Floppy lamb syndrome — an inherited lower motor neuron disease in open-faced Romney lambs     

KH Parton  MG Collett 《New Zealand veterinary journal》2013,61(1)

  相似文献   

Bayesian Inference for Multistate ‘Step and Turn’ Animal Movement in Continuous Time     

A. Parton  P. G. Blackwell 《Journal of Agricultural, Biological & Environmental Statistics》2017,22(3):373-392

Mechanistic modelling of animal movement is often formulated in discrete time despite problems with scale invariance, such as handling irregularly timed observations. A natural solution is to formulate in continuous time, yet uptake of this has been slow. This lack of implementation is often excused by a difficulty in interpretation. Here we aim to bolster usage by developing a continuous-time model with interpretable parameters, similar to those of popular discrete-time models that use turning angles and step lengths. Movement is defined by a joint bearing and speed process, with parameters dependent on a continuous-time behavioural switching process, creating a flexible class of movement models. Methodology is presented for Markov chain Monte Carlo inference given irregular observations, involving augmenting observed locations with a reconstruction of the underlying movement process. This is applied to well-known GPS data from elk (Cervus elaphus), which have previously been modelled in discrete time. We demonstrate the interpretable nature of the continuous-time model, finding clear differences in behaviour over time and insights into short-term behaviour that could not have been obtained in discrete time.  相似文献   

An Update on Cystic Ovarian Degeneration in Cattle   总被引：4，自引：0，他引：4  

AT Peter 《Reproduction in domestic animals》2004,39(1):1-7

Cystic ovarian degeneration (COD) is considered to be one of the most important causes of reproductive failure in cattle. There is a severe economic loss to dairy industry because COD increases days‐open in the postpartum period and the culling rates. The disease process is a consequence of a mature follicle that fails to ovulate at the appointed time of ovulation in the oestrous cycle. This anovulatory follicular structure either regresses or persists as a follicular or luteal cyst depending upon its structural/functional characteristics. The cells lining the follicular cyst synthesize oestrogen that, in certain instances, forces the animal to exhibit clinical signs of nymphomania. Besides oestrogen production, as per recent findings, they are also capable of secreting varying amount of progesterone which may dictate their fate. The animals that carry a luteal cyst may tend to be in anoestrus as the higher amount of progesterone secreted by this luteinized structure may change the pattern of gonadotrophins’ secretion. Present findings suggest that perturbation of the hypothalamo‐hypophyseal‐ovarian (HHO) axis, due to many exogenous and endogenous factors, as the cause for anovulation. For example, it has been suggested that lack of hypothalamic or hypophyseal response to the positive feedback effect of oestrogens that are secreted by the dominant follicle as one of the many causes. The non‐physiological changes that occur in the receptor expression of the HHO axis for the hormones involved in maturation, deviation, dominance and ovulation of the follicle may be yet another cause. The changes that occur at the cellular and molecular level in the ovary (in response to the factors mentioned above) that contribute to anovulation remain to be documented. This approach would allow us to completely understand the disease process. Hitherto, hormonal preparations that release luteinizing hormone from the anterior pituitary or have luteinizing hormone‐like action are used to treat follicular cysts. GnRH belongs to the former group and human chorionic gonadotrophin (hCG) hormone forms the latter group. Treatment with a luteolytic agent, prostaglandin F_2α (PGF_2α), is successful if a luteal cyst is diagnosed properly. Many agents may be developed in the future if the cellular and molecular pathways of the disease process are delineated. This article will review recent advances in our understanding of the pathogenesis of COD and suggest direction for future studies to completely understand the disease mechanism. This review will also discuss the existing method of treatments for cysts and methods proposed for treatment of cysts that tend to be refractory in nature.  相似文献   

An enzyme-linked immunosorbent assay for canine C-reactive protein     

P D Eckersall  J G Conner  H Parton 《The Veterinary record》1989,124(18):490-491

  相似文献   

Brucella suis in three dogs: presentation,diagnosis and clinical management     

CC Kneipp  AM Rose  J Robson  R Malik  AT Deutscher  AK Wiethoelter  SM Mor 《Australian veterinary journal》2023,101(4):133-141

Brucella suis is an emerging, zoonotic disease predominantly affecting dogs and humans that engage in feral pig hunting in Australia and other countries. Although B. suis infection in dogs shares some clinical similarities to the host-adapted species (B. canis), B. suis remains an incompletely understood pathogen in dogs with limited published data on its pathogenesis and clinical features. This case series describes the presentations, diagnosis, and clinical management of B. suis infection in three dogs: (1) a bitch with dystocia, abortion and mastitis; (2) an entire male dog with septic arthritis and presumptive osteomyelitis; and (3) a castrated male dog with lymphadenitis. Unique features of these cases are reported including the first documented detection of B. suis from milk and isolation from lymph nodes of canine patients, as well as the follow-up of pups born to a B. suis-infected bitch. Consistent with previous reports, all three dogs showed a favourable clinical response to combination antibiotic therapy with rifampicin and doxycycline. Individually tailored drug regimens were required based on the clinical presentation and other factors, including owner expectations and compliance with therapy as well as a zoonotic risk assessment (generally considered low, except around time of whelping). The authors include their recommendations for the clinical management of dogs that are at-risk or seropositive for B. suis with or without clinical signs or laboratory-confirmed infection.  相似文献   

Handbook of Veterinary Drugs     

AT Hart 《Australian veterinary journal》1999,77(12):783-783

  相似文献   

Assessment of neuropeptide binding sites and the impact of biostable kinin and CAP2b analogue treatment on aphid (Myzus persicae and Macrosiphum rosae) stress tolerance     

Lucy Alford  Richard Marley  Anthony Dornan  Jean‐Sbastien Pierre  Julian AT Dow  Ronald J Nachman  Shireen A Davies 《Pest management science》2019,75(6):1750-1759

  相似文献   

OCT4 Expression in Outgrowth Colonies Derived from Porcine Inner Cell Masses and Epiblasts     

K Schauser  AT Jensen  M Schmidt  P Hyttel 《Reproduction in domestic animals》2011,46(3):385-392

The present study was conducted to test different methods for porcine inner cell mass (ICM) and epiblast isolation and to evaluate the morphology and expression of pluripotency genes in ICM‐ and epiblast‐derived outgrowth colonies (OCs) and passages thereof with particular attention on the relationship between OCT4 expression and embryonic stem cell (ESC)‐like morphology. A total of 104 zona pellucida‐enclosed and 101 hatched blastocysts were subjected to four different methods of ICM and epiblast isolation, respectively: Manual isolation, immunosurgery, immunosurgery with manual cleaning, or whole blastocyst culture. OCs were established on mouse embryonic fibroblast (MEF) cells and categorized according to morphology and OCT4 staining. Although all isolation methods resulted in ESC‐like OCs, immunosurgery with manual cleaning yielded significantly higher rates of ICM/epiblast attachment and subsequent ESC‐like morphology, whereas no significant difference was found between ICM and epiblasts with respect to these characteristics. All ESC‐like OCs showed nuclear OCT4 staining and expression of OCT4, NANOG and SOX2 as evaluated by RT‐PCR. Upon initial passages, the expression of pluripotency markers was, however, gradually lost in spite of maintained ESC‐like morphology. In conclusion, we have established a robust system for derivation of ESC‐like OCs from porcine ICM and epiblasts and we have shown that localization of OCT4 is associated with an ESC‐like morphology although this relationship is lost during early passages.  相似文献   

Viability and storage of bromeliad pollen   总被引：7，自引：1，他引：6  

E. Parton  I. Vervaeke  R. Delen  B. Vandenbussche  R. Deroose  M. De Proft 《Euphytica》2002,125(2):155-161

Several bromeliad species from two different subfamilies, were used to develop a reliable method to evaluate pollen viability. Pollen germination on a medium containing 20% sucrose, 0.001%H₃BO₃ and 0.5% agar was comparable to germination on a compatible stigma. Maximum germination was reached within 2 to 10 hours depending on the species. Based on this test, six species were considered as being good pollen donors with germination percentages between 49%and 83%. Furthermore, pollen from these species and cultivars could be stored in liquid nitrogen (–196 ^°C) without a considerable loss of viability. For all species, a dehydration period of 4 hours prior to cryopreservation and a rehydration period of 1 hour after cryostorage were essential. Greenhouse humidity influenced anther moisture content and cryostorability. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Modeling the effects of climatic and co2 changes on grassland storage of soil C     

Dennis S. Ojima  William J. Parton  David S. Schimel  Jonathan M. O. Scurlock  Timothy G. F. Kittel 《Water, air, and soil pollution》1993,70(1-4):643-657

We present results from analyses of the sensitivity of global grassland ecosystems to modified climate and atmospheric CO₂ levels. We assess 31 grassland sites from around the world under two different General Circulation Models (GCM) double CO₂ climates. These grasslands are representative of mostly naturally occurring ecosystems, however, in many regions of the world, grasslands have been greatly modified by recent land use changes. In this paper we focus on the ecosystem dynamics of natural grasslands. The climate change results indicate that simulated soil C losses occur in all but one grassland ecoregion, ranging from 0 to 14% of current soil C levels for the surface 20 cm. The Eurasian grasslands lost the greatest amount of soil C (～1200 g C m^?2) and the other temperate grasslands losses ranged from 0 to 1000 g C m^?2, averaging approximately 350 g C m^?2. The tropical grasslands and savannas lost the least amount of soil C per unit area ranging from no change to 300 g C m^?2 losses, averaging approximately 70 g C m^?2. Plant production varies according to modifications in rainfall under the altered climate and to altered nitrogen mineralization rates. The two GCM's differed in predictions of rainfall with a doubling of CO₂, and these differences are reflected in plant production. Soil decomposition rates responded most predictably to changes in temperature. Direct CO₂ enhancement effects on decomposition and plant production tended to reduce the net impact of climate alterations alone.  相似文献