Search

The distribution of Chabertia (Ch.) ovina, Oesophagostomum (O.) venulosum and Trichuris spp. within the large intestine of naturally infected sheep in the dependence of worm counts and the presence of nematodes of other species or genera was evaluated. The large intestine was divided into 4 sections. More than 75% of Ch. ovina were found within the disk-like section of the colon independently from worm count and presence of nematodes of other species. O. venulosum and Trichuris spp. preferred the caecum and the first section of the colon up to the beginning of the disk-like section. In both, the share of worms recovered from the first section of the colon did increase with higher worm counts. The simultaneous presence of O. venulosum and Trichuris spp. had a significantly negative influence on the share of Trichuris spp. isolated from the caecum.

The relationship between the faecal egg count and the worm burden of the gastrointestinal tract of sheep was examined. Close relationships were found in strongyles, Trichostrongylidae (other than Nematodirus spp.), Nematodirus spp., Strongyloides papillosus, Chabertiidae and Trichuris spp.. Due to high percentage of false negative diagnosis from faecal examination, this relationship was in Nematodirus spp. and Trichuris spp. not as close as in the other nematodes. However, the results support the high diagnostic value of quantitative faecal examinations in sheep.

The helminth fauna of 136 slaughtered sheep (99 lambs1 year, and 37 sheepor = 1 year) from Upper Bavaria, Germany, was examined. In all 2 species of trematodes, 3 species of cestodes and 24 species of nematodes were found. All the animals harboured gastrointestinal nematodes, 9 of them liver flukes, 33 Moniezia spp., 19 Cysticercus tenuicollis, and one sheep Setaria sp. Lungworms were not seen. The most prevalent species were Cooperia curticei (74.3%), Trichuris ovis (69.1%), Ostertagia circumcincta (68.4%), Oesophagostomum venulosum (63.2%) and Chabertia ovina (61.8%). The highest mean wormburden was seen in Cooperia curticei (12471) followed by Trichostrongylus axei (1856), Trichostrongylus colubriformis (1752), Nematodirus filicollis (1551) and Nematodirus battus (1238). In both lambs and older sheep the small intestine harboured the highest wormburden followed by abomasum and large intestine. The total nematode counts were much higher in lambs than in older sheep. The lambs harboured more intestinal nematodes than older sheep but fewer abomasal worms.

A theoretical study of a thermal microflowmeter, having two heating zones, in thermal and aerodynamic steady state. Due notice has been taken of heat emission in the pipe and in the fluid as well as exterior loss, and also the axial conduction in the pipe and in the fluid. An analytical expression of fluid and pipe temperature along the axis is obtained. Numerical analysis of the model is made from a program including the main possible outlines for a microflowmeter construction. The validity of the model has been studied and experimentally tested.

Resume A partir de la determination experimentale de la chaleur de reaction dans une solution de soude normale, nous avons calcule l'enthalpie de formation standard: - de l'oxydifluorure de selenium SeOF 2 SeOF 2 (l) + 4 NaOH(aq) → Na 2 SeO 3 (aq) + 2 NaF(aq) + 2 H 2 O(l) Δ°H f298 (SeOF 2 ,l = - 137,2 ± 3,8 kcal. mol. −1 ou - 574,0 ± 15,9 kj.mol. −1 - du tetrafluorure de selenium SeF 4 SeF 4 (l) + 6 NaOH(aq) → Na 2 SeO 3 (aq) + 4 NaF(aq) + 3 H 2 O(l) Δ°H f298 (SeF 4 ,l)= - 203,0 ± 5,8 kcal.mol. −1 ou - 849,4 ± 24,3 kj.mol. −1 Une methode d'estimation conduit pour cette energie de formation de SeF 4 (l) a la valeur - 189 kcal.mol. −1 ou - 791 kj.mol. -1

Resume Le tetrafluorure de tellure a ete prepare, puis des analyses diverses (chimique, termique, radiocristallographique) ont ete conduites. Nous avons ensuite determine l'enthalpie de fusion (δH fus = 3,02 Kcal.mol -1 *) et les capacites calorifiques de TeF 4 solide entre 298 et 402°K (Cp s = 30 cal.K -1 .mol -1 et de TeF 4 liquide a 423°K (Cp 1 = 31, 1 cal.K -1 .mol -1 pour aboutir aux courbes enthalpiques.

Resume Le tetrafluorure et l'oxydifluorure de selenium ont ete prepares, purifies et analyses par diverses methodes (analyses chimique, thermique, par microsublimation, par spectrometrie de masse). Nous avons determine la temperature et l'enthalpie de fusion de ces deux composes ainsi que l'enthalpie de vaporisation de l'oxydifluorure de selenium.

Resume Nous avons determine l'enthalpie de formation standard du tetrafluorure de tellure: a partir de la chaleur de combustion de ce compose dans le fluor a partir de la chaluer de reaction de ce compose dans une solution de soude normale