The aim of the study was to identify the effect of fattening of experimental Simmental bulls (a total of 10 animals) with a high-concentrate diet on ruminal mucosa and dimensions of ruminal papillae, and to assess the intensity of keratinization of papillary epithelium. The experimental period lasted from weaning to slaughter (359 days). Histopathological and morphometric examinations of ruminal mucosa indicated that the ruminal papillae of bulls from the experimental group were better developed (long with a lower degree of keratinization) compared to the control group. Significant differences between the experimental and control groups were found in the length of ruminal papillae (p = 0.005), width of stratum corneum (p = 0.034) and degree of mucosal keratinization on the surface of ruminal papillae (p = 0.014). Conclusive results of morphometric analysis prove the facility of the use of morphometrics as a method useful for veterinary pathology, mainly for the accuracy of the histological diagnosis. Cattle, rumen, grain, morphometry, ruminal epitheliumThe rumen in young suckling ruminants is small, about half the size of the abomasum. It undergoes significant morphological and physiological changes during the growth of the animal. In cattle, the ratio between the rumen and abomasum of 4 week-old-calves is 1:2, at 8 weeks of age 1:1, at 3 months 2:1 and in the adult cattle 9:1 (Rosenberger 1964).The ruminal mucosa consists of a multilayer squamous epithelium with significant keratinisation. The lining has papillae of tongue-like shape on the surface with the length of 1-13 mm and width of 0.5-3 mm, and these significantly increase the surface of the ruminal epithelium (Hofmann and Schnorr 1982;Langer 1988;Frappier 2006). The longest papillae are located in the blunt sacs, at the bottom of the ventral sac and the bottom of the ruminal antrum. The length decreases towards the columns and on the edge there are only low papillae or they disappear completely (Jelínek 1995;König et al. 2004).The morphological properties of the gut lining including the size of papillae and their quantity are variable. The pathogenesis of morphological adaptation of the ruminal mucosa depends on several factors, such as age of the animal, composition and quality of feed, fibre content, and type, concentration and ratio of volatile fatty acids (VFA), ruminal content pH, intensity of fermentation processes in the rumen, etc. (Zitnan et al. 2003;Radostits et al. 2007). The ruminal papillae are rudimentary in newborn and young animals, therefore the mucosa is relatively smooth and pale (Jelínek 1995;Amaral et al. 2005). Under physiological conditions, mature papillae are covered with a thin layer of keratinising squamous cells (Frappier 2006). Morphology of the ruminal mucosa relates to concentrations of volatile fatty acids (VFA), mainly those of butyric and propionic acids. It is characterised by a process of continual changes, from regression to proliferation. The

The aim of this study was to confirm the presumption that the duodenal flow of soluble nitrogen fractions: soluble non-ammonia nitrogen (SNAN), soluble protein and long-chain peptides nitrogen (SPLPN), soluble short-chain peptides and free amino acids nitrogen (SSPFAAN) and free amino acids (FAA) will be increased after the application of ruminally protected tablets containing soya protein and amino acids (Met, Lys, His). Control animals received the same mixture but in ruminally non-protected (powder) form. The experiment was carried out on three lactating Holstein cows of average weight of 523 kg fitted with ruminal and duodenal cannulas. The experiment was divided into 4 periods of 14 d (10 d preliminary period and a 4-d experimental period). In the first period one cow received the tablets (T) and the other two received the powder (C) with the same composition. In the subsequent period the rate of animals was antipodal. Cows were fed on diet based on maize silage, lucerne hay and a supplemental mixture. Powder or tablets consisted of purified soya-protein HP 300, Lys, Met and His. The experimental treatment did not significantly (P>0.05) influence duodenal flow of SNAN, SPLPN and SSPFAAN. In case of FAA significant (P<0.05) increase of flow (in g/day) was obtained in T group for Met (1.25 vs 0.35), Lys (2.07 vs 0.76), His (2.13 vs 0.49) and Arg (0.37 vs 0.15) against the control C.

Radiography of the distal interphalangeal joints of two limbs of a cadaver of a horse weighing 550 kg was conducted in the present study. The examination was performed on lateromedial, palmaroproximal-palmarodistal views and on dorsoproximal-palmarodistal, dorsolateralpalmaromedial, dorsomedial-palmarolateral views of a raised limb placed on a navicular block, and of weight-bearing limbs. During the examination, doses of scattered radiation were measured at the sites of radiographer, assistant holding a film cassette and assistant positioning the examined limb or the opposite one. The lowest radiation dose was received by the assistant holding the cassette behind the examined region; a total equivalent dose of 183.6 -201.7 nSv was received by his hands and genitals, and 110.8 -113.3 nSv by his eye lens and neck during the examination of the distal interphalangeal joint. The radiographer was exposed to higher radiation; an equivalent dose of 846.6 -854.1 nSv was received by his hands and genitals, and 271.8 -328.2 nSv by the eye lens and the neck. The highest scattered radiation dose was received by the assistant positioning the examined limbs; equivalent doses were 7751 -9354 nSv (hands), 1117.3 -1119.5 nSv (genitals), and 880.6 -1096.2 nSv (eye lens and neck). The equivalent dose values measured, received by the radiographer and the assistants during the examination of the distal interphalangeal joint seem to be very low relative to radiation exposure limits. However, it must be taken into account that the personnel involved in radiography is also exposed to scattered radiation during other examinations where radiation doses are often much higher. These results indicate the necessity to use protective lead aprons, gloves and collars during radiography of the distal interphalangeal joint.

·tercová E., D. Haas, A. Krása, R. Lepková, J. ·terc: Effect of Intensive Fattening of Bulls Fed a High-grain Diet on Selected Health Indicators. Acta Vet. Brno, 2006, 75: 209-218.The aim of the study was to investigate the effect of intensive fattening of bulls with a high-grain diet on selected health parameters. Metabolic indicators under study were compared with those in bulls receiving a traditional diet based on maize silage. The trial included 18 Czech pied bulls that were fed a diet containing from 75.0% to 83.6% concentrate on dry matter basis. As a control, 18 Czech pied bulls were used, given total mixed ration based on maize silage. The experiment was started after weaning when the treated group averaged 114 days of age and the control group 115 days of age. Bulls were slaughtered at an average age of 473 days in the treated group and 474 days in the control group. The experiment lasted 359 days. In the fattening period, blood and rumen fluid samples were withdrawn to evaluate rumen fermentation, acid-base balance and selected biochemical indicators. After the slaughter, samples of tuber coxae cancellous tissue were collected for the bone metabolism assessment. Among indicators under study, the rumen fermentation ones were the most affected by feeding the high-grain diet. Bulls fed the high-grain diet showed (P ≤ 0.05) lower rumen fluid pH and a higher total titration activity, a higher (P ≤ 0.01) total level of VFA and propionate proportion, and a lower (P ≤ 0.01) acetate proportion than the control bulls. Counts of infusoria were also lower (P ≤ 0.01). Acid-base balance was not significantly influenced by feeding the high-grain diet. The high-grain diet fed bulls showed increased serum levels of AST and phosphorus, but the differences from the control group were non-significant in most cases. In 1 g bone ash of the samples of tuber coxae cancellous tissue in the treated group calcium content was significantly (P ≤ 0.05) lower than in the control group; no significant differences were observed between other indicators under investigation. Feeding, concentrate, rumen fermentation, acid-base balance, bone metabolismGenerally, high-grain diets cause a decrease in ruminal pH, which may lead to the development of rumen acidosis. The risk has been pointed out by many researchers such as Nocek (1997), Owens et al. (1998) and Galyean and Rivera (2002). Excessive carbohydrate intake causes the growth of G+ bacteria, mainly lactate producing streptococci and lactobacilli (Nocek 1997;Owens et al. 1998). A drop in ruminal pH below 6.0, due to diets with a high proportion of grain (70-95%, on DM basis), was reported by Harmon et al. (1985), Leedle et al. (1995), Goad et al. (1998), Hristov et al. (2001 and Schoonmaker et al. (2003). Some of them observed a concurrent increase in lactate and total VFA concentrations in rumen fluid (Harmon et al. 1985;Leedle et al. 1995;Goad et al. 1998). However, Hristov et al. (2001 observed low lactate levels in steers fed 95% concentrate diet (on DM basis), probably d...

The aim of the study was to evaluate the growth rate and selected carcass and meat quality parameters in bulls fed a high-grain diet and to compare the results with those obtained in bulls fed a diet based on preserved roughage. The trial included 18 Czech-Pied bulls fed a diet with a high proportion of concentrated feed and 18 Czech-Pied bulls fed a diet based on maize silage, used as a control group. The trial was launched after the weaning of calves. During the fattening period, live weight and average daily weight gain were monitored. The bulls were slaughtered at the live weight of 550–600 kg, the mean age at slaughter was 473 days for the high-grain diet group and 474 days for the control group. The carcasses were classified to SEUROP quality grades, and carcass gain and dressing percentage were calculated. Samples of <I>m. longissimus pars thoracis</I> were taken from five bulls in each group to examine selected meat quality parameters. In the period from weaning to slaughter the high-grain diet bulls and the control bulls achieved the average daily weight gain of 1.29 kg and 1.21 kg, respectively. Differences between the groups were not significant. The high-grain diet group showed higher average carcass weight and higher carcass weight gain, differences between the groups were not significant, either. As to meat quality parameters under study, a significant difference was found only in meat lightness (L*), with the mean value in the high-grain diet group being significantly (<I>P</I> ≤ 0.01) lower than in the control group. The other meat quality parameters did not show any significant differences between the groups. In this study, the high-grain diet gave similar performance as the maize silage-based diet in fattening bulls. The high-grain diet group and control group showed comparable average daily weight gain and selected carcass and meat quality parameters.