The Establishment of Early Pregnancy in Cows     

DC Wathes  RS Robinson  GE Mann  GE Lamming 《Reproduction in domestic animals》1998,33(3-4):279-284

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Corpus Luteum–Endometrium–Embryo Interactions in the Dairy Cow: Underlying Mechanisms and Clinical Relevance     

RS Robinson  AJ Hammond  DC Wathes  MG Hunter  GE Mann 《Reproduction in domestic animals》2008,43(S2):104-112

Conception rates of dairy cows are currently declining at an estimated 1% every year. Approximately, 35% of embryos fail to prevent luteolysis during the first three weeks of gestation. Interactions between the corpus luteum, endometrium and embryo are critical to the successful establishment of pregnancy and inadequacies will result in the mortality of the embryo. For example, as little as a one day delay in the post-ovulatory rise of progesterone has serious consequences for embryo development and survival. Recently, we found that LH support, degree of vascularization and luteal cell steroidogenic capacity were not the major factors responsible for this luteal inadequacy, but are nevertheless essential for luteal development and function. Progesterone acting on its receptor in the endometrium stimulates the production of endometrial secretions on which the free-living embryo is dependent. However, their exact composition and effects of inadequate progesterone remains to be determined. The embryo is recognized through its secretion of interferon tau (IFNT), which suppresses luteolytic pulses of prostaglandin F_2α. In the cow, it is most likely that IFNT inhibits oxytocin receptor up-regulation directly and does not require the prior inhibition of oestrogen receptor α (ESR1). Unravelling the precise luteal-endometrium and embryo interactions is essential for us to understand pregnancy establishment and development of strategies to reverse the declining fertility of dairy cows.  相似文献   

Cattle herd inspections and fly trapping for the detection of the Old World screw‐worm fly (Chrysomya bezziana)     

R Urech  S Muharsini  RS Tozer  Sumartono  PE Green  GW Brown  JP Spradbery  DG Mayer  Y Tack Kan  A Kison 《Australian veterinary journal》2014,92(1-2):28-32

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Lupinosis in yearling cattle     

JT MACKIE  RS RAHALEY  R BENNETT 《Australian veterinary journal》1992,69(7):172-173

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Simulation of the economic impact of proliferative enteritis on pig production in Australia   总被引：2，自引：0，他引：2  

PK HOLYOAKE  BP MULLAN†  RS CUTLER 《Australian veterinary journal》1996,73(3):89-92

The economic impact of proliferative enteritis (PE) on an ‘average’ pig farm was calculated using the AUSPIG decision support system. Inputs were modelled on actual cases of PE, in which affected herds suffered from depressed growth rate, decreased feed efficiency and stock losses. The costs associated with non-haemorrhagic PE and proliferative haemorrhagic enteropathy ranged from $15/sow/yr to $141/sow/yr, respectively, depending on the clinical severity of the disease, incidence of infection and the type of medication strategy used to treat and control the disease.  相似文献   

Activation of Zona‐Free Buffalo (Bubalus bubalis) Oocytes by Chemical or Electrical stimulation,and Subsequent Parthenogenetic Embryo Development     

A George  RA Shah  R Sharma  P Palta  SK Singla  RS Manik  MS Chauhan 《Reproduction in domestic animals》2011,46(3):444-447

Parthenogenetic activation using zona‐free oocytes offers an alternative model that could be applied to develop protocols for the activation of reconstructed embryos for cloning. The aim of this study was to compare the efficacy of different methods for the activation of zona‐free buffalo oocytes in terms of their effects on the developmental competence of parthenogenetic embryos. The effects of zona removal on parthenogenetic activation and in vitro developmental competence of metaphase II oocytes were also examined. All activation methods were followed by incubation of 2 mm 6‐dimethylaminopurine (6‐DMAP) for 4 h. Out of three different pulse strengths (1.2, 2.1 or 3.3 kV/cm) used, 2.1 kV/cm resulted in the highest blastocyst rate (25.3%). On comparing different chemical agents and electric pulse, highest blastocyst rate was observed for calcium ionophore (CaI) (28.6%) followed by ethanol (25.0%), electric pulse (22.5%) and combined CaI and ethanol treatment (16.7%) although differences among them were not significant. Furthermore, a significantly reduced developmental potential was observed in zona‐free oocytes when compared to zona‐intact ones up to the blastocyst stage (44.3% vs 27.1%). In conclusion, zona‐free buffalo oocytes can be successfully activated for parthenogenetic development using chemical or electrical stimulation. Out of different agents examined, CaI followed by 6‐DMAP resulted in the highest blastocyst rate.  相似文献   

Clinical use of atracurium in horses undergoing ophthalmic surgery     

JM  Senior  KJ Robinson  AHA Dugdale  CM Price  WA Adams  RS Jones 《Veterinary anaesthesia and analgesia》2001,28(4):207-208

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Effect of Sodium Nitroprusside,a Nitric Oxide Donor,and Aminoguanidine,a Nitric Oxide Synthase Inhibitor,on In Vitro Development of Buffalo (Bubalus bubalis) Embryos     

S Saugandhika  D Kumar  MK. Singh  R Shah  T Anand  MS Chauhan  RS Manik  S K Singla  P Palta 《Reproduction in domestic animals》2010,45(5):931-933

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Oocyte viability and cortical activation under different salt solutions in Prochilodus lineatus (Teleostei: Prochilodontidae)          下载免费PDF全文

DC Ribeiro  JMA Chagas  C Bashiyo‐Silva  RS Costa  R Veríssimo‐Silveira  A Ninhaus‐Silveira 《Reproduction in domestic animals》2017,52(6):932-938

This study aimed to evaluate the effect of five salt solutions in the maintenance of morphological features of cortical alveolus, hydration and fertilization capacity of Prochilodus lineatus oocytes. For this purpose, five saline solutions were tested: Ringer's solution, Ringer's lactate solution, Hank's balanced salt solution (HBSS), Hank's balanced salt solution without calcium (HBSS without calcium) and solution for salmonid eggs. Oocytes were maintained for 2 hr in saline solution with controlled temperature subsequently evaluated for hydration, cortical activation and fertilization ability. In the evaluation of the fertilization ability, two controls were used: C1—fertilized oocytes after extrusion—and C2—oocytes kept in ovarian fluid and fertilized after 2 hr. There was a significant reduction in the viability of oocytes C2 (28.8% ± 12.9%) compared to C1 (65.3% ± 26.7%), and no significant differences were found between treatments HBSS and HBSS without calcium and C2. Only HBSS and HBSS without calcium maintained the non‐activated state of the gametes, with a fertilization rate of 16.4% ± 6.7% and 5.6% ± 2.3%, respectively; however, they did not extend the viability of oocytes, such that they continued to undergo degradation during the storage period, similar to oocytes retained only in ovarian fluid.  相似文献   

A diagnostic dilemma: detecting proliferative enteritis in pigs at slaughter     

PK HOLYOAKE  RS CUTLER  IW CAPLE 《Australian veterinary journal》1994,71(9):308-309

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