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101.
Bayemi P. H. Leinyuy I. Nsongka V. M. Webb E. C. Ebangi A. L. 《Tropical animal health and production》2010,42(8):1779-1783
A study was carried out to evaluate the viability of extended cattle semen, without freezing, under different storage conditions.
The semen was collected from Holstein Friesian bulls using artificial vaginas. The semen was extended and stored in a 3-by-4
factorial design (storage system × ice change). The storage media were ice boxes, buckets, and refrigerator. The ice in these
media was either replaced daily, on the first and third day, first day only, or no ice at all after the semen collection.
Results showed an overwhelming evidence of the effect of storage medium and ice change on sperm viability (P < 0.0001). Individual motility before processing was highest in the refrigerator with averages of 44.5%, 39.5% in ice boxes,
and 10% in buckets during the 8-day experiment. There was no significant difference (P > 0.05) in progressive motility after processing in the refrigerator (34%) and in ice boxes (33%) but significantly higher
(P < 0.01) to the 10% obtained in buckets. It was shown that spermatozoa in the ice box retained 45% individual motility up
to the sixth day after semen was collected on the condition that the ice was changed on the third day. Progressive motility
after processing in the ice box was 40% up to the sixth day with the ice changed on the third day while the spermatozoa were
well preserved up to the fourth day in the same medium if the ice put on the first day was not changed. This study shows that,
if farmers plan to inseminate cows within the first day after semen collection, they can use buckets with ice for the transportation
of the extended semen ampoules from the artificial insemination center. Otherwise, the semen needs to be kept in ice boxes
and the ice changed on the third day after collection and this semen could be used within a week. 相似文献
102.
Webb TL Burnett RC Avery AC Olver CS 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2010,39(4):424-432
Background: Characterization of anemia in horses presents a challenge, as they do not release reticulocytes into peripheral blood. Transferrin receptor (TfR) expression is highest on erythroid cells in people and rats, and measurement of a soluble serum form (sTfR) is used to quantify erythropoiesis in these species. We hypothesized that equine TfR (eTfR) expression is similar in quantity and distribution to that in these other species and thus has potential for characterization of the regenerative response in anemic horses. Objective: This study was conducted to clone and sequence the eTfR gene and measure expression levels using quantitative real‐time PCR and immunohistochemical (IHC) staining. Methods: Total RNA from equine bone marrow was used to produce cDNA. The eTfR gene was amplified using pooled gene‐specific primers, and PCR products were sequenced. Rapid amplification of cDNA ends was used to obtain the first 22 nucleotides of the coding sequence. Quantitative PCR was performed using eTfR gene‐specific primers, and IHC staining was used to localize TfR protein expression. Results: The deduced amino acid (aa) sequence (767 aa) of the eTfR was 75–83% identical with sequences of the receptor in several other mammals. As in people and rats, eTfR mRNA expression was highest in the bone marrow, and distribution in other tissues was also similar. Conclusion: The eTfR gene is similar to that of other mammals in structure and expression levels. We hypothesize that it is also similar in function and that, following development of an immunoassay, determining sTfR concentrations will be useful for identifying the regenerative response in anemic horses. 相似文献
103.
104.
Jay L. Haddock Ray D. Jackson W. O. Harrington R. L. Olson W. J. Weston Mary L. Belote W. J. Hooker A. P. Benson R. W. Hougas S. J. Poloquin R. W. Ross G. V. C. Houghland Wm. G. Hoyman D. R. Isleib N. R. Thompson T. Miyamoto E. J. Wheeler S. T. Dexter Hugh J. Murphy Michael Goven Alvah L. Perry G. H. Rieman D. B. Robinson R. H. Larson J. G. Walker R. L. Sawyer Lawrence A. Schaal Clark H. Livingston Ora Smith W. L. Smith Vilhelm Umaerus L. M. Ware W. A. Johnson R. E. Webb E. S. Schultz Donald A. Young L. C. Young 《American Journal of Potato Research》1958,35(3):441-449
105.
106.
Ajmer S. Bhagsari Raymon E. Webb Sharad C. Phatak Casimir A. Jaworski 《American Journal of Potato Research》1988,65(7):393-406
Selected potato (Solanum tuberosum L.) genotypes were grown in the field from May to September during 1984 and 1985, to study their growth and gas exchange responses in a warm climate. The parameters measured were leaf area index (LAI), canopy photosynthesis on ground area basis (CPn-Ga), stomatal conductance, dry matter partitioning and yield. The LAI ranged from 1.40 for Dakchip to 6.60 for Pungo during August 1984. The LAI also differed significantly among the potato genotypes for the three samplings during 1985. Atlantic, Chipbelle and DTO-33 showed no decline in their LAI up to 73 days after planting (DAP), indicating a better heat-stress tolerance response than the other genotypes. During both years, CPn-Ga differed significantly among the genotypes and Pungo had higher CPn-Ga than all the other genotypes. Mean CPn-Ga rates were 1.72 and 4.34 g CO2 m?2hr?1 during 1984 and 1985, respectively. Mean adaxial and abaxial stomatal conductances were 0.86 and 1.46 cm sec?1, during 1984, and stomatal conductances were similar for both years. Stomatal conductance did not appear to limit gas exchange in potato leaves. Dry matter partitioning to tubers ranged from 8.9% for Pungo to 55.5% for Atlantic 67 DAP during 1984. At final harvest, July 19, 1985, dry matter partitioning to tubers varied from 47.5% for Pungo to 69.9% for Chipbelle. The tuber yield ranged from 9.6 to 27.8 MT/ha. This study indicated that Atlantic and La Chipper have potential for growing in a warm climate. 相似文献
107.
Johannes Vernooij Florine de Munck Evelien van Nieuwenhuizen Edward Webb Herman Jonker Peter Vos Dietmar Holm 《Reproduction in domestic animals》2020,55(11):1592-1598
Pelvis size plays an important role to prevent dystocia in cattle caused by the foeto-maternal disproportion in commonly primiparous females. The reproducibility and repeatability are two important aspects for the reliability of the measurements to use in the selection of cattle for culling. Pelvic measures were taken with a Rice pelvimeter from 224 young cattle (180 females and 44 males) of four beef breeds in South Africa. One experienced and two inexperienced observers each measured pelvic height and width twice. The proportion measurements with a maximum difference of 0.5 cm within animal compared with the first measurement by the experienced observer are around 80% and by the inexperienced observers around 50% for pelvic height and around 60% for pelvic width. Breed and sex do not affect the reliability of pelvimetry by an experienced observer. Under- and overestimation of pelvis size were observed in inexperienced observers, which seems to be unrelated to breed and sex. 相似文献
108.
Upland cotton (Gossypium hirsutum) requires adequate nitrogen (N) for optimum yields. Foliar applications of urea to supplement soil applied N have been tried for many years across the Cotton Belt, but responses have been highly variable. No published information is available regarding response by irrigated cotton to foliar applied N in subtropical South Texas. This study investigated the response of cotton to foliar applied urea and triazone N over a three-year period near Weslaco, Texas. In all years, foliar applied urea tended to increase seed cotton yield when soil applied N was limiting. In the absence of soil applied N, the increase due to foliar urea was significant in two of the three years (28.7 and 15.7% increases). Foliar applied triazone N was ineffective at increasing seed cotton yields. 相似文献
109.
ABSTRACT Nitrogen (N) deficiency limits cotton yields, while too much N causes excessive vegetative growth hurting yields, wastes expensive inputs, and causes environmental pollution. Diagnostic indicators are needed to assess cotton N status so that yields can be optimized as efficiently as possible. This study evaluated selected tools for predicting cotton responses to N fertilizer application. Petiole nitrate (NO3)-N (PNN) concentration was found to correlate with cotton N status and a good indicator of potential for response to N application. Critical PNN concentrations for irrigated cotton in subtropical South Texas at first bloom, and 10, 20 and 30 d later were determined to be 15.0, 9.0, 4.5, and 2.0 g kg? 1, respectively. These critical PNN levels are higher than in more humid areas of the traditional southern US Cotton Belt, probably due to the effects of the subtropical climate. Cotton plants in this area tend to be less vegetative, possibly due to shorter growing season day lengths, and therefore need to be “pushed” slightly harder with greater N fertilization. Leaf total N concentrations were found to be less responsive to changes in applied N than were PNN levels. Although leaf N tended to be more stable over time, there was no consistent pattern between years. Leaf N values of 35 g kg? 1 or less appear to represent a deficiency at any time, and optimum levels may be slightly higher. Nodes above white flower showed very small responses to N fertilization and the differences occurred late in the bloom period. Chlorophyll meter readings showed a good relationship with N fertilizer application within a given sampling date, but much greater variability occurred between dates and due to other factors. The most effective indicator of cotton N status was found to be PNN, and to a lesser extent leaf N, but none of other parameters could be recommended for purposes of making inferences as to N status of cotton. 相似文献
110.