Research@Lincoln
    • Login
     
    View Item 
    •   Research@Lincoln Home
    • Theses and Dissertations
    • Masters Theses
    • View Item
    •   Research@Lincoln Home
    • Theses and Dissertations
    • Masters Theses
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Effect of nutritional status of dairy cows on the quality of ovarian follicles: an in vitro study

    Gargar, Elbert
    Abstract
    The reproductive efficiency of dairy cattle around the world is declining as greater selection pressure for increased milk production is applied. In addition, nutrition also adversely affects reproductive performance. The purpose of this study was to investigate if the metabolic profile, that is to say, metabolism-associated serum analytes, bore any relation to the in vitro follicle growth and progression of ovarian cortex cultured in the presence of cows sera. Foetal calf serum (FCS) usually at a concentration of 10% in culture medium such as M199, forms the basis of most tissue culture systems including ovarian follicle cultures and has proved suitable for various species. In this study, cow serum (CS), sourced from a large number (17) of differently managed farms and/or animals to provide some variation in metabolic profile was used to replace FCS in the culture media. To date, no studies have been reported using sera other than foetal calf serum or calf serum for the in vitro culture of ovarian tissue. This study has shown that bovine ovarian follicle growth and progression can be supported in vitro by culture medium containing cow serum (CS). Morphologically the ovarian cortex remained viable after being cultured for a 10 day period in medium containing the gonadotropin follicle stimulating hormone (FSH) and supplemented with 10% CS. To assess the degree of follicular growth and progression occuring in vitro, quantitation criteria based on histological classification of follicles as either F0 (primordial follicle- one layer of flattened somatic cells around the oocyte) or F₁ (primary follicle-a single layer of cuboidal granulosa cells around the oocyte) or F₂ (secondary follicle-surrounded by two or more complete layers of cuboidal granulosa cells) and their diameters as measured using image analysis software, were established. Follicles with diameters within diameter limits of 23-32, 41-53 and 55-70µm were classed as F₀, F₁ or F₂ respectively. To confirm if the follicle progression seen morphometrically in vitro was being driven by the genes known to regulate the process in vivo, the expression of Growth Differention Factor-9 (GDF-9) and Bone Morphogenetic Protein-15) (BMP-15) as represented by the relative concentrations of their respective mRNAs was determined by Quantitative Polymerase Chain reaction (qPCR), was assessed. Relative to the reference gene (actin), GDF-9 and BMP-15 were expressed nearly 14x and 6x respectively in cultures demonstrating high follicle growth. In the absence of FSH in the cultures, gene expression levels were not elevated. Follicular growth and progression levels was negatively correlated with plasma concentrations of β-hydroxybutyric acid but not with other metabolic profile analytes or the fertility marker, antimüllerian hormone (AMH). This suggests that in vitro follicular growth in CS is influenced by the physiological/reproductive status of the cow and we conclude that an in vitro culture system is a practical approach for a sensitive follicle growth bioassay to assess the effect of the internal millieu with respect to fertility.... [Show full abstract]
    Keywords
    secondary follicles; primary follicles; primordial follicles; metabolic profile; follicles; serum metabolites; ovarian cortex; in vivo; FSH; qPCR; in vitro; bovine
    Date
    2013
    Type
    Thesis
    Collections
    • Masters Theses [809]
    • Department of Agricultural Sciences [1445]
    Share this

    on Twitter on Facebook on LinkedIn on Reddit on Tumblr by Email

    Thumbnail
    View/Open
    Gargar_MAgSc.pdf
    Metadata
     Expand record

    Related items

    Showing items related by title, author, creator and subject.

    • Factors which affect the fibre output of isolated wool follicles maintained in vitro 

      Winder, Louise Maree (Lincoln University, 1995)
      A technique for growing individual wool follicles in vitro was developed to test the hypothesis that endocrine growth factors are responsible for the regulation of wool growth. Examination of the fibres produced showed ...
    • Analysis of the genetic and phenotypic expression of a variant Romney in the progeny of three breeds of sheep : the Tukidale, a carpet wool mutant 

      Pearse, A. J. T. (Lincoln College, University of Canterbury, 1977)
      In two successive lambing seasons two rams exhibiting double structured carpet-wool type fleeces, well developed horns and heterozygous for the gene T, assumed responsible for this primary pleiotropic phenotype and considered ...
    • A study of seasonal changes in serum levels of reproductive hormones, semen production and libido in stallions located in Canterbury, New Zealand 

      Harris, J. M. (Lincoln College, University of Canterbury, 1980)
      In a preliminary study of seasonal reproductive changes in stallions, four blood samples per week were collected on three separate days from each of four standardbred and two pony stallions for ten consecutive months. Each ...
    This service is managed by Learning, Teaching and Library
    • Archive Policy
    • Copyright and Reuse
    • Deposit Guidelines and FAQ
    • Contact Us
     

     

    Browse

    All of Research@LincolnCommunities & CollectionsTitlesAuthorsKeywordsBy Issue DateThis CollectionTitlesAuthorsKeywordsBy Issue Date

    My Account

    LoginRegister

    Statistics

    View Usage Statistics
    This service is managed by Learning, Teaching and Library
    • Archive Policy
    • Copyright and Reuse
    • Deposit Guidelines and FAQ
    • Contact Us