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81.
SUMMARY: Infection of cattle with bluetongue and Douglas viruses was detected on the central and southern coast of New South Wales from January to April 1989. Bluetongue virus infection was found well south of areas of expected occurrence. Evidence is presented to support wind-borne dispersal of infected vectors, Culicoides brevitarsis , southwards from the Hunter Valley.  相似文献   
82.
Lyme disease has been recognized in humans since 1975 when it was associated with an outbreak of oligoarthritis in children in Lyme, Connecticut. Erythema chronicum migrans (ECM) is a clinical marker for the human disease, which usually appears within 3 to 32 days after an infected tick bite. Lyme disease is caused by spirochete, Borrelia burgdorferi, which is vectored by the hard ticks Ixodes dammini or Ixodes pacificus in the United States. In humans, Lyme disease has been found to cause a variety of clinical syndromes including cardiopathy, neuropathy, dermatopathy, and arthropathy. Human Lyme carditis is characterized by varying degrees of atrioventricular (AV) heart block that usually resolve regardless of therapy. Lyme disease has been reported in the dog as an arthropathy. This article reports a case of complete heart block and myocarditis in a dog with a positive titer for B burgdorferi, in which clinical and pathologic findings were similar to those seen in human Lyme myocarditis.  相似文献   
83.
To evaluate the age of fontanelle closure of normal kittens and the size of their lateral ventricles, 50 ultrasonographic examinations using the bregmatic fontanelle as an acoustic window were made. Seven kittens, laboratory animals, were included in the study. To verify the location of the lateral ventricle, two of the kittens were sacrificed as neonates. In one of them ink was injected prior to autopsy into one lateral ventricle under sonographic guidance. In a longitudinal study of five of the kittens, the skull depth and the depth of the central part of the lateral ventricle reproduced in a longitudinal view could be measured up to the age of about 5 months. During that period, the skull depth increased from a median value of 1.95 cm (1.92-1.98) in a seven-day-old cat to 2.58 cm (2.52-2.59) in a 154-day-old cat, while the afore-mentioned ventricle values increased from 0.3 mm to 1.1 mm.  相似文献   
84.
This study evaluates the cranial rectus abdominus muscle pedicle flap as the sole blood supply for the caudal superficial epigastric skin flap. This flap was composed of a cranially based rectus abdominus muscle pedicle flap that was attached to the caudal superficial epigastric island skin flap (including mammary glands 2 to 5) via the pudendoepigastric trunk. Selective angiography of the cranial epigastric artery in eight cadaver dogs proved that the arterial vasculature in the cranial rectus abdominus was contiguous with that in the caudal superficial epigastric skin flap. In the live dog study, three of six of the flaps failed because of venous insufficiency. Necrosis of mammary gland 2 occurred in two of six flaps. One of six flaps survived with the exception of the cranial most aspect of mammary gland 2. Angiography of the cranial epigastric artery proved that arterial blood supply to these flaps was intact. Histological evaluation of the failed flaps showed full-thickness necrosis of the skin and subcutaneous tissues, the presence of severe congestion, and venous thrombosis. Retrograde venous blood flow through the flap was inconsistent, and hence resulted in failure of this myocutaneous flap. Use of this flap for clinical wound reconstruction cannot be recommended.  相似文献   
85.
Simultaneous chylothorax and chylous ascites related to intestinal lymphangiectasia was diagnosed in a 4-year-old spayed female dog. Palliative pleural and peritoneal drainage was accomplished by placement of fenestrated silastic sheeting into surgically created diaphragmatic defects, and implantation of a pleuro-peritoneal venous shunt. The immediate postoperative period was complicated by acute renal failure secondary to postcaval thrombosis originating at the site of placement of the efferent pump catheter and extending to the level of the renal veins. Rapid resolution of this complication was accomplished with systemic anticoagulation. Clinical signs related to fluid accumulation resolved for 10 weeks after which acute decompensation occurred and the dog was euthanatized. Postmortem examination showed that reaccumulation of fluid was associated with migration of the efferent limb of the shunt from the caudal vena cava.  相似文献   
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The breeding of South American camelids is the main economic activity of the high Andean region of South America and it, is potentially, the most profitable resource in of the Puna environmental conditions of the Puna. The duration of the gestation in alpaca is 339.7 ± 12 days. The objective of the present work was to macroscopically and microscopically describe the ontogenic development of the splanchnic cavities of the alpaca and to determine the gestational time in which the post‐cranial ossification centers are observed in the embryos/fetuses of this species, from day 21 to 107 of gestation. The documentation of normal ontogenic development, which is vacant for this period, is of the utmost importance to understand the consequences of the alterations at the different gestational times, as well as for the estimation of the gestational age in the case of abortions. Forty‐seven alpaca specimens of both sexes, at different times of their gestational development, collected during slaughter at local slaughterhouses of the Department of Huancavelica, Peru, were evaluated. Specimens were assigned to seven groups according to their morphological characteristics. The embryogenesis in the alpaca was characterized by a series of changes comparable to those occurring in other mammals with similar gestational periods. Despite these similarities, species differences were found in some organs as stomach, which are observed too in adult individuals.  相似文献   
90.
Reproductive stage frost poses a major constraint for wheat production in countries such as Australia.However,little progress has been made in identifying key genes to overcome the constraint.In the present study,a severe frost event hit two large-scale field trials consisting of six doubled haploid(DH)wheat populations at reproductive stage(young microspore stage)in Western Australia,leading to the identification of 30 robust frost QTL on 17 chromosomes.The major 18 QTL with the phenotype variation over 9.5%were located on 13 chromosomes including 2 A,2 B,2 D,3 A,4 A,4 B,4 D,5 A,5 D,6 D,7 A,7 B and7 D.Most frost QTL were closely linked to the QTL of anthesis,maturity,Zadok stages as well as linked to anthesis related genes.Out of those,six QTL were repetitively detected on the homologous regions on 2 B,4 B,4 D,5 A,5 D,7 A in more than two populations.Results showed that the frost damage is associated with alleles of Vrn-A1 a,Vrn-D1 a,Rht-B1 b,Rht-D1 b,and the high copy number of Ppd-B1.However,anthesis QTL and anthesis related genes of Vrn-B1 a and Ta FT3-1 B on chromosomes 5 B and 1 B did not lead to frost damage,indicating that these early-flowering phenotype related genes are compatible with frost tolerance and thus can be utilised in breeding.Our results also indicate that wild-type alleles Rht-B1 a and Rht-D1 a can be used when breeding for frost-tolerant varieties without delaying flowering time.  相似文献   
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