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51.
Objective To report the rapid transmission of bovine ephemeral fever ( BEF) virus from north-western New South Wales south to the Victorian border in January 2008 and to present data that suggests an uncommon meteorological event caused this rapid southward dispersal of vectors. Procedure The locations of reported clinical cases, data from sentinel herds and results from a survey of cattle in the southern affected area were examined to delineate the distribution of virus transmission. Synoptic weather charts for January 2008 were examined for meteorological conditions that may have favoured movement of vectors in a southerly direction. Results Cases of BEF and exposure to BEF virus in NSW were confirmed west of the Great Dividing Range, extending from the Queensland border to Finley, on the far North Coast and around the Hunter Valley. A low-pressure system moved south across the state on 18–19 January 2008, preceding the first cases of BEF in the south of NSW by 1–2 days. Conclusion Heavy rainfall in December 2007 provided a suitable environment for vector breeding, resulting in the initiation of and support for continuing BEF virus transmission in north-western NSW. The movement of a low-pressure system south across central western NSW in mid-January 2008 after the commencement of BEF virus transmission in the north-west of the state provided a vehicle for rapid southward movement of infected vectors.  相似文献   
52.
AIM: To investigate the anthelmintic properties of New Zealand native flax (Phormium tenax) for cattle, using a faecal egg count reduction test (FECRT).

METHODS: Twenty-six heifer calves with high (>300 epg) faecal nematode egg counts (FEC) were paired into two groups and fed either chopped flax leaves ad libitum, or barley straw at an equivalent dry matter (DM) rate, from Day 0–7; all were supplemented with 1.5 kg/head/day cereal feed supplement. On Days 8–10, all heifers were fed a common diet of 3.5 kg DM/ head/day barley straw and 1.5 kg/head/day cereal feed supplement. Heifers were weighed and faecal samples were collected on Days —6, 0, 7, and 10; samples were analysed in triplicate for FEC. The nutritive value of the flax and straw was analysed.

RESULTS: Both the flax and straw had low dry matter digestibility (DMD) and protein content. Although the flax-fed claves grew more than the controls, this may have been related to gut fill. Total daily faecal egg output was similar for flax and straw groups on Day 7 (14.7 vs 15.0 x 106 eggs/day, respectively) and Day 10 (14.9 vs 15.1 x 106 eggs/day, respectively). There was no difference in the change in FEC with time between the calves fed flax or straw diets.

CONCLUSION: Consumption of flax leaves did not reduce FEC in calves with a mixed nematode infection.  相似文献   
53.
In this study, we explored the potential utility of the human‐focused FilmArray® Respiratory Panel for the diagnosis of a broad range of influenza viruses of veterinary concern as compared with the standard portfolio of recommended TaqMan®‐based diagnostic tests. In addition, we discuss some potential operational advantages associated with the use of such integrated sample extraction, amplification and analysis devices in the context of a future long‐term, dual‐role strategy for the detection of emergency diseases of both human and veterinary concern.  相似文献   
54.
Distributing animals from a single breeding program to a global market may not satisfy all producers, as they may differ in market objectives and farming environments. Analytic hierarchy process (AHP) is used to estimate preferences, which can be aggregated to consensus preference values using weighted goal programming (WGP). The aim of this study was to use an AHP-WGP based approach to derive desired genetic gains for rainbow trout breeding and to study whether breeding trait preferences vary depending on commercial products and farming environments. Two questionnaires were sent out. Questionnaire-A (Q-A) was distributed to 178 farmers from 5 continents and used to collect information on commercial products and farming environments. In this questionnaire, farmers were asked to rank the 6 most important traits for genetic improvement from a list of 13 traits. Questionnaire B (Q-B) was sent to all farmers who responded to Q-A (53 in total). For Q-B, preferences of the 6 traits were obtained using pairwise comparison. Preference intensity was given to quantify (in % of a trait mean; G%) the degree to which 1 trait is preferred over the other. Individual preferences, social preferences, and consensus preferences (Con-P) were estimated using AHP and WGP. Desired gains were constructed by multiplying Con-P by G%. The analysis revealed that the 6 most important traits were thermal growth coefficient (TGC), survival (Surv), feed conversion ratio (FCR), condition factor (CF), fillet percentage (FIL%), and late maturation (LMat). Ranking of traits based on average Con-P values were Surv (0.271), FCR (0.246), TGC (0.246), LMat (0.090), FIL% (0.081), and CF (0.067). Corresponding desired genetic gains (in % of trait mean) were 1.63, 1.87, 1.67, 1.29, 0.06, and 0.33%, respectively. The results from Con-P values show that trait preferences may vary for different types of commercial production or farming environments. This study demonstrated that combination of AHP and WGP can be used to derive desired gains for a breeding program and to quantify differences due to variations market demand or production environment.  相似文献   
55.
56.
The objective of this study was to evaluate the quality of chilled dog semen processed with extenders containing various concentrations of N‐acetyl‐L‐cysteine (NAC). Ejaculates from five dogs were collected, pooled and evaluated for concentration, motility, rapid steady forward movement (RSF‐movement), viability, acrosomal integrity and by the hypo‐osmotic swelling test (HOST). In addition, superoxide anion (O2‐?) production, hydroxyl radicals (OH?) and total reactive oxygen species (tROS) were determined. The pool was divided into five aliquots, which were diluted to a final concentration of 66.66 × 106 spermatozoa/ml with Tris‐glucose‐egg yolk extender containing one of the following concentrations of NAC (0, 0.5, 1, 2.5 or 5 mm ). The semen aliquots were chilled and preserved at 4°C. Semen quality was evaluated after rewarming at 72 h. Sperm motility was significantly higher with the 0.5 mm concentration compared with the control group (p = 0.001). Rapid steady forward movement was higher with the 0.5 and 1 mm concentrations compared with the control and 5 mm group (p < 0.001). Viability and HOST percentages were not significantly altered. Compared with the control, the 5 mm concentration showed significantly reduced percentages of spermatozoa with normal acrosomes (p = 0.049). None of the ROS values at 72 h were significantly affected by the presence of NAC in semen extenders, although all NAC concentrations showed lower O2‐? and OH? values compared with the control. Only the concentrations of 1 and 5 mm inhibited the significant increase of tROS values after 72 h, compared with the fresh semen value. In conclusion, NAC supplementation of semen extenders is beneficial to semen motility of canine spermatozoa during chilling with the 0.5 mm concentration being the most effective, although no significant ROS inhibition was observed at 72 h.  相似文献   
57.
The present studies were undertaken to examine the effect of tumour necrosis factor (TNF) alpha on prostaglandins (PGs) F(2alpha) and E(2) release by cultured porcine endometrial cells harvested on days 13-16 after oestrus in comparison to stimulation with oxytocin (OT) and luteinizing hormone (LH). A time-dependent effect of TNFalpha (10 ng/ml) on PGF(2alpha) release was observed in stromal and luminal epithelial cells. Moreover, TNFalpha increased PGF(2alpha) secretion from both endometrial cell types with effective concentrations of 1 (p < 0.05), 10 and 50 ng/ml (p < 0.01). The effect of TNFalpha (10 ng/ml) on endometrial PGF(2alpha) and PGE(2) release was compared with OT (100 nmol/l) and LH (100 ng/ml). All factors affected PGF(2alpha) secretion from stromal cells, however, the stimulation tended to be more potent after OT and LH (p < 0.01) than after TNFalpha (p < 0.05) treatment. In epithelial cells, only TNFalpha was able to stimulate PGF(2alpha) release (p < 0.001). PGE(2) secretion from stromal cells increased after incubation with TNFalpha and OT (p < 0.05). Only LH stimulated PGE(2) release from epithelium (p < 0.001), and its action was very effective when compared with TNFalpha or OT (p < 0.01). Summarizing, TNFalpha induces both PGs secretion from cultured porcine endometrium, but preferentially stimulates PGF(2alpha) release from luminal epithelial cells. Therefore, similarly to OT and LH, TNFalpha may be considered as a potential modulator of endometrial PGF(2alpha) production during luteolysis in the pig.  相似文献   
58.
Administration of hormones to synchronize oestrus is a useful tool in animal breeding. However, exogenous ovarian stimulation may be detrimental to reproductive function. This study was aimed to examine whether an oestrus synchronization with PGF2α/eCG/hCG could affect luteal P4 synthesis in early pregnant gilts. Corpora lutea (CLs) were collected on days 9, 12 and 16 of pregnancy from gilts with natural (n = 16) and synchronized (n = 18) oestrus and analysed for (i) the expre‐ssion of steroidogenic acute regulatory protein (StAR), cytochrome P450 family 11 subfamily A polypeptide (CYP11A1), and 3β‐hydroxysteroid dehydrogenase (3βHSD); (ii) the concentration of P4 in the luteal tissue and blood; and (iii) the expression of luteinizing hormone receptors (LHR) and oestrogen receptors (ERα and ERβ). Additionally, the effect of LH on P4 secretion from CL slices collected from synchronized and naturally ovulated animals has been studied in vitro. PGF2α/eCG/hCG administration increased mRNA expression of StAR, CYP11A1, 3βHSD, and LHR on day 9 and CYP11A1 and LHR on day 12 of pregnancy compared with the control group (p < 0.05). CYP11A1, 3βHSD, LHR, ERα and ERβ proteins were not affected by synchronization; only StAR protein increased in hormonally treated animals (p = 0.017). The concentration of P4 in luteal tissue was greater on day 9 (p < 0.01), but lower on day 16 (p < 0.05) in gilts with hormonally induced oestrus compared with control animals. Blood serum levels of P4 were lower in synchronized than control gilts (p < 0.001). Synchronization did not affect LH‐stimulated P4 secretion from luteal slices; however, greater basal concentration of P4 in incubation medium was detected for CLs collected from synchronized than control gilts (p < 0.05). In conclusion, synchronization of oestrus with PGF2α/eCG/hCG protocol in gilts did not impair the expression of luteal P4 synthesis system, although decreased P4 concentration in the blood.  相似文献   
59.
Objective   To evaluate the effect of a non-occlusive dressing incorporated in a 3-layer bandage on second intention healing of wounds of the distal portion of the limb.
Study Design   Untreated wounds in 33 adult horses used in four studies using the same wound-healing model conducted over 5 years.
Methods   Standardised, full-thickness wounds were made in the skin overlying the dorsomedial aspect of the mid-metacarpus; 17 horses were bandaged with a non-occlusive dressing covered by gauze-coated cotton wool that was compressed with adhesive tape; 16 horses were left unbandaged. Wounds were photographed weekly for 9 weeks and the images were analysed electronically.
Results   There were significant effects associated with bandage (P < 0.0001), week (P < 0.001), and bandage by week interaction (P < 0.0001). There was no difference in wound area at the first time-point after wound creation (P = 0.38). After week 1, there was a difference between bandaged and unbandaged wounds in wound area at each measurement until the end of the study. Bandaged wounds showed greater and more prolonged retraction. Unbandaged wounds retracted for 2 weeks before beginning to contract, whereas bandaged wounds continued to retract for 3 weeks. In bandaged wounds excess granulation tissue required regular trimming, but not in unbandaged wounds. There was no difference between groups in the total days to healing or the overall rate of healing.
Conclusions   These results should be treated with caution until validated with contemporaneous, controlled studies. Covering a wound with a non-occlusive dressing in a 3-layer bandage led to greater wound retraction, modulated the rate of wound contraction and promoted excessive granulation tissue. If excessive granulation tissue is excised regularly, bandaging has no effect on total time to healing.  相似文献   
60.
The objectives of the present study were to investigate the bacteria accompanying hydrosalpinx of the buffalo cow and investigate the correlation between bacterial infection of the uterus and hydrosalpinx. Buffalo cows’ reproductive tracts were collected from Mosul abattoir. A total 385 uterine samples were examined of which 25 were having hydrosalpinx. Swabs for bacteriology, fluid for cytology and biopsies for histopathology were collected from the hydrosalpinx and the uterus from each samples included in this study. Results of this study indicated high prevalence of hydrosalpinx (6.5%) including unilateral (n = 19; 76%) and bilateral (n = 6; 24%) hydrosalpinx. Although 16 samples (64%) of the hydrosalpinx samples had no bacterial growth, the most prevalent bacteria recovered from hydrosalpinx were Corynebacterium hemolyticum and Actinomyces bovis, 42.8% and 28.6%, respectively. The most prevalent bacteria in the uterus were Archanobacterium pyogenes (18.5%), Staphylococcus aureus (14.8%), and Listeria monocytogenes (11.0%). Higher rates of leukocytes infiltration (p < 0.01) were observed in the uterine discharge than hydrosalpinx. A significant (p < 0.01) increase in lymphocytes was found in uterine discharge. Microscopic examination of the hydrosalpinx showed mucosal atrophy and dilatation of oviductal lumen without any signs of inflammation. It could be concluded that there is no correlation between bacteria isolated from uterus and hydrosalpinx. No association was found between bacteriological cultures and hydrosalpinx. Inflammation of the uterine tissue could be extended to utero‐tubal junction producing local inflammation resulting in fibrosis and tubal obstruction. The obstruction in the lumen of the oviducts resulted in accumulation of fluid.  相似文献   
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