In vitro micrografting and its applications to fruit science

Improvements have been brought to in vitro micrografting. The breaking of dormancy by dipping the seeds of the rootstock in concentrated solutions of benzylaminopurine avoids having recourse to long stratification in the cold (60–120 days according to species). The initial pre-treatment of apices with cytokinin allows their development and facilitates later grafting. Moreover, adding DIECA to the cut sections avoids oxidation and, together with the insertion of a piece of agar between apex and rootstock, increases the success of micrografting. Finally, a special technique of in vivo micrografting of pretreated apices on young plants has been developed.Micrografting is commonly used to obtain peach trees free of Sharka and NRS viruses, and to study incompatibility mechanisms in heterografts, leading to an early diagnosis of incompatibilities.     

The behaviour of residues of benzoylprop-ethyl and its breakdown products in wheat

Samples of wheat grain and straw have been analysed from trials with the wild oat herbicide benzoylprop-ethyl ( I ) in several countries. Following recommended commercial treatments (application of 1.0–1.6 kg ha^?1 at Feekes growth stage G-J), total residues of I and its hydrolysis product N-benzoyl-N-(3,4-dichlorophenyl)-DL - alanine (free and conjugated) were low and in the majority of instances they were < 0.01 mg kg^?1 in samples of grain from the UK, although rather higher residues were detected in some grain samples from other countries. Residues in straw were higher, but normally did not exceed 2 mg kg^?1, and were rather variable, possibly as a result of differences in agricultural practice.     

Analysis of growth curve parameters of Gobra zebu females in Senegal

Summary Analysis of growth curve parameters was performed using body weight data collected from 1968 through 1980 at Dahra Research Station, Senegal. Month of birth had little or no effect on mature size and maturing rate. Females born from mid-wet through mid-dry seasons were likely to reach lighter mature weights than those born from mid-dry through mid-wet seasons. Year of birth affected both mature weight and maturing rate (P<0.01 and P<0.001 respectively). Sire had effects (P<0.05) on maturing rate and no effect on mature size. Genetic correlations between maturing rate and body weights at birth, weaning, 12 and 18 months were 0.45±0.51, –0.21±0.52, –0.61±0.57 and –0.76±0.51 respectively. Selection for maturing rate in Gobra females would be expected to decrease weaning and post-weaning weights. The least squares means of mature size and maturing rate were 398.83±45.81 kg and 0.187% per day respectively. Gobra zebu females were about 50 and 99% mature at about 12 and 87.6 months respectively.

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Analysis De Los Prametros De Las Curvas De Crecimiento De Hembras Cebu Gobra

Resumen Se llevó a cabo un análisis de los parámetros de las curvas de crecimiento de hembras Cebú Gobra, utilizando los datos de peso colectados desde 1968 hasta 1980 en la Estación de Investigación de Dahra, Senegal. El mes de nacimiento tuvo poco o ningun efecto, en el tamaño adulto y tasa de maduración. Las hembras nacidas entre la mitad de la estación lluviosa y la mitad de la estación seca, alcanzaron pesos maduros menores que aquellas nacidas entre la mitad de la estación seca y la mitad de la estación lluviosa. El año de nacimiento afectó tanto al peso en edad madura, como a la tasa de maduración (P<0·01 y P<0·001 respectivamente). El reproductor utilizado tuvo efecto (P<0·05) sobre la tasa de maduración y ninguno sobre el tamaño en la edad adulta. Las correlaciones genéticas entre la tasa de maduración y peso corporal al nacer, al destete, 12 y 18 meses, fueron 0·45±0·51, –0·21±0·52, –0·61±0·57 y –0·76±0·51 respectivamente. Se esperaria, que la selección para tasa de maduración en hembras Gobra, disminuiría los pesos al destete y post-destete. Les medias de mínimos cuadrados de tamaño a edad madura y tasa de maduración, fueron 398·83±45·81 kg y 0·187% por día respectivamente. Las hembras Gobra Cebú, fueron cerca del 50 y 99% maduras cerca de los 12 y 87·6 meses respectivamente.

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Analyse Des Parametres Des Courbes De Croissance Des Vaches Zebu Gobra

Résumé On a entrepris une analyse des paramètres des courbes de croissance en utilisant les données pondéralés enregistrées de 1968 à 1980 à la station de recherches de Dahra, au Sénégal. Le mois de naissance n'a que peu ou pas d'effet sur la taille à l'état adulte et le taux de croissance. Les vaches nées du milieu de la saison des pluies au milieu de la saison sèche ont plus de chance d'avoir des poids adultes moins élevés que celles nées du milieu de la saison sèche au milieu de la saison des pluies. L'année de naissance affecte à la fois le poids adulte et le taux de croissance. Le mâle a un effet sur le taux de croissance et aucun sur la taille adulte. Les corrélations génétiques entre le taux de croissance et les poids à la naissance, au sevrage, à 12 et 18 mois sont respectivement de 0.45±0.51, –0.21±0.52, –0.61±0.57 et –0.76±0.51. On doit s'attendre à ce que la sélection effectuée sur le taux de croissance des femelles Gobra diminue les poids au sevrage et après sevrage. Les moyennes des moindres carrés des poids adultes et des taux de croissance sont respectivement de 398.83±45.81 kg et de 0.187 p. 100 par jour. Les vaches zébu Gobra sont adultes à 50 p. 100 et 99 p. 100 respectivement à environ 12 et 87.6 mois.

     

Depletion of residues of benzoylprop-ethyl in soil

The depletion of residues of benzolyprop-ethyl ( I ) and its hydrolysis product N-benzoyl-N-(3,4-dichlorophenyl)-DL -alanine ( II ) in soils is reported from various trials following applications of I to soil and crops at up to 3 kg ha^?1. Quite rapid hydrolysis of I to II occurred in most soils and depletion of II followed. The total residue of I and II in the soil often initially increased, probably because of transfer of chemical from the crop to the soil, but the time for 50% disappearance of the total residue ( I+II ) was normally between 4 and 16 weeks. When four sites were treated for three successive years, carry-over of residues was negligible in three sites and showed no progressive increase in the fourth.     

A new freeze-dried living virus vaccine against sheep-pox

A sheep-pox virus strain has been adapted and multiplied in primary lamb kidney cell cultures. The main characteristics of the strain have been verified in vitro after clones were isolated, and the results confirmed its identity. The safety and the potency of the strain have been investigated in sheep.

The inoculation of the strain to sheep was followed by a post-vaccinal reaction materialised by a nodule at the site of inoculation and an increase of temperature by about 1°C. No reactions adversely affecting pregnancy have been noted. Immunisation was demonstrated by an increase in the level of neutralising serous antibodies and protection against the pathogenic virus. The immunity tended to decrease during the second year after primovaccination and a yearly booster vaccination appeared to be necessary. Primovaccination of lambs over 2 months of age produced a better immunity, especially when the lambs were born from vaccinated ewes.

This strain forms the active principle of a freeze-dried vaccine containing no adjuvant of the immunity.     

Cucullanus oceaniensis sp. n. (Nematoda: Cucullanidae) from Pacific eels (Anguilla spp.)

A new species of parasitic nematode, Cucullanus oceaniensis sp. n., is described from the intestine of the giant mottled eel Anguilla marmorata (type host) from Futuna Island (Wallis and Futuna Islands, Polynesia) and from A. marmorata and Anguilla sp. (cf. obscura) from Fiji Islands (Melanesia, South Pacific). The main distinguishing characteristics are the length of spicules (668-1,020 microm), situation of deirids (slightly anterior to the oesophago-intestinal junction) and the excretory pore (some distance posterior to the end of oesophagus), and the arrangement of caudal papillae in the male. It is the third known species of Cucullanus from Oceania and the first one reported from freshwater eels in the region of South Pacific. Cucullanus faliexae Morand et Rigby, 1998 is considered a junior synonym of Cucullanus australiensis Baylis, 1927.     

Acral mutilation and analgesia in 13 French spaniels

Acral mutilation and analgesia (AMA) is reported in 13 French spaniels in Canada. This newly recognized disorder shares striking similarities in clinical features and biopsy findings to the other acral mutilation syndromes or hereditary sensory neuropathies reported in German short-haired pointer dogs, English pointer dogs and English springer spaniels. Clinical signs are first noted between 3.5 and 12 months of age. Affected dogs lick, bite and severely self-mutilate their distal extremities resulting in ulcers with secondary bacterial infection. Auto-amputation of claws, digits and footpads occurs in severe cases. Single or multiple feet can be affected. Affected dogs walked on their severely mutilated feet without evidence of pain, lameness, or ataxia. The majority of the dogs were euthanized within days to months of diagnosis.     

Effect of breed and gender on bovine liver cytochrome P450 3A (CYP3A) expression and inter-species comparison with other domestic ruminants

The cytochrome P450 (P450) superfamily represents a group of relevant enzymes in the field of drug metabolism and several exogenous or constitutional factors contribute to regulate its expression. Cattle represent an important source of animal-derived food-products and studies concerning the P450 expression are needed for the extrapolation of pharmacotoxicological data from one species to another and for the evaluation of the consumer's risk associated with the consumption of harmful residues found in foodstuffs. In the present study, possible breed-, gender- and species-differences in P4503A (the P450 subfamily more expressed in the human liver) expression were studied in vitro in Piedmontese (PDM) and Limousin (LIM) meat cattle breeds of both sexes and in domestic Ruminants (cattle, sheep and goats). Cytochrome P450 and P4503A contents as well as CYP3A-dependent drug metabolising enzymes (DME) were measured in liver microsomes. Significant lower levels of P450 (P < 0.001) and P4503A (P < 0.05) contents were observed in PDM vs. LIM of both sexes; the P4503A-dependent DME activities were significantly (P values ranging from 0.05 up to 0.001) higher in PDM cattle, particularly in males. A gender-effect in DME activities was noticed (P < 0.05) only in PDM male cattle. With regards to the species, the expression of both P4503A apoprotein and some of the related DME activities were more pronounced in sheep (P < 0.01 vs. cattle) and in goats (P < 0.05 vs. sheep; P < 0.01 vs. cattle) than in cattle. The significant differences in P4503A expression observed in LIM and PDM cattle are consistent with previously published data on strain- and breed-differences pointed out in rats and men. As far as a possible sex-effect is concerned, no clear-cut evidence is likely to be drawn. Finally, P4503A expression was more relevant in small ruminants.     

Epizootic Rabbit Enteropathy: experimental transmission and clinical characterization

In late 1996 in France, a severe digestive disease appeared in fattening domestic rabbits. Named the Epizootic Rabbit Enteropathy (ERE), this digestive syndrome has become the main cause of mortality in rabbit farming. The diagnosis in field conditions is difficult because co-infection with other common rabbit pathogens is frequent. By using specific pathogenic free (SPF) rabbits and starting from a field sample of intestinal contents of diseased animals, a virulent material (inoculum) was obtained free of almost all known pathogens but reproduced the symptoms and lesions of ERE. Four hundred and seven SPF rabbits were used in five trials to describe the disease. ERE is characterized by a high contagiousness, 30 to 40% mortality in a few days and about 100% morbidity whatever the dose of the inoculum used. Clinical signs and lesions evolved acutely with the first sign (rambling noise) appearing one day after inoculation and the disease peaking 4 to 6 days later. Growth was strongly lowered from the second day to the end of the second week. Rambling noise and distended abdomen were frequent, mucus excretion and cecal impaction were frequent but not constant. ERE at necropsy was characterized by the absence of any inflammatory or congestive lesions on the gut or on other organs but with the typical presence of a stomach and/or duodenum dilated by liquid and gas and by the absence of specific histological lesions. The etiological agent has not been identified yet, but we demonstrate that the intestinal content was infectious as early as the second day. This work constitutes the experimental basis for studies on this emerging disease within the framework of etiological research led in different European laboratories working with the infectious material.