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The aim of this study was to evaluate the effect of porcine luteinizing hormone (pLH) given at oestrous onset in gilts, by different routes and doses, on the interval between onset of oestrus and ovulation (IOEO) and reproductive performance using a single fixed‐time artificial insemination (FTAI). A total of 153 gilts were submitted to oestrous detection at 8‐h intervals and assigned to three groups: control – without hormone application and inseminated at 0, 24 and 48 h after oestrous onset; VS2.5FTAI – 2.5 mg pLH by the vulvar submucosal route at oestrous onset and a single FTAI 16 h later; IM5FTAI – 5 mg pLH by the intramuscular route at oestrous onset and a single FTAI 16 h later. More VS2.5FTAI gilts (47.1%; p < 0.05) ovulated within 24 h after oestrous onset than control gilts (25.5%) whereas IM5FTAI gilts had an intermediate percentage (31.4%; p > 0.05). The IOEO tended to be shorter (p = 0.06) in VS2.5FTAI (30.2 ± 1.4 h) than in control (34.7 ± 1.4 h) gilts, but there was no difference (p > 0.05) between control and IM5FTAI (32.8 ± 1.4 h) gilts. Farrowing rate was not different (p > 0.05) among treatments. Total born piglets (TB) was lower (p < 0.05) in VS2.5FTAI (12.3 ± 0.4) than in control gilts (14.1 ± 0.4), whereas intermediate TB was observed in IM5FTAI gilts (13.3 ± 0.4). Due to the advancement of ovulation, reduction of the hormonal dose and the ease of application, the vulvar submucosal route would be the best option for FTAI protocols, but their negative impact on litter size remains to be elucidated. Taking into account the good fertility results obtained in IM5FTAI gilts whose ovulation was not advanced, the possibility of a single FTAI without any hormonal treatment should be further investigated, to establish reliable FTAI protocols for gilts.  相似文献   
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The use of cholesterol‐loaded cyclodextrin (CLC) on semen cryopreservation has been related with better sperm viability in several species; however, the effect on fertility is not known in donkey semen. Ejaculates (n = 25) from five donkeys were diluted in S‐MEDIUM with 0, 1, 2 or 3 mg of CLC/120 × 106 spermatozoa. Semen was frozen, and thawed samples were evaluated by computer‐assisted sperm analyser system (CASA), supravital test, hyposmotic swelling test and fluorescent dyes to assess the integrity of sperm membranes. Mares (n = 60) were inseminated with frozen‐thawed semen treated with the doses of 0 or 1 mg CLC. Percentages of sperm with progressive motility and with functional plasma membrane were greater (p < 0.05) in the CLC‐treated groups than in the control. Percentages of intact plasma membrane and intact plasma membrane and acrosome detected by fluorescent dyes were also greater (p < 0.05) in CLC‐treated groups. Although no difference (p > 0.05) in conception rates was detected between groups (control, 3/30, 10%; CLC‐treated, 1/30, 3.3%), fertility was low for artificial insemination programs in mares. Therefore, we firstly demonstrated that frozen semen treated with CLC in S‐MEDIA extender before freezing improves the in vitro sperm viability, but semen treated or not with CLC in S‐MEDIUM extender results in a very low conception rate in mares inseminated with thawed donkey semen.  相似文献   
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AIM: To determine the aetiology of a syndrome characterised by facial paralysis in calves (facial paralysis syndrome; FPS); describe the epidemiology of the syndrome on an affected case farm; and define the intra-farm prevalence of affected calves, and inter-farm prevalence of affected dairy farms, in the Franklin district of New Zealand.

CASE HISTORY AND CLINICAL FINDINGS: An investigation was carried out on a town-supply dairy farm experiencing an outbreak of FPS in calves during the autumn of 2007, following a previous outbreak during the spring of 2006; 21 calves were affected in both outbreaks. Post-mortem examinations of three affected calves revealed no infectious aetiological agent in neurological tissues despite tests for viruses, bacteria and Mycoplasma species. Tests on hepatic tissues for vanadium toxicity were inconclusive.

SURVEY OF DAIRY FARMS: Results from a postal survey of 177/325 (54%) farms established the yearly prevalence of affected farms, based on farmer diagnosis, was 11%, and there was a median two (range 1–25) affected calves on those farms. There was no evidence of spatial clustering of affected farms after accounting for the underlying farm density, or of an increase in the number of affected farms between 2003 and 2007.

CLINICAL RELEVANCE: Facial paralysis syndrome is an unusual condition that has not been reported in other districts of New Zealand or in other countries. It is probable that this syndrome will continue to occur at a low to moderate prevalence, and have a significant impact on a small number of farms.  相似文献   
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Experimental visualization and verification of a single-molecule rotor operating within a supramolecular bearing is reported. Using a scanning tunneling microscope, single molecules were observed to exist in one of two spatially defined states laterally separated by 0.26 nanometers. One was identified as a rotating state and the other as an immobilized state. Calculations of the energy barrier for rotation of these two states show that it is below the thermal energy at room temperature for the rotating state and above it for the immobilized state.  相似文献   
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Journal of Crop Science and Biotechnology - Herbicides belonging to the chemical group imidazolinones and the quinclorac herbicide are important to control weeds in flooded rice. The objective of...  相似文献   
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A 12-year-old Quarterhorse stallion was presented with a severe lameness in the left forefoot. There was a 3 cm diameter cavity in the sole that extended to the solar surface of the distal phalanx. Radiographs revealed an osteomyelitis and a sequestrum which probably developed following the prolonged topical application of 10 percent formalin. The sequestrum was removed and the infected bone curetted under general anaesthesia. The horse was shod with heart bar shoes on both front feet 7 days after the surgery. Eight months later, radiographs showed marked rotation of the distal phalanx despite continual shoeing with heart bar shoes. Surgical resection of the dorsal wall of the hoof at the toe removed the pressure applied by the laminar wedge, and combined with the stabilising and supporting action of the heart bar shoe, permitted realignment of the distal phalanx approximately 30 degrees closer to the normal skeletal axis by 26 days post-operatively. This case highlights some of the recent developments in the treatment of laminitis and suggests that effective treatment is possible if the value of the animal warrants the time and investment.  相似文献   
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A captive Malayan tapir was observed to have inappetence, weight loss, signs of depression, mild dehydration and diar rhoea. Haematological and serum biochemical tests showed anaemia, hypoproteinaemia, hyperfibrinogenaemia and neu-trophilia with a left shift. Ultrasonic examination of the abdomen under anaesthesia revealed a well-encapsulated abscess. The abscess was marsupialised to the ventral body wall. Culture of the pus produced a mixed bacterial growth. Antimicrobial therapy was based on bacterial sensitivity results. Follow-up ultrasonic examinations showed resolution of the abscess. Ninety-one days after surgery the tapir began regurgitating food and water. An abscess originating from the stomach and occluding the lumen of the duodenum was identified at surgery. The abscess ruptured during surgical manipulations and the tapir was euthanased.  相似文献   
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