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Development of new semen cryopreservation techniques improving sperm survival and ensuring availability of viable spermatozoa for a prolonged time‐period after AI is promising tools to reduce sensitivity of timing of AI and enhance overall fertility. The SpermVital® technology utilizes immobilization of bull spermatozoa in a solid network of alginate gel prior to freezing, which will provide a gradual release of spermatozoa after AI. The objective of this study was to compare post‐thaw sperm quality and in vitro sperm survival over time of Norwegian Red bull semen processed by the SpermVital® (SV) technology, the first commercialized production line of SpermVital® (C) and by conventional procedure applying Biladyl® extender (B). Post‐thaw sperm motility was not significantly different between SV, C and B semen (p > .05). However, sperm viability and acrosome intactness were higher for SV than C and B semen (p < .05). Small differences in DNA quality were observed (p < .05). Sperm viability after storage in uterus ex vivo was higher for SV than for C semen (p < .05). Furthermore, sperm survival in vitro over time at physiological temperature was significantly higher for SV semen than C semen as well as B semen during the incubation period of 48 hr (p < .05). In conclusion, the SpermVital® technology is improved and is more efficient in conserving post‐thaw sperm quality and results in higher sperm viability over time in vitro for SV than for C and B semen.  相似文献   
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Objective To identify farm factors which were associated with reproductive performance in dairy herds in New South Wales.
Procedure A survey was administered by face to face interview to examine the responses of producers drawn from 757 herds, which used the New South Wales Agriculture Department Dairy Herd Improvement scheme. A case-control approach was used to select a total of 126 herds from the first (top group - cases) and fourth quartiles (low group - controls) for intercalving interval.
Results We found that the estimated interval from calving to first mating was significantly different between groups (P = 0.03) and that the groups significantly differed in both their target for interval to first mating (P = 0.02) and their perceived optimum time for first mating (P = 0.04). Other factors associated with a longer intercalving interval included, use of embryo transfer programs (P = 0.08), younger managers (P = 0.02), fewer breedings per day (P = 0.01), a greater number of people detecting heats (P = 0.07), but less hours spent detecting heats while handling the cows (P = 0.11), and a failure to vaccinate bulls for campylobacteriosis (P = 0.14).
Conclusions Managers of herds with poorer reproductive performance did not intend to mate cattle as soon after calving as managers with better reproductive performance, were not as active in seeking veterinary advice on reproduction, and were attempting to treat reproductive diseases and disorders themselves.  相似文献   
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The present study was aimed at investigating the effect of experimental infection by Trypanosoma vivax in different stages of pregnancy, determining the pathogenesis of reproductive failure, and confirming transplacental transmission. We used 12 pregnant ewes distributed into four experimental groups: G1, was formed by three ewes infected with T. vivax in the first third of pregnancy (30 days); G2 comprised three infected ewes in the final third of pregnancy (100 days); G3 and G4 were composed of three non-infected ewes with the same gestational period, respectively. Each ewe of G1 and G2 was inoculated with 1.25 × 105 tripomastigotes. Clinical examination, determination of parasitemia, serum biochemistry (albumin, total protein, glucose, cholesterol, and urea), packed cell volume (PCV), serum progesterone, and pathological examination were performed. Placenta, amniotic fluid, blood and tissues from the fetuses and stillbirths were submitted to PCR. Two ewes of G1 (Ewe 1 and 3) presented severe infection and died in the 34th and 35th days post-infection (dpi), respectively; but both fetuses were recovered during necropsy. In G2, Ewe 5 aborted two fetuses on the 130th day (30 dpi) of pregnancy; and Ewe 6 aborted one fetus in the 140th day (40 dpi) of gestation. Ewes 2 and 4 delivered two weak lambs that died five days after birth. Factors possibly involved with the reproductive failure included high parasitemia, fever, low PCV, body score, serum glucose, total protein, cholesterol, and progesterone. Hepatitis, pericarditis, and encephalitis were observed in the aborted fetuses. The presence of T. vivax DNA in the placenta, amniotic fluid, blood, and tissues from the fetuses confirms the transplacental transmission of the parasite. Histological lesion in the fetuses and placenta also suggest the involvement of the parasite in the etiopathogenesis of reproductive failure in ewes.  相似文献   
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Veterinary Research Communications - Miraglia D., Ranucci D., Branciari R., Cioffi A., Mammoli R., Cenci Goga B.T. and Avellini P., 2007. Prevalence of Campylobacter jejuni and Campylobacter coli...  相似文献   
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The aim of this study was to evaluate the distribution of frozen–thawed spermatozoa within the uterine lumen and oviducts following intrauterine laparoscopic deposition at two sites. Twelve bitches of unknown reproductive history were randomly distributed into two groups. Semen (3 ml containing 300 × 106 frozen–thawed spermatozoa) was infused at the uterine body (UB group) or at the cranial tip of the left uterine horn. A 22‐G catheter was used to access the uterine lumen. Sperm cell distribution was evaluated after ovariohysterectomy performed 3 h after artificial insemination (AI). There was no difference between groups in mean time to perform AI. Spermatozoa were detected in all uterine segments, including the tip of both horns, but none was detected in the oviduct. The 22‐G catheter facilitated deposition of semen in the uterine lumen, particularly at the UB site. Sperm cell distribution occurred evenly along both horns, independent of the site of semen deposition.  相似文献   
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Dasypyrum villosum (L.) Candargy (DV) is adiploid (2n = 14, VV genomes), allogamous grass of theMediterranean region. It may be hybridized with wheatand is thus a gene resource for wheat improvement. Westudied grain protein concentration andSDS-sedimentation (SED) as indicators of end-usequality. The latter is a good predictor of glutenstrength. A-PAGE and SDS-PAGE were used to identifymonomeric and polymeric seed storage proteins,respectively, to relate proteins of DV to those foundin Chinese Spring (CS), Triticum aestivum L.,wheat. Two full-sib lines of DV had high grain protein(19.3 and 20.3%), but one had very low mean SED (69mm) and one had very high (118 mm) based on onegreenhouse and one field test. CS had very low grainprotein (12.0%) and weak gluten (33 mm). Single-DVchromosome addition and substitution lines and twoDV-wheat recombinant lines all had higher grainprotein than CS (range 13.9 to 16.7%). SED valuesshowed a different pattern. CS=4V and CS=6V hadlow SED, 63 and 44 mm, similar to CS, whereas CS=1Vand full sib DV 200 had very strong gluten, 118 mm, asdid substitution lines CS1V (1A) and CS1V (1B), 125and 131 mm, respectively. One hybrid-derived line withDV-wheat 1V recombinant chromosome had SED of 99 mmand one line with a 6V added chromosome had SED of 64mm. The large positive effects of quality in the wheathaving DV chromosome 1V are believed to be due to DValleles at the Glu-V1 and Gli-V1/Glu-V3loci. DV chromosomes 4V and 6V did not contribute toimproved quality probably due to Gli-V2 and Gli-V3 which, as the orthologous loci in wheat, donot enhance wheat quality. Based on the positiveeffects of alleles on DV chromosome 1V in a breadwheat background, we conclude that D. villosumis a source of allelic diversity that can beconsidered for improving end-use quality in breadwheat.  相似文献   
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