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41.
It is useful to determine the gestational age in sheep to provide essential information for effective flock management practices. The aims of this study were to evaluate the efficacy and practical aspects for using two ultrasound techniques, transabdominal and transrectal, in determining the gestational age in Württemberg ewes. Monitoring of embryo and fetus developmental stages during the ewes’ gestation was carried out with real time ultrasound using a transabdominal convex probe, frequency 3.5 MHz, and a transrectal linear probe, frequency 7.5 MHz. The size of the embryonic vesicle during the period from the 23rd to the 38th day of gestation can be used as a confirmational indicator of gestational age when the transrectal probe is used. The occipital nasal diameter correlated with the gestational age with both transabdominal (P < 0.05) and transrectal probes (P < 0.01) from the 46th to the 63rd day of gestation. The biparietal diameter of the fetal head measured by transabdominal probe during the period from the 46th to the 63rd day of gestation correlates with gestation age (P < 0.05). The diameter of the fetal eye orbit monitored by transrectal probe from the 46th to the 63rd day of gestation also correlated well with gestational age (P < 0.05).  相似文献   
42.
In a study of the parasitoid complex of the locust leaf miner Phyllonorycter robiniella (Clemens, 1859), 23 species of its parasitoids were recorded at 18 localities in Serbia. The parasitoid species included 2 species of the family Braconidae, 1 of the family Eupelmidae, and 20 of the family Eulophidae. The recorded species of parasitoids are polyphagous; in addition to Ph. robiniella, they also develop on other species of leaf miners as primary; primary and secondary; or primary, secondary, and tertiary parasitoids. Among the recorded species of parasitoids, the most significant were the species Pholetesor bicolor, Pholetesor nanus, Sympiesis sericeicornis, Sympiesis acalle, Minotetrastichus frontalis, Pediobius saulius, and Baryscapus nigroviolaceus. The parasitoids were found to have a strong effect on the abundance of Ph. robiniella because they reduced more than 50% of its larvae and pupae in the majority of study samples.  相似文献   
43.
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