Goran Kiš

In vitro digestibility of phenolics in grain of maize hybrids

Abstract The aim of this research was to determine the quantity of phenolic compounds in the grain of maize hybrids and their in vitro release in pig small intestine. Six maize hybrids belonging to the FAO maturity groups 200-600 were produced under the same agroclimate conditions. Phenolics were determined using Folin-Ciocalteu colorimetric method as gallic acid equivalents. The enzymatic digestion of phenolics was carried out using in vitro procedure for pigs mimicking digestion in stomach and small intestine. The concentration (mg/100g) of free (100.02-157.29), bound (973.41-1160.86) and total phenolics (1105.82-1293.38) varied (P<0.001) among hybrids. In addition, the digestibility of phenolics significantly differed among tested hybrids (P<0.001) and ranged from 37.09 to 45.46%. Content of phenolics in soluble fraction after digestion was higher (486.23 vs. 128.38 mg/100g) than the content of free phenolics suggesting that some amount of bound phenolics was released in small intestine.

Sheep internal parasites on Rab and Pag

Abstract The purpose of our research was to determine which groups and species of internal parasites endanger the health of sheep on the islands of Rab and Pag. The research was carried out in 10 flocks on both islands taking the fresh dung out of 30% of the total number of sheep in each flock. It was ascertained that the gastrointestinal parasites and protozoa of Eimeria genus are present in most flocks on both islands. The presence of the fluke Dicrocoelium dendriticum was ascertained in considerably larger number of flocks on the island of Rab than on the island of Pag. On the other hand, the presence of parasites of Moniezia and Nematodirus genus was ascertained in larger number of flocks on the island of Pag. In two flocks on Rab parasites of Protostrongylus genus were ascertained while on the island of Pag they were not found in any flock.

Relation between endosperm and in vitro kinetic of starch digestibility in maize hybrids for broiler chickens

Abstract The objective of this study was to determine relationship between endosperm type of maize hybrids produced in Croatia and kinetic of starch digestibility provided by in vitro method. Proportion of endosperm type (horny and floury) were used to classify hybrids into dents or flints maize. Flints had less rapidly digestible starch than dents. Maize hybrid kernel endosperm characteristics could be used for prediction of digestibility kinetics of maize grain.

Estimating grass and grass silage degradation characteristics by in situ and in vitro gas production methods

Abstract Fermentation characteristics of grass and grass silage at different maturities were studied using in situ and in vitro gas production methods. In situ data determined difference between grass and silage. Degradable fraction decreased as grass matured while the undegradable fraction increased. Rate of degradation (kd) was slower for silage than fresh grass. Gas production method (GP) data showed that fermentation of degradable fraction was different between stage of maturity in both grass and silage. Other data did not show any difference with the exception for the rate of GP of soluble and undegradable fraction. The in situ degradation characteristics were estimated from GP characteristics. The degradable and undegradable fractions could be estimated by multiple relationships. Using the three-phases model for gas production kd and fermentable organic matter could be estimated from the same parameters. The only in situ parameter that could not be estimated with GP parameters was the soluble fraction. The GP method and the three phases model provided to be an alternative to the in situ method for animal feed evaluations.