Severe asynapsis in spermatocytes of interspecific hybrids of the silver fox (Vulpes vulpes) and the blue fox (Alopex lagopus) leads to pachytene I arrest as a result of sustained H2AXγ phosphorylation.

Infertility is frequently associated with meiotic anomalies which can result in the production of chromosomally abnormal gametes or be concomitant with meiotic arrest. We investigated whether spermatocytes of male interspecific hybrids of the red fox (Vulpes vulpes) and the arctic fox (Alopex lagopus) presented alterations in chromosomal synapses and meiotic checkpoint signalling. Using the immunofluorescence technique with SP1 and SP3 proteins, bivalent structures and their deviations (multivalents, univalents and not fully conjugated bivalents) were analyzed on meiotic preparations. This technique allowed the localization of frequent foci of phosphorylated histones H2AHγ (Ser 139) to the meiotic block in late pachytene. These results indicate a disruption of meiotic division in male fox hybrids, which leads to a high percentage of apoptotic cells in the gonads of these animals and, consequently, sterility.

Intestinal mucosa develops in a sex-dependent manner in Japanese quail (Coturnix japonica) fed Saccharomyces cerevisiae.

1. The aim of study was to investigate whether the impact of the yeast Saccharomyces cerevisiae on the histological structure of the intestine, innervation of the small intestine wall, and basal biochemical serum parameters in Japanese quail was sex dependent. 2. One-day-old healthy male and female Japanese quail were fed either a basal diet containing no yeast (control group) or the basal diet plus 1.5% (15 g/kg of diet) of yeast (S. cerevisiae inactivated by drying). Samples from the duodenum and jejunum were taken from each bird at the age of 42 days. Blood samples were collected at this age and the concentrations of glucose, total protein, creatinine, uric acid, lipid profile (total cholesterol, low density lipoproteins (LDL), high density lipoproteins (HDL) and triacylglycerols (TG)), alanine aminotransferase (ALAT), aspartate aminotransferase (AspAT), lactate dehydrogenase (LDH), amylase (AMY), calcium, phosphorus and iron were determined. 3. Female quail fed diets supplemented with yeast had significantly lower total cholesterol and amylase activity than the control females. The concentration of HDL was higher in the male quail than in the females, irrespective of the treatment. An opposite effect was observed in LDL. The diet treatments influenced the activity of AspAT, which was significantly less in the male quail fed diets with 1.5% yeast. 4. Supplementation with S. cerevisiae increased the myenteron, submucosa and mucosa thickness, villus length and thickness and size of absorptive surface, while the number of villi and enterocytes were decreased in the duodenum in males. Female quail showed an increased absorptive surface in the jejunum. The Meissner (submucosal) plexuses were influenced by the feeding and sex to a greater extent than the Auerbach plexus (in the muscularis propria). 5. The results demonstrated that S. cerevisiae (1.5%) in the diet caused significant positive effects in Japanese quail, exerting an effect on the morphology of the small intestine in a sex-dependent manner.

Identification of quantitative trait loci affecting production and biochemical traits in a unique Japanese quail resource population.

The objective of the current study was to identify QTL associated with body weight, growth rate, egg quality traits, concentration of selected blood plasma, and yolk lipids as well as concentration of selected macro- and microelements, color, pH, basic chemical composition, and drip loss of breast muscle of Japanese quail (Coturnix japonica). Twenty-two meat-type males (line F33) were crossed with twenty-two laying-type females (line S22) to produce a generation of F1 hybrids. The F2 generation was created by mating 44 randomly chosen F1 hybrids, which were full siblings. The birds were individually weighed from the first to eighth week of age. At the age of 19 wk, 2 to 4 eggs were individually collected from each female and an analysis of the egg quality traits was performed. At slaughter, blood and breast muscles were collected from 324 individuals of the resource population. The basic chemical composition, concentration of chosen macro- and microelements, color, pH, and drip loss were determined in the muscle samples. The concentration of chosen lipids was determined in egg yolk and blood plasma. In total, 30 microsatellite markers located on chromosome 1 and 2 were genotyped. QTL mapping including additive and dominance genetic effects revealed 6 loci on chromosome 1 of the Japanese quail affecting the egg number, egg production rate, egg weight, specific gravity, egg shell weight, concentration of Na in breast muscle. In turn, there were 9 loci on chromosome 2 affecting the body weight in the first, fourth, and sixth week of age, growth rate in the second and seventh week of age, specific gravity, concentration of K and Cu in breast muscle, and the levels of triacylglycerols in blood plasma. In this study, QTL with a potential effect on the Na, K, and Cu content in breast muscles in poultry and on specific gravity in the Japanese quail were mapped for the first time.

Effects of L-carnitine on morphology and cellular parameters of hen erythrocytes.

The aim of our study was to determine the influence of L-carnitine (L-CAR) on the cellular parameters of hen erythrocytes during a 48 hour exposure to L-CAR at concentrations of 25, 50 and 100 µg/mL in nutrient-deficient medium. Cell morphology, haemolysis, caspase 3/7 activity and glucose uptake (GU) were determined. The results showed a lower percentage of apoptotic cells and decreased haemolysis of erythrocytes treated for 48 hours at all the concentrations of L-CAR. The amino acid at 50 µg/mL inhibited the activity of proapoptotic caspase 3/7; however, it increased GU. In contrast, caspase 3/7 level was increased but GU was decreased in erythrocytes treated with 100 µg/mL of L-CAR when compared to the control. It may be hypothesized that reduction of apoptotic changes in hen erythrocytes may result from increased GU.

Long-bone properties and development are affected by caponisation and breed in Polish fowls.

1. The aim of the study was to investigate the effects of caponisation on bone development of males of two native breeds in Poland. 2. The weight, length and cross-sectional area of tibiae and femora were measured, densitometric measurements and tests of strength were determined and dimensions were calculated. 3. Breed and caponisation did not influence bone weight and length. Higher mechanical strength of the femur was found in entire males, mainly in the Polbar breed. Tibial strength was reduced in capons of the Green Partridge breed. Maximum elastic strength was greater in the Polbar, irrespective of caponisation. Bone cross-sectional area was influenced by breed, while caponisation reduced femoral bone mineral density in both breeds. 4. Caponisation thus increased growth rate but had adverse effects on bone development. 5. Caponisation had fewer negative effects in the Polbar than in the Greenleg Partridge.

High molecular polymorphism of the hypervariable region in the VP2 gene of Aleutian mink disease virus.

Parvoviruses exhibit extreme genetic plasticity. The VP2 protein, containing a hypervariable region, is of particular importance. A single nucleotide change in this part of the genome and its effect on the amino acid sequence may significantly affect the range of infected hosts, tropism for specific tissues, or virulence. The high polymorphism in the hypervariable region can be exploited for phylogenetic analysis. The aim of this study was to analyze the polymorphism of the VP2 hypervariable region in isolates of the Aleutian mink disease virus (AMDV) infecting Polish mink farms and to determine the phylogenetic relationships between the Polish isolates and genetic variants of the pathogen occurring in other countries. The study compares farms from two regions of Poland. The isolates contained five changes in the amino acid sequence, which had not previously been recorded in the NCBI database. There were 21 changes noted between the genotypes obtained and the sequence of the reference strain [GenBank NC_001662.1], of which 8 were in the hypervariable region. The isolates identified in our study exhibit a high degree of similarity within the farms, but between farms there is considerable variation in the amino acid sequence of the VP2 protein fragment. Because variants characteristic for farms were obtained, it will be possible to trace the movement of the virus between farms, and in the longer term to use the characteristic sequences as a marker of the origin of infected animals.