Missing history of a modern domesticate: Historical demographics and genetic diversity in farm-bred red fox populations.

The first record of captive-bred red foxes (Vulpes vulpes) dates to 1896 when a breeding enterprise emerged in the provinces of Atlantic Canada. Because its domestication happened during recent history, the red fox offers a unique opportunity to examine the genetic diversity of an emerging domesticated species in the context of documented historical and economic influences. In particular, the historical record suggests that North American and Eurasian farm-bred populations likely experienced different demographic trajectories. Here, we focus on the likely impacts of founder effects and genetic drift given historical trends in fox farming on North American and Eurasian farms. A total of 15 mitochondrial haplotypes were identified in 369 foxes from 10 farm populations that we genotyped (n = 161) or that were previously published. All haplotypes are endemic to North America. Although most haplotypes were consistent with eastern Canadian ancestry, a small number of foxes carried haplotypes typically found in Alaska and other regions of western North America. The presence of these haplotypes supports historical reports of wild foxes outside of Atlantic Canada being introduced into the breeding stock. These putative Alaskan and Western haplotypes were more frequently identified in Eurasian farms compared to North American farms, consistent with historical documentation suggesting that Eurasian economic and breeding practices were likely to maintain low-frequency haplotypes more effectively than in North America. Contextualizing inter- vs. intra-farm genetic diversity alongside the historical record is critical to understanding the origins of this emerging domesticate and the relationships between wild and farm-bred fox populations.

A comparative molecular characterization of AMDV strains isolated from cases of clinical and subclinical infection.

The Aleutian mink disease virus (AMDV) is one of the most serious threats to modern mink breeding. The disease can have various courses, from progressive to subclinical infections. The objective of the study was to provide a comparative molecular characterization of isolates of AMDV from farms with a clinical and subclinical course of the disease. The qPCR analysis showed a difference of two orders of magnitude between the number of copies of the viral DNA on the farm with the clinical course of the disease (105) and the farm with the subclinical course (103). The sequencing results confirm a high level of homogeneity within each farm and variation between them. The phylogenetic analysis indicates that the variants belonging to different farms are closely related and occupy different branches of the same clade. The in silico analysis of the effect of differences in the sequence encoding the VP2 protein between the farms revealed no effect of the polymorphism on its functionality. The close phylogenetic relationship between the isolates from the two farms, the synonymous nature of most of the polymorphisms and the potentially minor effect on the functionality of the protein indicate that the differences in the clinical picture may be due not only to polymorphisms in the nucleotide and amino acid sequences, but also to the stage of infection on the farm and the degree of stabilization of the pathogen-host relationship.

Citric acid as a factor limiting changes in the quality of table eggs during their storage.

The aim of the experiment was to evaluate the potential use of citric acid as a modifier of quality changes in table eggs during their storage. About 780 table hen eggs were collected on the same day. They were numbered individually and placed on trays 30 pcs on each. Control group (CA0) consisted of eggs unmodified with any additional substances. In experimental groups CA10 and CA15, eggshells were sprayed with the aqueous solution of citric acid (10 and 15% concentration, respectively). At the start of the experiment, only quality traits of eggs from the control group were analyzed. The remaining eggs were stored at 14°C and 70% RH (typical storage conditions). Their quality was evaluated after 7, 14, 21, and 28 d. The depth of the air cell, egg weight and specific gravity, traits of shell (permeability, strength, weight, thickness, density), and egg content (pH of yolk and albumen, Haugh units, yolk weight and color) were evaluated each time. The use of citric acid decreased the severity of qualitative changes. Citric acid-treated eggs demonstrated smaller weight loss, shallower air cell, higher structural albumen, less-intensive water diffusion from albumen to yolk indicating the improved resistance of the vitelline membrane. Owing to the fact that citric acid is accepted and recognized as a safe food preservative is a relatively cheap and available substance, it seems that it can be used to inhibit quality changes in table eggs during their storage.

Growth performance and meat quality of meat-type guinea fowl fed different commercial diets.

The aim of study was to assess the growth performance, meat quality, and fatty acid composition of meat-type guinea fowl fed balanced commercial diets under two different feeding programs, similar to those for slaughter turkeys and broiler chickens, respectively. A total of 80 4-week-old meat-type guinea fowl divided into two groups (four replicates per group; 10 birds in each replicate) were raised for 14 weeks. One group received commercially available diets in a three-phased program (TM group), whereas the other group was fed commercial diets in a two-phased program (CM group). Growth-performance-related traits were recorded. At the end of rearing (14 weeks of age), eight birds from each group were slaughtered. Carcass yield and technological traits of meat (pH, color, water-holding capacity, natural and thermal loss, tenderness, fatty acid profile) were analyzed. Groups did not differ in terms of body weight as well as carcass yield and characteristics. There was no difference in meat quality and the fatty acid profile of breast and thigh meat of guinea fowl from TM and CM groups. The findings of this study suggest that both commercial diets (for broiler chickens and turkeys) can be used in meat-type guinea fowl rearing. Due to the lower price of diets fed to the CM group and the lack of significant variation in meat quality traits, its use seems to be more justified from an economic point of view.

Aleutian Mink Disease Virus in the breeding environment in Poland and its place in the global epidemiology of AMDV.

Aleutian mink disease (AMD) leads to an increase in mortality of animals and causes losses in mink farming. The study investigated the presence of AMDV in tissue and environmental samples from farmed mink in Poland, and selected samples were genetically characterized. Blood, spleens and swabs from the breeding environment were collected on 27 farms in seven voivodeships in Poland (n = 250). DNA was isolated, amplified by PCR and subsequently subjected to sequencing to reveal information on the molecular epidemiology of the samples. A qPCR method was used to determine the viral load in test samples. The presence of AMDV was confirmed in tissues and the farm environment on 26 of the 27 farms. The average viral load in spleens was 108 copies. The virus was also present in the blood (average - 105 copies) and the farm environment (average - 103 copies). Isolates from the West Pomeranian Voivodeship showed high similarity within the voivodeship (over 99%). Variants from the Lublin and Podlaskie Voivodeships differed 5% from any of the AMDV isolates present in the NCBI database. Isolates from the Greater Poland, Pomeranian, Podkarpackie and Lesser Poland Voivodeships formed heterogeneous clades, showing over 97% similarity to variants previously isolated in Poland, the Netherlands and Lithuania. A high degree of genetic variation was identified among the majority of the samples, which indicates that AMDV has been introduced to Poland multiple times. However, the results within one area showed high identity between isolates, suggesting that one common ancestor was the source of these outbreaks.

Microsporidia Nosema spp. - obligate bee parasites are transmitted by air.

Microsporidia Nosema are transferred among bees via the faecal-oral route. Nosema spp. spores have been detected on flowers and transferred to hives along with the bee pollen. The aim of the present study was to determine whether Nosema microsporidia are transferred by air in an apiary, in a control area (without the presence of bee colonies), and/or in a laboratory during cage experiments with artificially infected bees. The novel way of transmission by air was investigated by the volumetric method using a Hirst-type aerobiological sampler located on the ground in the apiary, in the Botanical Garden and on the laboratory floor. Concurrently, the mean rate of Nosema infections in the foragers in the apiary was estimated with the Bürker haemocytometer method. Spore-trapping tapes were imaged by means of light microscopy, Nomarski interference contrast microscopy and scanning electron microscopy. The highest concentration of Nosema spores per 1m3 of air (4.65) was recorded in August, while the lowest concentration (2.89) was noted in July. This was confirmed by a Real-Time PCR analysis. The presence of N. apis as well as N. ceranae was detected in each of the tested tapes from the apiary. The average copy number of N. apis was estimated at 14.4 × 104 copies per 1 cm2 of the tape; whereas the number of N. ceranae was 2.24 × 104 copies per tape per 1 cm2. The results indicate that Nosema microsporidia were transferred by the wind in the apiary, but not in the Botanical Garden and laboratory by air. This was confirmed by genetic analyses. DNA from immobilised biological material was isolated and subjected to a PCR to detect the Nosema species. A fragment of the 16S rRNA gene, characteristic of Nosema apis and N. ceranae, was detected. Our research adds knowledge about the transfer of Nosema spp. microsporidia in the natural environment and indicates the season associated with the greatest risk of a bee colony infection with Nosema spp.