The Effect of Pasture Nitrate Concentration and Concentrate Intake after Turnout on Embryo Growth and Viability in the Lactating Dairy Cow     

RA Laven  HJ Biggadike  & RD Allison 《Reproduction in domestic animals》2002,37(2):111-115

This study investigated the effects on embryo growth and survival rate of feeding heavily‐fertilised spring grass, containing high levels of quickly‐degradable nitrogen, to pregnant cows. Forty‐eight lactating Holstein cows between 2 and 8 weeks pregnant were turned‐out, after a one‐week transition period onto high‐ or low‐nitrate pasture and fed a high‐ or low‐concentrate supplement. Cows grazing the High nitrate pasture had significantly higher milk and plasma urea concentrations than cows grazing the Control pasture, while cows which were fed less concentrate had a notably higher plasma ammonia. However, there was no evidence that an increased quickly‐degradable nitrogen (QDN) intake from pasture affected embryo survival or growth from 20 days onwards. This suggests that the impact of turnout on fertility mainly affects ovulation, fertilisation and/or the early embryo.  相似文献   

Field Investigation of Perinatal Mortality in Friesian Cattle Associated with Myocardial Degeneration and Necrosis     

RD Murray  AJ Williams  IM Sheldon 《Reproduction in domestic animals》2008,43(3):339-345

Perinatal mortality and stillbirths were investigated in an extensively managed herd of Friesian cows and heifers calving over a 2‐year period: 504 cows were calved and 215 heifers. Cows were bred to Friesian and Jersey bulls using natural service. The perinatal fetal mortality rate was 7.5% for cows and 30% for heifers. An experienced stockman managed these calvings and veterinary assistance was required only on nine occasions. All stillborn fetuses were examined post‐mortem by the Veterinary Laboratories Agency, Carmarthen and no infectious agent was identified on any occasion. Thyroid hyperplasia was found in two fetuses. In blood samples taken from 10 late pregnant heifers, mean glutathione peroxidase values were 7.9 ± 1.7 IU/ml Packed Cell Volume (PCV). Tissues from eight fetuses were submitted to the University of Liverpool for histopathological examination; all presented lesions consistent with myocardial degeneration and necrosis of the left ventricle. Following treatment of 205 late pregnant heifers with sodium selenite and vitamin E, the overall perinatal mortality rate in these cattle fell to below 11%.  相似文献   

Sacral osteochondrosis in two German Shepherd Dogs   总被引：1，自引：1，他引：0  

KR Mathis  M Havlicek  JB Beck  RD Eaton-Wells  FM Park 《Australian veterinary journal》2009,87(6):249-252

Two young adult male castrated German Shepherd Dogs were referred for evaluation of intermittent episodes of hindlimb pain. Physical examination suggested lumbosacral stenosis, and plain radiographs and computed tomography revealed lesions consistent with sacral osteochondrosis. One dog had osteochondral fragments removed surgically; the other was managed conservatively. The surgically treated dog had complete resolution of clinical signs whereas the dog managed conservatively had repeated episodes of mild pain and received one short course of non-steroidal anti-inflammatory medication in 18 months. Sacral osteochondrosis has not been previously reported in Australia.  相似文献   

Sialomucin Complex (Muc4) Expression in Porcine Endometrium During the Oestrous Cycle and Early Pregnancy   总被引：1，自引：0，他引：1  

AD Ferrell  JR Malayer  KL Carraway  RD Geisert 《Reproduction in domestic animals》2003,38(1):63-65

The non‐invasive type of implantation in the pig is characterized by the maintenance of a thick glycocalyx coating on the uterine epithelial surface microvilli. Present study investigated the alteration in the sialomucin complex (Muc4) expression during the oestrous cycle and early pregnancy in the pig. Endometrial tissue samples were immunostained with the primary antibody to the Muc4 transmembrane subunit ASGP‐2. Muc4 immunostaining increased in the surface and glandular epithelia between days 5 and 10 of oestrous cycle. Immunostaining continued to increase on day 12 with the greatest intensity of uterine Muc4 immunostaining detected on day 15 of the oestrous cycle and early pregnancy. Endometrial Muc4 expression in cyclic gilts decreased dramatically during early proestrous but continued to remain abundant in the surface and glandular epithelium of pregnant gilts during the period of conceptus attachment to the uterine surface.  相似文献   

Compositional heterogeneity in the bottom 1000 kilometers of Earth's mantle: toward a hybrid convection model     

van der Hilst RD  Karason H 《Science (New York, N.Y.)》1999,283(5409):1885-1888

Tomographic imaging indicates that slabs of subducted lithosphere can sink deep into Earth's lower mantle. The view that convective flow is stratified at 660-kilometer depth and preserves a relatively pristine lower mantle is therefore not tenable. However, a range of geophysical evidence indicates that compositionally distinct, hence convectively isolated, mantle domains may exist in the bottom 1000 kilometers of the mantle. Survival of these domains, which are perhaps related to local iron enrichment and silicate-to-oxide transformations, implies that mantle convection is more complex than envisaged by conventional end-member flow models.  相似文献   

Egtved virus: occurrence of inapparent infections with virulent virus in free-living rainbow trout, Salmo gairdneri Richardson, at low temperature     

P. E. VESTERGÅRD JØRGENSEN 《Journal of fish diseases》1982,5(3):251-255

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Cilia and cilia-related disorders     

AC Johnstone  SR McGlashan  RD Jolly 《New Zealand veterinary journal》2013,61(1)

Abstract

Extract

Among the puzzling aspects of the recently described autosomal recessive polycystic kidney disease (ARPKD) of sheep (Johnstone et al 2005 Johnstone, AC, Davidson, BI, Roe, AR, Eccles, MR and Jolly, RD. 2005. Congenital polycystic kidney disease in lambs. New Zealand Veterinary Journal, 53: 307–314. [Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]) is the multiplicity of organ systems affected and the phenotypic variations that occur between the various animal species. It has been shown in studies of other inherited polycystic kidney disease syndromes that the normal gene products of a mutant are likely to be involved in ciliary structure and function. The studies that have led to this recognition can be expected to eventually provide the basis for a better understanding of the functioning of this organelle, and the pathogenesis of lesions in the related diseases.

It is well known that cilia are important in the perception of light, olfactory stimuli and sound and that motile cilia provide cell motility (e.g. sperm) and transport of mucus and other fluids. Recent research has indicated that the involvement of the primary cili-um/basal body complex is of central importance in the detection and cellular response to extracellular movement of fluid, critical phases of embryonic development, cell cycle regulation and maintenance of cell polarity.

Confocal microscopic studies of renal cyst epithelium in ovine ARPKD have shown that only 30% of cells have a cilium and that these are often truncated (McGlashan et al 2005 McGlashan, SR, Poole, CA, Stayner, C, Johnstone, AC, Eccles, MR and Jensen, CG. 2005. “Primary cilia in fibrosis associated with two models of polycystic kidney disease”. In Proceedings of the 45th Annual Conference of the American Society for Cell Biology December 10–14 [Google Scholar]). The observation, although preliminary, strongly supports the argument that the mutant gene in this disease of sheep normally encodes for a protein essential for primary ciliary function.  相似文献   

Porcine Conceptus Oct-4 mRNA Expression During Peri-implantation Development     

DS Spencer  JW Ross  MD Ashworth  RD Geisert  LF Rickords 《Reproduction in domestic animals》2006,41(6):571-572

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Rundschau     

Leib RD i. R. Dr Edmund 《Journal of pest science》1989,62(4):74-76

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Rundschau     

RD i. R. Dr. Edmund Leib 《Journal of pest science》1980,53(6):88-92

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