In order to further characterize oestrogen production and metabolism during bovine pregnancy, free (f) and conjugated (c) estrone (E1), total free and conjugated oestrogens (tfcOe) and total free oestrogens (tfOe) were determined as marker oestrogens in blood plasma respectively in urine and feces of 10 pregnant cows. For the determination of individual oestrogens blood, urine and feces samples of days 240, 200, 160, 100, 60, 30, 10 and 5 prior to parturition were pooled and the free, sulfo (sc)- and glucuconjugated (gc) forms of E1, 17 beta-estradiol (E2 beta) and 17 alpha-estradiol (E2 alpha) were obtained following differential enzyme hydrolysis and separation by HPLC; hormone assay was by established RIA-procedures. FE1 and cE1 concentration in blood plasma, tfOe in feces and tfcOe in urine showed a similar pattern. A first rise occurred between days 110 and 120 of pregnancy, an additional overproportional rise commenced at around days 230-250. Highest concentrations were measured in feces (tfOe ca. 500 ng/g 1 day a. p.), followed by urine (tfcOe ca. 3.5 ng/mosmol 2 days a. p.) and blood plasma (fE1 ca. 8 nmol/l and cE1 ca. 20 nmol/l 2 days a. p.). Determination of individual oestrogens in blood plasma revealed that fE2 beta and fE2 alpha could only be found 10 days a. p. while the conjugated forms could already be detected on days 100 and 160 a. p. With 62% E1 was the dominant oestrogen, followed by E2 alpha (37%) and E2 beta (1.0%); E1 occurred predominantly as sulfate, E2 alpha and E2 beta predominantly as glucuronide. Main metabloite in feces was fE2 alpha (56.7%), followed by fE2 beta (32%) and fE1 (11.3%); conjugated oestrogens were not detected. Main metabolite in urine was scE1 followed by gcE2 alpha and gcE2 beta. ScE2 alpha and scE2 beta were not detected or were present in small quantities only. Hormonal changes over time were highly significant. Main product of placental oestrogen synthesis is scE1, the concentrations of f and c E2 beta and E2 alpha in plasma largely result from oestrogen metabolism and enterohepatic circulation.
We report the results of an ultrastructural study of Triton X-100-extracted, Mg-adenosine triphosphate (ATP)-reactivated bull sperm. We utilized a rapid fixation method to look for differences in the flagellar apparatus that correlate to the state of motility of reactivated sperm models. In a companion article, we examined the motility characteristics induced in bull sperm models by varying the concentration ratio of ATP and Mg(2+) and the stabilizing effect of adenosine diphosphate (ADP) on coordinated beating. Based on the results of that report, we selected four dissimilar states that appeared to represent extremes. One reactivation condition produces vigorous motility similar to live sperm, another produces large amplitude, low frequency beating while the remaining two conditions produce small amplitude vibrations of the flagellum with little coordinated beating. Morphometric analysis of transmission electron micrographs of sperm from these four treatment conditions revealed statistically significant differences between the samples in regard to axoneme diameter, inter-microtubule doublet spacing, and outer dense fiber (ODF) spacing. Our results show that Mg(2+) decreases the axoneme diameter and reduces interdoublet spacing, while ATP, uncomplexed with Mg(2+) , had the opposite effect. We also provide supporting evidence that this may be due to Mg(2+) increasing, and ATP decreasing, the interdoublet adhesion of dynein. We also found that 4 mM ADP significantly increases the separation between the ODFs and the space between the ODFs and the central axoneme within the middle piece. We present a hypothetical explanation that is consistent with our results to explain how ATP, ADP, and Mg(2+) act to regulate the beat cycle. © 2014 Wiley Periodicals, Inc.
ResumoO desenvolvimento de tecnologias capazes de aumentar a eficiência reprodutiva tem crescido nos últimos anos, mas no gênero Leontopithecus existem poucos relatos sobre suas características reprodutivas. A eletroejaculação tem sido empregada com sucesso na colheita de sêmen de animais ameaçados, incluindo primatas não-humanos. O objetivo deste trabalho foi estabelecer um protocolo para a colheita de sêmen em Leontopithecus chrysomelas e verificar as características do sêmen em animais mantidos em cativeiro. Neste estudo foram utilizados dez machos adultos do Centro de Primatologia do Rio de Janeiro (CPRJ-FEEMA). Após a sedação, os animais foram estimulados após a introdução de um transdutor via retal para a eletroejaculação, segundo a técnica descrita por Gould et al. (1978), com algumas modificações. Os sagüis foram submetidos a 10 estímulos de cada voltagem, de forma crescente (2, 3, 4 e 6 Volts), até que se obtivesse o ejaculado. Os primatas ejacularam em média após 29 ± 12,3 estimulações, em uma voltagem média de 4 Volts. Foram obtidos ejaculados em todos os animais, porém, alguns deles (17,5%) não apresentaram ereção peniana. O sêmen obtido apresentou aspecto leitoso, ligeiramente amarelado, consistindo de uma porção que rapidamente coagulava. O volume médio foi de 11,9ml ± 4,73ml e verificou-se uma média de 32,71% de patologia espermática. Das alterações morfológicas do sêmen, as mais comumente observadas foram as patologias de peça intermediária (38,63%), caudas fortemente dobradas (22,4%) e patologia da cabeça dos espermatozóides (16,25%) Os resultados demonstraram que a estimulação transretal pode ser considerada um método seguro e eficiente para colheita de sêmen em Leontopithecus chrysomelas e que amostras de sêmen podem ser colhidas rotineiramente.Palavras-chave: Leontopithecus chrysomelas, primatas, sêmen, eletroejaculação, morfologia espermática. AbstractThe development of technologies capable of improve reproductive efficiency has been increased in last years, but in genus Leontopithecus, there are few reports describing a bout this reproductive characteristics. The electroejaculation has been employed successfully in many endangered animals, including non-human primates. This study intended develop a semen collection protocol for Leontopithecus chrysomelas and verify the semen characteristics of captive the animals. Ten adult males Leontopithecus chrysomelas of Rio de Janeiro State's Primatology Center (CPRJ-FEEMA) were used in this study. After sedation, they had their semen collected by electrical stimulation after introduction of a trans-rectal probe, based on the technique described for GOULD et al (1978), with some modifications. The animals were submitted to 10 stimulus of each voltage of 2, 3, 4 and 6 Volts, until ejaculation that occurred after a mean of 29 ± 12.3 stimulations with mean of 4 Volts. Samples were obtained in all animals but some of them (17.5%) did not demonstrate penile erection. The semen collected had milky aspect, slightly yellow, consisting of one portion that quic...
Comparative study of repeat breeds and healthy mares through endometrial Comparative study of repeat breeds and healthy mares through endometrial Comparative study of repeat breeds and healthy mares through endometrial Comparative study of repeat breeds and healthy mares through endometrial Comparative study of repeat breeds and healthy mares through endometrial histology and plasmatic progesterone concentrations histology and plasmatic progesterone concentrations histology and plasmatic progesterone concentrations histology and plasmatic progesterone concentrations histology and plasmatic progesterone concentrations.] Estudo comparativo de éguas repetidoras ou não de cio através da avaliação histológica do endométrio e das concentrações plasmáticas de progesterona. Pesquisa Veterinária Brasileira 27 (12) The study aimed to compare endometrial histology and plasmatic progesterone (P4) concentration of repeat breeds and healthy mares. The hypothesis was that there is a correlation between infertility and endometrial histology and P4 concentration in both groups. A total of 36 Campolina and Mangalarga Marchador mares in reproductive age (3-23 years) were used, 11 of them were healthy mares (Control group, 7 embryo recipient and 4 embryo donors), and 25 repeat breeders (10 embryo recipient and 15 embryo donors), classified as based on their reproductive history. Endometrial and blood samples were collected for respectively histological and plasma progesterone concentration evaluation. The endometrial samples obtained after biopsy were fixed in Bouin's fluid, processed, included in paraffin, and stained with HematoxylinEosin (HE) for histopathological examination. Plasmatic progesterone concentrations were evaluated by enzyme immunoessay (ELISA). There was no correlation between progesterone concentration and fertility. But there was a positive correlation between age and fertility, as older mares had major tendency of subfertility than younger ones. There was also a correlation between biopsy categories and fertility, as more histological alterations were found, higher were the chances for the mares to be subfertile. However not all mares classified as Category I and II maintained pregnancy until parturition. Other factors could influence pregnancy maintenance. In the same way, not all mares in Category III were infertile. The endometrial biopsy was shown to be an easy and cheap diagnostic technique with minimal discomfort to the animals and, together with other data, to be a very important component in the investigation of mare fertility.
Efeito de diferentes meios de cultivo no desenvolvimento e proporção do sexo de embriões bovinos produzidos in vitro
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