Renata Relic

Quality nutrition is a fundamental factor in both human and animal health. The quality of animal feed is influenced by all processes from the collection of feed to its administration to animals, as well as by the content of specific substances. Substances present in animal feed can be found in animal products and subsequently enter the human body. Therefore, animals used for food production may be fed only with feed that meets prescribed physical, chemical, and nutritional standards, and must not contain substances potentially harmful to animal health, human health, or the environment. Poor hygiene in animal feed is indicated by the presence of impurities or spoilage. The consequences for cattle consuming contaminated feed vary, ranging from mild and gradual effects such as reduced feed intake and decreased production, to death. This paper discusses the effects of certain harmful factors, as well as inadequate preparation and administration of feed, on the health status, reproduction, production characteristics, and behavior of cattle, as indicators of their well-being.

Among helminth infections of small ruminants in Serbia, nematodes predominate, while trematodes occur at lower prevalence. The most important ruminant flukes in Serbia are Dicrocoelium dendriticum (small fluke) trematodes from the Paramphistomum spp., and Fasciola hepatica (large fluke). Dicrocoelium dendriticum is a common parasite of ruminants but humans can act as accidental definitive hosts. This is most important flukes in small ruminants in Serbia and its prevalence ranges from 12.30% to 78.67%. Paramphistomum is a genus of parasitic flatworms belonging to the digenetic trematodes. In Serbia, P. cervi has been found in sheep, goat and cattle and P. microbothrium has been found in sheep and cattle as well as in deer and red deer. Infection with P. cervi was established in 13.44% of sheep and goat herds and P. microbithrium in 9.48% herds. Fasciolosis is an acute or chronic disease caused by the large fluke Fasciola hepatica. Its prevalence ranges from small ruminants in Serbia are less than 4%. Parasitic infections of sheep and goats caused by trematodes are relatively common in Serbia. Although much less common than gastro-intestinal strongyloid infections, they represent a health and economic problem.

Parasitic infections are constant companions of pig production, regardless of the method of breeding. They are equally found in farm and extensive rearing in all production and age categories of animals.Extensive pig breeding has a long tradition. Although this kind of behavior provides pigs with a much more comfortable life than farming (after all, organic production was developed on its principle), it also has many negative consequences for their health. Pigs are exposed to the risk of outbreaks of infectious and parasitic diseases that can cause large losses in production. Extensive and semi-extensive breeding means that pigs have direct contact with a multitude of transitional hosts of parasites, they are in contact with wild swine, and there is also frequent contamination of the area where they are discharged with the excrement of wild animals. Parasitic infections, along with other infectious diseases, are extremely common in this way of breeding. Infection is most often with biohelminths (Metastrongylus sp, causative agents of verminous gastritis, Macracanthorhynchus hirudinaceus) and zoonotic parasites to which pigs are transitional (Trichinella spiralis, Taenia solium, Ascaris ssum) or parent hosts (Alaria alata). There are also species that are equally present in extensive and farm farming, such as e.g. Trichuris suis, Oesophagostomum sp. or Strongyloideus ransomi.

Parasitic infections are constant companions of pig production, regardless of the method of keeping. Caused by several parasitic species, they threaten the health of animals and cause significant economic losses due to lower growth, reduction in body weight of fattening animals and loss of daily gain, poorer feed conversion, and finally, a problem appears in the slaughterhouse industry in the form of confiscation or conditionally usable meat. During research carried out in the period 1991-2021, the most common occurrence of protozoan infections in weaned piglets is that we found the average presence of protozoa Balantidium coli (95-100%), Cryptosporidium sp (17-32%), Eimeria perminuta (27-31%) ), E. debliecki (3-24%), E. polita (4-9%) and Isospora suis (3-13%). Helminth infections Ascaris suum (39-41%), Oesophagostomum dentatum (6-8%), Strongyloideus ransomi (1-17%) and Trichuris suis (1-7%) were also found. The planned application of parasitological, zootechnical and biosecurity measures is crucial in protecting the health of pigs and the success of production.

Summary: Animals, like humans, act according to physiological patterns of behavior that change in response to various internal and external stimuli. Environmental pollutants represent “negative” stimuli and stressors. Air pollution is among pollution sources that pose the greatest threat to the environment and all living organisms. Exposure to pollutants causes behavioral changes in animals and disruption of organ functions and structures, which are often identical to those of humans working or living under the same conditions as animals (e.g., on a farm or in a city). Aside from a shorter life span and possible premature death, there are some diseases which commonly occur as a result of the exposure. Symptoms indicative of a disease or irritation, such as coughing, lameness, diarrhea, eye discharge and the like, cause the animal to make movements (actions) that are not part of their normal physiological routine and are considered behavioral changes. Behavioral changes are the earliest indicator that the animal is suffering from physical or mental disorders that can negatively affect its health and, in the case of livestock, production results. Various animal species serve as indicators of pollution, and domestic animals, including farm animals, can also serve this purpose. Behavioral changes resulting from exposure to various pollutants include disorientation, problems interacting with humans and other animals, reproductive problems, respiratory, digestive symptoms, etc. This review compiled data from a number of studies on changes in animal behavior after short or long exposure to various environmental pollutants. The focus was on the effects of air pollutants on animals, which are of particular importance to humans as they share living or working space with the animals or breed them for economic interest.

The lifespan of the European hare (Lepus europaeus P.) is affected by a number of negative factors, including pollutants. In this paper, the individual and joint influence of age and habitat (elevation and distance from the thermal power plant - TPP) on pathomorphological findings of hares shot during three hunting seasons was investigated. Pathomorphological changes were found in 95.12% of hares. In hares up to 1 year of age, the changes were predominant in the lungs, and in older hares, in the kidneys. Degenerative changes in kidneys and liver and inflammatory changes in kidneys and lungs were considered important most in discussing the influence of chemical pollution. The proximity of TPP influenced the type of changes in the liver. A significant joint effect of age and elevation on the type of changes in the lungs of adult hares and on the heart of young hares was found. Elevation and distance from TPP had a joint effect on the occurrence of changes in the lungs, intestines, and heart in hares from the field farther from TPP. The results indicate that the hares were highly exposed to chemical pollutants that may affect their immunity, and lifespan.

Intensive broiler chicken production involves different lighting regimes, which affects a natural cycle of secretion of melatonin, a hormone included in multiple physiological processes in a bird's body. This research aimed to determine the effects of dietary melatonin supplementation during the first two weeks of broiler chickens' life, bred under constant 24 h lighting, on their health and some hematological, biochemical, and production parameters. The study lasted 6 weeks. Three hundred and twenty 1-day chickens were divided into two groups (control - C and experimental - M), with four replications and 40 chickens in each replica. In the first two weeks (the first phase of the study), a continuous lighting mode 24L: 0D was applied. Group M was receiving a diet supplemented with 30 mg/kg synthetic melatonin only during the first phase. Group C had a diet without melatonin supplementation throughout the whole study. Melatonin addition had a statistically significant effect (P<0.01) on the mean values of body weight and daily weight gain at the end of the 1st, 2nd, 3rd, 4th, 5th, and 6th week. The chickens of the experimental group have had a significantly higher value of the European Production Efficiency Factor (EPEF) (P<0.05). The results presented in this paper indicate a direct benefit in stress relief in broilers and a value of the organism's antioxidant system promotion, manifested by improved production performance and fattening efficiency.

Since the ban in January 2012 of conventional cages for egg production in the European Union (Council Directive 1999/74/EC), alternative systems such as floor, aviary, free-range, and organic systems have become increasingly common, reaching 50% of housing for hens in 2019. Despite the many advantages associated with non-cage systems, the shift to a housing system where laying hens are kept in larger groups and more complex environments has given rise to new challenges related to management, health, and welfare. This review examines the close relationships between damaging behaviours and health in modern husbandry systems for laying hens. These new housing conditions increase social interactions between animals. In cases of suboptimal rearing and/or housing and management conditions, damaging behaviour or infectious diseases are likely to spread to the whole flock. Additionally, health issues, and therefore stimulation of the immune system, may lead to the development of damaging behaviours, which in turn may result in impaired body conditions, leading to health and welfare issues. This raises the need to monitor both behaviour and health of laying hens in order to intervene as quickly as possible to preserve both the welfare and health of the animals.

Aim of the study: Calf rearing practices vary in different countries and may be affected by many factors. Poor management is related to diseases outbreak and death in calves. This study aimed to analyze practices in calf rearing and the occurrence of common calf diseases on family farms in two European countries and to examine the characteristics of a farmer and his farm as factors that may affect the way of performing practices related to calves’ health.Area of study: Slovenia and Serbia.Material and methods: For collecting data, the same questionnaire-based survey was distributed among cattle farm owners in Slovenia and Serbia.Main results: The following factors showed a significant influence (p<0.05) on certain rearing practices: farm size (on time for checking calves, milk reheating, and providing rehydration fluids to the calf with diarrhea in Slovenia), specialization of the production (on preventive antiparasitic treatments and restriction of drinking water for calves with diarrhea in Slovenia, and the time for checking calves in Serbia), breeder’s age (on colostrum quality checking in Slovenia), and breeder’s education (on time for checking calves and checking colostrum quality in Serbia). The results pointed out the rearing practices to be improved in both countries, Slovenia and Serbia, such as colostrum management and prevention strategies of calf diseases.Research highlights: Characteristics of the farmer and his farm may affect many aspects of calves’ rearing. Continuous education of farmers and appropriate production planning can contribute to better farm productivity and better health and welfare of calves.

The aim of this study was to examine the values of energy and protein status indicators of Holstein Frisian dairy cows in different production periods (20 days before calving, 30th and 90th day of lactation period). The study included 76 clinical healthy cows, which were divided into 2 groups. The first group consisted (n = 38) of pregnant heifers (or cows in first lactation after calving), and the second group (n = 38) consisted of cows calved multiple times (cows from second to fourth lactation). The results indicate that average concentration of glucose, albumins and urea at both groups in all phases of investigation are not significantly different in tested specimens (p>0.05). β-hydroxybutyrate concentration (BHBA) at pregnant individuals in late pregnancy period was statistically lower than 30th and 90th day of lactation, with p<0.05 at first and p<0.01 at second group. Lower values of total proteins at both groups were recorded 20 days before calving relative to lactation period, with statistical signifikante at p<0.01 for the first and p<0.05 for the second group. Heifers’ blood globulin concentration was significantly lower (p<0.05) relative to values determined after calving, during lactation period. Multiparous cows before calving also had lower average values of globulin, but differences were not significant.