Sex-related differences of bone properties of pelvic limb and bone metabolism indices in 14-month-old ostriches (Struthio camelus).

1. Sex-related differences of long pelvic limb bones and serum bone metabolism indices were evaluated in 14-month-old female (N = 7) and male (N = 7) ostriches of similar body weights. 2. Densitometric parameters of femur, tibia and tarsometatarsus were determined using quantitative computed tomography (volumetric bone mineral density, calcium hydroxyapatite density and mean volumetric bone mineral density) and dual energy X-ray absorptiometry (bone mineral density and bone mineral content) methods. Geometrical parameters such as cortical bone area, cross-sectional area, second moment of inertia, mean relative wall thickness and cortical index were determined in the midshaft of bones. Mechanical properties of bones (maximum elastic strength and ultimate strength) were evaluated using three-point bending test. Serum concentrations of free amino acids, osteocalcin, N-terminal propeptide of type I procollagen, C-terminal telopeptides of type II collagen and total antioxidative capacity were also determined. 3. Bone weight and relative bone weight of all bones were significantly higher in males than in females. Significantly lower values of trabecular bone mineral density and calcium hydroxyapatite density were found in the trabecular bone of tibia in males. The highest number of the sex-related differences was observed in the tarsometatarsus where bone length, bone mineral content, cortical bone area, cross-sectional area and ultimate strength were higher in males. Serum concentrations of taurine, hydroxyproline, valine and isoleucine were significantly higher in males. 4. Higher loading of the tarsometatarsus in comparison to femur and tibia may be an important factor interacting with sex hormones in regulation of bone formation and mineralisation processes. Sex-related differences of bone properties were associated with increased serum concentration of selected amino acids in males.

A note on the organization and expression of ß-defensin genes in Polish goats.

Nucleotide (cds) and amino acids sequences of the caprine ß2-defensin genes were in silico compared to search for the sequence variation and for the LAP gene sequences in the goat genome and for the presence of LAP gene transcripts in goat tissues. The comparison of the exon sequences revealed that the first 64 amino acids are identical in both LAP and ß1-defensin. However, the GBD-1 prepropeptide is shorter by 18 amino acids due to the presence of the stop codon UAA at position 209-211 in GBD-1 mRNA. The LAP gene, which was found, so far, only in Indian goat breeds, is absent in the genome of Polish dairy goats. The introns of the caprine ß1- and ß2-defensin genes were, for the first time, sequenced; their sequences showed 99.6 % identity, differing in six nucleotide positions.

Twelve-year cohort study on the influence of caprine arthritis-encephalitis virus infection on milk yield and composition.

This long-term observational cohort study was carried out to evaluate the effect of caprine arthritis-encephalitis virus (CAEV) infection on the quantitative and qualitative characteristics of milk production in dairy goats. For this purpose, a dairy herd comprising both CAEV-infected and uninfected female goats was observed for 12 consecutive years. Records on daily milk yield, somatic cell count (SCC), and contents of the major milk components (fat, protein and lactose) were collected every month. In total, 3,042 records (1,114 from CAEV-positive and 1,928 from CAEV-negative animals) from 177 female goats were used for statistical analysis. The multi-trait repeatability test-day animal model using the derivative-free multivariate analysis package with the average information-REML method was applied to eliminate the influence of factors other than CAEV infection on milk production in goats. The statistical significance of the differences between estimates for seropositive and seronegative goats was evaluated using Student's t-test. The effect of age of goats (parity) on their serological status was also estimated with the one-trait repeatability test-day model. The serological status of goats was linked to parity: the higher the parity, the greater the probability of CAEV infection. No significant differences between infected and uninfected goats with respect to daily milk yield and SCC were found. On the other hand, the milk of uninfected goats contained more total protein (3.40% vs. 3.35%), fat (3.69% vs. 3.54%), and lactose (4.30% vs. 4.25%) than the milk of infected goats. Even though these differences were highly significant, they were small when expressed numerically.

The polymorphism in the beta4-defensin gene and its association with production and somatic cell count in Holstein-Friesian cows.

The aim of this study was to find a polymorphism of the bovine beta4-defensin gene and search for its association with milk yield and composition and with the somatic cell count in milk. The data were from the years 1999 to 2004 on 212 Holstein-Friesian (HF) dairy cows, descended from 70 sires. Based on the sequence of the bovine beta4-defensin gene (GenBank no. AF008307) the primers were designed for the amplification of the 924-bp or 393-bp long fragments. The 924-bp long fragment was sequenced and the sequence was compared with that available in the GenBank. Ten putative nucleotide sequence polymorphisms were found in the intron of the bovine beta4-defensin gene. One of them, a C-->T transition at position 2239, that creates a new NlaIII (Hin1II) restriction site, was genotyped with polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in a cohort of 212 HF cows. The CC genotype was the most common (72%). The heterozygous CT genotype was found in 26% of the genotyped cows and four cows (2%) were TT homozygotes. In order to determine the relationship between the polymorphism of the beta4-defensin gene and milk production traits a multi-trait repeatability test-day animal model was used. The Derivative-free Multivariate analysis program was used for computation. The differences between estimates for genotypes were checked using Student's t-test. The model included the animal genotype, year-season of calving and parity as fixed effects and the animal additive genetic effect and permanent environmental effect of individual cows as well as dates of the tests as random effects. Significant associations were found between the RFLP-NlaIII and milk fat, protein and lactose contents. Also, a significant effect was shown of the defensin genotype on the somatic cell count in the milk.