of endogenous damage-associated molecular patterns, chitin, and parasitic antigens. Among antibodies, IgY is the most prominent in chickens and provides temporary humoral protection. During parasitic infection, infiltration of various immune cells is evident, especially in the intestinal epithelium, lamina propria, and crypts of the duodenum and jejunum. In chickens older than 12 weeks, gradual reduction of worm burden is more successful than the younger birds. Female chickens exert a short-lived but higher level of protection by passing IgY to chicks in the form of egg yolk antibodies. In laying conditions, immunity differs between breeds. This review provides an overview of the silent but inevitable pathological changes induced by A. galli and the interaction of host immunity with the parasite.

Integrated evaluation of the requirements and excretions of Cu, Fe, Zn, and Mn for broilers via a uniform design method

This study aimed to determine the ideal balance profile of Cu, Fe, Zn, and Mn for broilers of 1-21 days of age via a uniform experimental design. In Experiment 1, 900 1-day-old Arbor Acres male broilers were randomly allotted to 15 dietary treatments with six replicates of 10 birds. A total of 14 experimental diets were formulated with the supplementation of 8~16, 123~160, 40~80, and 60~120 mg/kg of Cu, Fe, Zn, and Mn, respectively, in the basal diet, according to the uniform design method. The excretion of Cu, Fe, Zn, and Mn in the manure and the broiler performance were determined to build the ideal balance profile of these elements. Experiment 2 was conducted based on the ideal balance profile built in Experiment 1, to test its practicability using 720 broilers with two treatments. The dietary concentrations of Cu, Fe, Zn, and Mn in the control group were 15.19, 203.08, 76.78, and 86.13 mg/kg, respectively. In Experiment 1, the concentrations of Cu, Fe, Zn, and Mn in the diets were 16.96, 166.66, 46.01, and 60.26 mg/kg, respectively, when the average daily gain reached the optimum value. When the dietary concentrations of Cu, Fe, Zn, and Mn were 8.54, 130.66, 38.19, and 64.07 mg/kg, respectively, the total excretion of Cu, Fe, Zn, and Mn got the minimum value. There are corresponding ideal balance profiles for minimum excretion of a certain element. In Experiment 2, the dietary levels of Fe, Zn, and Mn were decreased by 17.93%, 40.08%, and 30.04%, respectively, which had no significant effect on average daily gain, average daily feed intake, and feed gain for 1~21 day-old broilers but markedly decreased the excretion of Cu and Mn and total excretion. It was concluded that there is a dilemma between growth performance and mineral excretion. Although dietary levels of Cu, Fe, Zn, and Mn supporting optimal growth are higher than those for minimizing mineral excretion, supplementing too many trace elements in the diets of broilers is unnecessary.