On some physics to consider in numerical simulation of erosive cavitation

This paper discusses several mechanisms in erosive cavitation, which are all important to capture, and study, when assessing the risk of erosion. In particular we introduce the concept of primary and secondary cavitation in order to put emphasis on a particular class of mechanisms: cavitation created in the secondary flow field governed by, e.g., a shedding or collapse of a primary created cavity. These secondary cavities are almost always erosive and have previously not been well described in the literature. The role of cloud cavitation is partly reconsidered and a hypothesis for development of vortex group cavitation, a type of secondary cavitation, is presented. An underlying part of the discussion is how the described cavitation mechanisms influence numerical simulation of cavitation nuisance.http://deepblue.lib.umich.edu/bitstream/2027.42/84223/1/CAV2009-final180.pd

Nutritive value of sun-dried common reed (Phragmites australis) leaves and its effect on performance and carcass characteristics of the growing rabbit

[EN] The nutritive value and potential use of sun-dried common reed (Phragmites australis) leaves (CRL), for growing rabbits was studied by comparing 3 diets (regression method) containing an increasing incorporation rate of CRL: 0% (control, CRL0), 15% (CRL15) and 30% (CRL30) in substitution for the control diet (356 g neutral detergent fibre (NDF) and 197 g crude protein (CP)/kg). Three groups of 37 rabbits (individually caged) were fed the 3 diets ad libitum from weaning (35 d, mean weight: 722±142 g) to 77 d of age. The faecal digestibility of the diets was measured between 42 and 46 d of age in 10 rabbits per group. CRL can be considered high-fibre roughage, as it contained 64% of NDF (38% of ADF and 10% ADL) and 10.2% of CP. The digestible energy (DE) content of CRL calculated by regression was null (–1.8±0.29 MJ/kg as fed). CP digestibility reached 29%, corresponding to a digestible crude protein concentration of 29.0±5.6 g/kg as fed basis. The fibre digestibility was reduced with CRL incorporation. Dietary incorporation of CRL impaired the rabbit growth (34.2 vs. 31.5 g/d during the period 35-77 d without CRL or with CRL (CRL15 and CRL30), respectively; P=0.002). Consequently, feed conversion was impaired with the high incorporation rate in feed (30%). Health status or main slaughter traits were not affected by CRL incorporation rate. Thus, the sun-dried common reed leaves had a poor nutritive value for growing rabbits and it can be considered a high-fibre feedstuff, interesting to supply low digested fibres (cellulose) and lignin.The authors thank Belaidi-Gater N., Louchami Y., Slimani M., Selmani K. Djaroun T., Haddad M. and Yahi K. for their assistance in the experimental trial.This work was partially financed by the CMEP-Tassili project (05 MDU 667).Kadi, S.; Ouendi, M.; Bannelier, C.; Berchiche, M.; Gidenne, T. (2018). Nutritive value of sun-dried common reed (Phragmites australis) leaves and its effect on performance and carcass characteristics of the growing rabbit. World Rabbit Science. 26(2):113-121. https://doi.org/10.4995/wrs.2018.5217SWORD113121262Abdel-Samee A.M., El-Masry K.A. 1992. Effect of drinking natural saline well water on some productive and reproductive performance of California and New-Zealand White rabbits maintained under north Sinai conditions. Egypt. J. Rabbit Sci., 2, 1-11.AFNOR. 1997. Norme Française homologuée, Aliments des animaux. Détermination séquentielle des constituants pariétaux. Méthode par traitement aux détergents neutre et acide et à l'acide sulfurique. AFNOR publ., Paris. NF V 18-122, 11.Allirand J.M., Gosse G. 1995. An above-ground biomass production model for a common reed (Phragmites communis Trin.) Stand. Biomass Bioenerg., 9: 441-448. https://doi.org/10.1016/0961-9534(95)00042-9Baldantoni D., Ligrone R., Alfani A. 2009. Macro- and trace-element concentrations in leaves and roots of Phragmites australis in a volcanic lake in Southern Italy. J. Geochem. Explor., 101: 166-174. https://doi.org/10.1016/j.gexplo.2008.06.007Baran M., Váradyová Z., Krácmar S., Hedbávny J. 2002. The common reed (Phragmites australis) as a source of roughage in ruminant nutrition. Acta Vet. Brno.,71: 445-449. https://doi.org/10.2754/avb200271040445Blasco A., Ouhayoun J. 1996. Harmonization of criteria and Terminology in rabbit meat research. Revised proposal. World Rabbit Sci., 4: 93-99. https://doi.org/10.4995/wrs.1996.278Bonanno G. 2011. Trace element accumulation and distribution in the organs of Phragmites australis (common reed) and biomonitoring applications. Ecotox. Environ. Saf., 74: 1057-1064. https://doi.org/10.1016/j.ecoenv.2011.01.018Cheeke P. R. 1986. Potentials of Rabbit Production in Tropical and Subtropical Agricultural Systems. J. Anim. Sci., 63: 1581-1586. https://doi.org/10.2527/jas1986.6351581xCilliers S.C., Angel C.R. 1999. Basic Concepts and Recent Advances in Digestion and Nutrition. In: Deeming D.C. (Eds.), The Ostrich: Biology, Production and Health, CABI, 105-128.De Blas, J.C., Rodriguez J.M., Santoma G., Fraga M.J. 1984. The nutritive value of feeds for growing fattening rabbits. 1. Energy evaluation. J. Appl. Rabbit Res., 7: 72-74.De Blas J.C., Villamide M.J., Carabaño R. 1989. Nutritive value of cereal by-products for rabbits. 1. Wheat straw. J. Appl. Rabbit Res. 12: 148-151.De Blas C., Mateos G.G. 2010. Feed formulation. In: De Blas, C., Wiseman, J. (Eds.), Nutrition of the rabbit, CABI, 222-232. https://doi.org/10.1079/9781845936693.0222De la Cruz, A.A. 1983. Caloric values of marsh biota. Mississippi -Alabama Sea Grant Consortium Pub1. No. MASGP -83-006. Ocean Springs, Mississippi. 32 p.Deshmukh S.V., Pathak N.N., Johari S.B. 1990. A note on the nutritional evaluation of pre-flowering oat (Avena sativa) forage for rabbits. J. Appl. Rabbit Res. 13: 93-94.Eiben Cs., Végi B., Virág Gy., Gódor-Surmann K., Maró A., Odermatt M., Zsédely E., Tóth T., Schmidt J. 2010. Effect of different dietary ratios of sunflower and linseed oils on growth and carcass traits of rabbits. Livest. Sci., 131: 15-22. https://doi.org/10.1016/j.livsci.2010.02.017EGRAN 2001. Technical note: Attempts to harmonise chemical analyses of feeds and faeces, for rabbit feed evaluation. World Rabbit Sci., 9: 57-64. https://doi.org/10.4995/wrs.2001.446Fernández-Carmona J., Blas E., Pascual J.J., Maertens L., Gidenne T., Xiccato G., García J. 2005. Recommendations and guidelines for applied nutrition experiments in rabbits. World Rabbit Sci., 13: 209-228. https://doi.org/10.4995/wrs.2005.516García J., Carabaño R., de Blas C. 1999. Effect of fiber source on cell wall digestibility and rate of passage in rabbits. J. Anim. Sci., 77: 898-905.García J., Nicodemus N., Carabaño R., de Blas C. 2002. Effect of inclusion of defatted grape seed meal in the diet on digestion and performance of growing rabbits. J. Anim. Sci., 80: 162-170. https://doi.org/10.2527/2002.801162xGarcía J., Villamide M.J., De Blas J.C. 1996. Energy, protein and fibre digestibility of sunflower hulls, olive leaves and NAOHtreated barley straw for rabbits. World Rabbit Sci., 4: 205-209. https://doi.org/10.4995/wrs.1996.296Gidenne T. 1992. Effect of fibre level, particle size and adaptation period on digestibility and rate of passage as measured at the ileum and in the faeces in the adult rabbit. Brit. J. Nutr., 67, 133-146. https://doi.org/10.1079/BJN19920015Gidenne T., Scalabrini F., Marchais C. 1991. Adaptation digestive du lapin à la teneur en constituants pariétaux du régime. Ann. Zootech., 34: 73-84. https://doi.org/10.1051/animres:19910203Gidenne T., Carabaño R., García J., De Blas C. 2010a. Fibre Digestion. In: De Blas, C., Wiseman, J. (Eds.), Nutrition of the rabbit, CABI, 66-82. https://doi.org/10.1079/9781845936693.0066Gidenne T., García J., Lebas F. Licois D. 2010b. Nutrition and Feeding Strategy: Interactions with Pathology. In: De Blas, C., Wiseman, J. (Eds.), Nutrition of the rabbit, CABI,179-199. https://doi.org/10.1079/9781845936693.0179Gidenne T., Lebas F. 2002. Role of dietary fibre in rabbit nutrition and in digestive troubles prevention. 2nd Rabbit Congress of the America, Habana City, Cuba, June 19-22, 2002, 47-59.Guemour D., Bannelier C., Della A., Gidenne T. 2010. Nutritive value of sun-dried grape pomace, incorporated at a low level in complete feed for the rabbit bred under magrebian conditions. World Rabbit Sci., 18: 17-25. https://doi.org/10.4995/WRS.2010.18.03Gowda N.K.S., Ramana J.V., Prasad C.S., Singh K. 2004. Micronutrient content of certain tropical conventional and unconventional feed resources of southern India. Trop. Anim. Health Prod., 36: 77-94.Habeeb, A.A.M., Marai, I.F.M., El-Maghawry, A.M. and Gad, A.E. 1997. Physiological response of growing rabbit to different concentrations of salinity in drinking water under winter and hot summer conditions. Egyp. J. Rabbit Sci., 7: 81-94.Hernández P., DalleZotte A. 2010. Diet and Rabbit Meat Quality. In: De Blas, C., Wiseman, J. (Eds.), Nutrition of the rabbit, CABI, 163-178. https://doi.org/10.1079/9781845936693.0163Ho Y.B. 1981. Mineral composition of Phragmites australis in Scottish lochs as related to eutrophication. I. Seasonal changes in organs. Hydrobiologia,85: 227-237. https://doi.org/10.1007/BF00017612International Standarization Organization. 1998. Animal feeding stuffs animal products, and faeces or urine - Determination of gross calorific value. Bomb calorimeter method. Norme international ISO 9831. Available at: http://www.iso.org. Accessed May 2018.International Standarization Organization. 1999. Animal feeding stuffs Determination of moisture and other volatile matter content. Norme international ISO 6496. Available at: http://www.iso.org. Accessed May 2018.International Standarization Organization. 2002. Animal feeding stuffs. Determination of crude ash. Norme international ISO 5984 Available at: http://www.iso.org. Accessed May 2018.International Standarization Organization. 2006. Animal feeding stuffs Determination of amylase-treated neutral detergent fibre content (aNDF). Norme international ISO 16472. Available at: http://www.iso.org. Accessed May 2018.International Standarization Organization. 2008. Animal feeding stuffs Determination of acid detergent fibre (ADF) and acid detergent lignin (ADL) contents. Norme international ISO 13906. Available at: http://www.iso.org. Accessed May 2018.International Standarization Organization. 2009. Food products. Determination of the total nitrogen content by combustion according to the Dumas principle and calculation of the crude protein content. Part 2: Cereals, pulses and milled cereal products. Norme international ISO 16634-2. Available at: http://www.iso.org. Accessed May 2018.Kadi S.A., Djellal F., Berchiche M. 2008. Commercialisation of rabbit's meat in Tizi-Ouzou area, Algeria. In Proc.: 9th World Rabbit Congress, June 10-13, 2008, Verona, Italy.Kadi S.A., Guermah H., Bannelier C., Berchiche M., Gidenne T. 2011. Nutritive value of sun-dried Sulla (Hedysarum flexuosum), and its effect on performance and carcass characteristics of the growing rabbit. World Rabbit Sci., 19: 151-159. https://doi.org/10.4995/wrs.2011.848Kiviat E., Hamilton E. 2001. Phragmites use by Native North Americans. Aquat. Bot., 69: 341-357.https://doi.org/10.1016/S0304-3770(01)00147-4Lakabi-Ioualitene D., Lounaouci-Ouyed G, Berchiche M., Lebas F., Lamothe L. 2008. The effects of the complete replacement of barley and soybean meal with hard wheat by products on diet digestibility, growth and slaughter traits of local Algerian rabbit population. World Rabbit Sci., 16: 99-106. https://doi.org/10.4995/wrs.2008.632Lavoie C. 2008. Envahissement du roseau commun le long des corridors autoroutiers: état de situation, causes et gestion. Rapport final Réalisé pour le compte du ministère des Transports du Québec. 160 p. Lebas F. 1975. Influence de la teneur en énergie de l'aliment sur les performances de croissance chez le lapin. Ann. Zootech., 24: 281-288. https://doi.org/10.1051/animres:19750211Lebas F., Coudert P., De Rochambeau H., Thébault R.G. 1996. Le lapin, élevage et pathologie. FAO. Rome, 223 p.Lebas F., Djago A.Y. 2001. Valorisation alimentaire de la paille par le lapin en croissance. 9èmeJourn. Rech. Cunicole, Paris, 28-29 novembre 2001: 77- 80.Lounaouci-Ouyed G., Lakabi D., Berchiche M., Lebas F. 2009. Effets d'un apport de paille en complément d'un aliment granulé pauvre en fibres sur la digestion, la croissance et le rendement à l'abattage de lapins de population locale algérienne. 13èmes Journ. Rech. Cunicole, 17-18 novembre 2009, Le Mans, France.Lounaouci-Ouyed G., Berchiche M., Gidenne T. 2011. Effets de l'incorporation de taux élevés (50 à 60%) de son de blé dur sur la mortalité, la digestibilité, la croissance et la composition corporelle de lapins de population blanche dans les conditions de production algériennes. 14ème Journ. Rech. Cunicole, 22-23 novembre 2009, Le Mans, France: 13-16.Maertens L. 1992. Rabbit nutrition and feeding: a review of some recent developments. J. Appl. Rabbit Res., 15: 889-913.Maertens L., Van Herck A. 2001. Digestibilité de quelques matières premières couramment utilisées dans l'alimentation du lapin. 9émes Journ. Rech. Cunicole, Paris, 28-29 novembre 2001: 81-84.Maertens L., Pérez J.M., Villamide M., Cervera C., Gidenne T., Xiccato G. 2002. Nutritive value of raw materials for rabbits: EGRAN tables 2002. World Rabbit Sci., 10: 157-166. https://doi.org/10.4995/wrs.2002.488Majchrzak Y. 1992. Evolution des communautés végétales de marais tourbeux soumises au pâturage de bovins et d'équins. Application pour la gestion conservatoire d'une zone humide, le marais de Lavours (Ain, France). PhD Thesis, Grenoble I university, France.Marks M., Lapin B., Randall J. 1994. Phragmites australis (P. communis): threats, management, and monitoring. Nat. Area. J., 14: 285-294.Motta Ferreira W., Fraga M.J., Carabaño R. 1996. Inclusion of grape pomace, in substitution for alfalfa hay, in diets for growing rabbits. Anim. Sci., 63: 167-174. https://doi.org/10.1017/S135772980002840XNicodemus N., Carabaño R., García J., Méndez J., de Blas J.C. 1999. Performance response of lactating and growing rabbits to dietary lignin content. Anim. Feed Sci. Technol., 80: 43-54. https://doi.org/10.1016/S0377-8401(99)00042-5Nicodemus N., García J., Carabaño R., de Blas C. 2002. Effect of the inclusion of sunflower hulls in the diet on performance, disaccharidase activity in the small intestine and caecal traits of growing rabbits. Anim. Sci., 75: 237-243. https://doi.org/10.1017/S1357729800052991Nikolajevskij V.G. 1971. Research into the biology of the common reed (Phragmites communis Trin.) in the U.S.S.R. Folia Geobot. Phytotx., 6: 221-230.Papadomichelakis G., Zoidis E., Fegeros K. 2012. Dietarily induced changes in liver composition and weight of fattening rabbits. Livest. Sci., 144: 190-196. https://doi.org/10.1016/j.livsci.2011.11.012Pérez J.M., Lebas F., Gidenne T., Maertens L., Xiccato G., Parigi-Bini R., DalleZotte A., Cossu M.E., Carazzolo A., Villamide M.J., Carabaño R., Fraga M.J., Ramos M.A., Cervera C., Blas E., Fernàndez-Carmona J., Falcão-e-Cunha L., Bengala Freire J. 1995. European reference method for in-vivo determination of diet digestibility in rabbits. World Rabbit Sci., 3: 41-43. https://doi.org/10.4995/wrs.1995.239Schaller J., Brackhage C., Gessner M.O., Baüker E., GertDudel E. 2011. Silicon supply modifies C:N:P stoichiometry and growth of Phragmites australis. Plant Biology., 14: 392-396https://doi.org/10.1111/j.1438-8677.2011.00537.xSun Z., Zhou D., Ferreira L.M.M., Zhong Q., Lou Y. 2008. Diet composition, herbage intake and digestibility in Inner Mongolian Cashmere goats grazing on native Leymus chinensis plant communities. Livest. Sci., 116: 146-155. https://doi.org/10.1016/j.livsci.2007.09.018Tao Z.Y., Li F.C. 2006. Effects of dietary neutral detergent fibre (NDF) on production performance, nutrient utilization, caecum fermentation and fibrolytic activity in 2-3 month New Zealand rabbits. J. Anim. Physiol. Anim. Nutr., 90, 467-473.https://doi.org/10.1111/j.1439-0396.2006.00628.xUchytil R.J. 1992. Phragmites australis. 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Early diagnosis and management of traumatic dura tear with brachial plexus injury without spinal lesions in childhood

Although the dura is a thick membrane, it could be severed in spine surgery and less frequently by a traumatism (7,8,10); in this case, it is usually accompanied with bone or ligamentous injury (2). Rare cases are reported of a traumatic dura tear without spinal lesion and would suspect in the first place a brachial plexus injury (2,8). Dura tears are rarely seen in childhood (3). We report a case of early diagnosis of dura tear in brachial plexus injury without bone or ligamentous lesions on a child of 4 years old and we discuss the diagnostic and treatment modalities

The effects of the complete replacement of barley and soybean meal with hard wheat by-products on diet digestibility, growth and slaughter traits of a local Algerian rabbit population

[EN] Eighty one rabbits were used to study the utilisation of hard wheat by-products on the growth of rabbits from a local Algerian population. At weaning (28 d, 501±99 g), the animals were individually caged and received ad libitum one of the three experimental diets for 49 d. The control diet included 26% wheat bran (W26: control diet), alfalfa, bar- ley and soybean meal. The two other diets were formulated by substituting barley and soybean meal with hard wheat by-products, and contained 60% (W60) or 67% (W67) of these by-products (50 or 57% bran and 10% middling). On average, diets contained 11.8% crude fibre and crude protein decreased from 18.3 (W26) to 16.1% (W67). Growth traits and slaughter performances were recorded. Another group of thirty animals was used to determine dietary nutrient di- gestibility from 42 to 46 d of age. Dry matter digestibility and digestible energy content were lower in the W60 and W67 diets than in the control diet (W26) (71.3 and 71.5% vs. 74.9%, and 11.9 and 11.9 vs. 12.5 MJ/kg, respectively; P<0.01). In contrast, crude fibre digestibility was lower in W26 (21.9%) than in the other two diets (29.6 and 32.2% for W60 and W67, respectively; P<0.01). The growth rates were similar for all three groups (28.0, 27.1 and 26.0 g/d for W26, W60 and W67) as were the feed conversion ratios (3.14, 3.17 and 3.10, respectively). Dressing out percentage (66.4±2.0% on average for the cold carcass) was not affected by the amount of wheat by-products in the diet. The total mortality rate was high (23%), probably corresponding to the low crude fibre content of the three experimental diets, but was not connected to the amount of wheat by-products.Lakabi-Ioualitene, D.; Lounaouci-Ouyed, G.; Berchiche, M.; Lebas, F.; Fortun-Lamothe, L. (2010). The effects of the complete replacement of barley and soybean meal with hard wheat by-products on diet digestibility, growth and slaughter traits of a local Algerian rabbit population. World Rabbit Science. 16(2). doi:10.4995/wrs.2008.63216

Reproductive performance of male rabbits of algerian local population

[EN] A total of 267 rabbit does and 46 bucks from a local Algerian population were controlled during 6 generations (from G0 to G5) at the experimental farm of the University of Tizi-Ouzou. Natural mating was used and 1412 presentations were analysed. Reproductive and growing performance were analysedtaking into account the effect of the buck, its age, the generation, the season of mating (or kindling) and the physiological status of does at the moment of the mating. The buck influenced the acceptance rate(P<0.001), kindling rate (P=0.032), litter size at birth and at weaning (P<0.001), litter weight at birth (P<0.001)and at weaning (P=0.034), the mean weaning weight (P=0.018) and consequently the ponderal productivity at weaning (weight of rabbits produced at weaning/mating, P<0.001). Nevertheless, the ponderal productivity was also influenced by the age of bucks, the generation, the season and the physiological status of does at the moment of mating. The highest acceptation rate was recorded in autumn in non lactating does (primiparous and multiparous). Productivity was higher for bucks 5-10 mo old but decreased thereafter.Productivity was higher in spring, particularly for multiparous and lactating does and highly varied with the generation, evidencing the importance of environmental conditions.Dj, C.; M, T.; N, Z.; M, B. (2013). Reproductive performance of male rabbits of algerian local population. World Rabbit Science. 21(2):91-99. doi:10.4995/wrs.2013.1173.SWORD919921

CCR2 Acts as Scavenger for CCL2 during Monocyte Chemotaxis

<div><h3>Background</h3><p>Leukocyte migration is essential for effective host defense against invading pathogens and during immune homeostasis. A hallmark of the regulation of this process is the presentation of chemokines in gradients stimulating leukocyte chemotaxis via cognate chemokine receptors. For efficient migration, receptor responsiveness must be maintained whilst the cells crawl on cell surfaces or on matrices along the attracting gradient towards increasing concentrations of agonist. On the other hand agonist-induced desensitization and internalization is a general paradigm for chemokine receptors which is inconsistent with the prolonged migratory capacity.</p> <h3>Methodology/Principal Findings</h3><p>Chemotaxis of monocytes was monitored in response to fluorescent CCL2-mCherry by time-lapse video microscopy. Uptake of the fluorescent agonist was used as indirect measure to follow the endogenous receptor CCR2 expressed on primary human monocytes. During chemotaxis CCL2-mCherry becomes endocytosed as cargo of CCR2, however, the internalization of CCR2 is not accompanied by reduced responsiveness of the cells due to desensitization.</p> <h3>Conclusions/Significance</h3><p>During chemotaxis CCR2 expressed on monocytes internalizes with the bound chemoattractant, but cycles rapidly back to the plasma membrane to maintain high responsiveness. Moreover, following relocation of the source of attractant, monocytes can rapidly reverse their polarization axis organizing a new leading edge along the newly formed gradient, suggesting a uniform distribution of highly receptive CCR2 on the plasma membrane. The present observations further indicate that during chemotaxis CCR2 acts as scavenger consuming the chemokine forming the attracting cue.</p> </div

An Evolutionarily Conserved Arginine Is Essential for Tre1 G Protein-Coupled Receptor Function During Germ Cell Migration in Drosophila melanogaster

BACKGROUND: G protein-coupled receptors (GPCRs) play central roles in mediating cellular responses to environmental signals leading to changes in cell physiology and behaviors, including cell migration. Numerous clinical pathologies including metastasis, an invasive form of cell migration, have been linked to abnormal GPCR signaling. While the structures of some GPCRs have been defined, the in vivo roles of conserved amino acid residues and their relationships to receptor function are not fully understood. Trapped in endoderm 1 (Tre1) is an orphan receptor of the rhodopsin class that is necessary for primordial germ cell migration in Drosophila melanogaster embryos. In this study, we employ molecular genetic approaches to identify residues in Tre1 that are critical to its functions in germ cell migration. METHODOLOGY/PRINCIPAL FINDINGS: First, we show that the previously reported scattershot mutation is an allele of tre1. The scattershot allele results in an in-frame deletion of 8 amino acids at the junction of the third transmembrane domain and the second intracellular loop of Tre1 that dramatically impairs the function of this GPCR in germ cell migration. To further refine the molecular basis for this phenotype, we assayed the effects of single amino acid substitutions in transgenic animals and determined that the arginine within the evolutionarily conserved E/N/DRY motif is critical for receptor function in mediating germ cell migration within an intact developing embryo. CONCLUSIONS/SIGNIFICANCE: These structure-function studies of GPCR signaling in native contexts will inform future studies into the basic biology of this large and clinically important family of receptors

Evaluation of breeding performance of a local Algerian rabbit population raised in the Tizi-Ouzou area (Kabylia)

A total of 287 females of a local Kabylian population of rabbits were studied at the University of Tizi-Ouzou (Algeria) over 6 years. The females were mated for the first time at the age of 4.5 months and remated 10-12 days after parturition. The females were characterized by a medium to small adult weight (2.81±0.38 kg) and a rather low prolificacy at birth and weaning (7.2±2.5 total born, 6.1±3.0 born alive and 5.4±2.3 weaned). Based on the registration of 1377 mating attempts, acceptance of mating and conception rates were 74.3±3.8% of presented does and 73.3±4.3% of mated does respectively. The Algerian hot summer season did not seem to affect parameters of practical importance such as fertility or litter size at weaning. The only significant effect (P<0.01) was a reduction of litter weight at weaning (-13%) compared with the average of the 3 other seasons (2070 vs 2368 g at 28 days). Acceptance and conception rates were not significantly affected by mating number. At first parturition, total number of kits (6.6/litter) was significantly lower than that of multiparous does (7.3 to 7.4), and individual birth weight of first litter kits was 10% lower than that observed for subsequent litters (51.4 g on average). On the other hand, it must be emphasised that for this sample of the Kabylian population, the kit's individual weight at weaning did not vary significantly with parturition number. Birth to weaning mortality was the lowest for parturition of rank 4 and more (9.8% vs 14.4 to 16.9% for previous ones).Zerrouki, N.; Bolet, G.; Berchiche, M.; Lebas, F. (2005). Evaluation of breeding performance of a local Algerian rabbit population raised in the Tizi-Ouzou area (Kabylia). World Rabbit Science. 13(1):29-37. doi:10.4995/wrs.2005.531SWORD293713

SUPPLÉMENTATION EN MÉTHIONINE DUN ALIMENT A BASE DE FÉVEROLE :EFFETS SUR LA CROISSANCE, LE RENDEMENT A L'ABATTAGE ET LA COMPOSITION DE LA CARCASSE CHEZ LE LAPIN

[EN] Five groups of twenty rabbits received from 5 to 11 weeks of age, 0ne of 5 diets based on horse bean (Ascott variety, 36 %) supplemented or not with pure dl-meth1onine in order to obtain the following final levels of sulphur amino acids (SAA) : 0.37 % - 0.47 % - 0.57 % - 0.62 % or 0.67 %. On average the diet's protein content was 16.9% as fed, and the crude fiber level 12.1 %. Nutrients digestibility was measured with the 0.62 % SAA diet: nitrogen 70.3 %, crude fiber 18.3 %, energy 68,7 %. The digestible energy content was 2670 kcal/kg as fed. The lowest level of SAA (0.37%) reduced significatively the daily growth rate (33.7 g/day). The highest one was observed with 0.62 % SAA: 40.8 g/day, but differences between the 0.47 % to 0.67 % SAA dlets were not significant. The feed efficiency was not affected by the diet's SAA level. The slaughter rate increased with the diet's SAA content, from 58.2 % to 60.1 %. As proportions of the whole carcass, liver, hind legs or kidney fat weights were not affected by the diet's SAA content. The same was observed for the hind leg meat-to-bone ratio. According to the authors, the SAA mínimum level is 0.47 % and the optimum 0.62 %, for diets with the digestible energy and protein contents employed in this expenment.[FR] Cent lapins Néo-Zélandais blanc répartis en 5 lots ont re9u entre 5 et 11 semaines d'age, /'un des 5 aliments contenant 36 % de féverole (variété Ascott), supplémentés ou non avec de la di méthionine, de maniere a contenir 0,37 % - 0,47 % - 0,57 % - 0,62 % ou 0,67 % d'acides aminés soufrés (AAS). Les aliments contenaient en moyenne 16,9 % de protéines et 12, 1 % de ce/Ju/ose brute. Les CUDa estimés pour l'aliment 4 (0,62 % d'AAS) sont de 70,3 % pour /'azote, 18,3 % pour la ce/Ju/ose brute et 68, 7 % pour l'énergj_e conduisant a une teneur moyenne en énergie digestible (ED) de 2670 kcal/kg. Une teneur de 0,37 % d'AAS ra7entit significativement la vitesse de croissance. Les meilleures performances de croíssance (40,8 g/j) sont obtenues avec 0,62 % d'AAS, mais les différences entre les lots contenant 0,47 et 0,67 % d'AAS ne sont pas significatives. L'efficacité alimentaire n'est pas modifiée par l'incorporation de méthionine. Le rendement a l'abattage (carcasse froide sans manchons) est accru proportionnel/ement au taux d'AAS, il varie de 58,2 a 60, 1 %. En pourcentage de la carcasse, le poids du foie, du membre postérieur et du gras périrénal ne sont pas modifiés par l'addition de méth1onine. De meme, le rapport muse/e sur os du membre postérieur ne varíe pas de maniere significative entre lots. Un taux de 0,47 % d'AAS semble etre le mínimum acceptable tandis que 0,62 % semble etre l'optimum pour le taux azoté et la teneur en ED expérimentés.Berchiche, M.; Lebas, F. (1994). SUPPLÉMENTATION EN MÉTHIONINE DUN ALIMENT A BASE DE FÉVEROLE :EFFETS SUR LA CROISSANCE, LE RENDEMENT A L'ABATTAGE ET LA COMPOSITION DE LA CARCASSE CHEZ LE LAPIN. World Rabbit Science. 2(4). doi:10.4995/wrs.1994.229SWORD2