Concentrations of metals (zinc, copper, cadmium, and mercury) in three domestic ducks in France: Pekin, Muscovy, and Mule ducks

The role of different factors such as biological material (tissues, organs) and trophic condition (overfeeding or not) in the metal accumulation was studied in three genotypes of ducks (Pekin, Muscovy, and Mule) under breeding conditions. Results showed that overfeeding decreased the concentration in Cd, Cu, and Zn through the dilution process. In contrast, mercury concentration increased with this method. A relation between lipidic metabolism of genotypes and the distribution of this metal in biological material was found. Domestic ducks were little contaminated, but a low chronic contamination in Cd was observed, probably coming from the food. Due to the low levels of contamination observed in these breeding ducks, they can be considered as a good control for further contamination studies and comparison with accumulation levels recorded in the field. The impact of feeding condition on accumulation showed the importance of taking into account the life cycle of birds before studying their contamination and the impact of pollutants.     

Difference in factors explaining growth rate variability in European eel subpopulations: the possible role of habitat carrying capacity

As a key parameter in the management of fish populations, individual growth rate (GR) variations were examined in the European eel (Anguilla anguilla; > 150 mm) using extensive mark–recapture surveys in the lotic habitats of two small rivers of western France: the Frémur, supposed to be saturated, and at the same latitude, the Oir with densities fivefold lower than those of the Frémur. In both systems, generalised linear models were used to test whether spatiotemporal factors such as dominant habitat type or local density affect GR variability. In the presumed unsaturated system, the Oir, GR variability is mainly explained by a set of habitat suitability drivers (density, dominant habitat type). In the Frémur, GRs appear independent of differences in habitat density or productivity. Below saturation, an increase in density will decrease the GR through intraspecific competition. At saturation, intraspecific competition reaches such high levels that regardless of eel density and productivity, the resources available by individual are similar throughout the system. In these circumstances, the effect of density on growth was presumed undetectable. Despite these contrasted results, mean GRs observed in both catchments were closed (~20 mm·year^?1). This is an unexpected result as GR is expected to be higher in unsaturated systems. This similarity could be explained by the difference between the two systems in terms of: (i) sex ratio (the Frémur is dominated by male, whereas the female is dominant in the Oir), (ii) habitat type distribution or (iii) possible interspecific competition (important salmonid populations in the Oir).     

Prokinetic effects of erythromycin on the ileum, cecum, and pelvic flexure of horses during the postoperative period

OBJECTIVE: To evaluate the effect of erythromycin on motility of the ileum, cecum, and pelvic flexure of horses during the postoperative and post-recovery periods. ANIMALS: 8 healthy adult horses. PROCEDURE: Horses were anesthetized and bipolar electrodes were implanted in smooth muscle of the ileum, cecum, and pelvic flexure. Approximately 4, 16, and 24 hours (postoperative recording sessions) and at least 8 days (post-recovery recording session) after surgery, myoelectric activity was recorded before and after administration of erythromycin (0.5 mg/kg). RESULTS: Following erythromycin administration, myoelectric activity was increased in the ileum during all postoperative recording sessions but not during the post-recovery recording session. Myoelectric activity was increased in the cecum following erythromycin administration only during the post-recovery recording session. Myoelectric activity was increased in the pelvic flexure following erythromycin administration during all recording sessions. During several recording sessions, there were short periods during which myoelectric activity was significantly decreased following erythromycin administration. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that erythromycin has an effect on myoelectric activity of the ileum, cecum, and pelvic flexure in horses; however, prokinetic effects of erythromycin administered during the postoperative period were not always the same as effects obtained when the drug was administered after horses had recovered from the effects of surgical implantation of recording devices. Therefore, caution must be exercised when extrapolating results of prokinetic studies in healthy animals to animals with abnormal gastrointestinal tract motility.     

Abomasal displacement and volvulus in beef cattle: 19 cases (1988-1998)

OBJECTIVE: To assess signalment, history, results of clinical and laboratory testing, and outcome for beef cattle with a left displaced abomasum (LDA), right displaced abomasum (RDA), or abomasal volvulus (AV). DESIGN: Retrospective study. ANIMALS: 19 beef cattle with an AV, LDA, or RDA. PROCEDURE: Signalment; history; results of physical examination, diagnostic testing, and surgical exploration; and condition of the animal at discharge were obtained from medical records. RESULTS: Fourteen cattle had an AV, 4 had an RDA, and 1 had an LDA. Duration of clinical signs ranged from 1 to 21 days. Eighteen cattle had an AV or RDA; 7 were Brahmans, 12 were males, and median age was 10 months. Abdominal distention was observed in 11 cattle, heart rate of > or = 100 beats/minute was detected in 14, and the abomasum was palpable per rectum in all cattle in which per rectal examination was performed. Leukocytosis, neutrophilia, hyperglycemia, azotemia, hypochloremia, and hypokalemia were common laboratory findings. At surgery, 3 cattle with an AV or RDA had a ruptured abomasum. Of the remaining 15 cattle, 12 survived. CONCLUSIONS: Clinical course in beef cattle with an AV or RDA was more protracted than that typically associated with these conditions in dairy cattle, but survival rate in beef cattle that did not have rupture of the abomasum was similar to that of dairy cattle. CLINICAL RELEVANCE: Abomasal displacement should be considered for beef cattle with abdominal distention. Prognostic indicators recommended for use in dairy cattle may not be useful for beef cattle.     

Fragrance heritability in Hybrid Tea roses

Most of the Hybrid Tea roses that are sold as cut flowers are non-scented, despite the long-standing interest of the perfume industry to rose scent. In the absence of comprehensive knowledge on the genetic and biochemistry of volatile biosynthesis in roses, we decided to characterize a Hybrid Tea progeny obtained from parents that emit very different scents. First, we identified the 11 most abundant volatile compounds synthesized by the progeny, and a short review is given for each one that describes their occurrence in the genus Rosa, in the parents and the studied progeny. We have then used statistical analysis on the distribution of volatiles among individual progeny members to unveil the laws of segregation of the scent traits in this cross. As a general rule, the quantity and quality of volatile compounds was lower in the progeny members. Variations in scent quality were mostly linked to the quantity of monoterpenes that was present. Offsprings emitting a pleasant fragrance were, in practice, found to be rare.     

Host status and reaction of <Emphasis Type="Italic">Medicago truncatula</Emphasis> accessions to infection by three major pathogens of pea (<Emphasis Type="Italic">Pisum sativum</Emphasis>) and alfalfa (<Emphasis Type="Italic">Medicago sativa</Emphasis>)

Ditylenchus dipsaci, the stem nematode of alfalfa (Medicago sativa), Mycosphaerella pinodes, cause of Ascochyta blight in pea (Pisum sativum) and Aphanomyces euteiches, cause of pea root rot, result in major yield losses in French alfalfa and pea crops. These diseases are difficult to control and the partial resistances currently available are not effective enough. Medicago truncatula, the barrel medic, is the legume model for genetic studies, which should lead to the identification and characterization of new resistance genes for pathogens. We evaluated a collection of 34 accessions of M. truncatula and nine accessions from three other species (two from M. italica, six from M. littoralis and one from M. polymorpha) for resistance to these three major diseases. We developed screening tests, including standard host references, for each pathogen. Most of the accessions tested were resistant to D. dipsaci, with only three accessions classified as susceptible. A very high level of resistance to M. pinodes was observed among the accessions, none of which was susceptible to this pathogen. Conversely, a high level of variation, from resistant to susceptible accessions, was identified in response to infection by A. euteiches.     

A Syndrome Resembling Idiopathic Noncirrhotic Portal Hypertension in 4 Young Doberman Pinschers

We describe 4 young male Doberman Pinschers (3 littermates and 1 unrelated dog) with a syndrome resembling idiopathic or noncirrhotic portal hypertension of humans. Each dog was evaluated for a hepatopathy resulting in portal hypertension, development of portosystemic collateral vessels, and hepatic encephalopathy. These dogs differ from previous reports of young dogs with hepatic insufficiency associated with portal hypertension and acquired portal systemic shunting by their lack of intrahepatic arteriovenous fistulae, portal vein atresia, or intrahepatic fibrosis. Clinicopathologic features included erythrocyte microcytosis, normal to mildly increased liver enzyme activities, increased concentrations of serum bile acids, reduced plasma indocyanine green clearance, and normal total bilirubin concentration. Abdominal ultrasonography disclosed a small liver and portosystemic collateral vessels. Radiographic imaging studies confirmed hepatofugal portal circulation and discounted hepatic arteriovenous fistulae. Histopathologic features in liver tissue from each dog were similar and consistent in all sections examined. Common findings included increased cross-sectional views of hepatic arterioles; hepatic lobular atrophy; scanty increase in connective tissue around some large portal triads; and absence of inflammation, disturbed lobular architecture, bile duct proliferation, or intrahepatic cholestasis.     

Green tea polyphenol extract regulates the expression of genes involved in glucose uptake and insulin signaling in rats fed a high fructose diet

Green tea has antidiabetic, antiobesity, and anti-inflammatory activities in animal models, but the molecular mechanisms of these effects have not been fully understood. Quantitative real-time polymerase chain reaction (PCR) was used to investigate the relative expression levels and the effects of green tea (1 and 2 g solid extract/kg diet) on the expression of glucose transporter family genes (Glut1/Slc2a1, Glut2/Slc2a2, Glut3/Slc2a3, and Glut4/Slc2a4) and insulin signaling pathway genes (Ins1, Ins2, Insr, Irs1, Irs2, Akt1, Grb2, Igf1, Igf2, Igf1r, Igf2r, Gsk3b, Gys1, Pik3cb, Pik3r1, Shc1, and Sos1) in liver and muscle of rats fed a high-fructose diet known to induce insulin resistance and oxidative stress. Glut2 and Glut4 were the major Glut mRNAs in rat liver and muscle, respectively. Green tea extract (1 g) increased Glut1, Glut4, Gsk3b, and Irs2 mRNA levels by 110, 160, 30, and 60% in the liver, respectively, and increased Irs1 by 80% in the muscle. Green tea extract (2 g) increased Glut4, Gsk3b, and Pik3cb mRNA levels by 90, 30, and 30% but decreased Shc1 by 60% in the liver and increased Glut2, Glut4, Shc1, and Sos1 by 80, 40, 60, and 50% in the muscle. This study shows that green tea extract at 1 or 2 g/kg diet regulates gene expression in the glucose uptake and insulin signaling pathway in rats fed a fructose-rich diet.     

Comparison of tick resistance of crossbred Senepol × Limousin to purebred Limousin cattle

The comparison of resistance to natural tick infestation by Rhipicephalus microplus (Canestrini, 1887) of crossbred Senepol?×?Limousin and purebred Limousin cattle was investigated. The Senepol breed, originated from St Croix Island in the Caribbean is considered as a Bos taurus breed adapted to tropical conditions. Despite its B. taurus genetic background, it is believed to have a good tick resistance, but this resistance has never been assessed previously. Tick counts under natural infestation were carried out to investigate the difference of susceptibility between crossbred Senepol?×?Limousin and purebred Limousin cattle. Mixed-effect models were used to assess the effect of the breed on the number of ticks. Results show that Senepol?×?Limousin are five times less infested by ticks than purebred Limousin. These results underline the opportunity to use Senepol cattle for crossing with susceptible B. taurus breeds in tick infested areas, to combine tick resistance with beef production abilities.