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51.
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The objective of this study was to determine a value of serum progesterone (P4) concentration, assessed using an enzymeimmunoassay (EIA), for the early distinction between pregnant and non‐pregnant ewes and goats. Adult, non‐lactating ewes of Chios (n=53), Berrichon (n=30) and Sfakia (n=45) breeds were synchronized during the breeding season with progestagens and gonadotrophins and mated to fertile rams (Experiment I). Adult, lactating goats of Swiss breeds (Alpine and Saanen, n=104) and indigenous Greek breed (n=45) were synchronized during the transitional season with progestagens, PGF2α and gonadotrophins. Cervical artificial insemination (AI) with fresh semen was applied once, 42–44 h after sponge removal (Experiment II). Jugular blood samples were collected on day 19 after sponge removal (ewes) or on day 21 after AI (goats) and serum P4 concentration was determined by EIA. Progesterone concentrations ≥1.0, ≥1.5, ≥2.5 and ≥4.0 ng/ml were tested as indicative of pregnancy. Pregnancy diagnosis was verified on birth. In the case of sheep, using a discriminatory level of 2.5 ng/ml, overall accuracy of pregnancy diagnosis was 91.4% and predictive value of negative and positive diagnoses were 98.3 and 85.3%, respectively. In the case of goats, predictive value of negative diagnosis was 95.8 and 94.0% and predictive value of positive diagnosis 71.3 and 71.7%, for 1.5 and 2.5 ng/ml, respectively; overall accuracy was 79.2% using either level. The other discriminatory levels tested did not improve these results. A significant positive correlation was observed between P4 concentration and the number of lambs or kids born, and further analysis indicated that this relationship is not a simple linear function. Based on the results of this study, P4 concentrations of 2.5 ng/ml in the case of ewes and 1.5–2.5 ng/ml in the case of goats, determined with EIA, are proposed as discriminatory levels between pregnant and non‐pregnant animals, at an interval of one oestrous cycle after service.  相似文献   
53.
Extract

Between November 1971 and July 1972, the gastro-intestinal tracts of 51 dogs and 47 cats of various age were examined for helminth parasites. The animals examined were unselected and had been submitted for autopsy following death from causes unrelated to parasitism. Most of the animals were pets, but included in the survey were some working dogs. All came either from the city of Palmerston North or its surrounding rural areas.  相似文献   
54.
Splitting of the sun's global oscillation frequencies by large-scale flows can be used to investigate how rotation varies with radius and latitude within the solar interior. The nearly uninterrupted observations by the Global Oscillation Network Group (GONG) yield oscillation power spectra with high duty cycles and high signal-to-noise ratios. Frequency splittings derived from GONG observations confirm that the variation of rotation rate with latitude seen at the surface carries through much of the convection zone, at the base of which is an adjustment layer leading to latitudinally independent rotation at greater depths. A distinctive shear layer just below the surface is discernible at low to mid-latitudes.  相似文献   
55.
Fullerene pipes   总被引:10,自引:0,他引:10  
Single-wall fullerene nanotubes were converted from nearly endless, highly tangled ropes into short, open-ended pipes that behave as individual macromolecules. Raw nanotube material was purified in large batches, and the ropes were cut into 100- to 300-nanometer lengths. The resulting pieces formed a stable colloidal suspension in water with the help of surfactants. These suspensions permit a variety of manipulations, such as sorting by length, derivatization, and tethering to gold surfaces.  相似文献   
56.
Rhodococcus equi infection in goats   总被引:1,自引:0,他引:1  
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57.
Extraskeletal osteoma in a cat   总被引:1,自引:0,他引:1  
This paper describes a case of a benign osseous lesion which arose in the right front leg of an 8-year-old spayed female cat. The growth was situated in the dermal tissue above the olecranon, but not attached to it, and shelled out easily at surgery.
While certain non-neoplastic lesions, such as hamartomas or cases of heterotopic ossification, may appear histologically similar, the present case was considered to be a true tumour on the basis of the clinical, macroscopic and histological findings, and was termed an osteoma. The cat is remaining under observation, but there had been no recurrence 3½ months after surgery.  相似文献   
58.
The Global Oscillation Network Group (GONG) project estimates the frequencies, amplitudes, and linewidths of more than 250,000 acoustic resonances of the sun from data sets lasting 36 days. The frequency resolution of a single data set is 0.321 microhertz. For frequencies averaged over the azimuthal order m, the median formal error is 0.044 microhertz, and the associated median fractional error is 1.6 x 10(-5). For a 3-year data set, the fractional error is expected to be 3 x 10(-6). The GONG m-averaged frequency measurements differ from other helioseismic data sets by 0.03 to 0.08 microhertz. The differences arise from a combination of systematic errors, random errors, and possible changes in solar structure.  相似文献   
59.
60.
The objectives of this study were to investigate the influence of ram age on structural and functional competence of frozen–thawed spermatozoa and to test the hypothesis that increasing number of sperm bound to the zona pellucida in vitro was associated with decreasing in vivo fertility of frozen semen. Rams were allocated into two groups. Each group consisted of five rams aged either 1–2 years (young) or 4–5 years (mature). Three successive ejaculates were collected from each ram using an artificial vagina. Only ejaculates of ≥ 2.5 × 109 sperm/ml and 80% sperm progressive motility were pooled per ram, diluted with Bioxcell® medium and frozen in 0.25 ml straws. The end points of post‐thawing semen evaluation were computer‐assisted cell motility analysis, sperm capacitation (chlortetracycline assay), simultaneous assessment of plasma membrane integrity, mitochondrial membrane potential and condensation status of nucleus, per‐cell analysis of lipid peroxidation using C11‐BODIPY581/591, sperm‐hemizona binding (HZB) ability and sperm fertility after laparoscopic insemination of ewes (n = 114) in the progestagen‐synchronized oestrus. The results showed that mature rams had significantly lower values of sperm hyperactivated motility and peroxidized sperm, higher percentages of live non‐capacitated sperm and sperm cells with intact plasma membrane, functional mitochondria and condensed chromatin, as well as, greater lambing rate and ewe prolificacy. Sperm HZB binding ability was higher (p < 0.05) for young than for mature rams. Significant correlations were found between number of spermatozoa bound to the zona pellucida and semen fertility (r = ?0.63 to ?0.71). In conclusion, mature rams have better semen quality and in vivo fertility than young rams. Cryocapacitation can be involved in decreasing ram semen fertility as evidenced by the high number of spermatozoa bound to the zona pellucida in vitro.  相似文献   
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