Miljenko Konjačić

Genetic structure of three Croatian horse breeds: implications for their conservation strategy

Abstract The genetic variability for a sample of 107 animals from three autochthonous Croatian horse breeds was estimated using 20 microsatellites. The average number of alleles per locus (6.3) and proportion of heterozygosity (0.732) indicated a moderate variability. The expected heterozygosity was similar among all breeds and ranged between 0.724 in the Posavina horse, and 0.737 in the Croatian Coldblood and Murinsulaner horse. The inbreeding coefficient Fis was low and non-significant over the three populations. The genetic differentiation among the three populations was low (Fst=0.026), suggesting that only 2.6% of the total genetic variability was due to differences between the breeds, and 97% to individual differences. The results of pairwise genetic differentiation suggest that the Posavina horse and the Croatian Coldblood were the most closely related populations (Fst=0.016). These results are confirmed by Nei’s genetic distances with the highest value observed between the Posavina horse and the Murinsulaner (0.082) and the lowest between the Posavina horse and the Croatian Coldblood (0.044). An assignment test correctly assigned 82% of individuals to the correct breed. Strategies for preserving the original native genes in the Croatian native horse breeds should be considered in order to prevent these breeds from becoming extinct and include them in the future breeding programmes.

Effect of breed and age on beef carcass quality, fatness and fatty acid composition

Abstract. The aim of this research was to determine differences in beef carcass fatness and in the fatty acid composition of muscle and adipose tissue of three different breeds slaughtered at the age of 14 months and 19 months. The breed significantly affected the muscle fat content, carcass subcutaneous fat tissue thickness and fatty acid composition of the muscle and subcutaneous fat tissue. Different age at slaughter had no significant effect on analysed traits. The muscle tissue of the Herefords contained a higher (P

A study of chemical profiles and appearance of white crystals in Istrian dry-cured ham: effect of desalting

Abstract In order to find out the effect on physical-chemical profile of Istrian dry-cured ham with particular regard to the appearance of white crystals in the muscles, raw salted legs were desalted by soaking the legs in cold water for 24 hours. The 20 raw hams taken from 10 slaughtered hogs (Swedish Landrace breed) and processed in the traditional Istrian manner were used. After salting and pressing, the raw hams were divided into two groups: 1) the 10 left legs of each hog were desalted (D); 2) the 10 right legs were not desalted (N). Following this, both groups of legs were subjected to continuous processing. Samples for chemical analysis and counting of white spots were taken from the 20 legs (10 N and 10 D) from 10 hogs, each weighing 12 to 15 kg. Chemical analysis of muscle tissue showed a highly significant difference (P<0.0001) in the salt quantity in the N (6.85%) and D (5.31%) dry-cured hams, as expected. Desalting affected the level of calcium which was higher (P=0.0124) in the D hams (0.27 g) than in the N hams (0.22 g). Desalting did not affect the free amino acid content, with the exception of methionine which was lower (P=0.0041) in D (0.14 g) than in N hams (0.17 g). Desalting affected the level of two free fatty acids as follows: heptadecanoic acid was higher (P=0.0203) in N (0.18%) than in D hams (0.24%) and DPA was higher (P=0.0373) in N (0.49%) than in D hams (0.39%). By counting the white precipitates, it was established that the regularity of appearance of the precipitate was noted on both the D and N hams, such that where there was no precipitate on the right N ham, nor was their any on the left D ham of the same hog. However, desalting only lead to a slight decrease in the appearance of precipitates (average of 0.7 points), but it is certain that desalting reduces the salt content in the legs, which affects some physical-chemical changes in the ham tissues during processing.

EFFECT OF TG AND DGAT1 POLYMORPHISMS ON BEEF CARCASS TRAITS AND FATTY ACID PROFILE

The objectives of this study were to determine allele frequency and genotype count of thyroglobulin (TG) and diacylglycerol-0- acyltransferase-1 (DGAT1), genes encoding the TG and DGAT1 enzymes, and to determine the effect of the TG and DGAT1 polymorphisms on fatty acid profile in beef carcass. All genotypes were determined by PC-RFLP assay. The polymorphism of TG and DGAT1 had no significant influence on the total lipid content, backfat thickness, EUROP and carcass conformation score. The TT genotype of TG gene resulted in a lower total lipid content and backfat thickness, while KK genotype of DGAT1 gene showed a greater total lipid content and backfat thickness. The content of the majority fatty acids in MLD and subcutaneous fat tissue was not significantly affected by the TG and DGAT1 polymorphisms. The results confirm the lack of an association found by other studies. Further research should be carried out to validate the initial observation.

Veal fatty acid composition of different breeds

Abstract Veal fatty acid composition in M. Longissimus thoracis was investigated in different calf breeds (Simmental, Holstein, Simmental x Holstein). Calves were reared on the same farm under identical feeding and handling conditions. Simmental calves had higher polyunsaturated fatty acid (PUFA) but lower saturated fatty acid (SFA) and monounsaturated fatty acid (MUFA) values than Holstein and crossbreed calves (P<0,05). The PUFA/SFA ratio was the highest in Simmental calves and the lowest in Holstein calves. Simmental calves also had the highest n-6/n-3 ratio while the crossbreed calves had the lowest n-6/n-3 ratio.

Sensory profiling of Dalmatian dry-cured ham under different temperature conditions

Abstract To investigate the influence of the Dalmatian ham processing conditions on weight loss and sensory characteristics, 20 hams were processed following different temperature conditions during salting and ripening. For that purpose, hams were evaluated using quantitative descriptive analysis. The weight loss was higher and all sensory traits except presence of tyrosine and phenylalanine crystals were higher rated for hams processed at higher temperatures. The most significant (P<0.0001) influence of temperature was established on subcutaneous fat color, muscle color and presence of tyrosine and phenylalanine, whereas no influence was established on appearance, marbling, flavor and melting. This concludes that there is overall significant effect of higher temperature on sensory characteristics most likely due to the more intense proteolysis and lipolysis.

Characteristics of calves rearing in northern Croatia

The aim of this study was to investigate characteristics of calves rearing technologies at family farms in northern Croatia (Varazdin and Medjumurje County). Calves up to eight weeks of age at family farms in Varazdin County were kept mostly tied (57.7%). After eight weeks of age, calves in both analysed Counties are dominantly kept tied. First colostrums ration was given to calves within first three hours after calving, i.e. on 99.2% of analysed farms in Varazdin County and 90% of analysed farms in Medjimurje County. On the majority of farms colostrums is given to the calves in amount of 1-1.5 litres (51.9% Varazdin, i.e. 65% Medjimurje County). Freezing of colostrum is done at 10.5% of analysed farms in Varazdin and 15% of analysed farms in Medjimurje County. In Varazdin County farmers feed calves with milk or milk replacer significantly longer (P<0.001) than farmers in Medjimurje County. Consequently, calves in Medjimurje County consumes significantly lower quantities of milk or milk replacer (P<0.001). Calves in the Medjimurje County are significantly earlier fed with solid feed: hay (P<0.05), pre-starter or starter (P<0.001), and water (P<0.001) than on farms at the Varazdin County. Total mixed ratio (TMR) was used neither in Varazdin nor in Medjmurje County in calves’ nutrition, and colostrums quality was checked only at 3% of farms in Varazdin County (4 farms), and only at one farm in Medjimurje County.

Effect of genotype, sex and slaughter weight on veal Longissimus muscle area measured by ultrasound and planimeter

Abstract The aim of this research was to determine effect of genotype (Holstein, Simmental and their crossbreeds), sex and slaughter weight groups (SW1=150-160kg and SW2=190-200kg) on veal Longissimus muscle area (LMA). Between the12th and the13th rib, two ultrasound LMA (ULMA) images were taken from each animal and carcass LMA (CLMA) traced on transparent foil was measured by planimeter. For both measures, Simmental calves had larger LMA than Holstein (P<0.001) and crossbreeds (P<0.05). Male and female calves did not differ significantly in ULMA and CLMA. Calves of SW2 group had larger LMA (P<0.0001) than SW1 group. High correlation coefficient between ULMA and CLMA was determined in this research. Veal LMA was significantly affected by genotype and slaughter weight. According to high correlation coefficients, ultrasound can be useful in estimating carcass traits of cattle at early age.