Rumen fermentation and metabolic profile in conventional and gnotobiotic lambs.

Observations were carried out of actual acidity, volatile fatty acid (VFA) concentrations, enzyme activity in the rumen, total protein, urea, total lipid and glucose in the serum of conventional (CL) and gnotobiotic lambs (GL) in the period of milk nutrition. The inoculum of gnotobiotic lambs contained Streptococcus bovis, Prevoxella ruminicola, Butyrivibrio fibrisolvens and Selenomonas ruminantium at a concentration of 1.10(6) each. Throughout the observation period the pH of the rumen contents of gnotobiotic lambs ranged within 6.5-6.8 with a significant difference at an age of 7 weeks. Total VFA concentrations in the rumen contents were increased in the CL throughout milk nutrition: the differences at 4 and 5 weeks of age were significant. Total VFA in the conventional lambs revealed an increasing tendency between weeks 4 and 7, reaching higher levels at 7 weeks of age (57.1 mmol.l-1), whereas in the gnotobiotic animals the range (24.3-30.1 mmol.l-1) was narrow and the peak occurred at 6 weeks of age. In GL significantly increased molar proportions of acetic acid were observed whereas in CL the molar proportions of propionic acid proved to be significant increased. The molar proportions of butyric and valeric acids were increased in CL but the group differences were not significant. In GL no isoacids were found. Alpha amylase (E.C.3.2.1.1.) activity of the rumen contents was significantly increased in GL between weeks 2 and 6 of age whereas cellulase (endoglucanase E.C.3.2.1.4. and cellobiohydrolase E.C.3.2.1.91.) activity was significantly increased in 4-week-old CL. Over the whole period of milk nutrition no significant differences were observed in urease (E.C.3.5.1.5.) activity of the rumen contents in the examined groups. At 5 weeks of age significantly increased total protein levels were observed in the conventional animals with maximum levels occurring at 4 weeks of age (CL-59.5 g.l-1 GL-55.3 g.l-1). Urea levels in 6-week old conventional lambs were significantly higher than in the gnotobiotic animals (CL-6.4 mmol.l-1 vs. GL-1.9 mmol.l-1). As to glycaemia no significant group differences were recorded. In the conventional animals total lipid levels were significantly increased at 1 and 6 weeks of age with a peak occurring in the first week of life (7.5 g.l-1) whereas in the gnotobiotic lambs a significant increase was observed at 3 weeks of age, the peak being recorded in 4 week-old animals (4.3 g.l-1). Throughout the period of interest the mean daily weight gains in the conventional and gnotobiotic lambs presented 0.164 and 0.162 kg, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)

[Colonization of the digestive tract by defined lactoflora in gnotobiotic and conventional lambs]. / Kolonizácia tráviaceho traktu gnotobiotických a konvencných jahniat definovanou laktoflórou.

The effect of Lactobacillus casei 249/89 on the colonization of the intestinal tract and selected indicators of the metabolic profile of gnotobiotic and conventional lambs from the viewpoint of its possible utilization in the prevention of diarrhoeal syndrome of bacterial etiology in young animals has been studied. Five gnotobiotic and three conventional lambs were used in these studies. The lambs were slaughtered at 3, 6, 10, 15 and 21 days of age. The population of L. casei colonizing the intestinal epithelium was at the age dynamics on average higher in gnotobiotic lambs compared with lactobacilli in conventional lambs (Fig. 1). The significant difference (p < 0.001) was noted at the age of 3 days (gnotobiotic lambs = 3.40 log 10/cm2 and conventional lambs = 1.08 log 10/cm2). Also the counts of lactobacilli colonizing individual sections of the intestine (Fig. 2) was on average higher in gnotobiots with significant differences in jejunum and colon (p < 0.05). In both groups, the highest number of lactobacilli was observed on the intestinal epithelium in lower sections of the digestive tract. In gnotobiots, the population of L. casei colonizing the duodenum was highest at the age of 3 days (3.49 log 10/cm2), in jejunum (3.74 log 10/cm2) and in ileum 4.37 log 10/cm2) at the age of 6 days and in the colon (4.7 log 10/cm2) at the age of 15 days (Fig. 3). In conventional lambs, the population of lactobacilli colonizing individual sections of the intestinum was increasing with age (Fig. 4). The number of L. casei in the intestinal content of gnotobiotic lambs was on average higher than that in conventional animals but the differences were not significant. In both groups, the highest number of lactobacilli was noted at the age of 10 days (gnotobiotic lambs = 5.9 log 10/ml; the conventional lambs = 4.6 log 10/ml). From the viewpoint of individual sections of the intestine, the population of L. casei in the intestinal content of gnotobiotic lambs was higher than the lactobacilli count in conventional animals with significant difference in jejunum (p < 0.01). In gnotobiots, the highest lactobacilli count was in the colon (6.17 log 10/ml); in conventional lambs in the ileum (4.71 log 10/ml).(ABSTRACT TRUNCATED AT 400 WORDS)

[The recovery and rearing of gnotobiotic lambs and their use in veterinary medicine]. / Získavanie a odchov gnotobiotických jahniat a ich vyuzitie vo veterinárnej medicíne.

Our own innovated method of the hysterectomy recovery of gnotobiotic lambs, modified equipment for gnotobiote rearing, management and tending techniques were tested in this study. A hysterectomy hood (Fig. 1) was made from plexiglass and it fully met the requirements for simple and rapid handling. Our own modified isolator for gnotobiotic lamb rearing (Fig. 2) made out of glass-reinforced plastic with plexiglass sight holes was used for group rearing. It was more resistant to mechanical damage in comparison with the isolators equipped with PVC sheet pouches. The use of an isolator for feed and material (Fig. 3) and of an isolator for waste material storage with a PVC sheet pouch was found to be very practical; these isolators were connected to the rearing isolator through piping. The ventilation system was sufficient enough. An emasculator was used for hysterectomy. The method is simple and rapid, reliable and it enabled to preserve lambing ewes for other experimental purposes. Gnotobiotic lambs were successfully fed a milk replacer for calves. Samples of biological material (blood, rumen fluid, droppings) were taken from lambs kept in the isolator. The isolators were sterilized with 2% solution of peracetic acid sprayed as aerosol. Milk, materials made of glass and metal were autoclaved at a temperature of 121 degrees C, pressure 1.2 atm, for 30 minutes, and the concentrate mixture was sterilized with an X-ray dose of 2.5 Mrad. All the used methods of sterilization were fully efficient. A modified method reliably detecting lamb and isolator contamination was used for microbiological monitoring.(ABSTRACT TRUNCATED AT 250 WORDS)