Juraj Grizelj

Concentrations of total proteins and albumins, and AST, AP, CK and GGT activities in the blood serum Boer and Saanen goats during puerperium.

The metabolism of proteins in the blood serum in Boer and Saanen goats was investigated during puerperium. Twenty Boer goats (10 primiparous and 10 pluriparous) and 10 Saanen goats (five primiparous and five pluriparous) between 2 and 5 years of age were used in this research. Blood for analysis was taken every fourth day from day 3 until day 40 post-partum. Blood samples were collected by jugular puncture. In the obtained blood serum, the concentration of total proteins (PT) and albumin (ALB), and the activity of enzymes aspartate aminotransferase (AST) [the Enzyme Commission number (EC number) 2. 6. 1. 1.], gamma-glutamyltransferase (GGT) (EC 2. 3. 2. 2.), creatine kinase (CK) (EC 2. 7. 3. 2.) and alkaline phosphatase (AP) (EC 3. 1. 3. 1.) were determined by spectrophotometry. These parameters were in physiological ranges in Boer goats and in Saanen goats, without significant differences according to number of kids per doe. According to the research results of the blood serum in goats during puerperium, there were no significant differences in the concentration of ALB. Boer goats had significant higher (p < 0.05) concentration of PT and enzyme activity of AP, CK and GGT. Saanen goats had only enzyme activity of AST significantly higher (p < 0.05). Enzyme activity of alkaline phosphatase was significant higher (p < 0.05) in pluriparous goats in both breeds than in primiparous. The obtained results may represent a contribution to a better understanding of protein metabolism during puerperium in dairy and meat goats and for diagnostic purposes.

Ligand-independent canonical Wnt activity in canine mammary tumor cell lines associated with aberrant LEF1 expression

Pet dogs very frequently develop spontaneous mammary tumors and have been suggested as a good model organism for breast cancer research. In order to obtain an insight into underlying signaling mechanisms during canine mammary tumorigenesis, in this study we assessed the incidence and the mechanism of canonical Wnt activation in a panel of 12 canine mammary tumor cell lines. We show that a subset of canine mammary cell lines exhibit a moderate canonical Wnt activity that is dependent on Wnt ligands, similar to what has been described in human breast cancer cell lines. In addition, three of the tested canine mammary cell lines have a high canonical Wnt activity that is not responsive to inhibitors of Wnt ligand secretion. Tumor cell lines with highly active canonical Wnt signaling often carry mutations in key members of the Wnt signaling cascade. These cell lines, however, carry no mutations in the coding regions of intracellular Wnt pathway components (APC, β-catenin, GSK3β, CK1α and Axin1) and have a functional β-catenin destruction complex. Interestingly, however, the cell lines with high canonical Wnt activity specifically overexpress LEF1 mRNA and the knock-down of LEF1 significantly inhibits TCF-reporter activity. In addition, LEF1 is overexpressed in a subset of canine mammary carcinomas, implicating LEF1 in ligand-independent activation of canonical Wnt signaling in canine mammary tumors. We conclude that canonical Wnt activation may be a frequent event in canine mammary tumors both through Wnt ligand-dependent and novel ligand–independent mechanisms.

Extensive polymorphism of the major histocompatibility complex DRA gene in Balkan donkeys: perspectives on selection and genealogy.

The major histocompatibility complex (MHC) contains genes important for immune response in mammals, and these genes exhibit high polymorphism and diversity. The DRA gene, a member of the MHC class II family, is highly conserved across a large number of mammalian species, but it displays exceptionally rich sequence variations in Equidae members. We analyzed allelic polymorphism of the DRA locus in 248 donkeys sampled across the Balkan Peninsula (Albania, Bulgaria, Croatia, Macedonia, Greece and Montenegro). Five known alleles and two new alleles were identified. The new allele Eqas-DRA*0601 was found to carry a synonymous mutation, and new allele Eqas-DRA*0701, a non-synonymous mutation. We further analyzed the historical selection and allele genealogy at the DRA locus in equids. Signals of positive selection obtained by various tests were ambiguous. A conservative conclusion is that DRA polymorphism occurred relatively recently and that positive selection has been acting on the DRA locus for a relatively brief period.

The influence of sex on biochemical markers of bone turnover in dogs

Biochemical markers of bone turnover have been shown to be useful as inexpensive and noninvasive tools for monitoring skeletal health. The reference range for bone markers in dogs has been set by different age groups. However, other sources of biological variations were not fully investigated in dogs. To explore whether sex influences the interpretation of bone marker data we examined serum bone markers in 33 male and 25 female dogs. The bone markers selected for this study were: bone alkaline phosphatase (BALP) and osteocalcin (OC) as indicators of bone formation, and C-terminal telopeptide (CTx) of type I collagen as marker of bone resorption. All concentrations of bone markers were lower, but still within the reference range reported for dogs. We found statistically significant differences of the median OC and CTx serum concentrations between males and females. The results of this study suggest that there are sex differences in biochemical markers of bone turnover in dogs which should be considered in interpretation of bone marker data.

Influence of different therapy approaches - with or without manual extraction - of retained placenta on reproductive performance in simmental cows

The aim of the research was to determine the influence of different methods used in the therapy of retained placenta on conception rate and duration of days open in cows. Research was performed on 241 Simmental cows aged 2-8 years divided in three groups. The first group of cows (group A) (n=82) with retained placenta was treated with manual extraction of placenta 12-24 h after parturition combined with application of intrauterine antibiotics. The second group (group B) (n=79) with retained placenta was treated with intrauterine antibiotics only 12-24 h after parturition and repeated 2-3 times in 48 h intervals. The third group (group C) (n=80) was the control group and had physiological puerperium (without retained placenta). To assess the reproductive performance of Simmental cows, interval from calving to first insemination (days open to first service, DOFS), interval from calving to pregnancy (days open to pregnancy, DOP), relative pregnancy rate (%), first service conception rate (FSCR, %) and all service conception rate (ASCR, %) were measured. The estimate of hazard ratio for DOFS in group A relative to cows in group B was 2.20 (p<0.0001), implying that cows in group B had oestrus earlier and were open shorter until the first insemination, that is, the relative rate of first service decreased by 54.5% in the group A while holding all other variables constant. The variable that had a significant influence on DOFS was lactation (HR=0.99; p<0.0001). The estimate of hazard ratio for DOP in group A relative to cows in group B and C was 3.53 (p<0.0001) and 1.73 (p<0.0001), respectively, implying that cows in group B and C were open longer until pregnancy, that is, the relative rate of pregnancy in group A decreased by 71.6% and 42.2% in comparison with group B and C while holding all other variables constant. Variables that had a significant influence on DOP were lactation (HR=0.99; p<0.0001) and peripartal diseases (HR=0.48; p=0.02). The estimate of hazard ratio for DOFS and DOP between group B and C was not significant. Cows treated with intrauterine foaming tablets after RFM became pregnant earlier and had a better conception rate in contrast to cows treated with manual extraction of placentae.

The reinsertion of controlled internal drug release devices in goats does not increase the pregnancy rate after short oestrus synchronization protocol at the beginning of the breeding season

ABSTRACT This study aimed to evaluate the effect of reinserting controlled internal drug release (CIDR) devices after fixed-time artificial insemination (FTAI) on pregnancy rates in goats. Oestrus was synchronized with a short (5 days) CIDR protocol, and FTAI was conducted 54 hours after CIDR removal. According to the reinsertion of CIDR after FTAI, goats were assigned to three treatments: G0 control group (n = 29), no CIDR reinsertion; G7 group (n = 27), CIDR reinserted 7 days; G14 group (n = 29), CIDR reinserted 14 days. Blood samples were collected to determine progesterone levels. Oestrus appearance (92.9%), interval of CIDR removal to oestrus (IRE = 34.1 ± 1.1 hours), interval of oestrus onset to artificial insemination (IEAI = 20.2 ± 1.0 hours), mean duration of oestrus (38.4 ± 1.4 hours), and pregnancy rates (61.0%) were similar (P > .05) among groups. Progesterone concentrations were higher (P < .05) in G7 and G14 than G0 goats. G7 goats had lower (P < .05) oestrus rate, after CIDR reinsertion, than G0 and G14 goats. Overall pregnancy rate was similar (P > .05) for all groups. In conclusion, reinsertion of CIDR for 7 or 14 days after a short oestrus synchronization protocol and FTAI did not increase the overall pregnancy rate of goats.

Ultrasound Examination of Cows During the Puerperium in Everyday Veterinary Practice

Regular control of cows during puerperium allows as detecting and treating pathological processes in the early phase, to optimise duration of service and calving period followed with the occurrence of physiological cycles. The application of ultrasound in daily practice enables precise detection of follicles ability for ovulation and identification of functional corpus lutei, early diagnose of pregnancy, determination of foetal sex as well as an early and accurate identification of pathological processes (metritis, endometritis and pyometra). This survey included 54 cows: experimental group consist of 32 animals (26 of Simmental and 6 of Holstein-Friesian breed) that were under continuous control of the veterinarian (routine gynaecological and ultrasound examination), while remaining 22 animals in the barn (12 Simmental and 10 Holstein-Friesian cows) served as a control group – inseminated only at the invitation of the owner. Insemination index (1.69) and duration of service period (82.27 days) in the experimental group of Simmental cows were significantly lower (P<0.001) than in the control group (3.25 and 155.17 days, respectively). Although smaller insemination index was observed in experimental group of Holstein-Friesian cows (2.17) compared to the control (3.10) this difference wasn’t significant. Also, service period (100.67 days) in the experimental group was significantly shorter (P<0.05) compared to the control animals (180.30 days). These results showed that application of ultrasound improved certain fertility indicators in cows, i.e. minus insemination index and shortened duration of service period.

The efficacy of milk ejection induced by luteal oxytocin as a method of early pregnancy diagnostics in cows

The aim of this research was to determine the accuracy and reliability of early diagnosis of pregnancy in cows using PGF2α analogue. Namely in the case of corpus luteum (CL) presence, the release of luteal oxytocin is induced by intravenous administration of a non luteolytic dose of PGF2α. The research was performed in 30 lactating cows, 18-22 days after insemination, and three hours prior to evening milking. A teat cannula is placed in the left fore-teat. When the cisternal milk flow ceased, Dinoprost (256 μg Dinolytic) was injected in the v. jugularis. If CL was present, the alveolar milk flow (559.4±83.7 mL) started 189±18 s later and early pregnancy could be presumed. If CL was no longer functional, the milk flow did not start again and the cow was considered not pregnant. Seventeen out of 30 cows were confirmed pregnant 35 days after insemination by ultrasound and 13 were found not pregnant. The accuracy of positive results is 100% and is identical to that obtained by ELISA of milk progesterone used as a reference method. The accuracy of negative results was lower (46.1% vs. 84.6%) (p<0.05), because seven out of 13 non pregnant cows has responded to the milk ejection test. In spite of this disadvantage, the test approved as being inexpensive, rapid, and easy to interpret and is therefore very applicable, especially under field conditions. It can be applied i.e. 20 days after insemination. Progesterone rapid test from milk or by milk ejection test can be used with similar accuracy.