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The aim of the study was to investigate the effect of dietary herbal extracts derived from garlic (Allium sativum), rosemary (Rosmarinus officinalis), sage (Salvia officinalis), oregano (Origanum vulgare), nettle (Urtica dioica), purple coneflower (Echinacea purpurea), or thyme (Thymus vulgaris) on the performance indices and oocyst output in broilers experimentally infected with 190 000 oocysts of Eimeria spp. on day 12 of age. A total of 400 one-day-old Ross 308 broiler chicks was randomly allocated into 10 groups with 5 replicates (cages) of 8 chickens per replicate. Two of the groups, one challenged and the other not, were given a basal maize-soyabean meal diet without any additives; one of the challenged groups was administered a basal diet with the coccidiostat diclazuril (1 mg · kg−1) and the remaining birds of the infected groups were given a diet supplemented with one of the tested herbal extracts at a level of 750 mg · kg−1. Throughout the 42 days of the experiment, performance parameters, mortality, oocyst output, and slaughter indices were recorded. Among the tested herbal extracts, in the first rearing period (9 d post infection), only garlic and sage extracts alleviated the negative effect of infection, as shown by the increase in body weight gain to the level recorded in the coccidiostat-supplemented group and, in the case of garlic extract, by lower mortality. In the second and entire experimental period, dietary supplementation with the herbal extracts improved the growth performance of infected chickens to the level obtained in the groups infected and fed the coccidiostat or the uninfected and unsupplemented ones, but there was no positive effect of extracts on oocyst output. It is concluded that the herbal extracts tested in the current study do not prevent coccidiosis induced by high-pathogenic field Eimeria spp., although they have a beneficial effect on recovery after infection, which was expressed by the favourable impact on compensatory growth and, thus, on the final performance indices.
Two experiments were conducted to determine optimal standardized ileal digestible (SID) tryptophan:lysine ratio for piglets using growth performance and plasma urea N as response criteria. In Experiment 1, piglets were fed 6 diets with 8.5, 9.5, 10.5, 11.5, 12.5 or 13.5 g · kg–1 SID lysine to estimate lysine requirement. In Experiment 2, piglets were fed 6 diets with 9.2 g · kg–1 SID lysine, and 0.178, 0.182, 0.196, 0.216, 0.227 or 0.236 SID trytophan:lysine to estimate optimal tryptophan:lysine ratio. The SID lysine requirement was estimated to be 10.2 g · kg–1. Response criteria measured were unaffected by SID tryptophan:lysine ratio, implying that the diets fed were not deficient in tryptophan. In conclusion, the SID lysine requirement for the piglets was close to the recommendation by NRC (1998; 10.1 g · kg–1), but not NRC (2012; 12.3 g · kg–1). The optimal SID tryptophan:lysine ratio of the piglets was either equal to or less than 0.178.
The aim of the study was to determine the usefulness of near-infrared spectroscopy (NIRS) for direct estimation of energy, protein and fillunits as well as organic matter digestibility (OMD) for wet whole-crop sorghum silages according to the French feeding system for ruminants INRA (1988). Fifty-eight whole-crop sorghum silages ensiled alone or with the addition of wheat bran, rapeseed meal, or whole-crop maize were used to create a calibration data set. Wet samples of silage were scanned using a spectrophotometer (570–1850 nm). The spectral data were transformed to the first derivative. For scatter correction, standard normal variate and detrending methods were used. The calibration equations were developed using modified partial least squares regression.The accuracy of each equation was evaluated based on the coefficient of determination of calibration (R2 ), standard error of calibration, and standard error of cross validation (SECV). High R2 (> 0.93) were shown for all parameters except OMD (R2 = 0.83).The highest SECV (0.62) was observed for protein units, but all errors were within acceptable values. The results of the study suggest that NIRS may be used for direct prediction of nutritive value of sorghum silages in INRA system units. Furthermore, these results suggest that the NIRS technique may be successfully used for direct estimation of feed units for ruminants in wet silages.
The objective of this study was to develop a model to assess economical and balanced feed rations for sport horses. It was based on nonparametric modelling with a combination of linear programming and a multiobjective optimization technique: weighted goal programming. The method incorporates multiple goals into optimization. The technical data presented the feed nutritional value (dry matter, metabolizable energy, metabolizable protein, etc.) and nutritional requirements, which were represented in weighted goal programming as targets. The model was tested for optimization of winter and summer feed rations, where summer feed rations are more expensive but more balanced. Optimization results show that the method of weighted goal programming is more accurate and useful in practice compared with linear programming, where only one goal (economically optimal feed rationing) is taken into account.
The purpose of the work was to determine the effect of the fi bre content in the mixture on morphometric traits of intestinal epithelium of fatteners. In one-phase fattening, 14 crossbred pigs were classifi ed into two groups and ad libitum fed the mixtures, differing in the composition and nutritional value, including the level of crude fi bre (control group – C – 3.4%; experimental group – E – 12%) but with the maintained energy-protein ratio (1 : 13). At the age of 180 days, the fattening was completed; the weight of the pigs from C group was equal to ca. 100 kg and that one of the pigs from group E was by ca. 26 kg lower. The rate of growth of pigs from group E as compared to the animals from group C was slower (P ≤ 0.01). After slaughter, morphometric evaluation of the scrapes from the following three segments of the small intestine was carried out: duodenum, jejunum and ileum. There was found a lower mitosis index (the number of divisions per one crypt) of the intestinal epithelium cells of the pigs from group E as compared to group C (duodenum, P ≤ 0.01). The height of the epithelial cells in crypts and depth of crypts in three examined segments of small intestine (D, J, I) was higher in group E vs. group C (P ≤ 0.05; P ≤ 0.01), whereas the villus height was lower in group E vs. group C. The fi bre level in the mixture affected the direction and level of changes in the examined indicators, characterizing the morphometric traits of intestinal epithelium.
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