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The Power of Visual Learning with the Animal Science Image Gallery

by Harold Hafs

            For most students, visual aids usually facilitate transfer of information, especially conceptual information.  Here follows two examples.  To view them, just key in the ASIG number into the search box on the Image Gallery home page.  The video in ASIG #3259 illustrates where and when sperm develop the capacity for motility in the excurrent ducts of the male reproductive tract.  Most of us would be challenged to create this video today!  It is even more impressive because it was a product of novel research by Richard Blandau about half century ago when few people performed video photomicrography. Read more


Sperm Maturation in the Male Reproductive Tract (ASIG #3259)

by Harold Hafs

Sperm Maturation in the Male Reproductive Tract (ASIG #3259) is a 12.5-minute video of the potential for motility of sperm from the various parts of the male reproductive tract.  In this file, Richard Blandau demonstrated that sperm are immotile in the male tract, and remain mostly immotile or abnormally motile even when they are removed from the male tract.  Instead, sperm show normal progressive motility only after ejaculation.  The video illustrates one part of sperm maturation; sperm develop the capacity for motility as they are propelled by fluid flow and peristalsis through the seminiferous tubules, the epididymis, and the ductus deferens. The video contains examples of several types of circular (abnormal) motility, as well as slow motion of normal motility with rotation of the sperm head.

This image, along with other image files such as videos, animations, and sequences of images with a story in Power Point collections or ZIP files as may be found in the Image Gallery.


Spermatogenesis Animation (ASIG #5147)

by Harold Hafs

Spermatogenesis Animation (ASIG #5147) is a 13-minute collection of drawings created mostly by Rupert Amann, and animated/narrated by John Riesen.  It illustrates and describes the location of spermatogenesis within the seminiferous tubules of the testis, in addition to the interstitial tissue where Leydig cells produce testosterone. Animations capture each step of spermatogenesis from the perpetual renewal of spermatogonia stem cells on the basement membrane of the tubules, commitment of spermatogonia to enter spermatogenesis, mitotic division of spermatogonia to form primary spermatocytes, meiotic division to form secondary spermatocytes and spermatids, spermiogenesis wherein the spherical spermatids mature to form spermatozoa, culminating with spermiation. This entire process is nurtured by Sertoli cells that completely envelop the spermatogonia, spermatocytes, and spermatids from the first cell division until the sperm are released into the lumen of the seminiferous tubules, approximately 61 days in bulls. Tight junctions among the Sertoli cells form a basal compartment next to the basement membrane of the tubule with an environment required for the early stages of spermatogenesis, and an adluminal compartment with an environment prerequisite for the later stages of spermatogenesis. When spermatid maturation is complete and spermatozoa are released from Sertoli cells, fluid produced within the tubules transports sperm throughout the length of the tubules and out of the testis into the efferent ducts, converging in the epididymal duct forming the major functional element of the epididymis.  Sperm leaving the seminiferous tubules are infertile. Maturation of sperm occurs in the epididymis where they develop motility as described in ASIG #3259 as well as the capacity to fertilize an egg.

This image, along with other image files such as videos, animations, and sequences of images with a story in Power Point collections or ZIP files as may be found in the Image Gallery.

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Overview of CVM Bioresearch Monitoring Webinar

Join us for a Webinar on Thursday, April 17, 2014. Space is limited.

Register Now

Dr. Vernon Toelle will cover a general description of the Bioresearch Monitoring (BIMO) inspectional compliance programs and the process of how a BIMO assignment in CVM is processed through the Office of Regulatory Affairs and back to the Center.

Title: Overview of CVM Bioresearch Monitoring Date: Thursday, April 17, 2014 Time: 12:00 PM – 1:00 PM CDT

After registering you will receive a confirmation email containing information about joining the Webinar.



System Requirements PC-based attendees Required: Windows® 8, 7, Vista, XP or 2003 Server

Mac®-based attendees Required: Mac OS® X 10.6 or newer

Mobile attendees Required: iPhone®, iPad®, Android™ phone or Android tablet

ASAS announces science writing internship for summer 2014

ASAS_logo1-300x296Company: American Society of Animal Science

Position: Science writing internship

Job description: The American Society of Animal Science is looking for three interns to work for eight weeks this summer (2014). Internship runs from the week of June 9 to the week of Aug. 4. Interns will work with the ASAS Scientific Communications Team to write press releases, write and edit online content, produce podcasts and create video content for ASAS sites. Interns will also travel for one week, expenses paid, to Kansas City, MO to report on the ASAS annual meeting. Read more

Recent Articles


Milk is indeed not just another food

The most recent issue of Animal Frontiers, entitled “Milk – Not Just Another Food” (Vol. 4, No. 2, April 2014), edited by P. Yvan Chouinard of Université Laval and Christiane L. Girard of Agriculture and Agri-Food Canada, enlists an international group of experts to address the controversial issue of the health consequences of increasing human consumption of milk. Read more »

Schematic representation of the different processing steps used in the manufacturing of butter, with their impact on milk matrix structure. (I) Pasteurized cream is churned in order to induce a phase inversion; (II) the milk fat globule membrane (MFGM) is ruptured; (III) the expelled liquid (i.e., sweet buttermilk) resulting from churning is drained, and butter grains are further processed.

Buttermilk: Much more than a source of milk phospholipids

V. Conway, S.F. Gauthier, and Y. Pouliot


  • Resulting from churning of cream, sweet buttermilk is a source of unique bioactive molecules capable of modulating cell signaling, lipid transport, metabolism, and immunity.

  • Several in vitro and in vivo results provide support for the claim of the cholesterol-lowering action of buttermilk components.

  • Clinical evidence now confirms the cardiovascular health benefits of short-term consumption of whole buttermilk, due most likely to its phospholipid content. Read more »

Thinkstock/Wavebreakmedia Ltd

Selenium in milk and human health

Claudia Cobo-Angel, Jeffrey Wichtel, and Alejandro Ceballos-Márquez


  • Selenium in vegetables, milk, and meat is a highly bioavailable source for humans; further, foods that are intentionally Se enriched can significantly enhance the consumption of Se by humans where Se intake would be otherwise suboptimal.

  • Selenium concentration in milk can be easily manipulated by altering Se supply to dairy cows. Transfer in milk of Se from yeast is more efficient than from inorganic sources, such as sodium selenite/selenate. Read more »

Thinkstock/Tom England

The importance of milk as a source of vitamin B12 for human nutrition

J. J. Matte, M. Britten, and C. L. Girard


  • Among animal products, those from ruminants are particularly rich in vitamin B12, which is naturally synthesized by the ruminal microflora and transferred to milk.

  • Concentrations of vitamin B12 in milk vary considerably and are affected by diet.

  • Dairy products retain, in general, a major part of the vitamin B12 naturally present in milk, some processing conditions may even add to the basal level by production of vitamin B12 from propionic bacterium in Swiss-type cheeses. Read more »


Ruminant milk: A source of vitamins in human nutrition

Benoît Graulet


  • Meeting vitamin requirements is still a worldwide public health problem, especially when taking into account chronic suboptimal intakes. In contrast to what is generally believed, a large part of the population remains at risk, and this risk is primarily dependent on eating habits that, in turn, are dependent on age, physiology, season, geographical area, economic or social status, and cultural behavior.

  • Bovine milk contains the 13 known vitamins, and as a common component in the human diet, it makes a significant contribution to the reference intake of adults for several vitamins such as retinol (vitamin A: 11 to 16%), calciferol (vitamin D: 17 to 50%), riboflavin (vitamin B2: 32 to 46%), pantothenic acid (vitamin B5: 17 to 21%), and cobalamin (vitamin B12; 42 to 56%), according to reference values for fresh milk from USDA. Read more »