Influence of age at weaning and nutritive value of weaning diet on growth performance and caecal traits in rabbits

[EN] To investigate the relationship between dietary nutrient concentration and weaning age on growth performance and caecal characteristics of rabbits, a trial was carried out on 64 litters (eight rabbits/litter) comparing two weaning ages (25 vs. 34 d) and two diets (HC: high concentrated and LC: low concentrated diet) offered to the kits from 18 to 34 d of age. At 34 d of age 54 animals per group were caged individually and all were fed the LC diet until 45 d of age. All animals were then fed a standard fattening diet (37% neutral detergent fiber, 3.4% ether extract and 18.0% crude protein on dry matter basis) until slaughter at 80 d. The digestibility trial was performed from 56 to 60 d of age on another group of 16 rabbits (8 per diet). During the experimental period (18-80 d of age), feed intake and animal weights were recorded. Caecal volatile fatty acids were measured at 45 and 80 d of age, while microbiological analysis was performed at 25 and 34 d on healthy suckling rabbits. Digestibility of dry matter, protein, neutral detergent fiber, fat and energy was higher in rabbits fed the HC diet (by 7.7, 7.4, 13.1, 26.7, 10.6%, respectively; P<0.001) than in those fed the LC diet. Growth rate and feed conversion ratio (FCR) from 18 to 34 d improved by 7.7 and 9.5% in rabbits fed HC in comparison to the LC diet, respectively (P¿0.061). Diet offered around weaning did not influence growth rate or FCR from 34 to 80 d of age. Rabbits weaned earlier increased feed intake (by 67.8%) from 25 to 34 d, but reduced growth rate (by 26.8%) compared to animals weaned at 34 d (P<0.001). Early weaning reduced live weight during the entire fattening period (P¿0.018), as well as the FCR (by 4%; P<0.001). Caecal pH was lower at 45 d of age in rabbits weaned at 25 d than in those weaned at 34 d (5.53 vs. 5.83; P=0.019). Treatments did not affect total caecal VFA concentration, but HC diet decreased caecal acetic concentration and increased butyric acid level compared to the LC diet at 45 d (P¿0.001). HC diet tended to reduce caecal counts of Enterobacteriacae (P=0.093), while it did not affect facultative anaerobic bacteria, E. Coli and Costridium spp. The LC diet increased at 25 d the number of Clostridium perfringens in comparison with the HC group at the same age and in comparison with animals fed both two diets at 34 d (P<0.001). The values of E. Coli and Enterobacteriaceae increased (P¿0.008) from 25 to 34 d of age, whereas that of Clostridium spp. decreased. Weaning at 25 d increased mortality from 18 to 34 d compared with rabbits weaned at 34 d (7.02 vs. 2.46%, P=0.017). However, during the fattening period (34-80 d) rabbits weaned earlier showed lower mortality (7.41 vs. 17.6%; P=0.024).This work has been realized within the CUNISVEZZ research project financed by the Agricultural Department of the Regione Lombardia as part of the 2004 research and development plan, d.g.r. 30/04/2004 n. VII/17326. The authors wish to thank Nicoletta Cesari for her technical assistance.Cesari, V.; Grilli, G.; Ferrazzi, V.; Toschi, I. (2009). Influence of age at weaning and nutritive value of weaning diet on growth performance and caecal traits in rabbits. World Rabbit Science. 17(4):195-205. https://doi.org/10.4995/wrs.2009.64419520517

Hilbert's 16th Problem for Quadratic Systems. New Methods Based on a Transformation to the Lienard Equation

Fractionally-quadratic transformations which reduce any two-dimensional quadratic system to the special Lienard equation are introduced. Existence criteria of cycles are obtained

Taxonomy and phylogeny of European Monochamus species: first molecular and karyological data

The worldwide distributed genus Monochamus Megerle, 1821 (Coleoptera Cerambicydae) comprises beetles that may become pests of economic importance in conifer stands in the Nearctic and Palearctic Regions. Besides direct damage due to the larval tunnelling habits, they have also been recognized as main vectors of the phytoparasitic nematode Bursaphelenchus xylophilus (Steiner & Buhrer, 1934) (Nematoda Aphelenchoididae). We analysed the complete mitochondrial cytochrome oxidase I gene and a fragment of the small subunit RNA gene sequences (1536 base pairs) in the five European species. These are: Monochamus galloprovincialis (Olivier, 1795), morphologically distinguished in two subspecies M. galloprovincialis galloprovincialis (Olivier, 1795) and M. galloprovincialis pistor (Germar, 1818); Monochamus sutor (Linneus 1758); Monochamus saltuarius (Gebler 1830); Monochamus sartor (Fabricius, 1787) and Monochamus urussovi (Fischer, 1806). For appropriate comparisons, also the Asiatic Monochamus alternatus Hope, 1842 and a Japanese M. saltuarius sample have been analysed. Both genes show an absolute identity between the two subspecies of M. galloprovincialis and a strong affinity between M. sartor and M. urussovi: the morphological subdivisions of the former taxon in two subspecies and of the latter in two entities of specific level are therefore not supported genetically. On the other hand, the Italian and the Japanese samples of M. saltuarius always cluster together in all trees, and for the remaining taxa, no doubt about their rank of specific differentiation emerges from present analyses. From a phyletic point of view, tree topology indicates the Japanese M. alternatus as the most differentiated taxon and the Euroasiatic M. saltuarius as basal to all other strictly European entities. Chromosome analyses show that the diploid autosomal complement ranges from 18 in M. saltuarius to 20 in M. galloprovincialis, and 22 in M. sartor, but a XX–Xyp sex determining system is shared by all analysed taxa. The M. saltuarius karyotype appears as the most primitive from which the others may be derived through Robertsonian fissions. Karyological data therefore agree with molecular analyses in indicating a basal position of Euroasiatic M. saltuarius with respect to the group of European Monochamus taxa; among these, M. galloprovincialis and M. sartor represent two clearly diverging evolutionary units. Furthermore, karyotype analyses substantiate molecular conclusions about the identity between M. galloprovincialis galloprovincialis and M. galloprovincialis pistor. Zusammenfassung Die weltweit verbreitete Gattung Monomachus Megerle, 1821 (Coleoptera, Cerambycidae) enthalt Kaferarten, die in den Nadelwaldern der nearktischen und palaarktischen Regionen zu wirtschaftlich bedeutenden Schadlingen werden konnen. Neben dem direkten Schaden durch die minierenden Larven sind sie auch als Hauptvektoren des Nematoden Bursaphelenchus xylophilus bekannt geworden. Wir haben das gesamte Gen der mitochondrialen Cytochromoxidase I und ein Stuck des ssRNA-Gens (1536 bp) der funf europaischen Arten (M. galloprovincialis, mit den zwei Unterarten M. g. galloprovincials und M. g. pistor, M. sutor, M. saltuarius, M. sartor und M. urossovi, sowie fur einen Vergleich auch von der asiatischen Art M. alternatus und aus dem japanischen Verbreitungsgebietes der Art M. saltuarius analysiert. Beide Gene erweisen sich fur die beiden Unterarten M. g. galloprovincials und M. g. pistor als vollkommen identisch und weisen auf eine nahe Verwandtschaft zwischen M. sartor und M. urossovi hin; die morphologische Unterteilung in die beiden Unterarten und die Auftrennung dieser beiden Spezies auf Artniveau wird also genetisch nicht unterstutzt. Auf der anderen Seite clustern die italienischen und die japanischen Stichproben von M. saltuarius in allen Dendrogrammen sehr eng, so das ihr Status als Art gegenuber den anderen Taxons nicht bezweifelt werden kann. Vom phylogenetischen Standpunkt beurteilt weist die Topologie der Baume darauf hin, das die japanische Art M. alternatus die am meisten abweichende Spezies und die eurasische Art M. saltuarius die ursprunglichste unter den streng europaischen Monomachus-Arten ist. Die Chromosomenanalyse ergibt, das die diploide Chromosomenzahl sich von 18 bei M. saltuarius auf 20 bei M. galloprovincialis und auf 22 bei M. sartor erhoht, das geschlechtsdeterminierende System aber bei allen Taxa gemeinsam dem Typ XX-Xyp entspricht. Der Karyotyp von M. saltuarius scheint der ursprunglichste zu sein, von dem die anderen durch Robertsonsche Fissionen abgeleitet werden konnen. Die karyologischen Daten stimmen auch mit den molekularen uberein, indem sie der eurasischen Art M. saltuarius eine, zu den europaischen Arten basale Position zuweisen. Unter diesen stellen die Arten M. galloprovincialis und M. sartor zwei deutlich divergierende evolutionare Einheiten dar. Auserdem bestatigen die karyotypischen Analysen die molekulare Schlusfolgerung, das die zwei Unterarten M. g. galloprovincials und M. g. pistor identisch sind

Effect of weaning age and diet on growth performance, caecal characteristics and potential pathogenetic microflora in rabbits

The aim of this study was to investigate the effect of age and diet at weaning on growth performances, caecal characteristics and development of potential pathogenetic microflora. The trial was carried out on 64 litters from 18 to 45 days of age comparing two weaning age (25 vs. 34 d) and two weaning diets (HF and LF) characterized, especially, by different energy, fat and starch concentration (HF: DE=11.5 MJ/kg, EE=6.2%, Starch=8.7%; LF: DE=10.1 MJ/kg DM, EE=3.1%, Starch=11.3%). At 45 d, early weaning determined a significant reduction of growth (1219 vs. 1282; P<0.01), although the solid feed intake resulted significantly higher, from 25 to 34 days of age, in early weaned rabbits (50.0 vs. 29.8 g/d; P<0.001). The age at weaning did not modify caecal traits, with the exception of pH value, that was lower in rabbits early moved to the mothers (5.53 vs. 5.83; P<0,05). Independently by age of weaning, the administration of diet HF promoted growth performance in rabbits at 45 d (1280 vs. 1222; P<0.01). Diet composition did not influence mortality rate at 34 days of age, while early weaning determined values significantly higher than those found in rabbits weaned later. The data of microbial analysis, carried out on 10 animals per diet (at 25 and 34 days of age), showed potential pathogenetic microflora development depended by the age of animal and was not affected by the composition of diets

Premartensitic transition driven by magnetoelastic interaction in bcc ferromagnetic Ni2MnGaNi_{2}MnGa

We show that the magnetoelastic coupling between the magnetization and the amplitude of a short wavelength phonon enables the existence of a first order premartensitic transition from a bcc to a micromodulated phase in $Ni_{2}MnGa$. Such a magnetoelastic coupling has been experimentally evidenced by AC susceptibility and ultrasonic measurements under applied magnetic field. A latent heat around 9 J/mol has been measured using a highly sensitive calorimeter. This value is in very good agreement with the value predicted by a proposed model.Comment: 4 pages RevTex, 3 Postscript figures, to be published in Physical Review Letter

egg quality and productive performance of laying hens fed different levels of skimmed milk powder added to a diet containing lactobacillus acidophilus

Abstract The current trial was carried out on a commercial poultry farm to study the effect of skim milk powder (SMP) added to a diet containing Lactobacillus acidophilus on performance and egg quality of laying hens from 20 to 49 wk of age. A total of 2,400 Hy-Line W-36 laying hens were housed in 600 unenriched cages (4 hens each) located over 4 tier levels. Animals were assigned to 1 of 3 experimental treatments (0, 3, and 4). The laying hens assigned to treatments 3 and 4 received a diet enriched respectively with 3 and 4% SMP, whereas the animals in treatment 0 were fed a diet without SMP. All diets, moreover, were supplemented with L. acidophilus D2/CSL. Hen performance was determined throughout the experimental period and egg quality was measured on 30 eggs per treatment every week. Results showed that productive performance in terms of egg production, egg weight, and feed conversion ratio was not influenced by SMP at 3 or 4% of the diet. Egg quality was significantly affected by SMP included at 3 or 4% of the diet. Eggs from treatments 3 and 4, in fact, displayed higher shell thickness than those from treatment 0 (

La Termogènesi als calorímetres per conducció: les transformacions sòlid-sòlid i les barreges líquides

Descrivim alguns mètodes d'obtenció de funcions de transferència associades a fenòmens reals i donem exemples de les termogènesis obtingudes en aquests casos. Els calorimètres amb molt bones característiques dinàmiques (&theta;n&sim;3Hz) són molt adequats per a l'estudi de fenòmens transitoris. En aquest treball presenten en primer lloc resultats relatius a la transformació &beta; &rarr; &gamma;' de l'aliatge Cu- Zn-Al. La transformació presenta un caràcter molt discontinu, una dissipació energètica important, i una excel•lent correlació amb l'emissió acústica generada durant el procés de transformació que permet donar una valoració qualitativa de les possibilitats calorimètriques de l'anàlisi entàlpica diferencial. En segon lloc presentem una anàlisi de les entalpies d'excés en les barreges líquides. Aquest estudi és molt interessant a baixes concentracions. L'ús de sistemes d'injecció permet assolir fraccions molars de solut xs\gtrsim 0.01. L'obtenció d'una funció de transferència correcta del sistema calorimètric i l'ús d'algorismes deconvolutius eficaços permet reduir la fracció molar a xs\gtrsim 0.001.This paper presents several methods to obtain transfer functions associated with power dissipations in actual phenomena and a few examples of the approximate thermogenesis obtained. On the one hand, calorimeters with extremely good dynamic characteristics (&theta;n&sim;3Hz) allow the study of structural transformations in solids. We present results concerning the martensitic transformation &beta; &rarr; &gamma;' of a Cu-Zn-Al alloy. They show the jerky character of the transformation very well correlated with acoustic emission patterns and an important energy 1iberation. This analysis gives an estimate of the posibilities of calorimetry within the field of Differential Enthalpic Analysis. On the other hand, an analysis of the properties of liquid mixtures at low concentrations is very interesting when carried out their excess enthalpies. Steady injection systems allow to reach solute molar fractions xs\gtrsim 0.01. We describe here the obtention of a correct transfer function. Now, the application of proper deconvolutive algorithms make it possible to work at so low concentrations as xs\gtrsim 0.001

Practice Recommendations for Diagnosis and Treatment of the Most Common Forms of Secondary Hypertension

The vast majority of hypertensive patients are never sought for a cause of their high blood pressure, i.e. for a \u2018secondary\u2019 form of arterial hypertension. This under detection explains why only a tiny percentage of hypertensive patients are ultimately diagnosed with a secondary form of arterial hypertension. The prevalence of these forms is, therefore, markedly underestimated, although, they can involve as many as one-third of the cases among referred patients and up to half of those with difficult to treat hypertension. The early detection of a secondary form is crucial, because if diagnosed in a timely manner, these forms can be cured at long-term, and even when cure cannot be achieved, their diagnosis provides a better control of high blood pressure, and allows prevention of hypertension-mediated organ damage, and related cardiovascular complications. Enormous progress has been made in the understanding, diagnostic\ua0work-up, and management of secondary hypertension in the last decades. The\ua0aim of this minireview is, therefore, to provide updated concise information on the screening, diagnosis, and management of the most common forms, including primary aldosteronism, renovascular hypertension, pheochromocytoma and paraganglioma, Cushing\u2019s syndrome, and obstructive sleep apnea