Search Results (14)

Coronaviruses (CoVs) were first described in poultry in the early 1930s and formally recognized as pathogens of both animal and human populations in the late 1960s. They are now considered among the most abundant viral families in the world. Though their distribution and diversity remain understudied in wild animals, representatives from 13 orders of wild birds worldwide have tested positive for CoVs of the gamma and delta genera over the last 25 years. Many of these wild bird species are in the orders Charadriiformes (shorebirds and their relatives) and Anseriformes (waterfowl including ducks, geese, and swans). Waterfowl are particularly concerning as potential reservoirs for CoVs because they are globally distributed; often congregate in large, mixed-species flocks; and may exist in close proximity to humans and domesticated animals. This review describes the history and current knowledge of CoVs in birds, provides an updated list of global detections of CoVs in 124 species of wild birds as reported in the peer-reviewed literature since 2000, and highlights topics for future research that would help elucidate the role of waterfowl in CoV transmission. Our review reiterates the need for continuous surveillance to detect and monitor CoVs across all bird species and for standardization in data reporting and analysis of both negative and positive results. Such information is critical to understand the potential role of free-ranging birds in the maintenance, evolution, and transmission of the virus. Further, we believe that research on the potential impacts of coronavirus infections and coinfections on avian demographics, especially reproduction in waterfowl, is warranted given known consequences in domestic poultry. Full article

The avian intestinal microbiota is a vital interface for host/environment interactions, playing a pivotal role in nutrient metabolism, immune regulation, and ecological adaptation. In the Yellow River Delta region, common cranes and white cranes coexist in mixed flocks. During the winter, when food resources are scarce, studying their gut microbiota can effectively reveal the feeding patterns of these two crane species, thereby providing valuable data for crane conservation efforts. This study systematically investigated and compared the intestinal microbiota structures of white cranes (Grus leucogeranus) and common cranes (Grus grus) inhabiting the Yellow River Delta region. The results demonstrated that the predominant phyla of the intestinal microbiota in white and common cranes are Firmicutes and Proteobacteria at the phylum level; Catellicoccus and Lactobacillus were the predominant genera in the crane species. LEfse was used to analyze the differential flora of the intestinal bacterial communities of white cranes and common cranes and to detect the marker species with significant differences between the groups. Based on the COG database, a preliminary functional prediction of the intestinal microbiota was conducted, and 16 metabolic pathways relating to the COG pathway were obtained. In general, although both types of cranes belong to the Grus genus and are distributed in the same area, there are significant differences in the composition and functional characteristics of their intestinal microbiota due to the differences in their feeding composition. Full article

Human-caused changes to habitats like forestry practices and traffic noise can negatively influence antipredator and foraging behavior in animals. These behavior patterns are also frequently positively influenced by individuals being part of mixed-species groups. However, we know little about how such human-induced changes impact these behaviors in individuals of mixed-species groups. To address this gap, we examined the effects of mixed-species group composition, traffic noise, and vegetation density on antipredator and foraging behavior. We used feeders to attract mixed-species flocks of Carolina chickadees (Poecile carolinensis), tufted titmice (Baeolophus bicolor), and white-breasted nuthatches (Sitta carolinensis). Once we detected a flock at a feeder, we presented a Cooper’s hawk model and recorded flocks’ seed-taking and calling behaviors. Titmice avoided feeders more when hawk models were presented at sites with greater vegetation density. Nuthatches called more quickly with more conspecifics in their flocks, and they tended to take seed more quickly with greater diversity of species in their flocks. We did not detect the effects of physical or social environmental variables on chickadee behavior. Our results reveal individual sensitivity to environmental variation in contexts involving visual predator stimuli. More work is needed to investigate how various predator stimulus modalities affect antipredator behaviors of mixed-species flock members. Full article

The flock formation of bird species is a crucial behavioral process that enables them to colonize urban areas. However, the factors influencing the structure and composition of ground-feeding bird flocks have not yet been analyzed. This study aimed to relate flock characteristics, including size, number, species richness, and composition, to local and landscape factors in the urban parks of Buenos Aires City, Argentina. Surveys of flocks were conducted in 16 parks during the breeding season, covering both mono-specific and mixed-species flocks. Flock numbers were positively correlated with tree, lawn, and bare ground cover but negatively associated with raptor presence in the parks. Flock species richness declined with increased noise and pedestrian traffic but rose in parks where raptors were present. The composition of species in flocks was linked to tree cover, noise, and the presence of raptors. While the Rock Dove (Columba livia) and the Rufous-bellied Thrush (Turdus rufiventris) were more abundant in parks with greater tree cover, the Eared Dove (Zenaida auriculata) and the Monk Parakeet (Myiopsitta monachus) showed increased abundance in more open parks. Zenaida auriculata and Columba livia experienced a decline in abundance in parks where raptors were present. Our findings indicate that resource availability and predation risk are crucial factors shaping flock formation in urban parks. Full article

Small ruminant lentiviruses (SRLVs) cause a persistent, chronic degenerative, multisystem disease in goats and sheep. This study was performed to assess the genetic distribution of SRLV in Mexico and the risk factors that favor its presence in sheep and goats across different production units. In total, 890 goats and sheep (383 and 507, respectively) from 52 mixed-species and single-species flocks in the northern, central, and southern regions of Mexico were analyzed. Serological and molecular diagnoses were conducted. PCR-positive samples were further analyzed via real-time PCR to identify genotypes A and B. The survey data were evaluated to determine the relationship between virus presence, seropositivity, and associated factors in the flocks. Of the 890 animals sampled (507 sheep and 383 goats), 40% (354/890) tested positive for antibodies specific for SRLV (229 goats and 125 sheep), while 78% (697/890) were positive for the viral genome (340 goats and 357 sheep). The results confirmed that genotype A circulated in 15% of infected animals, genotype B circulated in 66%, and 19% were co-infected with both genotypes. This study highlights the circulation and spread of SRLV genotypes A and B in goat and sheep flocks in Mexico. The risk factors that showed a significant association with seropositivity were age, flock size, and veterinary assistance. For molecular positivity detection, production with mixed flocks was added as a variable in the central region cluster, in addition to the variable knowledge of SRLV diseases and contact with other flocks in the sheep cluster. Other factors such as species cohabitation, cleanliness, and preventive measures were associated with the presence of clinical signs. Full article

Communally owned rangelands serve as critical grazing areas for mixed livestock species such as cattle and goats, particularly in the arid and semi-arid regions of Southern Africa. This study aimed to evaluate the nutritional composition and woody species composition of communal rangelands where cattle and goat flocks graze together and to investigate the influence of grazing intensity on vegetation dynamics. Vegetation surveys were conducted across varying grazing intensities to assess species richness, biomass, and dietary preferences, while soil properties were analyzed to determine their interaction with vegetation attributes. Stepwise regression and path analyses were used to explore the relationships between soil characteristics, vegetation structure, and livestock dietary choices. The results revealed that high grazing pressure significantly reduced grass biomass (p = 0.003) and woody species density (p = 0.007) while increasing shrub cover (p = 0.018). Nutritional analysis indicated that goats preferred woody shrubs, which contributed 42.1% of their diet compared to 27.8% for cattle (p = 0.008). Regression analysis further showed that soil organic carbon (p = 0.002) and tree height (p = 0.041) were strong predictors of shrub cover. Seasonal variation significantly affected forage availability and nutritional content, with higher crude protein levels recorded during the wet season (p = 0.007). These findings suggest that grazing management strategies should be tailored to the distinct forage needs of cattle and goats to maintain the productivity and ecological stability of communal rangelands. A holistic approach that considers livestock dietary preferences, vegetation composition, and soil health is essential for sustainable rangeland management in mixed-species grazing systems. Full article

Backyard poultry farming is an important tool for poverty alleviation and food security in rural areas of Morocco. A descriptive epidemiologic survey was conducted in 286 backyard poultry flocks from the provinces of Khemisset and Skhirat-Temara to gain baseline data on the current status of backyard poultry flocks in Morocco as well as its potential implications on the transmission and spread of avian diseases. The findings indicated that 88.8% of flocks were raised in a mixed confinement system, with an average flock size of 30 birds (range 1–352). Chickens accounted for 83% of the overall reported birds. More than two-thirds of respondents (69%) kept chickens only, while the remaining flocks raising multiple bird species in total promiscuity. Diseases were the highest cause of mortality (84.7%), followed by predation (15.3%). According to 56.1% of the owners, respiratory symptoms were among the major disease signs reported, besides ectoparasite infestation. Flock health management revealed a lack of preventive vaccination, lack of veterinary consulting, lack of biosecurity practices, and irrational self-medication of diseased birds using antibiotics, pesticides, and hazardous chemicals that could be a significant health risk for consumers. The need for an outreach program about disease prevention and biosecurity practices, along with prophylactic campaigns, should be emphasized to further mitigate the risks of backyard poultry flocks on the commercial sector and public health. Full article

Paramphistomidosis has recently been identified as an emerging parasitosis in Europe. This study estimated the prevalence of rumen flukes, Fasciola hepatica and Dicrocoelium dendriticum, in small ruminants in Germany and identified occurring rumen fluke species and potential predictors for fluke infections. Pooled fecal samples from 223 sheep farms and 143 goat farms in northern and southern Germany were examined by the sedimentation technique, and molecular species identification was performed on rumen-fluke-positive samples. In sheep, a flock prevalence of 2.2% was detected for rumen flukes. Calicophoron daubneyi was identified on four of five positive farms, while species identification failed in one flock. No rumen fluke eggs were detected in the examined goat herds. F. hepatica eggs were detected in 2.7% of the sheep flocks, while the herd prevalence was 5.6% in goats. Higher prevalence values of 21.1% (sheep) and 7.0% (goats) were observed for D. dendriticum. Mixed grazing with other ruminants and previously identified infections with rumen flukes and/or F. hepatica were identified as predictors for paramphistomidosis. The distribution of the three trematode species followed a geographical pattern associated with conditions favoring the relevant intermediate hosts. C. daubneyi is an established parasite in German sheep at a currently low prevalence. Full article

Small ruminant lentiviruses (SRLVs) are a group of highly divergent viruses responsible for global infection in sheep and goats. In a previous study we showed that SRLV strains found in mixed flocks in Poland belonged to subtype A13 and A18, but this study was restricted only to the few flocks from Małopolska region. The present work aimed at extending earlier findings with the analysis of SRLVs in mixed flocks including larger numbers of animals and flocks from different part of Poland. On the basis of gag and env sequences, Polish SRLVs were assigned to the subtypes B2, A5, A12, and A17. Furthermore, the existence of a new subtypes, tentatively designed as A23 and A24, were described for the first time. Subtypes A5 and A17 were only found in goats, subtype A24 has been detected only in sheep while subtypes A12, A23, and B2 have been found in both sheep and goats. Co-infection with strains belonging to different subtypes was evidenced in three sheep and two goats originating from two flocks. Furthermore, three putative recombination events were identified within gag and env SRLVs sequences derived from three sheep. Amino acid (aa) sequences of immunodominant epitopes in CA protein were well conserved while Major Homology Region (MHR) had more alteration showing unique mutations in sequences of subtypes A5 and A17. In contrast, aa sequences of surface glycoprotein exhibited higher variability confirming type-specific variation in the SU5 epitope. The number of potential N-linked glycosylation sites (PNGS) ranged from 3 to 6 in respective sequences and were located in different positions. The analysis of LTR sequences revealed that sequences corresponding to the TATA box, AP-4, AML-vis, and polyadenylation signal (poly A) were quite conserved, while considerable alteration was observed in AP-1 sites. Interestingly, our results revealed that all sequences belonging to subtype A17 had unique substitution T to A in the fifth position of TATA box and did not have a 11 nt deletion in the R region which was noted in other sequences from Poland. These data revealed a complex picture of SRLVs population with ovine and caprine strains belonging to group A and B. We present strong and multiple evidence of dually infected sheep and goats in mixed flocks and present evidence that these viruses can recombine in vivo. Full article

This study is part of a 2 year disease surveillance project conducted to establish the prevalence of poultry and zoonotic pathogens, including Campylobacter spp., among small poultry flocks in Ontario, Canada. For each post-mortem submission to the Animal Health Laboratory, a pooled sample of cecal tissue was cultured for Campylobacter spp., and a husbandry and biosecurity questionnaire was completed by the flock owner (n = 153). Using both laboratory and questionnaire data, our objective was to investigate demographic, husbandry, and biosecurity factors associated with the presence of Campylobacter spp. in small flocks. Two multivariable logistic regression models were built. In the farm model, the odds of Campylobacter spp. were higher in turkeys, and when birds were housed in a mixed group with different species and/or types of birds. The odds were lower when antibiotics were used within the last 12 months, and when birds had at least some free-range access. The effect of pest control depended on the number of birds at risk. In the coop model, the odds of Campylobacter spp. were lower when owners wore dedicated clothing when entering the coop. These results can be used to limit the transmission of Campylobacter spp. from small poultry flocks to humans. Full article

Behaviour signals the internal states that relate to an individual’s welfare and its development is influenced by the early social environment that an animal experiences. Husbandry practices can alter this early social environment, for example different rearing conditions (e.g., foster rearing by a surrogate parent of another species). Widespread implementation of altered rearing can lack empirical support and non-parent-reared animals may experience poorer welfare resulting from maternal deprivation. An opportunity presented itself to measure the effect of foster-rearing on Chilean flamingo behaviour and social preferences at WWT Slimbridge Wetland Centre and compare findings to parent-reared conspecifics in the same time period. Data were collected from April to July 2019 at three timepoints during each observation day. Binomial generalized linear mixed models were used to assess the relationship between focal chicks’ rearing background with behaviour, zone usage, and flock position whilst accounting for climatic factors and visitor numbers. The development of social preferences was assessed using social network analysis. Our results showed limited impacts on flamingo behavioural development due to foster rearing. Foster-reared chicks spent less time feeding, were more likely to occupy the nesting area of the enclosure, and had fewer significant preferred associations than parent-reared chicks, but preferred social bonds were as equally strong and durable for both foster-reared and parent-reared chicks. Our results have important welfare implications for the use of foster-rearing in captive environments; altered early social rearing environments through cross-fostering in Chilean flamingos is associated with limited differences in behavioural and social development. Full article

The family Ciconiidae comprises 19 extant species which are highly social when nesting and foraging. All species share similar morphotypes, with long necks, a bill, and legs, and are mostly coloured in the achromatic spectrum (white, black, black, and white, or shades of grey). Storks may have, however, brightly coloured integumentary areas in, for instance, the bill, legs, or the eyes. These chromatic patches are small in surface compared with the whole body. We have analyzed the conservatism degree of colouration in 10 body areas along an all-species stork phylogeny derived from BirdTRee using Geiger models. We obtained low conservatism in frontal areas (head and neck), contrasting with a high conservatism in the rest of the body. The frontal areas tend to concentrate the chromatic spectrum whereas the rear areas, much larger in surface, are basically achromatic. These results lead us to suggest that the divergent evolution of the colouration of frontal areas is related to species recognition through visual cue assessment in the short-range, when storks form mixed-species flocks in foraging or resting areas. Full article

Diversity of gut microbes is influenced by many aspects, including the host internal factors and even direct or indirect contact with other birds, which is particularly important for mixed-species wintering waterbird flocks. In this study, Illumina high-throughput sequencing was used to analyze the intestinal bacteria of the hooded crane and bean goose whose niches overlap at Shengjin Lake. We tested whether contact time enhances the trans-species spread of gut bacteria. Results indicate alpha-diversity and microbial composition displayed significant separation between the two hosts in every wintering period, although the number of bacteria types shared increased with increasing contact time. For the same species, with the lengthening of contact time, alpha-diversity and the number of operational taxonomic units (OTUs) in the host intestine augmented, and the common OTUs and structural similarity of microflora in the middle and late periods were more than in the early and middle periods. In addition, we found a very high proportion of shared pathogens. Our results indicate that, although intestinal microflora of different species were separated, direct or indirect contact in the mixed-species flock caused the spread of gut bacteria trans-species, indicating that more attention should be paid to intestinal pathogens in wild birds. Full article

Foraging is the key behavior of waterbirds, which profoundly affects the survival of their population, and it is affected by interspecific interaction. At Shengjin Lake in China, owing to the reduced availability of suitable habitats for a large population of migratory waterbirds (especially wild geese) over winter, mixed species foraging inevitably occurs. This study aimed to investigate whether mixed-species foraging affects the foraging of hooded cranes (Grus monacha). Fields surveys were carried out at Shengjin Lake from November 2018 to March 2019. Mixed-species foraging was surveyed between the flocks of hooded cranes and three species of geese, greater white-fronted geese (Anser albifrons), lesser white-fronted geese (Anser erythropus) and bean geese (Anser fabalis). Instantaneous scanning and focal animal methods were used to collect behavioral samples of hooded cranes. The quadrat method was used to survey the food density in three habitats: meadows, mudflats, and paddy fields. The results showed that the foraging success rate of hooded cranes was not significantly correlated with food density and the relative flock size in the mixed-species foraging flock in meadows, but a significant negative correlation with the relative flock size in mudflats. However in paddy fields it was a significant positive correlation with the relative flock size. Foraging efforts of hooded cranes were negatively correlated with food density and positively correlated with the relative flock size in meadows. In mudflats, foraging efforts of hooded cranes had a significant positively correlation with the relative flock size, however, there was a significant negative correlation with the relative flock size in paddy fields. To sum up, larger numbers of geese mixed with hooded cranes has a favorable effect on the foraging of hooded cranes in meadows and mudflats, however, the reverse was observed in the paddy fields. Full article