A total of 360-day-old broiler chicks were allocated into six groups in 2 (Coccidial challenge or not) × 3 (dietary treatments) factorial design. Three dietary treatments including: basic diet, basic diet plus organic acids (OAs) in drinking water, and basic diet plus OAs in the feed with and without coccidial challenge. The OAs in water or feed improved (P < 0.01) average body weight (ABW), average body weight gain (ABWG), and feed conversion ratio (FCR) as compared with the control diet during starter, grower, and whole experimental period. Coccidial challenge decreased BW, ABWG, and average feed intake (AFI), as well as resulted in poor FCR during the starter and whole experimental period (P < 0.05). Though there was no interaction between OAs supplementation and coccidial challenge, the OAs supplementation improved the overall performance with and without coccidial challenge birds on 21 d and 35 d. IgG was found higher (P = 0.03) in broilers fed OAs in feed without the coccidial challenge group. On 18 d, OAs supplementation in feed increased TNF-γ (P = 0.006), whereas the coccidial challenge decreases TNF-γ (P = 0.01) and IL-10 (P = < .0001), and increases IgM (P = 0.03), IgG (P = 0.04) and IgA (P = 0.02). On 29 d, the coccidial challenge increases IgM and IgA. On 18 d, jejunal lesion score was found significantly higher in the coccidial challenged group as compared to OAs supplementation with coccidial challenged groups on 18 d (P < 0.0001) and 29 d (P = 0.03). Crypt depth was higher, and Villus-height to Crypt depth ratio was lower in the coccidial challenge group on 18 and 29 d. The Goblet cells were found higher in the non-coccidial challenge on 18 d. After 18 d, 16S rDNA gene sequence analysis of ileal chyme has shown that coccidial challenge decreases Lactobacillus_reuteri species as compared to the non-challenged group (P = 0.02). After 29, Cyanobacteria abundance reduced (P = 0.014) in the challenged group than the non-challenged group at the phylum level. At the genus level, Lactobacillus (P = 0.036) and unidentified Cyanobacteria (P = 0.01) were found higher in the non-challenged group than the coccidial challenge group. The results indicate that the OAs supplementation showed improved responses in a pattern similar to the non-challenged control group by neutralizing the negative effects of the coccidial challenge.

Metals are widely used in animal feed for their growth-stimulating and antimicrobial effects, yet their use may potentially promote the proliferation of antibiotic resistance through co-selection. We studied the prevalence and associations of metal, antibiotic, and disinfectant resistances of 300 Salmonella Typhimurium isolates from pig meat, pig manure, chicken meat, poultry manure, and human stool from Sichuan, China. Seventy four percent of the 300 Salmonella Typhimurium isolates were considered resistant to Cu, almost 50% to Zn and Cr, over 25% to Mn and Cd, and almost 10% to Co. Most of the isolates carried at least one heavy metal resistance gene (HMRG). The Cr-Zn-Cd-resistance gene czcD was carried by 254 isolates and the Cu-resistance genes pcoR and pcoC by 196 and 179 isolates, respectively. Most of the isolates were resistant to at least one antibiotic and almost 80% were multidrug-resistant. The prevalence of resistance to six antibiotics was higher among the pig meat and manure isolates than among other isolates, and that of streptomycin and ampicillin were highest among the pig meat isolates and that of ciprofloxacin and ofloxacin among the pig manure isolates. From 55 to 79% of the isolates were considered resistant to disinfectants triclosan, trichloroisocyanuric acid, or benzalkonium chloride. The metal resistances and HMRGs were associated with resistance to antibiotics and disinfectants. Especially, Cu-resistance genes were associated with resistance to several antibiotics and disinfectants. The transfer of the Cr-Zn-Cd-resistance gene czcD, Cu-resistance gene pcoC, and Co-Ni-resistance gene cnrA into Escherichia coli and the increased Cu-resistance of the transconjugants implied that the resistance genes were located on conjugative plasmids. Thus, the excessive use of metals and disinfectants as feed additives and in animal care may have the potential to promote antibiotic resistance through co-selection and maintain and promote antibiotic resistance even in the absence of antibiotics.

Background: Gang goose is a native species with gray plumage in Sichuan, China. As a result of overhunting, the number of gray Gang geese has decreased dramatically. To keep the species from extinction, conservation work for Gang geese was undertaken. In the process of pure breeding of gray Gang geese, approximately 2% of the offspring of each generation were white. This study aims to explain the genetic mechanism of this phenomenon and provide reliable molecular markers for goose-related plumage color breeding. Results: We used the method of pooled whole genome sequencing and Fst (fixation statistics) to identify the differentiation degree of alleles between gray Gang geese and white Gang geese from their offspring. In this way, EDNRB2, a key gene that affects the migration of melanoblasts, was identified. Then, the transcriptome was sequenced for the two geese plumage color populations, and the DEGs (differentially expressed genes) were analyzed. The results indicated that EDNRB2, as a possible candidate gene, had a significantly differential mRNA expression. In addition, a 14-bp insertion (NW_013185915.1: g. 750,748–750,735 insertion. CACAGGTGAGCTCT) in exon 3 of EDNRB2 was analyzed and found to have a significant association between gray geese and Chinese white breeds (P = 0.00), while this mutation was not found in European geese. Meanwhile, the insertion was homozygous in all the white geese we detected and heterozygous in gray geese, indicating that this mutation is recessive. Furthermore, this 14-bp insertion leads to a frameshift mutation in the EDNRB2 coding region and nonsense-mediated mRNA decay. Conclusion: Our study strongly suggests that the 14-bp insertion in exon 3 of the EDNRB2 gene is associated with the white plumage phenotype in Chinese geese. This study is the first to investigate the relationship between EDNRB2 and white plumage in geese.

The Jianchang duck is mainly distributed in Southwest China, and has the characteristics of fast growth rate and strong abilities in lipid deposition in the liver. In order to investigate the effects of domestication process on formation of the unique characteristics of Jianchang duck, the whole genome of sixteen individuals and three pooling of Jianchang duck were re-sequenced, and genome data of 70 mallards and 83 domestic ducks from thirteen different places in China were obtained from NCBI. The population stratification and evolution analysis showed gene exchanges existed between the Jianchang and other domestic duck populations, as well as Jianchang ducks and mallards. Genomic comparison between mallards and Jianchang ducks showed genes, including CNTN1, CHRNA9, and SHANK2, which is involved in brain and nerve development, experienced strong positive selection in the process of Jianchang duck domestication. The genomic comparison between Jianchang and domestic duck populations showed that HSD17B12 and ESM1, which affect lipid metabolism, experienced strong positive selection during the domestication process. F_ST analysis among populations of Jianchang duck with different plumage colors indicated that MITF was related to the phenotype of a white feather, while MC1R was related to the phenotype of hemp feather. Our results provided a base for the domestication process of Jianchang duck and the genomic genes for unique traits.

Introduction. Geese can naturally obtain dietary fiber from pasture, which has anti-inflammatory and antioxidant properties. This study aimed to investigate the inhibitory impacts of pasture on ameliorating LPS-ROS-induced gut barrier dysfunction and liver inflammation in geese. Materials and methods. The lipopolysaccharides (LPS), alkaline phosphatase (ALP), reactive oxygen species (ROS), tight junction proteins, antioxidant enzymes, immunoglobulins, and metabolic syndrome were determined using ELISA kits. The Kelch-like-ECH-associated protein 1-Nuclear factor erythroid 2-related factor 2 (Keap1-Nrf2) and inflammatory cytokines were determined using the quantitative reverse transcription PCR (RT-qPCR) method. The intestinal morphology was examined using the Hematoxylin and Eosin (H&E) staining method in ileal tissues. Results. Pasture significantly influences nutrient absorption (p < 0.001) by ameliorating LPS and ROS-facilitated ileal permeability (p < 0.05) and systemic inflammation (p < 0.01). Herein, the gut permeability was paralleled by liver inflammation, which was significantly mimicked by ALP-dependent Nrf2 (p < 0.0001) and antioxidant enzyme activation (p < 0.05). Indeed, the correlation analysis of host markers signifies the importance of pasture in augmenting geese’s health and production by averting gut and liver inflammation. Conclusions. Our results provide new insight into the mechanism of the pasture-induced ALP-dependent Nrf2 signaling pathway in limiting systemic inflammation in geese.