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1.
Baris Guner Gulsum Selcuk Sevket Guclu Sultan Sengul Ismail Altun Serdal Dikmen Ahmet Gumen 《Reproduction in domestic animals》2021,56(9):1254-1260
The objective of the study was to compare the fertility after using sex-sorted or conventional semen either with oestrus detection (EST) or timed artificial insemination (TAI) in Holstein heifers. Holstein heifers were randomly assigned to one of the following treatments in a 2 × 2 factorial design. Heifers in the EST group were inseminated with sex-sorted (n = 114) or conventional semen (n = 100) after spontaneous or induced oestrus. Heifers in the TAI, subjected to the 5-day Cosynch+Progesterone protocol (GnRH+P4 insertion-5d-PGF2α+P4 removal-1d-PGF2α-2d-GnRH+TAI), were inseminated with sex-sorted (n = 113) or conventional semen (n = 88). Statistical analyses were performed using PROC GLIMMIX procedure of SAS 9.4 (SAS Institute Inc., Cary, NC). Overall P/AI was 60.7% for EST and 54.2% for TAI regardless of types of semen and 68.1% for conventional and 48.9% for sex-sorted semen regardless of insemination strategies. Fertility of heifers inseminated with either sex-sorted (53.5%; 44.2%) or conventional (69.0%; 67.0%) semen did not differ between EST and TAI respectively. Besides, the interaction between the semen type and the insemination strategy was not significant for P/AI. The embryonic loss was significantly greater with sex-sorted semen (17.1%) compared to conventional semen (1.6%). There was no sire effect with sex-sorted semen on P/AI (52.6% vs. 46.2%) and embryonic loss (16.4% vs. 18.0%). As expected, sex-sorted semen resulted in more female calves (89.8% vs. 51.6%) than conventional semen. Thus, sex-sorted semen can be used with 5-day Cosynch+Progesterone protocol to eliminate the inadequate oestrus detection and to increase female calves born in dairy heifers. 相似文献
2.
1. The conchae within the nasal cavity of poultry are important for water and energy conservation, but have not been experimentally evaluated. The aim of the present study was to determine the accuracy of volume and volume fraction estimates of the conchae, nasal septum and nasal cavity.
2. The nasal cavities of 7 adult goose heads were scanned using computed tomography (CT), with images sampled randomly at a 1/5 sampling fraction. Physical sections were obtained from the same samples, using an electric saw that had an adjustable section range, and provided 14 to 15 sections with a thickness of 2.5 mm. The section surface areas of the nasal cavity, nasal septum and conchae were estimated using the Cavalieri principle. Results obtained using the CT and physical section images were compared. Volumes and volume fractions obtained from the physical sections were accepted as the gold standard and differences in the CT images were determined.
3. Multiplication of the data obtained on the CT images with the deviation percentage of the physical sections produced normalised values. No differences were observed between the gold standard data and the CT images. While it was possible to normalise the obtained data using the gold standard values, the raw data could also be used for comparative studies because the deviations from normal would be similar for all groups.
4. Our study showed that the nasal structures could be estimated in vivo using CT images. 相似文献
3.
Combined use of hyperspectral VNIR reflectance spectroscopy and kriging to predict soil variables spatially 总被引：1，自引：0，他引：1
Hyperspectral visible near infrared reflectance spectroscopy (VNIRRS) and geostatistical methods are considered for precision
soil mapping. This study evaluated whether VNIR or geostatistics, or their combined use, could provide efficient approaches
for assessing the soil spatially and associated reductions in sample size using soil samples from a 32 ha area (800 × 400 m)
in northern Turkey. Soil variables considered were CaCO3, organic matter, clay, sand and silt contents, pH, electrical conductivity, cation exchange capacity (CEC) and exchangeable
cations (Ca, Mg, Na and K). Cross-validation was used to compare the two approaches using all grid data (n = 512), systematic selections of 13, 25 and 50% of the data and random selections of 13 and 25% for calibration; the remaining
data were used for validation. Partial least squares regression (PLSR) analysis was used for calibrating soil properties from
first derivative VNIR reflectance spectra (VNIRRS), whereas ordinary-, co- and regression-kriging were used for spatial prediction.
The VNIRRS-PLSR method provided better prediction results than ordinary kriging for soil organic matter, clay and sand contents,
(R
2 values of 0.56–0.73, 0.79–0.85, 0.65–0.79, respectively) and smaller root mean squared errors of prediction (values of 2.7–4.1,
37.4–43, 46.9–61, respectively). The EC, pH, Na, K and silt content were predicted poorly by both approaches because either
the variables showed little variation or the data were not spatially correlated. Overall, the prediction accuracy of VNIRRS-PLSR
was not affected by sample size as much as it was for ordinary kriging. Cokriging (COK) and regression kriging (RK) were applied
to a combination of values predicted by VNIR reflectance spectroscopy and measured in the laboratory to improve the accuracy
of prediction of the soil properties. The results showed that both COK and RK with VNIRRS estimates improved the predictions
of soil variables compared to VNIRRS and OK. The combined use of VNIRRS and multivariate geostatistics results in better spatial
prediction of soil properties and enables a reduction in sampling and laboratory analyses. 相似文献
4.
BACKGROUND: The aim of this study was to investigate the prevalence of hepatitis B virus (HBV) genotypes in Isparta, Southwest of Turkey, as well as the clinical features and transmission route for patients with HBV infections. METHODS: Patients (n = 135) with HBV infection were included in the study. Epidemiological and clinical data were obtained. HBV genotypes were determined with a preS2 epitope ELISA kit. RESULTS: Although the HBV transmission route remained unidentified in 51.1% of the patients, blood contact was determined as the most common probable transmission route (38.5%). One hundred twenty-four (91.8%) of 135 samples, could be genotyped. One hundred fifteen (85.1%) were genotyped as type D/E, six (4.4%) were genotyped as type A, two (1.4%) were genotyped as type C, and one (0.7%) were genotyped as type F. CONCLUSION: Genotype D/E is determined as the predominant HBV genotype circulating in Isparta, Southwest of Turkey. No relationship between genotypes and disease severity and transmission route has been detected. 相似文献
5.
Spray solutions containing 0.3% Ca which were prepared from four different calcium sources were foliar-sprayed on greenhouse-grown
tomato plants, infected with theTomato mosaic virus Tobamovirus (ToMV) or not. ToMV-infected and uninfected control groups were sprayed with distilled water. Growth and macronutrient
(N, P, K, Ca and Mg) composition of tomato plants as well as virus concentration and its relative infectivity were investigated
in treated and untreated plants. The Ca sprays were applied three times: on the same day as inoculation, and 15 and 30 days
after inoculation. Virus concentration in tomato plants generally decreased with foliar-sprayed Ca. Virus concentration (DAS-ELISA
absorbance) was reduced by foliar-sprayed Ca, but plants remained infected. At the same time, tissue Ca concentrations increased
significantly with foliar-applied Ca, with the exception of CaNO3·4H2O+0.05M Na-EDTA. ToMV reduced the fresh and dry weights and Ca concentrations of tomato plants, but significantly raised P concentration
in the tissue. Neither virus inoculation nor foliar Ca applications affected N and Mg concentrations in tomato plants. The
foliar-applied Ca from all the sources gave K concentrations similar to those of control plants.
http://www.phytoparasitica.org posting Jan. 26, 2007. 相似文献
6.
Journal of Pest Science - The larvae of Curculio elephas (Coleoptera: Curculionidae) and Polyphylla fullo (Coleoptera: Scarabaeidae) are major agricultural pests of chestnut and roots of cultivated... 相似文献
7.
Comparisons were made between yield measurements with an impact based yield sensor and an electronic scale in adjacent harvest strips and on the same grain stream within a combine. Yield measurements in adjacent strip comparisons were more prone to errors as the segment lengths decreased. Grain yield difference between the yield sensor and electronic scale ranged from 5 to 14%, 4 to 13%, 3 to 12%, and 2 to 11% for 15, 30, 60, and 300 m long segments. The yield differences between neighboring segments might have been caused by yield variability to a degree; however, a consistent decrease in yield differences with increasing segment lengths implied that better accuracies could be obtained in longer management areas. The combine responses to grain yield changes and the effect of varying ground speed on accuracy were also evaluated by creating artificial yield patterns in harvest strips. Grain diffusion within the combine was more obvious when abrupt yield changes were introduced at known locations. Grain mixing and redistribution inside the combine may dictate the selection of segment sizes in the site-specific decision making process. Constant ground speed provided more stable grain flow values than varying ground speed. The average error in yield estimate was 3.4% and 5.2% at constant ground speed and varying speed, respectively. Careful calibration and constant combine speed were important to achieve better accuracy with the grain yield monitor. 相似文献
8.
9.
Fruit Yield and Quality,and Irrigation Water Use Efficiency of Summer Squash Drip-Irrigated with Different Irrigation Quantities in a Semi-Arid Agricultural Area 
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下载免费PDF全文 Fruit yield, yield components, fruit mineral content, total phenolic content, antioxidant activity and irrigation water use efficiency (IWUE) of summer squash responses to different irrigation quantities were evaluated with a field study. Irrigations were done when the total evaporated water from a Class A pan was about 30 mm. Different irrigation quantities were adjusted using three different plant-pan coefficients (Kcp, 100% (Kcp1), 85% (Kcp2) and 70% (Kcp3)). Results indicated that lower irrigation quantities provided statistically lower yield and yield components. The highest seasonal fruit yield (80.0 t ha−1) was determined in the Kcp1 treatment, which applied the highest volume of irrigation water (452.9 mm). The highest early fruit yield, average fruit weight and fruit diameter, length and number per plant were also determined in the Kcp1 treatment, with values of 7.25 t ha−1, 264.1 g, 5.49 cm, 19.95 cm and 10.92, respectively. Although the IWUE value was the highest in the Kcp1 treatment (176.6 kg ha−1 mm−1), it was statistically similar to the value for Kcp3 treatment (157.1 kg ha−1 mm−1). Total phenolic content and antioxidant activity of fruits was higher in the Kcp1 (44.27 μg gallic acid equivalents (GAE) mg−1 fresh sample) and in the Kcp2 (84.75%) treatments, respectively. Major (Na, N, P, K, Ca, Mg and S) and trace (Fe, Cu, Mn, Zn and B) mineral contents of squash fruits were the highest in the Kcp2 treatment, with the exception of P, Ca and Cu. Mineral contents and total phenolic content were significantly affected by irrigation quantities, but antioxidant activity was not affected. It can be concluded that the Kcp1 treatment was the most suitable for achieving higher yield and IWUE. However, the Kcp2 treatment will be the most suitable due to the high fruit quality and relatively high yield in water shortage conditions. 相似文献
10.
Akbas Y Brotherstone S Hill WG 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》1993,110(1-6):105-113
SUMMARY: First lactation production records of pedigree Holstein-Friesian cows in the UK were analysed by an animal model, in order to estimate effects of heterosis and recombination loss between North American Holstein and European Friesian cattle and the influence of these effects on breeding value prediction. Coefficients of heterosis and recombination loss were fitted in the animal model as covariables and unknown parents were assigned to a varying number of genetic groups. The estimates of heterosis effects were 104 kg, 4.3 kg and 2.9 kg for milk, fat and protein yield, respectively, while the corresponding coefficients for recombination loss were -135 kg, -2.6 kg and -3.7 kg respectively. Neither the sire component of variance nor the heritability estimates were appreciably affected by the inclusion of heterosis and recombination loss in the model. Including both these effects in the breeding value estimation increased the predicted sire proof for fat plus protein of a typical F1 Holstein × Friesian sire by 3 kg. ZUSAMMENFASSUNG: Tiermodellsch?tzungen nicht-additiv genetischer Parameter bei Milchrindern und ihre Auswirkung auf Heritabilit?tssch?tzung und Zuchtwertvoraussage Laktationsleistungen von Herdbuch Holstein-Friesen Kühen im UK wurden mittels eines Tiermodells analysiert zur Sch?tzung der Wirkungen von Heterosis und Rekombinationsverlust zwischen nordamerikanischen Holstein und europ?ischen Schwarzbunten und Einflu? dieser Wirkungen auf Zuchtwahlvorhersagen. Koeffizienten für Heterosis und für Rekombinationsverlust wurden im Tiermodell als Co-Variable berücksichtigt und unbekannte Eltern einer unterschiedlichen Zahl genetischer Gruppen zugeordnet. Sch?tzungen der Heterosiswirkungen waren 104 kg, 4,3 kg und 2,1 kg für Milch-, Fett- Proteinmengen, w?hrend die diesbezüglichen Koeffizienten für Rekombinationsverlust -135, -2,6 und -3,7 kg waren. Weder die Vatervarianzkomponente noch Heritabilit?tswerte wurden durch Berücksichtigung von Heterosis und Rekombinationsverluste im Modell tangiert. Berücksichtigung beider Wirkungen in der Zuchtwertsch?tzung erh?hte den gesch?tzten Vaterzuchtwert für Fett + Protein eines typischen F1 Holstein-Friesen-Stieres um 3kg. 相似文献