Nine multiparous cows were biopsied twice – in the first and fifth week after parturition in winter 2004/2005 on the Research and Study farm Vecauce of Latvia University of Agriculture. The aim of the research was to reveal distribution of inflammatory factors and apoptosis in the cow’s endometrium in post parturition period. Haematoxylin and eosin were used for routine staining of each sample. Tumor necrosis factor α (TNFα, w.d. 1:100, Abcam, England), and interleukin 10 (IL10, w.d. 1:400, Abcam, England) were detected immunohistochemically (IMH), and TUNEL method was used for detection of apoptosis. Distribution of these factors and substances was determined semiquantitatively by counting positive structures in visual fields. A significant increase in the total amount of inflammatory cells, as well as in the amount of the TNFα and apoptotic cells in endometrium between the first and fifth week after parturition (p is less than 0.01) was observed. A significant positive correlation (r=0.41; p is less than 0.01) between infiltration of endometrium with neutrophils and with macrophages was detected in the first week after parturition. A mild positive correlation (r=0.52; p is less than 0.01) between neutrophils and lymphocytes, as well as between lymphocytes and macrophages (r=0.35; p is less than 0.01) was found four weeks after parturition. A mild positive correlation (p is less than 0.05) was observed between amount of inflammatory cells and TNFα (r=0.52), and number of apoptotic cells and TNFα (r=0.58). The research suggests that inflammatory factors and apoptosis intensively act during the process of involution in the cows’ endometrium from the first up to the fifth week after parturition. Intensity, amount and activity of these components show individual variations in each case.

The aim of the study was to find out the differences of blood biochemical and morphological parameters in cows with and without retained foetal membranes. Sixty cows of different age of Latvian blackand- white breed from two Joint Stock Companies were used in the research that was divided into two groups: control group of 15 cows, and 45 cows with retained foetal membranes. Research was done from September 2007 to January 2009. In haematological parameters on the second day postpartum, control group cows had increased leukocyte count on the account of mature neutrophils, but in the group of cows with retained foetal membranes leukocytes were within the range of normal values. The difference of the above mentioned parameters between both of the groups was significant (p is less than 0.05). At the same time, in cows of both investigated groups the number of band neutrophils was slightly increased (p is greater than 0.05). Haematological analyses showed leukocytes shift to the left and lymphopenia with a tendency to get normal within six weeks postpartum in both cow groups. On the third week postpartum, in cows with retained foetal membranes the band neutrophil count increased significantly (p is less than 0.05) indicating that the inflammation process has flared up. Blood for biochemical examination was sampled from cows within 48 hours postpartum in order to evaluate the functional condition of liver in milking cows. A significantly higher (p is less than 0.05) total and direct reacting bilirubin was observed in cows with retained foetal membranes, although it was within the range of normal values.

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.

The changes in the serum immunoglobulins concentration were investigated in newborn heifers from birth to 7 days of age. The mothers of calves were determined serum and colostrum immunoglobulins (Ig) concentration. The research was carried out at the Latvia University of Agriculture (LLU), in dairy farm ''Ligotnes'' of the Research and Study Farm ''Vecauce'', in a loose housing system with 530 cows, of which 430 were milking cows. The cows during the dry period were kept tethered in the farm. Eighteen heifers and their dams (Latvian Brown and Holstein breeds) which calved from 30 November 2010 to 23 January 2011 were used in this study. The calves' serum total immunoglobulin concentration at birth was 9.0 ±1.31 mg dLE-1 (or 0.09 mg mLE-1), and after 24 hours (h) it increased significantly to 4.3 mg dLE-1 (or 0.043 mg mLE-1), p is less than 0.05. The immunoglobulin G (IgG) concentration in calf serum after birth was 6.8 ±1.50 mg dLE-1 (or 0.068 mg mLE-1), and after 1 day and after 7 days it did not change significantly. The average Ig serum concentration in cows was 12.6 ± 1.36 mg dLE-1(or 0.126 mg mLE-1), and Ig concentration in colostrum was 18.5 ± 1.68 mg mLE-1. On average, close correlation (r=0.56) was found between cow blood serum IgM and colostrum IgM. Correlation between cow and calf IgG serum concentration proved to be weak (r=0.49).

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.

Neosporosis is an infection disease caused by a single celled parasite Neospora caninum that produces cysts in the host organism. The dogs are a definitive host of parasite; cows and other ruminants are intermediate hosts. It causes neuromuscular disorders in dogs and abortions, birth of weak calves and neonatal mortality in cattle. Disease occurs worldwide (Sweden, Germany, Spain, Australia, Canada, USA et al.). Our aim of this study was to clear up how many seropositive animals in two seropositive dairy herds (after bulk milk investigation) in Latvia there are, their relationship and possible changes of their biochemical data. The studies in 2006 between September and November were carried out. In two farms there were 14 seropositive animals (from 67). There was evidence of inheritance of neosporosis infection. No differences were recognized in cows' blood biochemical data between positive and negative animals.

In automatic milking systems, where the concentrate and forage components of the ration are offered to the cows separately, lack of control over intakes can result in difficulties balancing the forage and concentrate portions of the diet, leading to problems associated with high concentrate intakes and concomitant low forage intakes. In order to check this as a problem on a dairy unit, the feeding behaviour of a sample of cows was observed by video recording. As a pilot study, four Holstein Friesian cows (two at the highest yield and two at the lowest yield of the milk production range) were selected from sixty lactating cows on the Estonian University of Life Sciences’ farm near Tartu, Estonia. The study took place from May 18th till November 4th 2014. The cows were robot-milked and fed a ration comprising, separately, concentrate feed from a robot and a feeder, and a grass/clover silage mix forage at the feed barrier. With the low number of samples the results are indicative and descriptive, but it appears from the raw data that individual variation in visiting times and times spent at the feed barrier are greater than the effect of level of production. Cows spent a significant portion of their time idling at the feed barrier, not actively feeding. It is concluded that care should be taken to presume behaviour from positional data, and there is no evidence that cows with higher and lower milk yields are differentially motivated to feed from a forage source.