I n the past two decades many substances of natural or synthetic origin were studied as potential alternatives to antibiotic growth promoters (AGP) and some of them, particularly immunomodulators (IMs) and nutraceuticals (NCs), have shown to be capable of stimulating functions of the immune system and improving general health. At the same time, they were shown to be harmless for animals and the environment. Promising results have been obtained with natural clay minerals, zeolites among which clinoptilolite (CPL) is the best known as zootechnical and biomedical feed ingredient widely reported in scientific literature and used in farm animal nutrition. CPL has a potential to replace AGP due to its unique anti-bacterial properties, safety and efficacy as dietary supplement in food animals unifying potentials of an IM and NC. Currently, there INTRODUCTIONT he phrase "survival of the fittest" as an alternative to "natural selection" has been adopted and published in 1868 by Charles Darwin (1), and nowadays is becoming so true because of the rapid emergence of antibiotic resistant strains of pathogenic microbes of biomedical, particularly veterinary importance. This is a consequence of non-clinical use and misuse of dietary antibiotics for more than sixty years to prevent bacterial infections and to enhance performance in livestock production, mostly in chickens and pigs (2). Namely, the increased sanitary problems in intensive farming of food animals have been overcome thus far by adding sub-therapeutic doses of antibiotic growth promoters (AGP) infeed to enhance production efficiency by increasing growth rate, improv- ing feed utilization and reducing mortality from clinical disease is well documented particularly in swine production systems (3). However, the consumers especially in developed countries are becoming increasingly concerned about drug residues in meat and other animal products (4). In addition, it has been suggested that the continuous use of antibiotics may contribute to a reservoir of drugresistant bacteria (5) which may be capable of transferring their resistance to pathogenic bacteria in both animals and humans (6). As a result, many countries have banned or are banning the inclusion of antibiotics in diets as a routine means of growth promotion. The first experience of an AGP ban in Sweden in 1986 indicated a reduction in growth and an increase in morbidity and mortality rates in weaned pigs, which emphasized the importance of antibiotic use in intensive swine production(7). The total ban of dietary AGP in the EU countries since January 1, 2006 (EU Regulation No. 1831 and the elimination of their use in animal feed and water in the USA effective January 1, 2017 (FDA, CVM 2012, VFD Basics 2017) has had a serious influence on both health and performance of food animals underlining the need to develop alternative dietary and non-dietary strategies to evaluate the potential antimicrobial agents for their replacement (8). According to the World Health Organization, most antibiotics will not ...

The objectives of this study were to examine the influence of body condition of cows on metabolic and antioxidative status, as well as to investigate the relationship between metabolic indicators of lipid mobilization and oxidative stress during transition period. The study was conducted on 24 Holstein-Friesian dairy cows divided into 2 groups according to their body condition score (BCS) as optimal (n = 12; BCS from 3.25 to 3.75) or adipose (n = 12; BCS ≥4). Metabolic status (glucose, triglycerides, total cholesterol, HDL cholesterol, NEFA and BHB), paraoxonase-1 (PON1) and apolipoprotein A-I (ApoA-I) were analysed in sera taken on days -30, -10, -2, 0, 5, 12, 19, 26 and 60 relative to parturition. Adipose cows had significantly higher glucose concentration at parturition being significantly decreased after parturition on days 12 and 19. Total cholesterol and HDL-C concentrations were the lowest at parturition and significantly higher on days 26 and 60 after parturition in both groups of cows. Both investigated groups had significantly higher NEFA concentration from parturition until day 19 after parturition, indicating energy deficit and an increased lipid mobilization after calving. There were no significant differences in BHB concentration during transition period in both groups. No significant differences were found in PON1 activity and ApoA-I concentration during transition period in both groups of cows. However, in adipose cows, although not significantly different, PON1 was decreased from calving until day 19 after parturition indicating a disturbance in antioxidative status in adipose cows. PON1 significantly positively correlated with total cholesterol and HDL-C concentrations and negatively with NEFA indicating a strong relationship of PON1 with lipid metabolism. Significant positive correlation between NEFA and BHB in both groups of cows points out on energy deficit during transition period that cows tend to overcome by lipid mobilization providing alternative source of energy needed for parturition and lactation.

The metabolism of proteins in the blood serum in Boer and Saanen goats was investigated during puerperium. Twenty Boer goats (10 primiparous and 10 pluriparous) and 10 Saanen goats (five primiparous and five pluriparous) between 2 and 5 years of age were used in this research. Blood for analysis was taken every fourth day from day 3 until day 40 post-partum. Blood samples were collected by jugular puncture. In the obtained blood serum, the concentration of total proteins (PT) and albumin (ALB), and the activity of enzymes aspartate aminotransferase (AST) [the Enzyme Commission number (EC number) 2. 6. 1. 1.], gamma-glutamyltransferase (GGT) (EC 2. 3. 2. 2.), creatine kinase (CK) (EC 2. 7. 3. 2.) and alkaline phosphatase (AP) (EC 3. 1. 3. 1.) were determined by spectrophotometry. These parameters were in physiological ranges in Boer goats and in Saanen goats, without significant differences according to number of kids per doe. According to the research results of the blood serum in goats during puerperium, there were no significant differences in the concentration of ALB. Boer goats had significant higher (p < 0.05) concentration of PT and enzyme activity of AP, CK and GGT. Saanen goats had only enzyme activity of AST significantly higher (p < 0.05). Enzyme activity of alkaline phosphatase was significant higher (p < 0.05) in pluriparous goats in both breeds than in primiparous. The obtained results may represent a contribution to a better understanding of protein metabolism during puerperium in dairy and meat goats and for diagnostic purposes.

Svaki kirurški zahvat narušava homeostazu organizma, koja se očituje u imunološkim, neuroendokrinim i metaboličkim promjenama u organizmu. Pretpostavlja se da jačina odgovora organizma ovisi i o jačini traume tijekom operativnih zahvata. Cilj istraživanja je bio utvrditi antioksidacijski status kuja prije i poslije ovarijektomije. U istraživanje je bilo uključeno petnaest kuja pacijenata Klinike za porodništvo i reprodukciju Veterinarskog fakulteta u Zagrebu u kojih je učinjena elektivna ovarijektomija u svrhu kastracije. Kujama je krv vađena prije operacije te poslije prvog, trećeg i sedmog postoperativnog dana kako bi se izmjerio ukupni antioksidacijski status. Svim kujama je učinjena i kompletna krvna slika, biokemija i C-reaktivni protein (CRP). Ukupan antioksidacijski status određivan je pomoću TAS test kitova. Proizvođač kitova preporučuje svakom laboratoriju standardiziranje referentnih vrijednosti. Zbog toga je učinjena analiza 30 seruma zdravih kuja koje nisu bile operirane te je kao referentna vrijednost korištena njihova srednja vrijednost +/- dvije standardne devijacije. Prosječna referentna vrijednost iznosila je 1,55 mmol/L. Vrijednosti ukupnog antioksidacijskog statusa nakon operacije u svim promatranim razdobljima nisu se statistički znatnije razlikovale. Uspoređujući minimalne i maksimalne vrijednosti u svim promatranim razdobljima, zaključili smo da nije bilo velikih razlika u vrijednostima ukupnog antiosksidacijskog statusa u operiranih kuja. Na temelju naših rezultata možemo zaključiti da ovarijektomija nije prouzročila oksidacijski stres.

Background and Purpose: Yeast derivative mannan oligosaccharide (MOS) and zeolite clinoptilolite (CPL) well known nutritional supplements acting as either prebiotic or immunobiotic, respectively, in animal husbandry. The aim of this study was to investigate whether or not these agents referred to as potential alternatives to antibiotics may positively influence systemic immune parameters of weaned pigs without negatively affecting their hematological, serum biochemical and gut histological homeostasis. Materials and Methods: Sixty pigs from a commercial farm were divided into three groups comprising 20 pigs each and treated at 4 weeks of age as follows: controls received standard weaner diet, whereas diet for principals was supplemented with 0.2% of MOS or 0.5% of CPL. The experiment was conducted throughout 35 days and at either Conclusions: MOS did not affect any of monitored parameters, and CPL only sporadically induced lymphopaenia and granulocytosis, decrease of CK and total proteins and increase of urea and creatinine levels, indicating that the agents were not associated with any harmful side effects on monitored blood and gut parameters and impairment in general health status of pigs. INTRODUCTIONT he EU ban on in-feed antibiotic growth promoters (AGP) in swine production has stimulated research for alternative strategies on weaning diets as a way of reducing postweaning gut infections of bacterial etiology and growth retardation as well as of modulating immune functions in order to increase the resistance of pigs to enteric diseases. [3][4][5][6][7][8][9][10][11][12]. However, the results obtained with majority of these substances remained inconclusive as the final aim of using such in-feed supplements is to promote pig immunity, health and performance. Among those few which have shown to be effective in zootechnology and biomedicine are: (a) a variety of polysaccharides from different natural sources, such as yeast derivatives b-glucans and mannans (3) and (b) natural clay minerals, such as aluminosilicate compounds bentonite, kaolin, diosmectite, attapulgite and zeolite (12). The main source for in-feed supplement currently used in pig nutrition as a natural additive is mannanoligosaccharide (MOS) found in large quantities in yeast cell wall (3, 9), The most promising results to date have been obtained with montmorillonite, smectite, illite, kaolinite, biotic and zeolite clinoptilolite (CPL) for their ability to replace AGP as feed additives and to maintain swine health and performance (7,11). HRVOJE VALPOTIĆ 1 RENATA BARIĆ-RAFAJAmong 140 types of natural zeolites, the best known and the most thoroughly tested for its safety and efficacy as feed additive for animal species of veterinary importance is CPL (13). CPL has shown to be effective as growth-promoting (14), immunostimulating (15) and gut health restoring anti-bacterial (16 ) dietary supplement in pigs. Moreover, CPL is the most widespread compound in the medical market and recently has been approved as feed additive in the EU. The CP...