In order to address existing and foreseen climate change and environmental challenges, the European Commission has adopted a set of proposals as part of the European Green Deal to reduce emissions of greenhouse gases and become the first climate-neutral continent in the world. In the energy sector it is planned to implement specific actions to increase the contribution from renewable sources of energy. Livestock manure as a renewable resource can be processed to produce biogas through anaerobic digestion processes. This study aimed to estimate the amount of livestock manure potentially available for biogas production in Latvia based on statistical information on the number of animals representing current and past trends, and forecasts for the future provided by the results of the Latvian Agricultural Sector Analysis Model (LASAM). The results of this study showed that the share of livestock manure processed to produce biogas has increased considerably during the time period from 2010 to 2019 in all groups of livestock considered for this application in Latvia. However, there are still opportunities to increase the share of manure utilised for anaerobic digestion, especially in the livestock groups of dairy cows and non-dairy cows, as only 16% and 13% of the available amount of manure was processed in 2019, respectively. The LASAM results indicate that the number of animals will experience negligible changes or will decrease; therefore, more attention will need to be paid to increase the efficiency of processing the existing amount of manure rather than relying on an additional amount of manure available for biogas production.

Q fever is a widespread disease affecting reproduction in dairy cattle. Several risk factors can increase the possibility of the herd becoming infected and the persistence of infection. The aim of this study was to characterise the dynamics of C. burnetii infection in affected herds and to evaluate reproduction problems and risk factors using a questionnaire within infected and infection-free dairy herds. In total, 25 farms that were serologically positive or shedding C. burnetii DNA in milk and 14 C. burnetii infection-free farms in Latvia answered the questionnaire. Ten positive herds were studied by testing individual blood and milk samples from up to 10 animals at two times separated by 7.5 to 13 months. The number of serologically positive and suspicious animals was higher in the second sampling even though several animals were culled. In the positive herds, the percentage of dystocia, stillborn calves and abortions during the last year was significantly (p=0.001; 0.01; 0.005, respectively) higher than in the negative herds. Several significant factors were found for the presence of Q fever infection, such as the herd size, the regional population density of ruminants, artificial ventilation systems, and frequent farm visitors. Deratisation was less practised in the negative farms and the presence of ticks was observed more often in the negative farms. Only two identified risk factors can be mitigated – the ventilation system and frequent farm visitors. The other factors cannot be changed arbitrarily but they have to be taken into account by decision makers.