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Inhalt: Bei weiblichen Tieren der Rase Weiβes Alpenschaf (WAS) wurden die Einflüsse des Kontaktes mit einem Widder und der Frühjahrsschur (als Temperaturstress) als mögliche Impulse für die Aufhebung des saisonalen Anöstrus untersucht. Die Geschlechts-aktivität der Tiere wurde mittels des wöchentlich gemessenen Progesteron-Plasmaspiegels beurteilt. Ein vasektomierter Widder hielt bei den meisten Schafen der untersuchten
Gruppe die Geschlechtszyklen während des ganzen Jahres aufrecht; kein deutlicher Anostrus konnte beobachtet werden. Die Schur vor oder nach dem Weidebeginn ver-bunden mit einem Wechsel von schlechtem zu gutem Futter und mit einer Klimaänderung induzierte hingegen keine Unterbrechung des Anöstrus .
Contents: Reproductive cycles in White Alpine Sheep: effect of ram and shearing
The ability to interrupt the seasonal anestrus in the presence of a ram (pheromone effect) and after an early shearing (temperature stress) has been investigated on ewes of the race "white alpine sheep". The occurence of estrus was assessed by measuring of plasma progesterone in weekly intervals. No clear anestric period was observed in a group of 10 animals accompanied by a vasectomized ram throughout the whole year. The reproductive cycles of most ewes were regular (18 days). On the other hand, the shearing before or after the beginning of the grazing period that is accompanied by the change of a poor to a rich feed and by a change of climatic conditions, did not systematically influence the anestrus in our experiments . 相似文献
Gruppe die Geschlechtszyklen während des ganzen Jahres aufrecht; kein deutlicher Anostrus konnte beobachtet werden. Die Schur vor oder nach dem Weidebeginn ver-bunden mit einem Wechsel von schlechtem zu gutem Futter und mit einer Klimaänderung induzierte hingegen keine Unterbrechung des Anöstrus .
Contents: Reproductive cycles in White Alpine Sheep: effect of ram and shearing
The ability to interrupt the seasonal anestrus in the presence of a ram (pheromone effect) and after an early shearing (temperature stress) has been investigated on ewes of the race "white alpine sheep". The occurence of estrus was assessed by measuring of plasma progesterone in weekly intervals. No clear anestric period was observed in a group of 10 animals accompanied by a vasectomized ram throughout the whole year. The reproductive cycles of most ewes were regular (18 days). On the other hand, the shearing before or after the beginning of the grazing period that is accompanied by the change of a poor to a rich feed and by a change of climatic conditions, did not systematically influence the anestrus in our experiments . 相似文献
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The aims of this investigation were to determine the prevalence of ovine herpesvirus type 2 (OvHV-2) (the causative agent of malignant catarrhal fever) infection in cattle, the carrier status of sheep and goats, and to define the pattern of acquisition of OvHV-2 in lambs under natural flock conditions in Kashmir, India. None of the buffy coat samples from 21 lambs contained OvHV-2 DNA sequences up to 28 days after birth, only one lamb had sequences of OvHV-2 DNA as early as 29 days after birth, and they were detected in the other 20 lambs when they were between 43 and 94 days of age. Sequences of OvHV-2 DNA were detected in buffy coat samples from 28 (85 per cent) of 33 adult sheep and in 16 (61 per cent) of 26 samples from adult goats by hemi-nested PCR. Seventeen (31 per cent) of 55 cattle with malignant catarrhal fever-like clinical signs had sequences of OvHV-2 DNA in their blood, and nine of the 17 died, all of them during the months of April to November, between November 2002 and March 2004. No clinical cases of sheep-associated malignant catarrhal fever was recorded during the months of December to March. The overall prevalence of OvHV-2 infection in the cattle in the region was estimated to be less than 1 per cent. 相似文献
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Tsai-Yu Lin Chen-Tuo Liao Hari K. Iyer 《Journal of Agricultural, Biological & Environmental Statistics》2008,13(2):221-241
Tolerance intervals are useful in practice to help determine limits for detection monitoring or assessment monitoring of factors that may impact the environment, ecological systems, or other biological processes. This article provides a procedure for construction of one-sided and two-sided tolerance intervals for a normally distributed random variable when the mean and variance of its distribution are estimated using data following an unbalanced one-way random effects model with covariates under heterogeneous error variances. The procedure developed here is based on the concept of a generalized pivotal quantity which has been frequently used to obtain confidence intervals in situations where conventional methods are difficult to apply or fail to provide s satisfactory solutions. For the one-sided case, the generalized pivotal quantity approach yields an exact solution. On the other hand, the method leads to good approximate intervals for the two-sided case. This is confirmed by a detailed simulation study, showing that the method may be recommended for practical use. Two real-data examples are given to illustrate the applicability of the proposed procedures. 相似文献
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Jose Antony Appidi Krishna Reddy Arun Sudhagar Hari Krishna Vungurala Luke A Roy 《Journal of the World Aquaculture Society》2021,52(1):155-170
The suitability of inland saline groundwater as a medium to culture juvenile cobia, Rachycentron canadum, was assessed. In the first experiment, juvenile cobia stocked in raw (unamended) saline groundwater at salinities of 5, 10, and 15 g/L exhibited complete mortality after 108, 176, and 195 hr, respectively. The second experiment evaluated the rearing of juvenile cobia (mean weight ~9.23 ± 0.12 g) in potassium (K+)‐amended saline groundwater (100% K+ fortified) and reconstituted seawater at salinities of 5, 10, and 15 g/L to assess growth and osmoregulation in distinct culture media. Following 60 days of culture, all fish survived the experimental period. Final mean bodyweight of cobia reared in K+‐amended saline groundwater (103.2–115.8 g) and seawater (111.2–113.8 g) of different salinities did not vary significantly (p > .05). No differences (p > .05) were observed in specific growth rate, weight gain (%), and feed conversion ratio between treatment groups. Serum osmolality increased with salinity and was significantly higher (p < .05) for fish in K+‐amended saline groundwater (353–361 mOsmol/Kg) than in reconstituted seawater (319–332 mOsmol/Kg), although differences were not observed between salinities by water type. Cobia stocked in saline groundwater of different salinities were osmoregulating normally, and the higher values observed may be because of variations in ionic composition and other interfering ions in saline groundwater. Trial results suggest that juvenile cobia can achieve optimal growth in K+‐amended saline groundwater of low and intermediate salinities. 相似文献
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There has been growing interest in the use of bioresource waste for natural dyeing and finishing. This paper discusses dye extraction from the novel source fruit shell waste of Sterculia foetida and its application on mulberry silk fabric to confer aesthetic coloration and wellness properties such as ultra-violet (UV) protection and antibacterial properties. Treated fabrics showed a substantial increase in color depth and adequate wash, light, and rubbing fastness properties for dyed silk fabrics with and without mordanting. Pre-and post-mordanting of silk fabrics were carried out using mordants such as alum, harda (myrobalan), and copper sulfate. UV-visible spectrophotometric analysis of fruit shell extract (FSE) at different pHs and FSE with three different mordants at neutral pH was used to understand the phenomena of dye-fiber interaction. The treated fabrics characterised by ATR-FTIR, SEM-EDS, and XRD analysis indicate the nature of dye fiber interaction justifying the multifunctional properties. The treated fabric also showed very good ultraviolet protection property and antibacterial properties both against S. aureus and E. coli bacteria even after ten washes. The results indicate that Sterculia foetida fruit shell extract offers an excellent potential as coloration, antibacterial, and ultraviolet protective agent for mulberry silk fabric. 相似文献
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