The aim of the work is to investigate raw milk from different bulls' daughters to clear up the influence of cows' genetic predisposition to milk microbial contamination and somatic cell count (SCC). Particular attention is paid to develop productive cow milk yield, milk fat, milk protein and in recent years, the SCC heredity. The literature describes a variety of lines and families, representatives of the resistance to certain diseases (leucosis, mastitis, tuberculosis, brucellosis, foot disease), it shows the determination of a genetic factor for this trait. If the selection results show increased resistance to a disease, then this indicates a genetic disease resistance and shy. The paper focuses on microbial contamination of raw milk at 7 different studies of bull daughters in the same line for housing, feeding and conditions of use. Raw milk samples were obtained from the breed Latvian brown (LB) from dairy cows shed of cattle shed Saujas, which belongs to SIA Palsa and is located in the civil parish Varini, Smiltene county in the year 2008/2009. Compared between the lines of bulls' daughter milk yield of the sample average value of the uniformity of variance analysis shows that they significantly differ (F=2.452, p=0.039). Comparing each line of bulls' daughters SCC of the sample average value of the uniformity of variance analysis showed that the SCC was statistically significantly different (F=2.083, p=0.075) of the various lines of bulls daughters.

Genotypes of CSN3 gene were detected in 71 individuals of Latvian Blue breed and in 30 individuals of Latvian Brown breed using a PCR-RFLP method. Animals were chosen at random from each heard. This study investigated the alleles A and B of CSN3 gene, while determining the allele and genotype frequencies and Hardy-Weinberg equilibrium proportions in both populations. The results showed that in our analyzed samples from 71 Latvian Blue breed only 7 animals (10%) had the genotype BB, and in analyzed samples from 30 Latvian Brown breed only 3 had the genotype BB (10%). Frequencies of CSN3 genotypes AA, AB, and BB correspond to Hardy-Weinberg equilibrium proportions and populations in genetic equilibrium. A wide variation in the B allele frequency among Latvian Blue and Latvian Brown breeds was found suggesting that molecular selection for animals carrying the allele B of CSN3 could impact breeding programs for dairy production in Latvia.

One of most important traits in dairy farming is cow (Bos primigenius taurus) longevity. In last few years the length of productive life in Latvian dairy cow population significantly decreased. Cow longevity depends on a large amount of genetic and non-genetic factors. Data from 1037 excluded Latvian brown (LB) breed cows were included in the analysis. Cows were born in the period from the year 2002 to 2006 and a farm size was 9 – 163 cows per farm. Farms were dislocated in all main regions of Latvia. Average life length of cows excluded from the herd was 2463.0 days in small farms, 2234.6 days in medium size farms and 2089.5 days in large farms. Cows’ productivity in one life day in small farms was 5.9 kg energy corrected milk (ECM), in medium size farms 6.2 kg ECM and in large farms 6.5 kg ECM. Large farm cows had longer life length in days (p is less than 0.05), but higher productivity in one productive day (p is less than 0.05) and productivity in one life day.

In breeding of Latvian Warmblood breed carriage type horses Equus caballus one of major breeding objectives is producing of typical purebred animals with minimal influence of modern warmblood breeds. The aim of the study was to analyze the quality of Latvian Warmblood horse breed carriage and sport type mares included in the register of Latvian Horse Breeding Association broodmares and differences between types in valuation and quality of progeny. The data included 135 records from Latvian Warmblood horse breed mares having valuation both of conformation and performance. The data from 79 sport type and 56 carriage type broodmares were collected. The majority of mares in population (31.9%) had proportion 0 – 24.9% of Latvian warmblood purebred ancestors. The proportion of Latvian Warmblood purebred ancestors in the group of carriage type mares was high – 72.2%, while sport type mares – only 23.4%, a difference between groups was significant (p is less than 0.01). Sport type mares showed significantly (p is less than 0.05) better results in conformation and performance quality whereas carriage type broodmares had significantly higher count of daughters registered in Stud book. Comparison of breed types showed that groups did not differ significantly by height of withers and quality of progeny. Lower quality of conformation and performance of carriage type had to be explained by pedigree data as the main criteria for acceptance, also with older age of broodmares. For future the main goal has to be censorious licensing of best carriage type stallions and using young broodmares with higher quality of gaits and conformation for breeding purpose.

The aim of the present research was to evaluate the affect of genetic and environmental factors on the variability of the goat milk yield, fat and protein content in goat milk in Latvia. Data of 6067 lactation records from 2400 goats of six different breeds were analysed in the period of 2001 to 2010. The highest milk yield (662.7±14.58 kg) was obtained in 2002, the highest fat content (40.7±0.05 g kgE-1) – in 2004, but highest protein content (32.7±0.19 g kgE-1) – in 2008 (p is less than 0.05). Basically there are two goat breeds in Latvia: Latvian goats and Saanen goats. In the research, 3261 Latvian and 2032 Saanen goats in closed lactations were analysed. It was found that Saanen goats gave the highest milk yield (579.3±5.01 kg), but Alpine goats – the highest fat and protein content (respectively 41.7±0.63 and 32.3±0.30 g kgE-1; p is less than 0.05). It was observed that most of all the goats kidded in winter (2379) and spring (3378). The highest milk yield (583.8±7.39 kg) was determined for goats kidded in winter season, but the highest fat content (41.8±0.06) and protein content (32.3±0.03) – for goats kidded in summer season. The average milk yield in the first lactation (1636) was significantly lower than in the third lactation (578.0±8.34; p is less than 0.05) when the goats produced the highest milk yield in the research.

The aim of our study was to determine up to what extent the number of services per calving (NSPC) affects dairy cow productive and reproductive performance. The study contains data from the Agricultural Data Centre of Latvia about 26888 Latvian Brown (LB) and Holstein Black and White (HBW) breed cows that were born from year 2005 – 2010, closed at least 5 full lactations and were culled from herds. In data set we have included data about cow milk productivity (calculated in ECM), longevity traits and reproduction traits. The reproduction traits included the number of services per conception (NSPC), calving interval (CI) and calving to conception interval (CCI) in the first five lactations. The average lifespan of LB and HBW dairy cows was 3149.5 days and in this period 39570.6 kg ECM were obtained. LB breed cows were characterized by 23.5 days longer lifespan and by 6035.4 kg ECM lower lifetime milk productivity than HBW breed cows, but they showed higher reproduction trait scores than LB breed group. HBW cows had a significantly (p is less than 0.05) higher NSPC, CCI, number of milking days (MD) and CI than LB breed cows in all five analysed lactations. The NSPC in the first lactation increased the calving age at the fifth lactation – cows with NSPC in the first lactation is greater than 4, fifth time calved 170.7 days in LB breed group and 190.8 days in HBW breed group later than cows with one NSPC in the first lactation.

Milk yield, composition and milk coagulation properties can be affected by kappa-casein (κ-CN) and beta-lactoglobulin (β-LG) genotypes and breed. Latvian Brown (LB) and Latvian Blue (LZ) are local dairy breeds in Latvia. These breeds are not so high-yielding than other commercial dairy breeds, besides, the number of those animals decrease each year. The aim of the research was to analyse the influence of κ-CN, β-LG and breed on milk composition and milk coagulation properties. Data were collected from 56 Latvian Brown and 26 Latvian Blue in 2016. Widespread κ-CN genotype was AA (0.593) in LB breed and AB (0.636) in LZ breed, while β-LG highest frequency was BB genotype. Significant effect was not observed on milk yield; however the highest daily milk yield was from AB κ-CN genotype (19.7 ± 1.52 kg) in LB breed. Significant differences were observed in fat content – the highest fat content accordingly κ-CN was from AA genotype in LB (46.3 ± 1.89 g kgE-1) and 45.5 ± 1.37 g kgE-1 from BB β-LG genotype in LB breed (p is less than 0.05). A lower protein content was observed from AA κ-CN genotype in LZ breed (33.8 ± 1.30 g kgE-1), while highest from BB genotype in both breeds. Curd firmness was not significantly different by genotypes and breed. Significantly shorter milk renneting time of β-LG was obtained from LB breed (14.6 ± 2.76 min, p is less than 0.05), while κ-CN genotype was not significantly affected.

The objective of the study was to analyze measurements of the sires used in Latvian Warmblood (LWB) and Latvian Heavy Warmblood (LHWB) breeding programs in the period 2003 – 2017, two major horse populations in Latvia included in one studbook. The Latvian Warmblood has an open studbook for breeding sport horses, whereas the Latvian Heavy Warmblood is a partly closed studbook. Measuring information for all sires with at least one foal born (n=834) in the respective time period was retrieved from the Latvian horse database, with 673 stallions measured at least once. The data consisted of direct measurements – height at withers, chest circumference and cannon bone circumference – and two calculated indices – massivity index and boniness index. Average values of adult stallions were analyzed in four groups – LWB, LHWB, ‘other warmbloods’ and refining breeds, with LWB and ‘other warmbloods’ showing similar average values. Sires were divided by use in breeding into 3-year periods to observe a possible change in the breeding objective and stallion choice, however, no significant differences were found in LWB or LHWB. Average measurements of stallions used in the LWB breeding program (different breeds) were 168.6 ± 4.3 cm for height at withers, 194.4 ± 6.6 cm for chest circumference, 21.8 ± 1.0 cm for cannon bone circumference, massivity index 115.5 ± 3.1, boniness index 13.0 ± 0.5. Average measurements of stallions used in the LHWB breeding program (only LHWB stallions) were 167.6 ± 4.6 cm, 201.4 ± 7.3 cm, 23.7 ± 1.0 cm, respectively, and massivity index 120.0 ± 5.0, boniness index 14.1 ± 0.6. Significant differences between LWB and LHWB stallions were observed in all parameters, except height at withers, and between measurements at the age of 2, 3, 4 years and adult (5 and more years).

The aim of our study was to describe the histopathological and cytological characteristic of the cow endometrium on the seventh day of the oestrous cycle. In this study, 11 different breeds’ dairy cows (78.18 ± 37.46 months old, in 3.6 ± 2.17 lactation, the mean body condition score 3.4 ± 0.72 (5 points scale)) from Research and Study farm ‘Vecauce’ were selected. All cows were more than 210 days postpartum. Overall health and reproductive tract examination was performed, progesterone (P4) and estradiol (E2) concentration in blood serum were established and the biopsy and cytology samples of endometrium were taken. Mean E2 concentration was 14.92 ± 7.92 pg mLE−1, mean P4 concentration was 13.64 ± 9.44 nmol LE−1. The mean percentage in the cytology slides was established: epithelial cells 89 ± 9%, polimorphonuclear leukocytes (PMN) 6 ± 5%. Cytological subclinical endometritis (SE) was confirmed in 5 cows. Histopathological findings (out of 22 samples): endometrium stromal edema in 14, hemosiderin and hemosiderophages in 8, supranuclear vacuolization in 12, pseudodecidual reaction in 12 samples. No subnuclear vacuolization and mitosis in the glandular epithelium were detected. Histopathological examination did not reveal SE. Morphology between the uterine horns with and without corpus luteum (CL) and between cows with serum P4 level higher than 15 nmol LE−1 and lower than 15 nmol LE−1 were not statistically different (p is greater than 0.05). In conclusion, histopatological examination is more reliable diagnostic method for SE. Future investigation should be performed to establish cut-off values for the diagnosis of SE in cows more than 210 days postpartum.

The preservation of local animal breeds is a topical theme in recent years. Latvian Brown (LB) and Latvian Blue (LZ) cow breeds are exhausting and must be preserved. It can be performed by the use of multiple ovulation and embryo transfer (MOET). The difficulties exist in choosing the gene-fond (GF) cows as donors caused by the small number of animals. Twenty-three cows were intended for donor cow’s role from different herds until September 2018, and twenty of them were accepted. Anamnesis, clinical examination, blood morphology (13 parameters) and biochemical indices (19 parameters) were analysed before MO induction. Three cows were rejected because of ovarian cysts or pyometra, negative energy balance (NEB) (glucose is less than 2.3 mmol LE−1 simultaneously with elevated ß-hydroxybutyric acid is greater than 1.4 mmol LE−1) and elevated (p is less than 0.05) number of leukocytes (28.20 x109 LE−1). More than 52.6% of cows had a repeated artificial insemination before the last parturition, and 5.3% of cows had lifeless offspring in the last parturition. The 1st and 2nd lactation cows were healthier than older cows (p is less than 0.05). The amount of albumins, cholesterol, triglycerides and Na, K, P, Cl, Mg was significantly different in donors with and without successfully obtained embryos (p is less than 0.05). In conclusion, not only acceptable clinical health but also the cow metabolic status is a decisive factor for success of MOET.