The research was conducted with the aim of studying the possibility of using automatic feeding stations for individual sheep (Ovis aries) feeding. The research was organized in 3 periods, in which 10–13 months old sheep – female only (1st research period), 6–10 months old sheep – female only (2nd research period) and 8–12 months old sheep – female only (3rd research period) were used. Part of the sheep did not visit the feeding station at all. Sequentially, over the research periods the percentage was 13%, 37% and 49%. Upon setting the concentrate daily ration 400 g per sheep, on the average the number of visits to the particular feeding station was 6.1 and 4.7 (sequentially in the 1st and 2nd research period). Upon increasing the concentrate ration amount up to 700 g per day, the average number of feeding station visits was 6.9 (in the 3rd research period). The number of visits to the automatic feeding station was varied (V is greater than 10%). Over the research period live weight of the sheep increased significantly (p ≤ 0.05) for the subgroups of animals which made visits to the feeding station regularly during the entire research period. In all research periods, the average daily concentrate intake (373.5 g in the 1st research period, 333.1 g in the 2nd research period and 581.2 g in the 3rd research period) was 93%, 83% and 83% respectively, of the maximum established feeding standard.

The aim of this study was to determine the influence of Jerusalem artichoke flour feeding on the general health status of calves (Bos Taurus), the animal live weight gain and digestive canal morphological development in the first four months of life, as well as to find out the optimal of three inulin doses. Jerusalem artichoke (Helianthus tuberosus) concentrate produced in Latvia contains the prebiotic – inulin. The study was performed on four groups of animals - a control group of 10 animals and three prebiotic groups, 10 animals in each group. All groups were fed the whole milk, but the PreG6 group animals were fed daily with 6 grams of prebiotic, calves PreG12 group were fed with 12g of prebiotic, but each calf in PreG24 group – 24g of prebiotic per day. CoG control animals did not receive feed supplement. Faecal mass consistence of PreG6, PreG12 groups of animals was more stable within the whole research period than CoG. We found that the control group animal weight gain on the 56th research day is statistically significantly (p is less than 0.05) lower than of those calves that received inulin as a food supplement. The highest growth rates have shown PreG12 and PreG24 group of animals, significantly (p is less than 0.05) being ahead of PreG6 group of calves, the highest average daily live weight gain was observed in PreG24 group (0.95 ± 0.093 kg).

Feeding livestock a balanced diet with a differentiated crude protein (CP) content, depending on the lactation phase, can reduce nitrogen emissions from livestock excrement and urine. A higher content of non-starch polysaccharides in livestock diets improves feed absorption in the livestock body and, consequently, nitrogen is emitted more from protein present in livestock manure than from urea acid present in livestock urine. The aim of the study is to calculate the ammonia emission reduction potential in Latvia by optimizing the feeding of dairy cows and ensuring life longevity, as well as provide justification for ammonia emission reduction in dairy farms. Calculations made by using the NorFor Model for optimization of dairy cow (Bos primigenius f. taurus) diets revealed that compared with lowyielding cows, a higher CP content diet fed to high-yielding cows at the beginning of lactation increased the amount of nitrogen (N) in their excrement and urine by 90–180 g dE−1. Reducing the CP content in the cow diet by an average of 10 g kgE−1 dry matter (DM) during mid-lactation resulted in the same trend. Reducing the CP content in the cow diet during late lactation and the dry period by another 20–30 g kgE−1 of DM, N emissions from excrement and urine significantly decreased. Increasing the lifespan of dairy cows also means reducing ammonia emissions from the farm. By increasing the number of lactations per cow on dairy farm, it is possible to reduce the number of heifers per cow. The total reduction of ammonia emissions in Latvia was calculated based on a long-term projection of a decrease of 0.1 heifer per dairy cow. Ammonia emissions could be reduced by 0.051 kt by decreasing the number of heifers by 12.54 thou. at the planned increase in the lifespan of dairy cows by 2030.

The goal of this study was to investigate the use of body reserves, energy balance and fertility parameters at the beginning of lactation in first-parity cows bred in Estonia.