Spatial configuration becomes more important with increasing habitat loss: a simulation study of environmentally-transmitted parasites     

Tyler R. Bonnell  Ria R. Ghai  Tony L. Goldberg  Raja Sengupta  Colin A. Chapman 《Landscape Ecology》2018,33(8):1259-1272

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Expression of Osteopontin (OPN) mRNA in Bovine Ovarian Follicles and Corpora Lutea     

B Brunswig-Spickenheier  AK Mukhopadhyay 《Reproduction in domestic animals》2003,38(3):175-181

The matricellular protein osteopontin (OPN) plays a role in various physiological processes, including angiogenesis and tissue remodelling. As these processes are essential for the maintenance of ovarian physiology, the aim of the study was to investigate the expression of OPN (mRNA) in ovarian cells and to evaluate whether it can be regulated by gonadotrophins. Using conventional RT‐PCR and real‐time PCR, we have detected and quantified OPN mRNA as well as glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH) mRNA expression in bovine granulosa, theca and luteal cells. In all cells examined, both genes were found in equal amounts and no striking variations in the expression could be observed between granulosa, theca and luteal cells. Furthermore, no effect on either OPN or GAPDH mRNA expression was evident after culturing ovarian cells in the presence of gonadotrophic hormones, although the cells were still highly responsive in terms of cAMP formation. Although neither variations between different cell types nor a regulation of OPN mRNA expression by gonadotrophic hormones could be detected, the high and unambiguous mRNA expression in steroidogenic cells suggests that OPN should be added to the growing list of intraovarian factors which may be involved in ovarian physiology.  相似文献   

Ovarian Follicular Dynamics in Buffalo Cows (Bubalus bubalis)   总被引：1，自引：0，他引：1  

A Ali  AK Abdel-Razek  S Abdel-Ghaffar  PS Glatzel 《Reproduction in domestic animals》2003,38(3):214-218

Follicular growth in Egyptian buffalo cows was monitored using genital tracts from 200 buffalo cows collected immediately after slaughter. According to the morphological appearance of the corpus luteum (CL), the corresponding oestrous cycle was divided into four stages: A (days 1–4), B (days 5–10), C (days 11–17) and D (days 18–21). Within these stages the follicular population on the ovaries was evaluated and the dominant follicle (DF) determined in all recovered ovaries. The functional status of the DF and the largest sub‐dominant follicles was examined by histological examination in 31 cases, and Radio Immunoassay (RIA) analyses for estradiol‐17β (E₂) and progesterone (P₄) was performed in the follicular fluid in 23 of the DF. The results showed that DFs changed their endocrine character within the stages of the oestrous cycle. The DFs between days 5 and 10 were functionally active (E₂‐dominant; non‐atretic) in most of the cases. Between days 11 and day 17 half of the DFs became functionally inactive (P₄‐dominant; atretic). At days 18–21 all of the DF became functionally active and non‐atretic. In the specimens that carried two large follicles one of them was regularly atretic and P₄‐dominant whereas the other was non‐atretic and E₂‐dominant. Between days 18 and 21 all ovaries examined showed at least one large follicle. These findings suggest that in most of the cases follicular dynamics occurs in two wave‐like patterns in the Egyptian buffalo cows.  相似文献   

Embryonic Signals and Survival   总被引：1，自引：0，他引：1  

AK Goff 《Reproduction in domestic animals》2002,37(3):133-139

The objective of this review is to give an overview of the signaling mechanisms between the conceptus and the mother before implantation. The interactions between the embryo and uterus are complex and essential for normal embryo development and implantation. Problems in the signaling mechanisms are thought to play a significant role in early embryonic mortality since a high rate of embryonic morality occurs during this period. This review will focus on the mechanisms involved in the development of the conceptus and the prevention of luteolysis. It is based primarily on what is known in ruminants but also refers to work in other species such as the mouse and primates.  相似文献   

Impact of Buserelin Acetate or hCG Administration on the Day of First Artificial Insemination on Subsequent Luteal Profile and Conception Rate in Murrah Buffalo (Bubalus bubalis)          下载免费PDF全文

AK Pandey  SPS Ghuman  GS Dhaliwal  SK Agarwal  JB Phogat 《Reproduction in domestic animals》2016,51(4):478-484

This study was designed to investigate the impact of buserelin acetate (BA) or human chorionic gonadotropin (hCG) administration on the day of first artificial insemination (AI) on subsequent luteal profile (diameter of corpus luteum (CL) and plasma progesterone) and conception rate in Murrah buffalo. The present experiment was carried out at two locations in 117 buffalo that were oestrus‐synchronized using cloprostenol (500 μg) administered (i.m.) 11 days apart followed by AI during standing oestrus. Based on treatment (i.m.) at the time of AI, buffalo were randomly categorized (n = 39 in each group) into control (isotonic saline solution, 5 ml), dAI‐BA (buserelin acetate, 20 μg) and dAI‐hCG (hCG, 3000 IU) group. Out of these, 14 buffalo of each group were subjected to ovarian ultrasonography on the day of oestrus to monitor the preovulatory follicle and on days 5, 12, 16 and 21 post‐ovulation to monitor CL diameter. On the day of each sonography, jugular vein blood samples were collected for the estimation of progesterone concentrations. All the buffalo (n = 117) were confirmed for pregnancy on day 40 post‐ovulation. The conception rate was better (p < 0.05) in dAI‐BA (51.3%) and dAI‐hCG (66.7%) groups as compared to their control counterparts (30.8%). Furthermore, the buffalo of dAI‐hCG group had improved (p < 0.05) luteal profile, whereas the buffalo of dAI‐BA group failed (p > 0.05) to exhibit stimulatory impact of treatment on luteal profile when compared to control group. In brief, buserelin acetate or hCG treatment on the day of first AI leads to an increase in conception rate; however, an appreciable impact on post‐ovulation luteal profile was observed only in hCG‐treated Murrah buffalo.  相似文献   

Boron Deficiency in Mango (Mangifera indica L.): A Cause Delineation Study in Acidic Soils of Maharashtra, India     

Muthiah Edward Raja  Somanahalli C. Anil Kumar  Sri Y. Raju 《Soil Science and Plant Nutrition》2005,51(5):751-754

Boron deficiency is a major production constraint of Mango cv Alphonso in western coast, Maharashtra, India. The soils are sandy-loam, light, acidic in reaction and receive high annual precipitation of above 2,500 mm. The leaf and soil B status was low with an average of 23 and 0.25 mg kg⁻¹ respectively. About 60% of the orchards were found to be deficient in B. The B adsorption study using Langmuir adsorption isotherm revealed that the adsorption capacity of B by these soils was low with an average adsorption maxima (b) of 16.62 μg g⁻¹ and bonding energy constant ( K ) of 0.09 mL μg⁻¹ making soil B susceptible to leaching. The Mango leaf N status was in excess range, which aggravated B deficiency through growth dilution. A significant negative correlation was observed between leaf B and leaf N (statistically significant at 1% level (p=0.01)). The free Al status of the soils was found to be fairly high, and its detrimental effect on root growth was observed which led to inefficient absorption of limited soil B by roots. The climatic conditions of Konkan like high humidity, high temperature and long sunshine hours also favored widespread incidence of B deficiency, low yield and poor quality. The response of Mango cv Alphonso to the B application was found to be more in foliar than in soil application.  相似文献   

Differential expression of toll‐like receptor mRNA in corneal epithelium of ruminants     

Sakthivel Dhanasekaran  Thandavan Arthanari Kannan  Gopal Dhinakar Raj  Krishnaswamy Gopalan Tirumurugaan  Angamuthu Raja  Kathaperumal Kumanan 《Veterinary ophthalmology》2010,13(4):270-274

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The Kendall Oration     

AK Sutherland 《Australian veterinary journal》1994,71(7):231-232

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Reply     

AK SUTHERLAND 《Australian veterinary journal》1994,71(9):310-310

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Trans-vaginal oocyte retrieval and subsequent in vitro production of embryos from a cow involuntarily culled     

Shaw DG  Bowles CM  Raja K  Lishman AW 《Journal of the South African Veterinary Association》1999,70(3):130-131

A Holstein cow of high genetic merit, in late lactation (205 days) and diagnosed with salpingitis (after 4 infertile services and veterinary consultation), was subjected to 1 trans-vaginal oocyte collection attempt, prior to slaughter. Of an estimated 10 follicles punctured, a total of 4 cumulus-oocyte complexes were retrieved. These were matured in vitro in a maturation medium for 24 hours. After 24 hours maturation, the oocytes were fertilised in vitro with Percoll-processed frozen/thawed imported semen, of the owner's choice. Fertilisation was achieved in a modified Tyrode's medium. At 18 hours post-insemination, the presumptive zygotes were transferred into culture in vitro in Charles Rosenkran's amino-acid medium and supplemented on Day 4 post-insemination with 10% foetal calf serum. All in vitro procedures were conducted in 50 microl medium droplets, under oil, in a humidified incubator at 38.5 degrees C in 5% CO2 in air. Three of the potential zygotes cleaved and, by Day 7 of culture, these had developed to the morula stage. The embryos were frozen in 1.5 M ethylene glycol and later transferred non-surgically to synchronised Holstein recipient heifers. One morula resulted in the only pregnancy and subsequent birth of a healthy heifer calf. An independent commercial company confirmed parentage through standard blood-typing assays. The genetic salvage of oocytes, for in vitro production of embryos, has potential benefits to the producer.  相似文献