Étude d'un gène de nanisme lié au sexe chez la poule. V. – Composition corporelle in vivo

International audienc

Sélection sur la vitesse de croissance post-sevrage chez le lapin

On a effectué une expérience de sélection massale sur la vitesse de croissance entre le sevrage (30 j) et 77 j dans une souche de lapin. La souche sélectionnée se composait de 12 mâles et 60 femelles pendant les 4 premières générations puis de 8 mâles et 40 femelles pendant les 4 suivantes. La souche témoin se composait aussi de 8 mâles et de 40 femelles. On a réalisé une intensité de sélection de 0,95. La vitesse de croissance post-sevrage est améliorée de 6,9 g pour 8 générations, soit un progrès de 0,83 g par génération. L’héritabilité réalisée est égale à 0,23. Pour une augmentation d’un g de la vitesse de croissance post-sevrage, on observe une diminution de 0,10 du nombre de lapins vivants à la naissance par portée. Simultanément, le nombre de lapins vivants à 77 j produits par femelle mise à la reproduction a tendance à diminuer. Cette réduction de la fitness est due principalement à une diminution du nombre de femelles ayant fait au moins une portée avec un lapin vivant à 77 j.A selection experiment was made on the growth rate between weaning (30 days) and 77 days in a rabbit strain. There were 12 bucks and 60 does in the selected strain during the first4 generations, then 8 bucks and l,0 does during the next 4 generations. There were 8 bucks and 40 does in the control strain. Selection intensity was 0.95. The response in post-weaning growth rate was 6.9 g after 8 generations, i.e. 0.83 g per generation. The realized heritability was 0.23. The increase in post-weaning growth rate was accompanied b an increase in 77-days body weight (58 g) and by a decrease in litter size at birth (-0.10) At the same time, the number of rabbits alive at 77 days per reproductive doe decreased. The main reason for the decrease of fitness was a decrease in the number of does with at least one rabbit alive at 77 days

Efficacy of essential oil mouthwash with and without alcohol: a 3-Day plaque accumulation model

<p>Abstract</p> <p>Background</p> <p>The aim of this study was to evaluate the antiplaque effect of a new alcohol free essential oil mouthwash with respect to a control of an essential oil with alcohol mouthwash, using an <it>in vivo </it>plaque regrowth model of 3-days.</p> <p>Methods</p> <p>The study was designed as a double-masked, randomized, crossover clinical trial, involving 30 volunteers to compare two different essential oil containing mouthwashes, during a 3-day plaque accumulation model. After receiving a thorough professional prophylaxis at the baseline, over the next 3-days each volunteer refrained from all oral hygiene measures and had two daily rinses with 20 ml of the test mouthwash (alcohol free essential oil) or the control mouthwash (essential oil with alcohol). At the end of the each experimental period, plaque was assessed and the panelists filled out a questionnaire. Each subject underwent a 14 days washout period and there was a second allocation.</p> <p>Results</p> <p>The essential oil mouthwash with ethanol shows a better inhibitory effect of plaque regrowth in 3-days than the mouthwash test with only essential oil in the whole mouth (plaque index = 2.18 against 2.46, respectively, p < 0.05); for the lower jaw (plaque index = 2.28 against 2.57, respectively, p < 0.05); for the upper jaw (plaque index = 2.08 against 2.35, respectively, p < 0.05); for the incisors (plaque index = 1.93 against 2.27, respectively, p < 0.05); and the canines (plaque index = 1.99 against 2.47, respectively, p < 0.05).</p> <p>Conclusion</p> <p>The essential oil containing mouthwash without alcohol seems to have a less inhibiting effect on the plaque regrowth than the traditional alcoholic solution.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov <a href="http://www.clinicaltrials.gov/ct2/show/NCT01411618">NCT01411618</a></p