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191.
Eight experiments were conducted with 451 ewes to test effects of ergonovine, prostaglandin F2 alpha (PGF2 alpha) and phenylephrine on sperm transport and fertility. In most experiments, ewes were mated at estrus and necropsied 2 or 3 h later. Sperm were flushed from the oviducts, uterus and anterior, middle and posterior thirds of the cervix and counted. Various doses of PGF2 alpha or phenylephrine given im at mating caused no significant increase in sperm numbers in any segment of the tract 2 h later. Three different dose levels of ergonovine were given im to ewes in natural estrus 1 h after mating and ewes were necropsied 3 h after mating. Doses of .2 and 1.0 mg were ineffective, but .5 mg increased sperm numbers about 10-fold in the oviducts and uterus. When given im at the time of artificial insemination, .6 mg of ergonovine increased the fertilization rate at 3 d from 5/25 in control ewes to 12/25 (P less than .05). In three experiments with ewes in PGF2 alpha-induced estrus, .6 mg of ergonovine increased sperm numbers in the cervix and uterus at 3 h after mating and in the uterus and oviducts at 23 h, near ovulation. Other ewes were artificially inseminated in the external cervical os and one-half of the ewes were given .6 mg of ergonovine im; ewes not returning to estrus were laparotomized at 22 to 26 d and embryos removed. After insemination during natural estrus with .2 ml of semen, pregnancy rates were 14/25 for control ewes and 15/25 for ergonovine-treated ewes; after insemination during natural estrus with .1 ml of semen, 6/35 and 18/35 (P less than .005); after insemination during PGF2 alpha-induced estrus with .2 ml of semen, 7/60 and 12/60. Fertilization and pregnancy rates combined were 32/145 (22%) for all control ewes and 57/145 (39%) for ergonovine-treated ewes (P less than .005). 相似文献
192.
A necrotizing skeletal myopathy of rear limbs was diagnosed in 17 flocks of commercial turkeys. The mean mortality attributed to the myopathy was 2.29% (range = 0.13-9.7%) over a mean period of 9.6 days (range = 6-14 days). The mean age of the birds at the time of onset was 7.4 weeks (range = 4-10.5 weeks). Clinically, birds experienced an episode of watery droppings and high-pitched crying, followed by rear-limb paresis or paralysis. Creatine kinase and aspartate aminotransferase were markedly elevated in birds with the myopathy. Grossly, a few birds had pale streaking in the muscles of the thighs and legs. Histologically, acute and subacute degeneration was present in myofibers of the legs, abdomen, thighs, back, and tail. The subacute lesion was characterized by marked sarcolemmal cell proliferation. Feed analyses ruled out selenium deficiency and the presence of mycotoxins as etiologies. Monensin was present in approved usage or only slightly elevated levels. A known potentiating antibiotic was being used concurrently with monensin in only one flock. 相似文献
193.
A profile off the penicillin concentration in bovine conjunctival sac fluid (CF) was determined after a single subconjunctival injection of procaine penicillin (6 x 10(5) iu in 2ml). When the injection was made through the skin of the upper eye lid, the duration of therapeutic concentration was significantly greater (P<0.01) than when the injection had been given by the perconjunctival route: approximately 68 hours or 40 hours respectively. These findings support the clinical use of subconjunctivally administered procaine penicillin in the treatment of infectious bovine keratoconjunctivitis. A single application of an equivalent dose of either procaine penicillin or benethamine penicillin, applied topically in a simple occulentum base, produced a therapeutic duration in CF of 37 +/- 4 hr and 56 +/- 4.5 hr respectively. 相似文献
194.
195.
Growing evidence suggests wildlife stewardship behaviors might be affected by emotional dispositions toward particular species. To test this hypothesis, we studied wildlife management choices made by backyard citizen scientists (N = 448) involved in two North American bird nest monitoring projects. Our exploratory study characterized nest monitors’ efforts to manage invasive house sparrows, which compete with native songbirds for nesting sites, and examined the relative influence of cognitive and affective factors on management orientations. Results revealed that nearly all respondents engaged in some form of house sparrow management, and most respondents favored a combination of lethal and non-lethal management approaches. Core affect, emotional dispositions, and experiential variables were the primary drivers of citizen scientists’ management decisions, with anger toward house sparrows and firsthand contact with house sparrow damage as the strongest positive correlates of lethal management orientations. Findings highlight the potentially powerful influence of affect and emotions on wildlife stewardship actions. 相似文献
196.
197.
Retrospective evaluation of the use of glucagon infusion as adjunctive therapy for hypoglycemia in dogs: 9 cases (2005–2014) 下载免费PDF全文
198.
Context
Increasing demands on land for agriculture have resulted in large-scale clearance and fragmentation of forests globally. In fragmented landscapes, species that tolerate or exploit the matrix will persist, while those that do not, frequently decline. Knowledge of matrix use is therefore critical to predicting extinction proneness of species in modified landscapes and defining the value of land for conservation management.Objectives
In a fragmented landscape consisting of seven remnant patches surrounded by agricultural land and a large Eucalyptus forest, we explored (i) population connectivity of common ringtail possums, Pseudocheirus peregrinus, to determine the permeability of the agricultural matrix, and (ii) genetic consequences of forest fragmentation.Methods
238 common ringtail possums were screened at 14 microsatellite markers and analysed using a range of genetic techniques.Results
We observed significant genetic differentiation among all patches and limited dispersal through the agricultural matrix, even between neighbouring patches. Consequences of this were a six- to ten-fold increase in genetic dissimilarity over an equivalent geographic distance across patches compared with sites in the continuous forest and a significant reduction in genetic diversity, particularly in patches that were geographically more isolated from their neighbours.Conclusions
We conclude that the agricultural matrix has a number of characteristics that make it unsuitable for facilitating movement of possums through this landscape, and recommend several management strategies to mitigate the impacts of fragmentation on this and other arboreal species for their conservation.199.
200.
A. S. Bowman J. M. Nolting J. D. Workman M. Cooper A. E. Fisher B. Marsh T. Forshey 《Zoonoses and public health》2016,63(1):34-39
Agricultural fairs create an unconventional animal–human interface that has been associated with swine‐to‐human transmission of influenza A virus (IAV) in recent years. Early detection of IAV‐infected pigs at agricultural fairs would allow veterinarians to better protect swine and human health during these swine exhibitions. This study assessed the use of swine body temperature measurement, recorded by infrared and rectal thermometers, as a practical method to detect IAV‐infected swine at agricultural fairs. In our first objective, infrared thermometers were used to record the body surface temperature of 1,092 pigs at the time of IAV nasal swab collection at the end of the exhibition period of 55 agricultural fairs. IAV was recovered from 212 (19.4%) pigs, and the difference in mean infrared body temperature measurement of IAV‐positive and IAV‐negative pigs was 0.83°C. In a second objective, snout wipes were collected from 1,948 pigs immediately prior to the unloading of the animals at a single large swine exhibition. Concurrent to the snout wipe collection, owners took the rectal temperatures of his/her pigs. In this case, 47 (2.4%) pigs tested positive for IAV before they entered the swine barn. The mean rectal temperatures differed by only 0.19°C between IAV‐positive and IAV‐negative pigs. The low prevalence of IAV among the pigs upon entry to the fair in the second objective provides evidence that limiting intraspecies spread of IAV during the fairs will likely have significant impacts on the zoonotic transmission. However, in both objectives, the high degree of similarity in the body temperature measurements between the IAV‐positive and IAV‐negative pigs made it impossible to set a diagnostically meaningful cut point to differentiate IAV status of the individual animals. Unfortunately, body temperature measurement cannot be used to accurately screen exhibition swine for IAV. 相似文献