In their review, the authors present the results of research evaluating the effect of fermented liquid feed on the performance and digestive health of weaned piglets and fattening pigs. Based on the available literature, it is advisable to carry out controlled fermentation instead of spontaneous fermentation, because by inoculating the feed / raw materials with specific lactic acid bacteria, the fermentation process goes in the right direction, lower pH values can be achieved within the same timeframe, which all help to control the acid-sensitive pathogenic microbes. The fermentation of only certain raw materials, as opposed to a complete diet, has the advantage of better controllability, and the incorporation of these fermented end products into final diets provides farms with increased flexibility. During fermentation, the particle size of the feed / raw materials and the levels of antinutritive substances are reduced, thereby increasing their digestibility. Feeding studies have shown that improvement in nutrient utilization is primarily due to better bioavailability of nutrients, as opposed to increased feed intake. Several works have demon-strated that fermented liquid feeds significantly reduce the pH of gastric juice, Salmonella spp. levels and the chance of developing diarrhoea caused by coliforms in piglets. Fermented feeds support gut health, thus also playing an immunomod-ulatory role. Taking all this into account, the authors believe that fermented liquid feeds in nutrition of pigs may be an effective alternative after the antibiotic reduction provisions come into force in the European Union in 2022.

Background: The barn swallow (Hirundo rustica) is a migratory bird with a characteristic color, shiny black on the back, dirty white feathers on the belly, rust-red throat, weighing 17–20 g. This species mainly hunts flying insects, catching them in flight and the swallows are constantly hunting in the air between sunrise and sunset. As the food-scarce autumn season approaches, swallows gather in large flocks and when the daytime temperature drops permanently below 15 ºC, they leave for their wintering grounds in Africa. The birds are preparing for the migration, replenishing their body's fat depots. By the time of leaving, thebirds reach a body weight of 22–25 g, which enables them to travel thousands of kilometers. The metabolism of birds is fast, which is especially noticeable in smaller species. Shortterm starvation is already associated with a significant deterioration in nutritional status. Objectives: The carcasses of the swallows that were still alive at the time of capture, but died during transport were examined to identify to cause of sudden death. Materials and Methods: On September 16, 2024, 34 immobile and flightless swallows were delivered to the Clinic of the Department of Exotic Animal and Wildlife Medicine from the beach in Csopak, Hungary (46° 58′ 10.4″ N, 17° 56′ 13.9″ E). Five randomly selected carcasses of swallows were examined according to the standard pathological methods (dissection, histopathology, special stainings, bacteriological examination, PCR). Results and Discussion: During the dissection the body weight of the swallows delivered to the clinic was 12.0–13.0 g (12.6 g on average) which is around half of the normal bodyweight of these birds before migration. The supplementary examinations were negative for known pathogens and histopathology showed extreme lack of glycogen. According to the weather data from 11th of September 2024, a cyclone with significant cooling and heavy rainfall hit Hungary. The reason behind the death of the swallows was starvation caused by the sudden disappearance of the population of flying insects that could be caught by swallows due to cold and rainy weather. This case draws attention to the dangers of sudden extreme effects of global climate change in the case of some sensitive animal populations.