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1.
2.
The aerobic bacterial flora of the genital tract was characterized in 15 stud dogs in an 18-month study. The dogs represented 4 breeds and were from 3 kennels. Bacterial samples from the prepuce and semen were collected every month, except in connection with matings, when they were collected weekly (464 samples). The dogs that were included all mated at least once during the study. The mean pregnancy rate, litter size, and pup mortality for the bitches with which they had mated were all within normal limits. The most frequent bacteria isolated from the prepuce and semen were Pasteurella multocida, beta-hemolytic streptococci, and Escherichia coli. There was a tendency for breeds to differ in frequency of the most common bacterial species. Bacterial culture yielded no aerobic growth in 14.2% of the preputial samples and 69.8% of the semen samples. Bacteria were transferred between dog and bitch at mating. In this study of healthy breeding dogs, neither the fertility of the dog nor that of the bitch was affected by the bacteria transferred. 相似文献
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4.
Endocrine effects of heat stress in boars 总被引:1,自引:0,他引:1
K. Larsson S. Einarsson K. Lundstrm J. Hakkarainen 《Acta veterinaria Scandinavica》1983,24(3):305-314
The purpose of this study was to describe the temporal changes in peripheral plasma levels of testosterone and Cortisol in boars during and after heat stress. A total of 8 boars were utilized, 4 of them were exposed to 35°C, for 100 h in a climatic room, and 4 served as controls and were kept at 20 °C for 100 h in the climatic room.Blood samples were obtained via permanent vein catheters 3 times daily from 5 days before heat stress until 20 days after termination of heat stress. Testestorone levels were determined by radioimmunoassay and Cortisol by a competitive protein binding technique.For both hormones the pre-exposure levels were similar in both groups of boars. The control boars had significantly higher testosterone levels, while being in the climatic room, than during any other period. The experimental boars had slightly increased testosterone levels during the first day of heat stress and thereafter continuously decreased levels. In the control boars the testosterone levels returned to pre-exposure levels immediately after removal from the climatic room, whereas in the experimental boars the testosterone levels were dramatically increased during the first 5 days after exposure. The differences in Cortisol levels, between the 2 groups of boars were restricted to the period spent in the climatic room. During this period the experimental boars had significantly higher Cortisol levels.Key words: boars, heat stress, testosterone, cortisol 相似文献
5.
Development, survival, reproduction rate, and population growth parameters of the mealy plum aphidHyalopterus pruni (Geoffroy) (Hom.: Aphididae) were evaluated on four different apricot cultivars (Tyrinte, Sakıt, Colomer, and Bebeco) under
field conditions in the Van region of Turkey. Experiments were carried out on exterior leaves of trees, 1.5–2 m above the
ground. Plexiglas clip-cells (25×6 mm) with the upper side covered by muslin were used in the experiments. The mealy plum
aphid performed better on Tyrinte than on the other cultivars tested. The fastest development time (first instar to adult;
9.4 days), highest daily reproduction rate (2.6 offspring/aphid/day), and highest total fecundity (48.1 offspring/aphid) were
obtained on Tyrinte. The intrinsic rate of increase — a good indicator of the growth potential of a population — of individuals
fed on Tyrinte was significantly greater than that of individuals fed on cvs. Colomer and Bebeco. While mean generation times
(T
o
) of populations on different cultivars were close to each other, the net reproductive rate was the highest (29.45 offspring/aphid/generation)
on Tyrinte and the population doubling time on Tyrinte was 18.7%, 25.2% and 26.3% faster than those of individuals on other
cultivars tested. The results obtained in this study indicated that Tyrinte appeared to be the most susceptible to the mealy
plum aphid among the cultivars tested.
http://www.phytoparasitica.org. posting Nov. 23, 2004. 相似文献
6.
An outbreak ofDichelia cedricola (Diakonoff) (Lep.: Tortricidae), the cedar shoot moth (CSM), began in spring 1998 and lasted 3 years. This was the first
monitored outbreak of the CSM in Isparta, Turkey. Tree crowns recovered to near normal condition by the middle of each growing
season (in early June) during the outbreak. Tree volume and volume element increments were examined throughout the outbreak
cycle from 1954 to 2001. In the past, CSM activity in stands of Lebanon cedar (Cedrus libani A. Rich.) was assessed through radial increment analyses. Cedar tree ring chronologies were analyzed for evidence of the
CSM. Tree-ring chronologies from nonhost cedar (nondefoliated sample trees) were used to estimate potential growth in the
host cedar (defoliated sample trees) during current and past outbreaks; all trees selected were the same subspecies and varieties.
Regional outbreaks of the CSM were identified by synchronous and sustained growth periods of the trees. In 2001, increment
cores were collected from 17 host and 16 nonhost dominant or codominant trees and annual radial growth indices from 1954–2001
were calculated for each of two host and two nonhost sample plots. Growth functions were defined as the cumulative sum of
radial, height, and volume increment, and were graphically compared between CSM host cedar and nonhost cedar trees. Tree ring
evidence suggests that a large-scale outbreak occurred in 1955 (from 1955 to 1966) and a small outbreak occurred in 1985 (1985–1990)
and in 1998 (1998-continued) in the study area. The average diameter growth reductions around 1955, 1985 and 1998 were 40%,
46% and 7% of potential, respectively. It was concluded that a narrow latewood band is significant indicator of defoliation
by the CSM and the outbreaks appear to be associated with dry winter and spring weather prior to the autumn and winter in
which wood feeding occurred.
http://www.phytoparasitica.org posting Nov. 24, 2004. 相似文献
7.
Weed control, an important practice in agroecosystems to protect crop production, is usually achieved with herbicides. However,
these pesticides are expensive, pose potential risks to the environment, may affect some beneficial organisms indirectly,
and decrease overall arthropod biodiversity, including pests and their natural enemies, by removing weeds that might act as
hosts or shelters for many organisms. The activity density response of important surface-dwelling arthropod predators (ground
beetles [Coleoptera: Carabidae], ants [Hymenoptera: Formicidae] and spiders [Arachnida: Araneae]) to herbicides (trifluralin
and paraquat), and to two alternative weed management practices (rye straw mulch and mechanical treatment to maintain weeds
below threshold levels, in comparison with an untreated check), was assessed using pitfall traps. The mulch treatment had
the greatest effect on activity density, reducing the number of predators trapped significantly (P<0.05). Herbicide use resulted in significant (P<0.05) reductions in the activity density of ground beetles. Most predators were trapped in the check plots — which had the
highest weed biomass, followed in turn by numbers trapped in the threshold weed control treatment, the full herbicide application
and the mulch treatment plots.
http://www.phytoparasitica.org posting July 10, 2002. 相似文献
8.
G Zamaratskaia J Babol A Madej EJ Squires K Lundström 《Reproduction in domestic animals》2004,39(3):168-172
This study describes the age-related variation in boar taint compounds, skatole and androstenone, and testosterone, oestradiol-17 beta (E17 beta), oestrone sulphate (ES), dehydroepiandrosterone sulphate (DHEAS), triiodothyronine (T(3)) and insulin-like growth factor-1 (IGF-1) in six boars. Three pairs of littermates of crossbred entire male pigs (from three Yorkshire x Duroc dams and one Hampshire sire) were included. Blood samples were taken at the age of 9-15 weeks and thereafter at weekly intervals from the age of 20-32 weeks. Plasma concentrations of skatole, androstenone, testosterone, E17 beta, ES, DHEAS, T(3) and IGF-1 were measured. We found that skatole levels in boars increased at the age around puberty after an increase in the levels of testicular steroids. Levels of skatole were not associated with the levels of sex steroids, T(3) and IGF-1. However, the increased level of testicular steroids is probably the underlying factor needed for high skatole levels to occur although the specific mechanism leading to increased skatole levels remains unknown. 相似文献
9.
D Gavier-Widén M N?remark S Benestad M Simmons L Renstr?m B Bratberg M Elvander C H?rd af Segerstad 《Journal of veterinary diagnostic investigation》2004,16(6):562-567
Within the framework of the active surveillance for transmissible spongiform encephalopathies in sheep in Sweden, 4 cases of the atypical form of scrapie, Nor98, were identified during 2003. Nor98 is a recently recognized and poorly understood variant of scrapie, first described in Norway. The cases were positive by the rapid test (enzyme-linked immunosorbent assay). Immunohistochemical staining showed diffuse thin-granular staining of the cerebellar cortex. Western immunoblotting analysis of specimens of brain stem and cerebellum showed a light band of approximately 12 kDa. Typical scrapie was ruled out based on the confirmatory testing. The affected ewes were from 4 different flocks. They were between 7 and 9 years old. Two were of the ARQ/ARQ genotype, 1 ARR/ARQ, and 1 ARR/AHQ. Two ewes had shown ataxia, and the other 2 had no clinical signs. Whole-flock slaughter was applied, and testing of the flock mates did not reveal additional cases. Nor98 differs from typical scrapie in its epidemiology, frequency of genotypes of sheep affected, clinical signs, microscopic lesions, distribution of scrapie prion protein in the brain, and characteristics of the immunostaining and immunoblotting profiles. 相似文献
10.
Feray Alkan S. Bilge-Dagalp Z. Karapınar M. O. Timurkan N. Coskun I. Burgu 《Tropical animal health and production》2018,50(2):353-363
A follow-up study from 2005 to 2010 was carried out in two herds where eradication programme for the bovine herpes virus-1 (BoHV-1) infection depends on the vaccination with inactivated glycoprotein E-deleted vaccine that was started in 2001 following the vaccination with inactivated conventional vaccine between 1999 and 2001. For serological screening, a total of 12,976 sera sampled over several sampling times approximately 6 months of interval during 5 years (2005–2010) were tested for glycoprotein E (gE)- and glycoprotein B-specific antibodies using ELISA. According to the serological evidence, the long-term persistence of BoHV-1 antibodies, success of marker vaccine, first vaccination time of the calves in herds regularly vaccinated, etc. were discussed in this paper. In conclusion, the vaccination programme using gE (?) marker vaccines, with making efforts to prevent the other factors about transmission of infection, was suggested for the eradication of BoHV-1 infection in Turkey as many EU countries. This is the first report on the BoHV-1 eradication programme in some dairy cattle in Turkey. 相似文献