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51.
Factors Affecting the First Service Conception Rate of Cows in Smallholder Dairy Farms in Bangladesh
MAR Siddiqui ZC Das J Bhattacharjee MM Rahman MM Islam MA Haque JJ Parrish M Shamsuddin 《Reproduction in domestic animals》2013,48(3):500-505
The successful outcome of an insemination is a combination of both male and female fertility‐linked factors. We investigated the first service conception rate of cows at artificial insemination (AI) in the smallholder dairy farms in Bangladesh. Frozen straws were prepared from ejaculates of Bos indicus (n = 7) and Bos indicus × Bos taurus (n = 7) AI bulls. Fertility was determined from 6101 first services in cows that were performed by 18 technicians in four regions between April 2004 and March 2005. Pregnancy was diagnosed by rectal palpation between 60 and 90 days post‐insemination. The Asian version of Artificial Insemination Database Application (AIDA ASIA) was used for bulls‐, cows‐ and AI‐related data recording, and later retrieved for analysis. The mean ± SD number of inseminations performed from individual bulls and their conception rates were 436.0 ± 21.6 and 50.7 ± 1.9%, respectively. Logistic regression demonstrated body condition scores (BCS), heat detection signs, months of AI and their interactions had greatest effects (odds ratios: 1.24–16.65, p < 0.04–0.001) on first service conception rate in cows. Fertility differed (p < 0.02–0.001) between the regions, previous calving months, months of AI, BCS, parity and heat detection signs of cows. Inseminations based on mounting activity (n = 2352), genital discharge (n = 3263) and restlessness and/or other signs (n = 486) yielded a conception rate of 53.6%, 48.8% and 50.1%, respectively (p < 0.05). Conception rate between technicians ranged between 43.4% and 58.6% (p < 0.05). The days interval from calving to first service (overall mean ± SD = 153.4 ± 80.6) had relationship (p < 0.001) with BCS, months of previous calving and parity of the cows. Fertility at AI in smallholder farms can be improved by training farmers on nutrition and reproductive management of the cows. 相似文献
52.
Liposomes are artificial membrane vesicles that can be used to test and model the functions and interactions of various biological membranes, or as a carrier system to deliver biologically active substances into the cells, or to incorporate lipids into the plasma membrane of target cells to modify membrane structure–function relationships. Sperm plasma membrane undergoes lipid modification during maturation in epididymis and during capacitation in the female reproductive tract to facilitate fertilization. Natural variation in the amounts and composition of lipids in the sperm plasma membrane may also contribute to the species‐specific sperm sensitivities to handling and storage conditions. Boar sperm are notoriously susceptible to membrane damage and are resistant to compositional alteration by artificial liposomes. This study used flow cytometry to demonstrate stable incorporation of nanoliposomes prepared from a complex mixture of various phospholipids (phosphatidylcholine : phosphatidylethanolamine : sphingomyelin : phosphatidylserine : phosphatidylinositol) with high fusion efficiency. Over 90% of sperm rapidly took up fluorescently labelled liposomes and retained the lipids for at least 60 min, in a significant time‐ and concentration‐dependent manner. This unique fusion efficacy could be used to alter sperm plasma membrane composition and hence membrane‐based functional responses. 相似文献
53.
H. De Haan 《Euphytica》1954,3(3):188-194
Summary The varietal assortment of Dutch round blue pea varieties has changed considerably. At the beginning of this century their cultivation was based entirely on the varieties bred by Dr R. J. Mansholt at Westpolder (Gr.). Since 1937 the Unica pea produced by P. J. Hijlkema, Mensingeweer (Gr.), has gained ground. Mansholt's G.E.K. and Unica were dominant for many years, and were also used abroad.A remarkable change in the varietal assortment of the round blue peas occurred since the appearance of varieties less susceptible to the Fusarium solani foot disease. Particularly the Rondo C.B. pea of the Plant Breeding Station C.B. (Dir.: Ir C. Koopman) at Hoofddorp has become widely grown (Fig. 2).In addition, it was this same station that succeeded in breeding a variety entirely resistant to fusarium wilt.It is clear that, in the course of the past few years, new varieties have been bred by the breeders. The new varieties excelled the established ones in one or more respects.Some varieties were widely distributed, others were discarded by the breeders after a couple of years, or (since 1924, the year when the first List of Varieties appeared) written off the List.Widely cultivated varieties had to retire in their turn when better ones came on the market.Even at present time Dutch plant breeders are working hard to improve the yield, quality and reliability of peas. 相似文献
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55.
Noboru SASAKI Yoshinori IKENAKA Yumiko INOUE Takahiro ICHISE Noriyuki NAGATA Mayumi ISHIZUKA Syouta MM NAKAYAMA Kensuke NAKAMURA Mitsuyoshi TAKIGUCHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(4):648
Measurement of urinary metanephrines in spot samples is used for the diagnosis of canine pheochromocytoma (PC). We describe a simple analytical method based on liquid chromatography tandem mass spectrometry (LC-MS/MS) for measuring free metanephrine (MN) and normetanephrine (NMN) in spot urine samples. Using the developed method, we evaluated the stability of urinary free-MN and free-NMN at various storing conditions. In addition, we assessed the feasibility of urinary free-MN and -NMN measurement for diagnosing PC. Urine samples were mixed with stable isotope internal standards and thereafter purified by ultrafiltration. The purified samples were analyzed by LC-MS/MS in the multiple reaction monitoring mode after separation on a multimode octa decyl silyl column. The coefficient of variation of free-MN and -NMN measurement was 7.6% and 5.5%, respectively. The linearity range was 0.5–10 µg/l for both analytes. Degradation was less than 10% for both analytes under any of the storage conditions. The median free-NMN ratio to creatinine of 9 PC dogs (595, range 144–47,961) was significantly higher (P<0.05) than that of 13 dogs with hypercortisolism (125, range 52–224) or 15 healthy dogs (85, range 50–117). The developed method is simple and may not require acidification of spot urine. The results of this preliminary retrospective study suggest that the measurement of urinary free metanephrines is a promising tool for diagnosing canine PC. 相似文献
56.
H. De Haan 《Euphytica》1958,7(2):197-221
In this article a survey is given of old and new books on general plant breeding. They cover a period of some 60 years. A total of 220 titles has been mentioned. The survey has been subdivided in 17 groups according to language; a comment on most groups is given.An approximately equal number of books has been published in English and in German. It can be stated that about half of the total have been published in other languages. Most books in German are written by German authors; the majority of books in English are of American origin.Textbooks supply the needs of instruction on plant breeding and are also popular among plant breeders. 相似文献
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59.
H. de Haan 《Euphytica》1958,7(1):31-37
Potato breeding proper in the Netherlands started in 1888 at the initiative of Geert Veenhuizen at Sappemeer. He was very successful in breeding new potato varieties and stimulated Dutch farmers to tackle potato breeding.On November 18, 1957, just 100 years from the day that Veenhuizen was born, a memorial meeting was held at Sappemeer. Veenhuizen's significance was illustrated and a portrait presented to the Agricultural University.Reproductions of the portrait and a memoir in higher, secondary and primary agricultural schools will keep alive Veenhuizen's significance for agriculture in the Netherlands. 相似文献
60.
H. de Haan 《Euphytica》1961,10(3):357-362
The developing research on plant breeding induced a need for periodicals. Various were founded and in countries which did not start a plant breeding journal the research workers continue to make use of general and genetic periodicals or of foreign plant breeding journals. Much is still being published in annual reports or reports of congresses with a limited distribution.It may be expected that more and more the research on plant breeding will be published in specific journals and also in a language which is generally understood. In this way efficiency of publication will be furthered.The author gives a survey of the 16 periodicals in the field of research on plant breeding and one abstracting journal. 相似文献