Effect of doses and administration routes of 9R vaccine on protection of Japanese quails against experimental infection with Salmonella Gallinarum / Efeito das doses e vias de administração da vacina 9R na proteção de codornas japonesas contra infeccção experimental com Salmonella Gallinarum

Coturniculture has increased significantly in the last decades. There are several pathogens that can affect these birds. Among the diseases, fowl typhoid stands out as a disease with a potentially great impact to the poultry industry. The objective of this the study was to evaluate the effect of doses and administration routes of live 9R vaccine on protection of Japanese quails against experimental infection with Salmonella Gallinarum (SG). Two hundred and fifty birds were used, divided into five groups: G1, oral vaccination with one dose; G2, oral vaccination with 2 doses; G3, subcutaneous vaccination with one dose; G4, subcutaneous vaccination with two doses and G5 not vaccinated. All birds from all five groups were challenged with SG at an age of 45 days. SG was quantified in the periods of one, four, seven and twelve days after the challenge. The presence of clinical signs and macroscopic lesions of the disease were observed. The groups vaccinated by subcutaneous route had a higher egg production and lower mortality rate. Birds receiving a dose of the vaccine by subcutaneous route also showed lower amount of SG in the liver and spleen seven days after the challenge.(AU)

A coturnicultura tem aumentado significativamente nas últimas décadas. Existem vários patógenos que podem afetar essas aves. Entre as doenças, o tifo aviário se destaca como uma doença de grande impacto para a indústria avícola. O objetivo deste estudo foi avaliar o efeito de doses e vias de administração da vacina viva 9R na proteção de codornas japonesas contra infecção experimental por Salmonella Gallinarum (SG). Foram utilizadas duzentos e cinquenta aves, divididas em cinco grupos: G1, vacinação oral com uma dose; G2, vacinação oral com 2 doses; G3, vacinação subcutânea com uma dose; G4, vacinação subcutânea com duas doses e G5 não vacinado. Todas as aves dos cinco grupos foram desafiadas com SG aos 45 dias de idade. A SG foi quantificada nos períodos de um, quatro, sete e doze dias após o desafio. Foi observada a presença de sinais clínicos e lesões macroscópicas da doença. Os grupos vacinados por via subcutânea apresentaram maior produção de ovos e menor taxa de mortalidade. Aves recebendo uma dose da vacina por via subcutânea também apresentaram menor quantidade de SG no fígado e baço sete dias após o desafio.(AU)

Combining regression trees and radial basis function networks.

We describe a method for non-parametric regression which combines regression trees with radial basis function networks. The method is similar to that of Kubat, who was first to suggest such a combination, but has some significant improvements. We demonstrate the features of the new method, compare its performance with other methods on DELVE data sets and apply it to a real world problem involving the classification of soybean plants from digital images.

Effect of alpha-methyldopa on alpha-noradrenergic receptor binding sites in the mouse brain.

alpha-Methyldopa (alpha-MD) was administered intraperitoneally into adult male mice and its effect on alpha 1- and alpha 2-noradrenergic receptor binding sites in the brain was investigated, using [3H]WB-4101 and [3H]clonidine, respectively. A single injection of 50-200 mg/kg alpha-MD abolished the high affinity binding to alpha 2-receptor sites and only the low affinity binding was observed with lower Bmax values. A significant effect of alpha-MD on alpha 1-receptor sites was not detected even after repeated injections (200 mg/kg/day X 3). Pretreatment with fusaric acid or diethyldithiocarbamate (inhibitors of dopamine-beta-hydroxylase) exerted no influence on the actions of alpha-MD on alpha 2-receptor sites, whereas NSD-1055 (an inhibitor of dopa decarboxylase) inhibited the effects of alpha-MD. It is concluded, therefore, that alpha-methyldopamine, a decarboxylated metabolite of alpha-MD, may be responsible for the reducing effect of alpha-MD on alpha 2-receptor sites.

Uptake and metabolism of choline by the embryonic heart of the chick in vitro.

1. The uptake and metabolism of [14C]choline was investigated in isolated hearts from 4- to 14-day-old chick embryos. 2. A high-affinity uptake system of choline was present in hearts from all ages of embryos examined: the Km values were 9-11 muM, while the Vmax values ranged from 5 (14-day ventricles) to 77 (4-day atria) pmol choline/mg protein/min. 3. Hemicholinium-3, metabolic inhibitors, low temperature and low Na+ concentrations reduced the high-affinity uptake process. 4. The accumulated choline was converted mainly into phosphorylcholine in 4-day hearts, while the percentage of conversion into acetylcholine increased in older embryos.

Development of acetylcholine sensitivity of embryonic chick atria in culture.

Atria were isolated from chick embryos of 4--12 days incubation and maintained up to 9 days in culture to examine change in their sensitivity to acetylcholine (ACh). Beating of atria from 4-day embryos was not affected by ACh at the start but was inhibited after a few days of culture. Atria from old embryos which had been sensitive to ACh remained so in culture. Desensitization to ACh was marked in short-term culture of 4-day embryonic atria. Sera and embryo extracts facilitated the appearance of ACh sensitivity. Binding of quinuclidinyl benzilate was observed in ACh-insensitive atria. Cycloheximide, puromycin and actinomycin D prevented the appearance and maintenance of ACh sensitivity in culture, leaving the heartbeat unaffected.