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11.
Evaluation of 845 cattle from Florida and Georgia for onchocerciasis indicated a significantly higher prevalence of infection with Onchocerca gutturosa and a significantly lower prevalence of infection with Onchocerca lienalis in the southern portion of Florida (subtropical region) than in the northern portion of Florida or in Georgia (temperature region). In all regions, prevalence of infection with O gutturosa was significantly higher than infection with O lienalis. In the temperate region, bulls were infected more often with O lienalis than were cows. Other sex-related differences in infection with either filariid was not found. Prevalence of infection with O lienalis was similar between age groups in all regions. Rates of infection with O gutturosa differed between age groups within and between subtropical and temperate regions. Examination of cervical and umbilical skin specimens for microfilariae detected an additional 6.6% of infected animals that had not been found by examination for adult worms. However, microfilariae were not found in 21.4% of animals that were positive for adult worms.  相似文献   
12.
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.  相似文献   

13.
The aim of the present study was to clarify the relation between salsolinol (SAL)‐induced prolactin (PRL) release and photoperiod in goats. A single intravenous (i.v.) injection of SAL was given to adult female goats under short (8 h light, 16 h dark) or long (16 h light, 8 h dark) photoperiod conditions at two different ambient temperatures (20°C or 5°C), and the PRL‐releasing response to SAL was compared to that of thyrotropin‐releasing hormone (TRH) or a dopamine (DA) receptor antagonist, sulpiride. SAL, as well as TRH or sulpiride, stimulated the release of PRL promptly after each injection in both 8‐ and 16‐h daily photoperiods at 20°C (P < 0.05). The area under the response curve (AUC) of PRL for the 60‐min period after injections of saline (controls), SAL, TRH and sulpiride in the 16‐h daily photoperiod group was greater than each corresponding value in the 8‐h daily photoperiod group (P < 0.05). There were no significant differences in the AUC of PRL among the values produced after the injection of SAL, TRH and sulpiride in 16‐h daily photoperiod group; however, the values produced after the injection of TRH were smallest among the three in the 8‐h daily photoperiod group (P < 0.05). The PRL‐releasing responses to SAL, TRH and sulpiride under a short and long photoperiod condition at 5°C resembled those at 20°C. These results show that a long photoperiod highly enhances the PRL‐releasing response to SAL as well as TRH or sulpiride in either medium or low ambient temperature in goats.  相似文献   
14.
We investigated conservation value (CV) related to the quality of spider communities in different non-wooded habitat patches - ranging from arable land to natural grasslands. The study was conducted in two ecologically distinct regions of Hungary: the Hungarian Great Plain and the Buda Hills. We used seven variables to indicate CV which together formed a multi-criteria space of spider community characteristics. These variables were either related to species characters obtained from an extensive background database: abundance and frequency based rarity, specialist status, association to natural habitats; or were calculated for the community at the given patch: species richness, functional diversity and species evenness. Using the variables in an ordination analysis we could establish a gradient of the patches in the multi-criteria space of the spider community characteristics. Position of patches along the first axis of the ordination was taken as the multi-criteria measure of CV. CVs established this way were strongly and positively correlated with an independent botanical CV assessment. We also sought a simpler measure of spider CV by: (a) calculating only one variable out of the seven and using it as a surrogate for the multi-criteria CV measurement; by (b) calculating this variable only for a short time period or (c) for only one spider family. Average abundance based rarity value of the species proved to be the best surrogate of the multi-criteria CV measure for both regions, and it also performed very well when sample size was restricted to two sampling occasions per patch or to a single family. This adds further evidence to, what has been found in other studies, that species rarity is a sensitive and reliable measure of the ecological and conservational status of communities.  相似文献   
15.
Abstract

The insecticidal efficacy of microwave irradiation against the at 12, 24, 48 and 72?h following exposure to microwave irradiations (100, 300?W) and the progeny production was assessed 45?days later. Linearly increasing irradiation power range (100, 200 and 300?W) was set up for determining mortality tendency. An increase of insect mortality caused by higher irradiation period and times elapsed after treatment has become evident commencing from 12?h after the treatment, which has significantly decreased at later elapsed time after treatment. The irradiation periods inducing the highest mortality at the examined powers were at 10?min and at 100?W power (72?h: 64.93%) and at 4.5?min. and at 300?W power (12?h: 87.01). In addition, a complete suppression of progeny production was achieved by 4.5?min treatment at 300?W power. Lognormal-type mortality process was caused by the linearly increased irradiation range. The properly chosen microwave irradiation can be used for management of Sitophilus granarius larval and adult developmental stages. This treatment could provide an effective and friendly environmental treatment technique in Integrated Pest Management (IPM) program.  相似文献   
16.
Atrophic rhinitis (AR) is a widespread and economically important disease of swine caused by Bordetella bronchiseptica and Pasteurella multocida. It can be controlled by vaccination. This study investigates the effect of altering the composition (adjuvants and/or addition of formalin-inactivated P. multocida toxin, fPMT) of conventional vaccines on the serological profile and on protection against AR in swine. A significantly higher B. bronchiseptica specific antibody titre was detected for vaccines with novel immunostimulants, the best being Montanide IMS 1313 (1:630 compared to 1:274 obtained with alum). The highest B. bronchiseptica antibody titre was demonstrated for a combination of B. bronchiseptica--fPMT, while PMT antibody titre was highest for monovalent fPMT (both adjuvanted with IMS 1313). The AR-specific antibodies were transmitted from dams to their offspring in similar titres and with the same hierarchy of effectiveness. After a B. bronchiseptica--P. multocida bacterial challenge, piglets from dams vaccinated with fPMT combined with B. bronchiseptica or B. bronchiseptica--P. multocida bacterins showed the lowest nasal lesions scores (4.5 and 3.2, respectively, out of a possible maximum score of 18). These combinations, both of which were adjuvanted with IMS 1313, gave the best protection against experimentally induced AR. Our results show that the adjuvant and the antigen composition of the vaccine strongly affect seroconversion, and that the AR-specific antibody titre does not necessarily correlate with the degree of protection.  相似文献   
17.
Ten guinea pigs with an ovarian cyst had clinical signs of anorexia, alopecia, or depression. Ultrasonographic features of the 2- to 3-cm diameter fluid-filled cysts included compartmentalization and connection to the ovary. In two animals, a unilateral cyst was present, and in two others, the cysts were bilateral. Diagnosis of the disease by plain radiography is difficult because of the similar opacity of ovarian cysts, abdominal neoplasms, and trichobezoars.  相似文献   
18.
19.
The quantity of available wheat gluten exceeds the current food use markets. Thermoforming is an alternative technical means for transforming wheat gluten. Thermoforming was applied here to wheat gluten under chemically reductive conditions to form pliable, translucent sheets. A wide variety of conditions, i.e., temperature, reducing agents, plasticizers and additives were tested to obtain a range of elastic properties in the thermoformed sheets. These properties were compared to those of commercially available polymers, such as polypropylene. Elasticity of the gluten formulations were indexed by Young's modulus and were in the range measured for commercial products when tested in the 30-70% relative humidity range. Removal of the gliadin subfraction of gluten yielded polymers with higher Young's modulus since this component acts as a polymer-chain terminator. At relative humidity less than 30% all whole gluten-based sheets were brittle, while above 70% they were highly elastic.  相似文献   
20.
BACKGROUND: The deployment of synthetic attractants for the manipulation of lacewing populations as aphid predators is currently used in integrated pest management. This study investigates a synthetic bait comprising floral compounds previously found to attract the Chrysoperla carnea complex, and, for the first time, the aphid sex pheromone components (1R,4aS,7S,7aR)‐nepetalactol and (4aS,7S,7aR)‐nepetalactone, in field experiments in Hungary, for their ability to manipulate lacewing populations. RESULTS: The synthetic floral bait attracted both sexes of the Chrysoperla carnea complex, and Chrysopa formosa Brauer showed minimal attraction. The aphid sex pheromone compounds alone attracted males of C. formosa and C. pallens (Rambur). When the two baits were combined, Chrysopa catches were similar to those with aphid sex pheromone baits alone, but carnea complex catches decreased significantly (by 85–88%). CONCLUSION: As the floral bait alone attracted both sexes of the carnea complex, it showed potential to manipulate the location of larval density via altering the site of oviposition. Aphid sex pheromone compounds alone attracted predatory males of Chrysopa spp. and can potentially be used to enhance biological control of aphids. For the carnea complex, however, a combination of both baits is not advantageous because of the decrease in adults attracted. Assumptions of intraguild avoidance underlying this phenomenon are discussed. Copyright © 2010 Society of Chemical Industry  相似文献   
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