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1.
Toxoplasma gondii is a globally distributed parasitic protozoan that infects humans and other warm‐blooded vertebrates. Felids are the only definitive host for T. gondii, and they excrete oocysts in their faeces. The national prevalence in humans is declining in the United States. This zoonotic organism is of particular interest due to its importance in pregnant women, in individuals with altered immune systems, and in reactivated ocular infections. Exposure to the parasite in humans is usually associated with consumption of raw or undercooked meat or by accidental ingestion of oocysts. It was hypothesized that veterinary students would have a greater chance at exposure to the parasite than an average population of undergraduate students due to increased contact with cats who are infected. A commercially available ELISA was used to examine serum samples from 336 students (252 veterinary students and 84 undergraduate students) at Virginia Polytechnic Institute and State University and the Virginia‐Maryland Regional College of Veterinary Medicine for serum IgG antibodies to T. gondii antigen. The prevalence of T. gondii in these subjects was 5.6% in veterinary school students (n = 252) and 2.4% in undergraduates (n = 84). There was no significant difference (P > 0.05) in the prevalence of T. gondii antibodies in veterinary versus undergraduate students. The overall prevalence of 4.8% in all students in this study reflects the continuing decline of antibodies to T. gondii in humans in the United States.  相似文献   
2.
A 4-month old, 200 kg, grey warmblood colt presented for a firm, non painful mass on the distal medial aspect of the left third metatarsus. Excisional biopsy revealed a diagnosis of haemangiosarcoma. Equine haemangiosarcoma is uncommon and only limited reports of successful treatment are available. The prognosis for survival is therefore considered to be poor. After two separate incidences of recurrence with incomplete excision of the tumour, intralesional treatment with cisplatin without excision or debulking was performed on three separate occasions. Intralesional cisplatin injection was performed at monthly intervals for three treatments. Four years post treatment with cisplatin, the horse remained in remission. This case report describes the diagnostic and treatment challenges for successful treatment of a primary haemangiosarcoma on the distal limb of a warmblood foal using intralesional cisplatin chemotherapy.  相似文献   
3.
In an on‐farm study, 40 weaned piglets aged 3 weeks were vaccinated with Lawsonia intracellularis vaccine orally, IM or IP while a fourth group remained unvaccinated. All vaccinated animals showed increased serum levels of L. intracellularis‐specific IgG antibodies, but significantly elevated concentrations of specific IgG, IgA and cytokines were generated in ileal mucosal secretions from the orally and IP vaccinated pigs when examined at 17 days after vaccination.  相似文献   
4.
Seminal plasma (SP) contains several types of compounds derived from the epididymides and accessory glands. The aim of this study was to examine the protein composition of different ejaculate fractions. Trial I: fractionated ejaculates were collected from two normal and two subfertile stallions. Samples containing pre‐sperm fluid and the first sperm‐rich jets (HIGH‐1), the main sperm‐rich portion (HIGH‐2), the jets with low sperm concentrations (LOW), and a combined whole‐ejaculate (WE) sample was centrifuged, and the SP was filtered and frozen. A part of each SP sample was stored (5°C, 24 h) with spermatozoa from HIGH‐2 and skim milk extender. Sperm motility was evaluated after storage in extender mixed with the stallion’s own SP or SP from one of the other stallions (sperm from a normal stallion stored in SP from a subfertile stallion and vice versa). Protein composition was analysed using reverse‐phase liquid chromatography (RP‐HPLC), N‐terminal sequencing and mass spectrometry. The area‐under‐the‐curve (AUC) was used for quantitative comparison of proteins within fractions. Trial II: semen samples were collected from seven stallions. Fractions with the highest (HIGH) and lowest (LOW) sperm concentrations and WE samples were examined using SDS‐PAGE and densitometry. No significant differences emerged between fractions in the AUC‐values of the Horse Seminal Protein‐1 (HSP‐1) and HSP‐2 peaks, or the peak containing HSP‐3 and HSP‐4 (HSP‐3/4). Levels of HSP‐1, HSP‐2 and HSP‐3/4 were not significantly correlated with total sperm motility, progressive sperm motility or average path velocity after storage. Significant differences between ejaculate fractions in the amount of different protein groups present in SP were not found in Trial I; but in Trial II, the proteins in the 60–70 kDa range were more abundant in LOW than in HIGH and WE, indicating that this band contained proteins derived mainly from the seminal vesicles, which produce most of the SP in LOW.  相似文献   
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We evaluated forage production patterns, weight gains and blood parameters when lambs (Ovis aries) and meat‐goat (Caprus hircus) kids were finished on a mixed sward of cocksfoot (Dactylis glomerata L.), red clover (Trifolium pratense L.) and white clover (Trifolium repens L.) with (SUP) and without (UNSUP) supplemental whole cottonseed (Gossypium hirsutum; WCS) in a replicated study. Botanical composition and energy/protein ratios of the sward varied with year and with time during the growing season. Swards had greater amounts of red clover relatively early and more cocksfoot later in the season. Suffolk (SX) lambs had the heaviest body weights, Katahdin (KA) lambs were intermediate, and meat‐goat (GX) kids were the lightest at the end of each year. Overall body weight gain followed a trend of SX > KA > GX, and WCS supplementation increased weight gain for all animals by 18%. Only in 2008 did SUP animals have higher blood urea nitrogen levels, which may indicate less efficient use of dietary nitrogen when grazing grass–legume pastures managed for high nutritive value compared with UNSUP animals. Gossypol in WCS did not affect blood packed cell volume between SUP and UNSUP lambs and meat‐goat kids. Suffolk lambs, Katahdin lambs and cross‐bred Boer meat‐goat kids finished on pasture with and without WCS supplementation produced desirable body weights for most ethnic markets in the USA.  相似文献   
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During the last decades, essential progresses in reproductive biotechnology were achieved, implying development of special spermatological techniques. The major problem was to set up simple, rapid, precise and adequate evaluation methods. The key aspect to be considered in all assays of sperm fertilizing function is capacitation. As not all spermatozoa respond to fertilizing conditions in a similar manner, it seems to be logical to assess samples via their response to these specific conditions. For the spermatological practice, the sensitivity of methodology for assessment and analysis of data with respect to differences in individual response, in heterogeneity of the population, and proper temporal characterization of the response is crucial for the improvement of evaluation procedures. Currently, most used statistical analytical tools in spermatology do not always fulfil these essential sensitivity requirements. We structured our paper concerning different fields of mathematical science (distribution analysis, fractal geometry, functional approximation and differentiation) related to the modern insights in sperm function analysis. The spectrum of methods we are going to review in this paper is restricted to basic ideas to illustrate how the accuracy and sensitivity of sperm evaluation assays may be improved by applying adequate elementary tools of the mathematical analysis.  相似文献   
9.
A diagnosis of dicoumarol toxicity in a herd of Friesian cattle was made following investigation of the deaths of three mature cows and eleven yearling heifers. Affected stock had been fed wrapped, bailed silage containing approximately 90% sweet vernal grass ( Anthoxanthum odoratum ). Sweet vernal grass contains coumarin, which can be converted to dicoumarol, a vitamin K antagonist, through the action of moulds. Most deaths were preceded by lethargy, severe anaemia and subcutaneous and internal haemorrhage. Dicoumarol toxicosis was suspected based on clinical signs, necropsy findings and prolonged prothrombin and activated partial thromboplastin times. Dicoumarol analysis of blood from affected animals and silage confirmed the diagnosis.  相似文献   
10.
Progress of essential steps of the capacitation is coordinated in the oviductal isthmus, where sperm are stored in close contact with the epithelium. A crucial capacitational event is the phosphorylation of sperm membrane proteins. Regulation of the tyrosine phosphorylation by the oviduct has not been examined in dog sperm yet. The aim of this work was to study the effect of dog sperm binding to porcine oviductal epithelium on capacitation‐induced cellular and molecular changes. Epithelial cells were stripped from the oviducts of post‐puberal sows and cultured for 5–7 days at 39°C and 5% CO2 on Biomatrix‐covered Chamber slides. Sperm washed through Percoll was co‐incubated with the oviductal epithelium cell cultures in a bicarbonate Tyrode's medium. During co‐incubation, sperm membrane changes, the state of tyrosine phosphorylation and motility were determined after 3, 30, 90, 180, 240 and 360 min. Significant increases in the percentage of capacitated and dead cells were observed in unbound sperm, while bound sperm remained uncapacitated, live and motile. An increasing tyrosine phosphorylation of tail proteins in bound, unbound and control sperm suspensions and a subsequent phosphorylation of head proteins in unbound and control sperm suspensions were observed. A significant difference regarding head phosphorylation (p < 0.05) was found between sperm bound to oviductal epithelium and unbound sperm. Binding occurred mainly in sperm with non‐ phosphorylated heads, while higher proportions of phosphorylated cells were found in unbound populations. The head phosphorylation progressed significantly during incubation in unbound spermatozoa (p < 0.05); however, it was suppressed in population of sperm attached to oviductal epithelium. Significant correlations between motility parameters related to hyperactivation and tail phosphorylation were found in unbound sperm. These observations support the hypothesis that spermatozoa with non‐phosphorylated heads preferentially attach to epithelial cells. It can be concluded that tyrosine phosphorylation of head membrane proteins and capacitation are delayed in canine spermatozoa being in closed contact with oviductal epithelium.  相似文献   
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