Newcastle disease (ND) caused by virulent Newcastle disease virus (NDV) is an acute, highly contagious and fatal viral disease affecting most species of birds. Ducks are generally considered to be natural reservoirs or carriers of NDV while being resistant to NDV strains, even those most virulent for chickens; however, natural ND cases in ducks have been gradually increasing in recent years. In the present study, ducks of different breeds and ages were experimentally infected with duck origin virulent NDV strain duck/Jiangsu/JSD0812/2008 (JSD0812) by various routes to investigate the pathogenicity of NDV in ducks. Six breeds (mallard, Gaoyou, Shaoxing, Jinding, Shanma, and Pekin ducks) were infected intramuscularly (IM) with JSD0812 strain at the dose of 5 × 10⁸ ELD₅₀. Susceptibility to NDV infection among breeds varied, per morbidity and mortality. Mallard ducks were the most susceptible, and Pekin ducks the most resistant. Fifteen-, 30-, 45-, 60-, and 110-day-old Gaoyou ducks were infected with JSD0812 strain at the dose of 5 × 10⁸ ELD₅₀ either IM or intranasally (IN) and intraocularly (IO), and their disease development, viral shedding, and virus tissue distribution were determined. The susceptibility of ducks to NDV infection decreased with age. Most deaths occurred in 15- and 30-day-old ducklings infected IM. Ducks infected IN and IO sometimes exhibited clinical signs, but seldom died. Clinical signs were primarily neurologic. Infected ducks could excrete infectious virus from the pharynx and/or cloaca for a short period, which varied with bird age or inoculation route; the longest period was about 7 days. The rate of virus isolation in tissues from infected ducks was generally low, even in those from dead birds, and it appeared to be unrelated to bird age and infection route. The results confirmed that some of the naturally occurring NDV virulent strains can cause the disease in ducks, and that ducks play an important role in the epidemiology of ND. The prevention of NDV spread in ducks should receive more attention and research in terms of preventing the occurrence and prevalence of ND.

To evaluate the germplasm characteristics and nutritional value of Chinese native pigeon varieties, this study analyzed the nutrient composition of the meat of four Chinese native pigeon varieties and then compared them with those of the White King pigeon, which is the most commonly used in China. A total of 150 pigeons aged 28 d (squabs) of 5 breeds including Taihu pigeon, Shiqi pigeon, Ta-rim pigeon, Boot pigeon, and White King pigeon were selected for slaughter. The basic meat quality parameters and contents of conventional nutritional compositions, inosine acid, amino acids, and fatty acids were measured. The results showed that there were significant differences in flesh color (L*, b*), pH, and water loss rate of different breeds of suckling pigeons (p < 0.05). Compared with White King pigeons, four local breeds had dark breast meat and a low water loss rate. The protein contents of Taihu, Tarim, and Shiqi suckling pigeons were significantly higher than those of White King pigeons (p < 0.05). Taihu pigeons had the highest protein content, reaching 22.72%. The inosinic acid content of Tarim pigeons was the highest (1.31 mg/g) and was significantly higher than that of Shiqi pigeons, Boot pigeons, and White King pigeons (p < 0.05). There was no significant difference in the content of amino acids, the ratio of essential amino acids, and the ratio of umami amino acids in the meat of different breeds of pigeons (p > 0.05). The percentage of saturated fatty acids (SFAs) in the breast muscle of local breeding pigeons was significantly lower than that of White King pigeons (p < 0.05), and the percentages of lauric acid, palmitic acid, eicosanoic acid, and behenic acid in SFAs reached significant levels (p < 0.05). The content of eicosapentaenoic acid (EPA) in the meat of Taihu pigeons was significantly higher than that in other breeds. In conclusion, compared with the White King pigeon, the meat of local breed pigeons (Taihu pigeon, Shiqi pigeon, Tarim pigeon, and Boot pigeon) had dark flesh, good water retention, high protein and inosine contents, a high proportion of essential amino acids, and a low saturated fatty acid ratio. In addition, Taihu pigeons had the highest protein content (22.72%), monounsaturated fatty acids (44.58%), and EPA (0.47%) compared to other breeds.

Newcastle disease (ND), caused by the virulent Newcastle disease virus (NDV), is an acute, highly contagious, and economically significant avian disease worldwide. Vaccination is the most effective measure for controlling ND. In recent years, vaccines matched with the prevalent strains of genotype VII have been developed and are now commercially available. These vaccines can provide full protection for chickens against clinical disease and mortality after challenges with genotype VII viruses and significantly decrease virus shedding compared to conventional vaccines belonging to genotypes I and II. Vaccinated hens can transfer antibodies to their offspring through the egg yolk. Maternally derived antibodies can provide passive protection against diseases but can also interfere with vaccination efficacy early in life. This study was conducted on chicks hatched from hens vaccinated with a commercial genotype VII NDV-matched vaccine to investigate the correlation between hemagglutination inhibition (HI) antibody levels in chicks and hens and the decaying pattern of maternally derived HI antibodies, and to evaluate the protective efficacy of different levels of maternally derived HI antibodies against challenge with a virulent NDV strain of genotype VII based on survivability and virus shedding. The HI antibody titers in chicks at hatching were about 1.3 log₂ lower than those in hens, indicating an antibody transfer rate of approximately 41.52%. The estimated half-life of these antibodies was about 3.2 days. The protective efficacy of maternally derived HI antibodies was positively correlated with the titer. These antibodies could effectively protect chicks against mortality when the titer was 7 log₂ or higher, but they were unable to prevent virus shedding or infection even at a high titer of 11 log₂. The obtained results will greatly assist producers in determining the immune status of chicks and formulating appropriate vaccination schedules against ND.

We aimed to identify the characteristic functional components of pigeon eggs and the differences among pigeon, chicken, and quail eggs. We analyzed the metabolite profiles of three kinds of eggs using an untargeted metabolomics-based approach to better understand the differences in metabolites among pigeon, chicken, and quail eggs. Then, we quantitatively validated the differences in abundance of partial metabolites through a targeted metabolomics-based approach. A total of 692 metabolites were identified in the three types of eggs. A total of 263 significantly differentially abundant metabolites were found between pigeon eggs and chicken eggs, and 263 significantly differentially abundant metabolites were found between pigeon eggs and quail eggs. The metabolites that were significantly more abundant in pigeon eggs than in other eggs were mainly lipids, lipid-like molecules, nucleosides, nucleotides, and their analogues. We identified the eight metabolites that were significantly greater in abundance in pigeon eggs than in chicken eggs and quail eggs and quantitatively validated the differences in abundance of these metabolites. Our study demonstrates that there are more functional components in pigeon eggs than chicken eggs and quail eggs, especially for the prevention and treatment of various disordered glucose and lipid metabolism-related diseases. The discovery of these differentially abundant metabolites paves the way for further research on the unique nutritional functions of pigeon eggs and the further utilization of pigeon egg products.

The Taihu Dianzi pigeon is a breed native to China, and its special piebalding, crest, and polydactyly phenotypes are the result of artificial and natural selection. Here, we analyzed the genetic differences among three kinds of pigeons with different phenotypes at the genomic level. A selective sweep was conducted based on the fixation index (F_ST) and nucleotide diversity (π) ratio, and the results revealed that MC1R was related to the formation of the distinctive piebalding of the Taihu Dianzi pigeon. Combined with the results of genome-wide association studies, we identified candidate genes associated with the crest (SMYD and STOX2) and polydactyly (SLC52A3 and ANGPT4). The candidate genes identified in this study and their variants may be useful for understanding the genetic mechanism underlying the special phenotypes of the Taihu Dianzi pigeon. This study provides new insights into the genetic factors that may influence the formation of the special piebalding, crest, and polydactyly characteristics in pigeons.

Mycoplasma gallisepticum (MG) and Mycoplasma synoviae (MS) are regarded as the most clinically and economically important avian Mycoplasma species, posing significant challenges to the poultry industry worldwide. In this study, MG and MS antibodies were detected by ELISA in 857 unvaccinated Chinese native chickens from 21 breeder flocks on four multi-age farms. The overall seropositive rates were 86.3% for MG and 98.4% for MS. Offspring from an infected breeder flock were reared under different environmental conditions, and serological monitoring was conducted over a 68-week production cycle. The antibody titers and seropositive rates of both mycoplasmas in birds reared in an isolation room were significantly lower than those in birds reared on the farm after maternal antibodies vanished. By adopting strict biosecurity measures, MG and MS infections were effectively controlled in an offspring flock derived from infected breeders, as evidenced by a substantial decrease in seropositive rates. The results suggested that MG and MS infections were prevalent in the breeder flocks of Chinese native chickens. Horizontal rather than vertical infection was the primary cause of high flock infection levels under field conditions. Strict biosecurity measures could be adopted to initially control MG and MS infections in offspring from the breeder flocks with high infection levels.