Cow effects and estimation of success of first and following inseminations in Dutch dairy cows     

Inchaisri C  Jorritsma R  Vernooij JC  Vos PL  van der Weijden GC  Hogeveen H 《Reproduction in domestic animals》2011,46(6):1043-1049

The objective of this research was to determine the contribution of cow factors to the probability of successful insemination accounting for the serial number of inseminations in analysis. The investigation was performed with 101,297 insemination records in 51,525 lactations of different cows from 1368 herds obtained from the Dutch milk production recording database. Cows that had a first insemination (AI) between 40 and 150 days post-partum with one or more inseminations (≤6 inseminations) were selected. An insemination was defined successful when not followed by another insemination and when the cow calved between 267 and 295 days after insemination, or when the cow was culled between 135 and 295 days after the last insemination. Breed, parity, days in milk, lactation curve characteristics, milk production traits, moment of AI related to peak milk yield time (before or after peak milk yield), the last calf (female, male, twin or stillbirth) and season of insemination were selected as independent parameters for a model with successful rate of insemination as dependent parameter. A multivariable logistic regression model was used within cow and farm as a random effect. The probability of successful insemination was the highest in the first insemination and decreased in the following inseminations. However, the success rate of all inseminations increased in a later stage of lactation. The improvement in the successful inseminations in a later stage of lactation was better in multiparous cows than in first parity cows. Insemination in summer and before peak milk yield time reduced the success of insemination. The success rate was the lowest in 100% Holstein Friesian cows compared with other breeds and was the highest when the last calf was a female calf compared to a male calf, twin or stillbirth. In conclusion, the success of first and following inseminations depended on parity, breed, season of insemination, last calf status, daily milk yield at insemination date, serial insemination number and days in milk at insemination date.  相似文献   

Reliability of pelvimetry is affected by observer experience but not by breed and sex: A cross-sectional study in beef cattle     

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   

The effects of nitrogen supply and stem density on leaf attributes and stem branching in potato (Solanum tuberosum L.)     

J. Vos 《Potato Research》1995,38(3):271-279

Summary The interaction between nitrogen supply and stem density on leaf attributes and branching was studied in two field experiments. Stem densities included 8, 16, 24, 32 and 40 stems m⁻². The low-N treatments received 5 or 10 g m⁻² nitrogen, and the high-N treatments 20 or 25 g m⁻². The sizes of mature individual leaves on the main stem declined with increase in stem density and were larger for greater N supply, with additive effects of nitrogen and stem density. The specific leaf area was not affected by nitrogen supply and increased with stem density (range of values: 210 to 310 cm² g⁻¹). The leaf weight ratio was not affected by the treatments. At 8 and 16 stems m⁻² basal branches contributed substantially to the total leaf area per stem: at 24 stems m⁻² and higher densities the development of basal branches was negligible. Leaf area on apical branches was always smaller for higher plant densities and lower rates of N supply.  相似文献   

Hand-held chlorophyll meter: a promising tool to assess the nitrogen status of potato foliage     

J. Vos  M. Bom 《Potato Research》1993,36(4):301-308

Summary A field experiment with potato (Solanum tuberosum L., cv. Vebeca) was conducted on a sandy soil near Wageningen (52° North) in 1992. The treatments included a zero-nitrogen control and combinations of three amounts of nitrogen, viz. 110, 180 and 250 kg N ha⁻¹, and splitting of the N dose in one (early May), two (early May and June) or three (early May, June, July) applications. The chlorophyll content of the uppermost fully grown leaves was assessed with a SPAD-502 chlorophyll meter (Minolta, Osaka, Japan) throughout the season. The pattern of change with time in SPAd-values differed between treatments. SPAD-502 readings correlated well with laboratory measurements of the chlorophyll content and with the nitrogen concentration in leaves (r ²>0.95). Data on the nitrate concentration in petiole sap (included as a reference) showed that this variable responded much more to split nitrogen applications than the SPAD-value. Future research will need to consider other factors which may affect the chlorophyll content of the foliage.  相似文献   

A case history: Hundred years of potato production in Europe with special reference to the Netherlands     

Jan Vos 《American Journal of Potato Research》1992,69(11):731-751

The production of potatoes has become important in Europe, especially since the 19th century. Since 1850 the yield of ware potatoes increased in The Netherlands from approximately 10 t ha^?1 to the present level of 45 t ha^?1. This was achieved by various improvements in production techniques. Several breakthroughs were accomplished in breeding for host resistance against pathogens. The current use of pesticides (nematicides, herbicides, fungicides, etc.) is high in potato production, at least in The Netherlands, particularly due to the use of fumigants to control nematodes in the starch potato growing areas. The Dutch government adopted objectives with respect to general reductions in the use of pesticides and the leaching of nutrients (nitrate). Adaptations in cultural measures are required to meet these objectives and to arrive at more sustainable systems of production in the future. In this paper special attention is given to past and present problems and possibilities with respect to cyst nematodes, late blight, wart, Colorado potato beetle, nitrogen nutrition, weed control, haulm destruction and sprout suppression.  相似文献   

Interaction of arbuscular mycorrhizal fungi and rhizobia: Effects on flax yield in spoil‐bank clay     

Jana Rydlová  David Püschel  Radka Sudová  Milan Gryndler  Olga Mikanová  Miroslav Vosátka 《植物养料与土壤学杂志》2011,174(1):128-134

This study focused on the application of native strains of arbuscular mycorrhizal fungi (AMF) and Sinorhizobium in effective crop production during reclamation of coal‐mine spoil banks. Two greenhouse experiments were conducted in spoil‐bank clay with a low dose of organic amendment to determine whether the microbial inoculation improves growth and utility qualities of two cultivars of Linum usitatissimum L. (oil and fiber flax). Inoculation with two native AMF isolates (Glomus mosseae, G. intraradices, and their mixture) significantly increased growth and shoot phosphorus (P) concentration of both flax cultivars. Inoculated fiber flax plants produced fivefold more fibers than the uninoculated ones. In oil flax, mycorrhizal inoculation significantly but quantitatively to a minor degree decreased the concentration of nonsaturated fatty acids in the seed oil. A mixture of five native Sinorhizobium sp. strains supported growth and P uptake of oil flax only in the absence of AMF. However, these beneficial effects of the bacteria were significantly lower as compared to AMF. No synergic action of Sinorhizobium strains and AMF was observed, and their interactions were often even antagonistic. Inoculation with AMF significantly decreased population density of Sinorhizobium in the soil. These results suggest that a careful selection of suitable bacterial strains is necessary to provide effective AMF combinations and maximize flax‐growth support.  相似文献   

Spinal cord ependymoma in two young dogs     

H R de Vries-Chalmers Hoynk van Papendrecht  J H Vos  J J van Nes 《The Veterinary quarterly》1988,10(3):205-210

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A feline dental tumor resembling calcifying epithelial odontogenic tumor in man     

J H Vos  S A Goedegebuure  G M Bron-Dietz 《Veterinary pathology》1985,22(5):508-510

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The helminth parasites of various artiodactylids from some South African nature reserves     

J Boomker  I G Horak  V De Vos 《The Onderstepoort journal of veterinary research》1986,53(2):93-102

The helminth species composition and helminth burdens of 4 grey duikers, 12 bushbuck, 2 nyala, 2 giraffe, a steenbok, an oribi, a waterbuck and a tsessebe from the Kruger National Park (KNP); of a steenbok and a greater kudu from the farm Riekerts Laager, Transvaal; of a single blue duiker from the Tsitsikama Forest National Park, and of a blue wildebeest, a red hartebeest, a gemsbok and 2 springbok from the Kalahari Gemsbok National Park (KGNP) were collected, counted and identified. New parasite records are: Agriostomum equidentatum from the gemsbok, Cooperia neitzi from the bushbuck, Cooperia sp. from the gemsbok and the red hartebeest, Cooperia yoshidai from the waterbuck and the tsessebe, Dictyocaulus viviparus from the bushbuck, Haemonchus bedfordi from the waterbuck, Haemonchus contortus from the gemsbok, Haemonchus krugeri from the steenbok from the KNP, Impalaia nudicollis from the gemsbok and the red hartebeest, Impalaia tuberculata from the oribi and the waterbuck, Impalaia spp. from the kudu, Longistrongylus meyeri from the steenbok from Riekerts Laager and the gemsbok, Longistrongylus sabie from the steenbok from the KNP, Longistrongylus schrenki from the tsessebe, Parabronema sp. from the tsessebe and the red hartebeest, Paracooperia serrata from the gemsbok and the steenbok from the KGNP, Pneumostrongylus calcaratus from the bushbuck, Strongyloides sp. from the gemsbok, Trichostrongylus sp. from the gemsbok, the red hartebeest and the steenbok from the KGNP, Trichostrongylus axei from the blue duiker, Trichostrongylus falculatus from the bushbuck and the oribi, Trichostrongylus instabilis from the bushbuck, the steenbok from the KNP and the oribi and Trichostrongylus thomasi from the grey duikers and tsessebe. Host specificity of the parasites was not marked and crossinfestation was common. This was not true for the giraffe, since none of the helminths of these animals were found in the antelope and vice versa.  相似文献   

Desmin and vimentin immunocharacterization of feline muscle tumors.     

J Martín de las Mulas  J H Vos  F N Van Mil 《Veterinary pathology》1992,29(3):260-262

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