Nutrient digestibility and prediction of metabolizable energy in total mixed rations for ruminants.

The aim of the present study was to determine equations that predict ME in total mixed rations (TMR) based on routine methods. The ME content of 30 TMR for dairy cows was determined based on digestible crude nutrients obtained with wether sheep. Concentrations in the TMR (in g/kg DM) varied between 118 and 234 for crude protein, 26 and 48 for crude lipid, 131 and 250 for crude fibre, 281 and 488 for NDF, and 173 and 304 for ADF. Gas production ranged from 40.7 to 54.1 ml/200 mg DM, and enzymatically degraded organic matter from 652 to 800 g/kg DM. Digestibility [%] ranged from 68.6 to 84.0 for organic matter, from 55.6 to 84.3 for crude lipid, from 55.0 to 77.8 for crude fibre, from 57.6 to 77.0 for NDF and from 53.1 to 79.6 for ADF. ME ranged from 9.6 to 11.9 MJ/kg DM, and NEL from 5.7 to 7.4 MJ/kg DM. ME content was highly correlated with the concentration of both crude fibre and enzymatically degradable organic matter as well as with organic matter digestibility. A multiple regression equation based on crude fibre and crude lipid predicted ME with a reasonable goodness of fit (r2 = 0.81; s(y.x) = 2.4%). The inclusion of other nutrients, of neutral and acid detergent fibre, neither of gas production did improve the goodness of fit. The best prediction was achieved with inclusion of enzymatically degraded organic matter (r2 = 0.90; s(y.x) = 1.7%).     

Bidirectional selection for dustbathing activity in Japanese quail (Coturnix coturnix japonica)

1. Divergent selection was conducted in male Japanese quail for high and low dustbathing activity as measured by the number of dust tosses during a dustbathing bout.

2. After 9 generations of selection the low, control and high lines averaged 6–9, 12.9 and 23.8 dust tosses per dustbathing bout respectively. Realised heritabilities in the low and high lines were 0.21±0.06 and 0.25±0.06 respectively, and agreed well with the heritability coefficient of 0.27±0.04 based on the combined sire and dam estimate from the sib analysis.

3. Correlated responses, similar to those in the selected trait, were found in the duration of the dustbathing bout and in the intensity index (the number of dust tosses per minute during a dustbathing bout). Heritabilities of latency, duration and intensity index were estimated as 0.14±0.04, 0.30±0.04 and 0.26±0.04 respectively.

4. It is concluded that postulated ethological needs may vary considerably between strains according to their genetic background and the previous history of selection of the birds during domestication.     

Morphology of the lymph nodes in bottlenose dolphin (Tursiops truncatus) and striped dolphin (Stenella coeruleoalba) from the Adriatic Sea

Morphology of the lymph nodes was examined in six bottlenose dolphins (Tursiops truncatus) and three striped dolphins (Stenella coeruleoalba) from the Adriatic Sea. All animals had been found dead in nature. One group of the nodes was taken from the tracheal branching area and was marked as bifurcational lymph node, and the other group was taken from the mesenteric root and was marked as mesenteric lymph node. Microscopic analysis showed that the lymph nodes in both dolphin species were surrounded by a connective tissue capsule comprising smooth muscle cells. The parenchyma of the mesenteric and bifurcational lymph nodes in bottlenose dolphin was divided into the peripherally situated cortex with the lymphatic nodules and diffuse lymphatic tissue, and the centrally situated medulla structured of the medullary cords separated by the medullary sinuses. These lymph nodes structurally correspond to the lymph nodes in the majority of terrestrial mammals. The mesenteric lymph node of striped dolphin also had a peripherally situated cortex and a centrally positioned medulla as the majority of terrestrial mammals. In the bifurcational lymph nodes of striped dolphin, there was a central dense lymphatic tissue with the lymphatic nodules and a peripheral less dense lymphatic tissue structured of the cell cords and sinuses. The bifurcational lymph node in striped dolphin resembled porcine lymph nodes and belonged to the inverse lymph nodes.     

Comparison of methods for antimicrobial susceptibility testing and MIC values for pleuromutilin drugs for Brachyspira hyodysenteriae isolated in Germany

In Germany treatment of swine dysentery is hampered by Brachyspira hyodysenteriae strains showing elevated MIC values to the few antibiotics licensed. Therefore, susceptibility testing of clinical isolates is an important service to the swine practitioner. This study compares the established agar dilution procedure for antimicrobial susceptibility testing of this fastidious anaerobe to the broth microdilution test newly developed [Anim. Health Res. 2 (2001) 59; Vet. Microbiol. 84 (2002) 123; J. Clin. Microbiol. 41 (2003) 2596]. A total of 221 isolates were examined twice with either test procedure using tiamulin and valnemulin as antibiotics. Both methods gave reproducible results, and the MIC values for the reference strains B. hyodysenteriae B204 and Staphylococcus aureus ATCC 29213 corresponded to previously published data. However, the results for individual strains differed significantly for both tests (P < 0.001) with MIC values being on average one dilution step lower in the broth dilution method. The 221 strains used for comparing test procedures were isolated between 1989 and 2001. An additional 102 strains isolated in 2002 were tested only with the broth dilution procedure. A significant rise in the average MIC value for both pleuromutilins could be demonstrated when comparing earlier isolates to those from 2000 to 2001 (P < 0.05), while in 2002 the average MIC significantly decreased when compared to the value in 2000 (P < 0.05). However, strains with MIC values for tiamulin as high as 8 microg/ml (broth dilution) could still be isolated.     

Passive immunization in neonatal piglets in natural rearing--effects of birth order, birth weight, litter size and parity

603 neonatal piglets (German Landrace) were investigated for passive immunization affected by birth order, birth weight, litter size and parity. Concentrations of immunoglobulins in the blood serum of piglets on the first day of life served as measure for passive immunization. Blood samples were drawn at 12, 18 and 24 hours post partum. Quantitative measurements of immunoglobulin classes were carried out by radial immunodiffusion. There was a significant effect of birth order, because of the rapid changes in colostrum composition between onset of birth and the last piglet of each litter. The effect of birth weight was only partly significant and different for the immunoglobulin classes. There was no significant effect of litter size on passive immunization. Parity had a significant positive effect on IgG- and IgA-concentrations in sow's colostrum with litter two to six, parity 1 and 2 lead to highest IgM concentrations in the blood serum of piglets.     

Pigeons as a possible reservoir of Shiga toxin 2f-producing Escherichia coli pathogenic to humans

Escherichia coli harboring stx2f which secrete the respective Shiga toxin (Stx) are frequently found in pigeons. In this report we describe the isolation of a stx2f-containing E. coli O128 strain from an 11-month old child with diarrhea and comparison of this strain with stx2f-positive E. coli isolates from droppings of pigeons. The human E. coli O128:NM (nonmotile) isolate had a fliC restriction fragment length polymorphism pattern identical to that in one of the pigeon isolates belonging to the serotype O128:H2. All isolates examined, including that from the patient and five from pigeons, contained the intimin-encoding eae gene in addition to stx2f and all of the strains possessed the gene encoding the major subunit of the long polar fimbriae in enterohemorrhagic E. coli (EHEC) 026. Plasmid-associated virulence genes such as EHEC-hlyA, as well as urease and tellurite resistance-encoding operons were absent from all the strains and this correlated with their lack of hemolytic activity and urease production and tellurite sensitivity. These features, together with the sorbitol fermentation phenotype of Stx2f-producing E. coli, hamper the laboratory diagnosis of these strains. Our data demonstrate that pigeons may be a reservoir of Stx2f-producing E. coli strains associated with human disease.     

Home-monitoring of blood glucose in cats with diabetes mellitus: evaluation over a 4-month period

Home-monitoring of blood glucose concentrations has recently been introduced to owners. The objectives of this study were to investigate the feasibility of home-monitoring of blood glucose in diabetic cats by owners, the problems encountered and to compare glucose concentrations at home with those measured in the hospital. Twelve of 15 cat owners were able to generate glucose curves over the study period of 4 months. Most problems were related to restraining the cat, generating negative pressure with the lancing device and producing a blood drop. In the majority of cases, these problems could be resolved during the study. Blood glucose concentrations in the clinic tended to be lower than at home; some of the differences were significant. No association between tolerance of the procedure and blood glucose concentrations measured at home was found. We, therefore, assume that the lower glucose levels in the hospital were caused by lack of food intake. In 38% of cases, treatment based on hospital curves would have been different from that based on home curves. Home-monitoring appears to be a valuable tool in the management of cats with diabetes mellitus. One of its major advantages is that it enables frequent generation of blood glucose curves, which is of particular importance in cats that are difficult to regulate.     

Germination and appressiorial formation by uredospores ofUromyces viciae-fabae exposed to inhibitors of polyamine biosynthesis

An examination was made of the effects of three polyamine biosynthesis inhibitors on germination and appressorium formation by uredospores of the bean rust fungusUromyces viciae-fabea on artificial membranes. The ornithine decarboxylase inhibitor -difluoromethylornithine had no effect on uredospore germination, even when used at 2mM, whereas appressorium formation was reduced by 63% at 0.5 mM and by 99% at 2mM. Methylglyoxal bis(guanylhydrazone), an inhibitor of S-andenosylmethionine decarboxylase, reduced germination when used at 0.025 mM, and at this concentration, appressorium formation was completed prevented. Uredospore germination was unaffected by as much as 3 mM cyclohexylamine, an inhibitor of spermidine esynthase, while appressorium formation was reduced at 1 mM and completely prevented at 3.3 mM. These results support previous suggestions that inhibitors of polyamine biosynthesis exert their main effect on the early stages of fungal development on the leaf surface.Abbreviantions CHA cyclohyxylamine - DFMO -difluoromethylornithine - MGBG methylglyoxal bis(guanylhydrazone)     

Comparison of barometric whole body plethysmography and its derived parameter enhanced pause (PENH) with conventional respiratory mechanics in healthy Beagle dogs

The purpose of the study was to compare barometric whole body plethysmography (BWBP) and its derived parameter, enhanced pause (PENH), with conventional respiratory mechanics measurements. Resistance (RL), dynamic compliance (Cdyn) and pleural pressure changes were measured in six healthy anaesthetised Beagle dogs using a pneumotachograph and oesophageal balloon technique consecutive to BWBP-derived variables. Upper airway airflow limitation was established (1) by a filter or (2) by insertion of a narrow endotracheal tube. Bronchoconstriction was induced by nebulisation of carbachol at increasing concentrations until PENH exceeded 300% baseline. Upper airway narrowing significantly increased resistance (baseline RL 2.0+/-0.3, RL filter 11.8+/-3.2, RL luminal narrowing 21.1+/-2.3cm H(2)O/L/s; P <0.03), whereas PENH did not change significantly (baseline PENH 0.55+/-0.17, PENH filter 0.49+/-0.10; PENH luminal narrowing 0.50+/-0.18; P >0.05). Carbachol-induced bronchoconstriction caused a significant increase in PENH (baseline PENH 0.43+/-0.14, PENH carbachol 2.62+/-2.14; P <0.02) and resistance (baseline RL 2.1+/-0.3, RL carbachol 28.8+/-13.0 cm H2O/L/s; P <0.01), and a pronounced drop in compliance (baseline Cdyn 163.3+/-73.9, Cdyn carbachol 9.7+/-2.9mL/cmH2O; P <0.02). It was concluded that BWBP detects airflow limitation due to bronchoconstriction but not due to upper airway obstruction in healthy dogs. BWBP represents a valid, although not very sensitive screening tool for respiratory function testing.