نتایج جستجو برای: sperm head vacuole

تعداد نتایج: 213756  

Journal: :Theriogenology 2011
L du Plessis J T Soley

The accurate assessment of avian sperm abnormalities is hampered by a lack of descriptive data and by the confusing terminology currently in use. Critical appraisal of semen samples from the distal ductus deferens of the emu revealed that two closely related yet separate (distinct) defects previously collectively referred to as "bent sperm" or "crooked-necked sperm" could be identified by light...

Journal: :Human reproduction 2010
L Maree S S du Plessis R Menkveld G van der Horst

BACKGROUND Assessment of sperm morphology (including morphometry) is extensively used to determine one of the qualities of a semen sample and depends on the differential staining of spermatozoa. A staining technique should cause as little change to sperm dimensions and form as possible in order to reliably evaluate the morphometric features of the sperm. Various staining techniques have been em...

2010
Davendra Kumar Anil Joshi S. M. K. Naqvi

The present study was conducted to compare sperm motion characteristics of adult Malpura and Bharat Merino rams by the computer-aided sperm analysis (CASA) technique. Malpura is a hardy native sheep breed of the semi-arid tropical environment and Bharat Merino is a crossbred evolved in the same environment by crossing native sheep with exotic rams. Semen was collected from 8 donor rams of each ...

Journal: :Prague medical report 2013
S Singh L Das Roy S Giri

Metronidazole (MTZ) is a common antiparasitic and antibacterial drug. The drug and X-ray induced effects in mouse sperm count, sperm head abnormality and some oxidative stress parameters have been studied. Simultaneously the protective role of curcumin has been evaluated. MTZ, 40 mg/kg bw and 13.4 mg/kg bw × 3 days exposure induced abnormal sperm head and reduced total sperm count in Swiss albi...

2016
Alejandro Maroto-Morales Olga García-Álvarez Manuel Ramón Felipe Martínez-Pastor M Rocío Fernández-Santos A Josefa Soler José Julián Garde

The spermatozoon is the most diverse cell type known and this diversity is considered to reflect differences in sperm function. How the diversity in sperm morphology arose during speciation and what role the different specializations play in sperm function, however, remain incompletely characterized. This work reviews the hypotheses proposed to explain sperm morphological evolution, with a focu...

Journal: :Developmental biology 2016
Raymond C Pasek Erik Malarkey Nicolas F Berbari Neeraj Sharma Robert A Kesterson Laura L Tres Abraham L Kierszenbaum Bradley K Yoder

Spermiogenesis is the differentiation of spermatids into motile sperm consisting of a head and a tail. The head harbors a condensed elongated nucleus partially covered by the acrosome-acroplaxome complex. Defects in the acrosome-acroplaxome complex are associated with abnormalities in sperm head shaping. The head-tail coupling apparatus (HTCA), a complex structure consisting of two cylindrical ...

2014
Julia Fuller Roger Goodwill

• General sperm shape characterized by conical head • Eggs characterized as large spheres in vitelline membrane • Atlantic and Pacific populations’ spermatozoa show major morphological differences from each other (Landry et al. 2003) • Western Pacific species’ sperm head length measured twice that of Central Pacific (Marks et al. 2008). • Deep sea sperm head length elongated compared to shallow...

2013
María Varea Sánchez Markus Bastir Eduardo R. S. Roldan

Mammalian spermatozoa, particularly those of rodent species, are extremely complex cells and differ greatly in form and dimensions. Thus, characterization of sperm size and, particularly, sperm shape represents a major challenge. No consensus exists on a method to objectively assess size and shape of spermatozoa. In this study we apply the principles of geometric morphometrics to analyze rodent...

2016
Jesús L Yániz Sara Capistrós Sandra Vicente-Fiel Carlos O Hidalgo Pilar Santolaria

The aim of this study was to compare the sperm nuclear and acrosomal morphometry of three species of domestic artiodactyls; cattle (Bos taurus), sheep (Ovis aries), and pigs (Sus scrofa). Semen smears of twenty ejaculates from each species were fixed and labeled with a propidium iodide-Pisum sativum agglutinin (PI/PSA) combination. Digital images of the sperm nucleus, acrosome, and whole sperm ...

Journal: :Theriogenology 2005
Peter J Chenoweth

Genetic sperm defects are specific sperm defects, which have been shown to have a genetic mode of transmission. Such genetic linkage, either direct or indirect, has been associated with a number of sperm defects in different species, with this number increasing with improved diagnostic capabilities. A number of sperm defects, which have proven or suspected genetic modes of transmission are disc...

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