The Insulin‐like Growth Factor System: a Key Determinant Role in the Growth and Selection of Ovarian Follicles? A Comparative Species Study   总被引：11，自引：0，他引：11  

S Mazerbourg  CA Bondy  J Zhou  P Monget 《Reproduction in domestic animals》2003,38(4):247-258

The aim of the present paper is to make a comparative study of the expression of the elements of the insulin‐like growth factor (IGF) system in different mammalian species and thus illuminate their potential role in the process of ovarian folliculogenesis in mammals. In most mammalian species, IGFs and IGFBPs (in particular IGFBP‐2 and IGFBP‐4) are considered, respectively, as stimulators and inhibitors of follicular growth and maturation. In mammalian species, IGFs might play a key role in sensitizing ovarian granulosa cells to FSH action during terminal follicular growth. Concentrations of IGFBP‐2 and IGFBP‐4 in follicular fluid strongly decrease and increase during follicular growth and atresia, respectively, leading to an increase and a decrease in IGF bioavailability, respectively. The decrease in these IGFBPs is because of a decrease in mRNA expression (IGFBP‐2) and an increase in proteolytic degradation by PAPP‐A in follicular fluid (IGFBP‐2, IGFBP‐4 and IGFBP‐5), and likely participates in the selection of dominant follicles. In contrast, levels and/or sites of expression of IGF‐I, IGF‐II, IGFBP‐4, IGFBP‐5 and type II receptor in follicular cells strongly differ between mammalian species, suggesting that these phenomena might play species‐specific or secondary roles in ovarian folliculogenesis.  相似文献   

The pathogenesis of the nervous syndrome of Phalaris aquatica toxicity in sheep   总被引：1，自引：0，他引：1  

CA BOURKE  MJ CARRIGAN  RJ DIXON† 《Australian veterinary journal》1990,67(10):356-358

The clinical signs displayed by 96 sheep affected by the nervous syndrome of Phalaris aquatica toxicity and 10 normal sheep injected intravenously with the phalaris alkaloid, 5-methoxy dimethyltryptamine (dose range 0.01 to 5.0 mg/kg), were observed. The distributions of phalaris indole-like cytoplasmic pigments in nuclei of the brains and spinal cords of 9 naturally affected sheep were determined microscopically. Based on the relationship between clinical signs and the central nervous system nuclei involved in their production, the distribution of phalaris indole-like pigments, and the pharmacology of dimethylated tryptamines, it is suggested that the nervous syndrome induced by Phalaris aquatica results from a direct action of phalaris alkaloids upon serotonergic receptors in specific brain and spinal cord nuclei.  相似文献   

Effects of Storing Pig Ovaries at 4 or 20°C for Different Periods of Time on the Morphology and Viability of Pre-Antral Follicles     

CM Lucci  LL Schreier  GM Machado  CA Amorim  SN Báo  JR Dobrinsky 《Reproduction in domestic animals》2007,42(1):76-82

The purpose of this study was to evaluate the effect of cooling ovarian tissue on pig pre-antral follicles. Ovaries were maintained in saline solution (0.9%) at 4 or 20 degrees C for 6, 12 or 18 h. After storage, pre-antral follicles were morphologically evaluated. While primordial follicles were not affected by the storage, the percentage of morphologically normal growing follicles was significantly reduced in ovarian tissue stored at 20 degrees C for 12 or 18 h. To test the viability of stored follicles, growing follicles isolated from ovaries stored at 4 degrees C for 18 h and at 20 degrees C for 6 h were cultured for 3 days. Follicles stored in either condition presented the same growth pattern in vitro as fresh follicles. We conclude that storage of pig ovaries at 4 degrees C for up to 18 h or at 20 degrees C for up to 6 h does not affect the morphology of growing follicles or their ability to grow in vitro.  相似文献   

Epigenetic Programming of Porcine Endometrial Function and the Lactocrine Hypothesis     

FF Bartol  AA Wiley  CA Bagnell 《Reproduction in domestic animals》2008,43(S2):273-279

Epigenetic programs controlling development of the female reproductive tract (FRT) are influenced by the effects of naturally occurring bioactive agents on patterns of gene expression in FRT tissues during organizationally critical periods of foetal and perinatal life. Aberrations in such important cellular and molecular events, as may occur with exposure to natural or manmade steroid or peptide receptor-modulating agents, disrupt the developmental program and can change the developmental trajectory of FRT tissues, including the endometrium, with lasting consequences. In the pig, as in other mammals, maternal programming of FRT development begins pre-natally and is completed post-natally, when maternal effects on development can be communicated via signals transmitted in milk. Studies involving relaxin (RLX), a prototypic milk-borne morphoregulatory factor (MbF), serve as the basis for ongoing efforts to identify maternal programming events that affect uterine and cervical tissues in the neonatal pig. Data support the lactocrine hypothesis for delivery of MbFs to neonates as a specific consequence of nursing. Components of a maternally driven lactocrine mechanism for RLX-mediated signalling in neonatal FRT tissues, including evidence that milk-borne RLX is delivered into the neonatal circulation where it can act on RLX receptor (RXFP1) -positive neonatal tissues to affect their development, are in place in the pig. The fact that all newborn mammals drink milk extends the timeframe of maternal influence on neonatal development across many species. Thus, lactocrine transmission of milk-borne developmental signals is an element of the maternal epigenetic programming equation that deserves further study.  相似文献   

Chronic pancreatitis with secondary diabetes mellitus treated by use of insulin in an adult California sea lion     

Meegan JM  Sidor IF  Steiner JM  Sarran D  Dunn JL 《Journal of the American Veterinary Medical Association》2008,232(11):1707-1712

CASE DESCRIPTION: A 21-year-old neutered male captive California sea lion developed chronic polyuria; polydipsia; polyphagia; accelerated development of existing cataracts; and frequent episodes of gastrointestinal upset including anorexia, signs of abdominal discomfort, diarrhea, and vomiting. CLINICAL FINDINGS: Chronic hypercholesterolemia, hypertriglyceridemia, hyperglycemia, and glucosuria were identified. During episodes of gastrointestinal abnormalities, transient hyperbilirubinemia and increased serum J-glutamyltransferase activities developed. Clinical findings strongly suggested chronic pancreatitis with secondary diabetes mellitus and intermittent cholestasis. Multiple diagnostic tests, including abdominal ultrasonography, serial hematologic and serum biochemical analyses, fecal examinations, urinalyses and bacteriologic culture of urine, measurement of serum fructosamine and insulin concentrations, and evaluation of thyroid and adrenal function, did not reveal any specific parasitic, endocrine, hepatic, or neoplastic etiologies. TREATMENT AND OUTCOME: For 1.5 years, the sea lion received once-daily administration of glargine insulin, gastrointestinal protectants, and a strict high-protein, low-fat diet. Daily monitoring of glucose regulation was achieved by training the sea lion to submit to blood and urine sampling. Glucose regulation ranged from fair to good, and clinical signs of diabetes mellitus lessened. Episodes of gastrointestinal upset still occurred, although the frequency and severity decreased. Ultimately, a severe episode developed, associated with diabetic ketoacidosis and sepsis, and the sea lion died. Severe fibrosing pancreatitis with exocrine and endocrine atrophy and abscesses arising from ectatic pancreatic ducts were found. Peripancreatic fibrosis caused stricture of the common bile duct, resulting in gallbladder distension without cholecystitis. CLINICAL RELEVANCE: Diabetes mellitus can occur secondary to chronic pancreatitis in California sea lions and insulin therapy should be considered.  相似文献   

Chronic gypsum fertiliser ingestion as a significant contributor to a multifactorial cattle mortality     

CA BOURKE  SJ OTTAWAY 《Australian veterinary journal》1998,76(8):565-569

Objective To assess the validity of claims that heavy metal contamination from an open-cut mine caused the death of 226 cattle on a nearby farm over a period of 18 months, and to investigate other possible contributing factors.
Procedure A retrospective assessment of previous investigations combinded with additional chemical analyses.
Results Extensive chemical analyses produced no evidence of heavy metal contamination associated with the mine. Analysis of bones indicated exposure to fluoride in greater than normal amounts. The main source of fluoride seems to have been gypsum that was included in a feed supplement and also ingested from fertiliser dumps on paddocks. The gypsum itself may have contributed significantly to the ill health. Other factors probably affected some classes of animals, notably the young calves.
Conclusions What originally seemed to be a disease problem of single aetiology probably was an expression of interacting multifactorial causes. This investigation has highlighted the potential toxicity of gypsum to livestock and the need for further studies to establish its basis.  相似文献   

Effects of body condition score (BCS) on steroid‐ and eicosanoid‐metabolizing enzyme activity in various mare tissues during winter anoestrus          下载免费PDF全文

MPT Owen  EN Ferjak  CA Cavinder  KJ McCarty  KC Yankey  CG Hart  DD Burnett  TTN Dinh  CO Lemley 《Reproduction in domestic animals》2018,53(2):296-303

The objective of this study was to determine the activity of steroid‐ and eicosanoid‐metabolizing enzymes in horses with varying BCSs. The BCSs of twenty non‐pregnant, anoestrous mares were determined prior to euthanasia, and tissue samples were collected from the liver, kidney, adrenal gland, ovary and endometrium. Cytochrome P450 1A (CYP1A), 2C (CYP2C), 3A (CYP3A) and uridine 5′‐diphospho‐glucuronosyltransferase (UGT) activities were determined using luminogenic substrates. The MIXED procedure of SAS was used to test the effect of BCS on enzyme activity and differences between tissues. Activity of CYP1A in adrenals was increased (p ≤ .05) in BCS 5 versus BCSs 4 and 6. Activity of CYP1A in the liver was increased (p = .05) in BCS 4 versus BCSs 5 and 6. Activity of CYP1A was 100‐fold greater (p < .0001) in the liver than in the adrenal, ovary and kidney. Activity of CYP2C was 100‐fold greater (p < .0001) in the liver than in the adrenal, ovary and endometrium. Activity of CYP3A was only detectable in the liver. Activity of UGT in the kidney was decreased (p = .02) in BCS 4 versus BCSs 5 and 6. Activity of UGT was threefold greater (p < .0001) in the liver than in the kidney, whereas activity of UGT was ninefold greater (p < .0001) in the kidney than in the ovary and endometrium. In general, BCS did not alter the activity of steroid‐ and eicosanoid‐metabolizing enzymes in horses. However, tissue differences in these enzymes indicated abundant hepatic metabolism in horses, which is similar to other livestock species.  相似文献   

Sex identification in the eastern blue‐tongued lizard (Tiliqua scincoides White,ex Shaw, 1790) using morphometrics          下载免费PDF全文

CA Phillips  JB Roffey  E Hall  RSP Johnson 《Australian veterinary journal》2016,94(7):256-259

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The Recipients' Parity Does Not Influence Their Reproductive Performance Following Non‐Surgical Deep Uterine Porcine Embryo Transfer          下载免费PDF全文

EA Martinez  A Nohalez  CA Martinez  I Parrilla  J Vila  I Colina  M Diaz  J Reixach  JL Vazquez  J Roca  C Cuello  MA Gil 《Reproduction in domestic animals》2016,51(1):123-129

With the development of the non‐surgical deep uterine (NsDU) embryo transfer (ET) technology, the commercial applicability of ET in pigs is now possible. There are, nevertheless, many factors that influence NsDU‐ET effectiveness that need to be addressed. The aim of this study was to evaluate the effects of the weaned recipients' parity on fertility and prolificacy following NsDU‐ET. The recipients (n = 120) were selected based on their reproductive history and body condition and grouped into three categories according to their parity: primiparous sows, sows of parity 2 and sows of parities from 3 to 5. Thirty fresh embryos (morulae and unhatched blastocysts) were non‐surgically transferred into one uterine horn of each recipient. It was possible to insert the NsDU‐ET catheter through the cervix along a uterine horn in 98.3% of the recipients. The parity had no influence on the difficulty grade of the insertions or on the percentage of correct insertions. The cervix and uterine wall were not perforated during the insertions, and vaginal discharge was not observed after transfer in any of the recipients. There were no differences in the pregnancy rates (74.8%), farrowing rates (71.2%) or litter sizes (9.6 ± 3.3) between groups. Also, there were no differences between groups regarding to the piglets' birthweights or piglet production efficiency. In conclusion, these results demonstrate that weaned sows from parity 1 to 5 are appropriate to be used as recipients in NsDU‐ET programs, which increase the possibilities for the utilization of ET in the recipient farms.  相似文献   

不同日龄混合柄瘤蚜茧蜂对寄主虫龄的选择及子代蜂发育表现     

曹林  李保平  孟玲 《南京农业大学学报》2011,34(4)

对同一头混合柄瘤蚜茧蜂雌蜂连续观察5 d,比较其对蚕豆蚜若蚜和成蚜的选择,并观察了子代蜂的发育特性。结果表明:5日龄蜂对不同虫龄蚜虫的寄生率无显著差异,子代蜂羽化率和雌性比亦无显著差异,但寄生2、3龄若蚜的子代雌蜂体型显著大于寄生其他蚜虫的子代雌蜂,寄生3龄若蚜的子代雄蜂显著大于寄生成蚜的子代雄蜂。在其他日龄(1～4)蜂中,1、4日龄蜂对不同龄若蚜的寄生率无显著差异,但均高于对成蚜的寄生,2、3日龄蜂对2龄若蚜的寄生偏好显著高于对更高虫龄的寄生;3日龄蜂的子代蜂羽化率在各虫龄蚜虫之间无显著差异,其他日龄蜂寄生低龄若蚜的子代羽化率高于寄生较高虫龄蚜虫;寄生中间龄期若蚜(3、4龄)的子代蜂雌性比显著高于寄生1龄或成蚜的子代蜂;1日龄蜂子代雌蜂体型在不同虫龄蚜虫间无显著差异,但2～4日龄蜂寄生2、3龄若蚜的子代雌性体型大于寄生1龄、4龄或成蚜的子代雌蜂;1、2日龄蜂的子代雄蜂体型在各虫龄蚜虫间无显著差异,3、4日龄蜂寄生中间龄期若蚜的子代雄性体型大于寄生1龄若蚜或成蚜。根据本研究结果推测,与低龄蜂相比高龄蜂对寄主品质要求更高,其幼虫对寄主的调节能力更强。  相似文献