Jelena Ramljak

Conservation priorities of genetic diversity in domesticated metapopulations: a study in taurine cattle breeds

We estimated neutral diversity of 21 European cattle breeds with 105 microsatellites. Nine of them resembled unselected Balkan Buša strains with diffuse breeding barriers and the 12 others were strongly differentiated, isolated breeds. Because of the impact of neutral genetic diversity on long-term population adaptive capacity, we discuss the long-term outcome of different conservation priorities in a subdivided metapopulation of the investigated cattle breeds. The optimal contribution to a pool of total genetic diversity allocated more than 95% of long-term relevant neutral diversity to virtually unselected strains of the Balkan Buša, while the maximization of total variance preferred inbred breeds. Current artificial selection methods, such as genomic selection sped up and a recovery of underestimated traits becomes quickly impossible. We emphasize that currently neutral and even deleterious alleles might be required for future genotypes in sustainable and efficient livestock breeding and production systems of a 21st century. We provide cumulative evidences that long-term survival relies on genetic complexity and complexity relies on allelic diversity. Our results suggest that virtually unselected, nonuniform strains harbor a crucial proportion of neutral diversity and should be conserved with high global priority. As one example, we suggest a cooperative maintenance of the nondifferentiated, highly fragmented, and fast vanishing metapopulation of Balkan Buša.

Analysis of genetic and cultural conservation value of three indigenous Croatian cattle breeds in a local and global context

It is widely accepted that autochthonous cattle breeds can be important genetic resources for unforeseeable environmental conditions in the future. Apart from that, they often represent local culture and tradition and thus assist in the awareness of ethnic identity of a country. In Croatia, there are only three indigenous cattle breeds, Croatian Buša, Slavonian Syrmian Podolian and Istrian Cattle. All of them are threatened but specialized in a particular habitat and production system. We analysed 93 microsatellites in 51 animals of each breed to get thorough information about genetic diversity and population structure. We further set them within an existing frame of additional 16 breeds that have been genotyped for the same marker set and cover a geographical area from the domestication centre near Anatolia, through the Balkan and alpine regions, to the north-west of Europe. The cultural value was evaluated regarding the role in landscape, gastronomy, folklore and handicraft. The overall results recognize Croatian Buša being partly admixed but harbouring an enormous genetic diversity comparable with other traditional unselected Buša breeds in the Anatolian and Balkan areas. The Podolian cattle showed the lowest genetic diversity at the highest genetic distance to all remaining breeds but are playing an important role as part of the cultural landscape and thus contribute to the tourist industry. The genetic diversity of the Istrian cattle was found in the middle range of this study. It is already included in the tourist industry as a local food speciality. Current and future conservation strategies are discussed.

The genetic diversity and structure of 18 sheep breeds exposed to isolation and selection

The phylogenetic layout of the genotyped (30 microsatellite) 18 sheep breeds in this study demands and provides the opportunity to evaluate both neutral and adaptive components of genetic diversity in a naturally and artificially selected and subdivided sheep population. Seven Pramenka strains from Bosnia and Herzegovina and Croatia characterized by a very low intensity of artificial selection, preserved the highest neutral genetic variability. Eight central and north-western European breeds under considerable artificial isolation and selection preserved the lowest genetic variability. Only combinations of various phylogenetic parameters offer a reasonable explanation for underlying evolutionary forces working in the investigated island and mainland sheep breeds under variable natural and artificial selection. More than 60% of total genetic, diversity was allocated to virtually unselected Pramenka strains, and an additional 25% to native moderately selected Graue Gehoernte Heidschnucke and intensively selected Ostfriesische Milchschafe. Some economically very important breeds and strains did not contribute to a pool with maximal genetic diversity, while they play an important role in the cultural heritage of respective countries.

Genetic diversity measures of the Croatian Spotted goat.

In the present study, microsatellite data of 20 loci were generated and utilized to evaluate genetic variability of the Croatian Spotted goat. Genetic variability was high, with means for expected gene diversity of 0.771, observed heterozygosity of 0.759, and 8.1 for the total number of alleles per locus. There are no indications for deviations from random breeding within the population. Level of inbreeding was only 2% and non-significant. The population was found to deviate significantly under infinitive allele model (IAM) and two phase model (TPM), while stepwise mutation model (SMM) and qualitative mode-shift test of allele frequencies indicate the absence of genetic bottleneck in the recent past in the population of the Croatian Spotted goat. High level of genetic diversity, as it is presented in this study, may be seen as an initial guide for conservation decisions in the future.

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.

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.

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.