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1.
The known information on hymenopterous parasites of Nitidulidae was consolidated in this article. Species of parasites, nitidulid hosts and, where possible, plant host of the nitidulids are provided along with citations to sources of information. Thirty-three species of hymenopterous parasites are recorded in nine different families. Since nomenclature of several of the parasites has changed, it was updated with the assistance of specialists.  相似文献   
2.
The present study was carried out to investigate the pattern of apoptosis in the healthy antral and atretic follicles of Philippine swamp buffaloes (BU) in comparison with Holstein-Friesian (HF) cows. Paraffin sections of healthy follicles and various stages of atretic follicles were stained using the terminal deoxynucleotidyl transferase (TdT)-mediated biotinylated deoxyuridine triphosphates (dUTP) nick end-labelling (TUNEL) method to detect DNA fragmentation and cleaved caspase-3 antibody to detect cells committed to undergo apoptosis. Five equidistant areas of a follicle were counted for the presence of TUNEL- and caspase-3-positive cells. Healthy follicles of BU and HF contained no TUNEL-positive cells in the granulosa and theca layer but showed some caspase-3 positivity. The granulosa layer of advanced atretic follicles showed a significantly higher frequency of caspase-3 positivity than the healthy and early atretic follicles in both breeds. The frequency of caspase-3-positive cells of BU was significantly higher than HF in the granulosa layer of healthy, early atretic and advanced atretic follicles. In the theca interna layer, BU and HF showed a significantly lower and higher frequency of TUNEL-positive cells in the late atretic follicles compared with advanced atretic follicle, respectively. However, the frequency of caspase-3-positive cells of both BU and HF in the late atretic follicles was significantly higher than the advanced atretic follicles in the theca interna layer. These results indicate that caspase-3 and DNA fragmentation is involved in the buffalo ovarian apoptotic process.  相似文献   
3.
The present study was carried out to describe the proliferative activity of granulosa and theca cells in healthy antral and atretic follicles of Philippine buffaloes (BU) and Holstein-Friesian (HF) cows. Paraffin sections of ovary were immunostained with mouse monoclonal antibody to proliferating cell nuclear antigen (PCNA). Then the follicles were classified into healthy and various stages of atretic follicles. The granulosa layer of healthy follicles had a significantly higher frequency of PCNA-positive cells than the early and advanced atretic follicles in both breeds. In the theca interna, significantly reduced populations of the PCNA-positive cells were found in both breeds as atresia progressed. Moreover, HF had significantly higher PCNA-positive cells in the theca interna of healthy, early atretic and advanced atretic follicles than BU. A reduction of PCNA-positive cells during atresia was also noted in the theca externa in both animals although differences were not significant. The results of the present work suggest that the proliferative activity of granulosa and theca cells decreases in association with follicular atresia in the BU similar to HF. Furthermore, a significantly deficient cell proliferative activity of theca interna was found in BU compared with HF.  相似文献   
4.
AIM: To investigate a possible interaction between lolitrem B and ergovaline by comparing the incidence and severity of ryegrass staggers in sheep grazing ryegrass (Lolium perenne) containing lolitrem B or ryegrass containing both lolitrem B and ergovaline.

METHODS: Ninety lambs, aged approximately 6 months, were grazed on plots of perennial ryegrass infected with either AR98 endophyte (containing lolitrem B), standard endophyte (containing lolitrem B and ergovaline) or no endophyte, for up to 42 days from 2 February 2010. Ten lambs were grazed on three replicate plots per cultivar. Herbage samples were collected for alkaloid analysis and lambs were scored for ryegrass staggers (scores from 0–5) weekly during the study. Any animal which was scored ≥4 was removed from the study.

RESULTS: Concentrations of lolitrem B did not differ between AR98 and standard endophyte-infected pastures during the study period (p=0.26), and ergovaline was present only in standard endophyte pastures. Ryegrass staggers was observed in sheep grazing both the AR98 and standard endophyte plots, with median scores increasing in the third week of the study. Prior to the end of the 42-day grazing period, 22 and 17 animals were removed from the standard endophyte and AR98 plots, respectively, because their staggers scores were ≥4. The cumulative probability of lambs having scores ≥4 did not differ between animals grazing the two pasture types (p=0.41).

CONCLUSIONS AND CLINICAL RELEVANCE: There was no evidence for ergovaline increasing the severity of ryegrass staggers induced by lolitrem B. In situations where the severity of ryegrass staggers appears to be greater than that predicted on the basis of concentrations of lolitrem B, the presence of other tremorgenic alkaloids should be investigated.  相似文献   

5.
The Japanese bayberry whitefly,Parabemisia myricae (Kuwana), was discovered in Israel on citrus and avocado trees in 1978. In order to clarify its mode of overwintering, observations and counts were carried out during the winters of 1979/80, 1982/83 and 1983/84, with the following findings. Larvae and adults were detected on citrus and avocado trees throughout the winter; only females were found. The oviposition rate ofP. myricae in winter was low, and rose steeply in spring. The density of larvae on the lower side of leaves was higher than on the upper side. Substantial numbers of larvae survived the winter on avocado trees. Emergence of adults became intensified at the end of February, reached a peak in early March, and ceased at the end of March or beginning of April.  相似文献   
6.
This study aimed to assess the effects of different cooling curves and centrifugation regimes used in cryopreservation protocols on the post‐thaw viability of Piau‐breed wild boar (Sus scrofa) sperm using in vitro assessment tests. Two centrifugations (800  g for 10 min and 2400  g for 3 min) and two cooling curves (conventional cooling using nitrogen vapour – freezing 1 and automated cooling using a programmed freezing machine – freezing 2) were tested. Therefore, the treatments were divided into M3 – centrifugation at 2400  g for 3 min and freezing 2; M10 – centrifugation at 800  g for 10 min and freezing 2; R3 – centrifugation at 2400  g for 3 min and freezing 1; and R10 – centrifugation at 800  g for 10 min and freezing 1. No significant differences (p > 0.05) between treatments occurred post‐thawing regarding the total sperm motility means recorded. The mean values of the different treatments were not different from each other regarding the supravital staining (SV), hypo‐osmotic test (HO), sperm–egg binding assay or sperm morphology. This study showed that both the cooling curve and the centrifugation regime affected the quality of post‐thaw sperm, and centrifugation for shorter times and cooling curves using automated cooling are the most suitable for minimizing sperm injury.  相似文献   
7.
Milled oat groat pearlings, trichomes, flour, and bran were extracted with methanol and the fractions tested in vitro for antioxidant capacity against low-density lipoprotein (LDL) oxidation and R-phycoerythrin protein oxidation in the oxygen radical absorbance capacity (ORAC) assay. The oxidative reactions were generated by 2,2'-azobis(2-amidinopropane) HCl (AAPH) or Cu(2+) in the LDL assay and by AAPH or Cu(2+) + H(2)O(2) in the ORAC assay and calibrated against a Trolox standard to calculate Trolox equivalents (1 Trolox equivalent = 1 TE = activity of 1 micromol of Trolox). The antioxidant capacity of the oat fractions was generally consistent with a potency rank of pearlings (2.89-8.58 TE/g) > flour (1.00-3.54 TE/g) > trichome (1.74 TE/g) = bran (1.02-1.62 TE/g) in both LDL and ORAC assays regardless of the free radical generator employed. A portion of the oat antioxidant constituents may be heat labile as the greatest activity was found among non-steam-treated pearlings. The contribution of oat tocols from the fractions accounted for <5% of the measured antioxidant capacity. AAPH-initiated oxidation of LDL was inhibited by the oat fractions in a dose-dependent manner, although complete suppression was not achieved with the highest doses tested. In contrast, Cu(2+)-initiated oxidation of LDL stimulated peroxide formation with low oat concentrations but completely inhibited oxidation with higher doses. Thus, oats possess antioxidant capacity most of which is likely derived from polar phenolic compounds in the aleurone.  相似文献   
8.
Australia antigen: detection and transmission in shellfish   总被引:2,自引:0,他引:2  
Australia antigen was found in clams contaminated by drainage of untreated sewage from a coastal hospital. In closed-system aquariums, the antigen was ingested by clams and transmitted to previously uninfected clams. In opensystem aquariums, the titer of Australia antigen decreased with time, suggesting viral concentration rather than replication.  相似文献   
9.
10.
The date stone beetle,Coccotrypes dactyliperda F. (Coleoptera: Scolytidae), is a primary pest of green unripe dates. The adult beetle chews a characteristically round hole in the fruit, which results in the druit dropping 1 or 2 days later. Egglaying and entire development occur within galleries produced by the female in the date stone; males are unable to penetrate the stones. In laboratory cultures and in field-collected date stones, the beetle adult females were predominant (85-93%). Overwintering probably occurs in the adult stage within date stones of fruits which had dropped and were left on the ground. At 28°C the average egg incubation period was 5.9 days, larval duration 12–15 days, and pupal development 4.0 days. Development from egg to adult for females was significantly longer than for males (24.8vs. 22.1 days). Mated females produced males and females, whereas unmated females gave rise to males only. The mean number of progeny per mated female (30.4) was significantly higher than that recorded for unmated females (6.6), but the latter lived significantly longer (73.3vs. 62.9 days).  相似文献   
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