Introduction
A lot of attention is directed towards the female’s side of reproduction. If human couples can’t conceive children, most people think, “What is wrong with her?” Little do they know, there are a lot of potential fertility problems on the male side as well. The Centers for Disease Control and Prevention (2013) conducted a national study in 2002 with data showing that approximately 11% of 15 – 44 year old women in the U.S. have some sort of pregnancy difficulties. That same report also shows that 7.5% of men under the age of 45 have fertility problems as well.
That statistic of males having a role in low conception rates is also true for cattle. For both beef and dairy producers alike, it is essential to study the male side to increase fertilization rates in your herd. Chenoweth (2005) states that the purpose of the bull is to provide the female cow with attainable spermatozoa and to successfully deliver them into the vagina during copulation to fertilize the ova. But, what happens if the bull is unable to? Beef producers don’t want to cull an expensive bull. Some questions that the producer might think are: “Is this defect heritable? What caused the bull to be infertile? Is this a long term effect? Will it go away after a period of time?” All of these questions can be answered with the ever changing reproduction knowledge that animal scientists are receiving.
Physical Scrotum Infertile Conditions
The testis of the bull are a very important organ to study when one talks about fertility among males. It has been said that there is a positive correlation between scrotum size and number of fertile sperm. It’s known that with increase in age of the bull you have an increase in scrotal circumference, yielding h...
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America is one of the world’s largest producers of beef. According to Raloff (2002), approximately 36 million beef cattle are raised in America each year, and approximately two-thirds are treated with hormones (para.2). Farmers use these hormones to increase the rate of growth in their cattle. By increasing the cattle’s growth rate, the farmers can produce more beef and still making more money, they can sell it at an inexpensive rate to the consumers. The hormones that may be administered to beef and dairy cattle may already be produced, in small amounts, naturally in their own bodies or synthetic. According to the U.S. Department of Food and Drug Administration (2002), “the accepted naturally occurring hormones that may be administered to beef and milk producing cattle are estradiol, progesterone, testosterone, and the synthetic hormones that are accepted are zeranol, trenbolone acetate, and melengestrol acetate.” None of the hormones listed above are acceptable in the industries in Europe to give for the food and milk productions.
For many years, infertile couples have had difficulty facing the reality that they can not have children. According to Nidus Information Services Incorporated, 6.2 million women in the United States are infertile. This problem leads to many options. A few options have been used for a long period of time: the couple could adopt a child or keep trying to have a child themselves. For those couples that want to have their own children, there are new options arising. In vetro fertilization is an option that gives couples the chance to have a doctor combine the male's sperm and the woman's eggs in a petri dish and implant them into the woman's womb after the artificial conception. This may result in multiple pregnancies - more than five in some cases. This does not only occur in implantation, however. Many times the patient's doctor will ask her to consider selective reduction: aborting a few fetuses to save the ones she can. In a case of multiple pregnancy, selective reduction should be considered an option.
opportunities in reproductive technology, “one thing that’s not been well defined is what really constitutes research and what is [merely] improvement in clinical design,” Dr. Strom said. (Foubister) Sperm retrieval, in which an elec...
An attempt by Dr. Nnaemeka Amobi and his team at producing a male contraceptive pill involves the idea of a hormone-free pill that can decrease or eliminate the emission of semen. The idea is to relax the muscles that propel semen so that...
The testes produce sperm and sex hormones, testosterone. Surrounding each testis is a coiled tube called the epididymis, which collects and stores sperm, very much similar to that of a human. Before ejaculation a seminal fluid is added by the seminal vesicles, to prevent the sperm from drying out.
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According to the Centers for Disease Control and Prevention, 2.1 million married couples experience troubles with infertility. Infertility is defined as trying for over a year and not becoming pregnant for women under 35 and trying for six months for women over 35. The cause of the infertility is a male factor one third of the instances, female another third, ten percent of the cause is a combination of both male and female factors and the remaining twenty percent is not apparent. In vitro fertilization is a process that tries to eliminate the problems inherent in the mother and father. It involves an egg is fer...
“Managing Infertility.” USNews.com. Stanford University Medical Center, 31 Mar. 2007. Web. 22 Mar. 2010. .
For the purposes of this research, the focus will be on infertility among women of childbearing
The male reproductive system is a set of organs that works together to produce sperm which will later in life fertilize females eggs. The testes are the most important part of the system because it produces sperm cells. It is similar and looks similar to ovaries of a female’s reproductive system because it also holds what they need to reproduce. Its job is to produce the sperm cells needed to reproduce. Due to hormonal imbalances the production of sperm cells may not even be possible in some males. Testosterone is the male the hormone that gives men there manly characteristics. It is made up of hydrogen, carbon, and oxygen with a white color. In the male body it helps develop sex organs, a deeper voice, and facial hair (Khalid, 2013). Cancer or a genetic disorder in males is the most common thing that cause the reductions of testosterone production in the body. Behind the testes is the epididymis which lets sperm go through the vas deferens from the testes (Dictionary, 2014). It looks like leach the way it is position right on the testes but it is thinner. When sperm is produces the ...
Most people believe it takes a strong sperm to make it through to the egg. I will be honest this is what I believed too until I watched this video. In fact, I am pretty sure I have even heard it called the “winning sperm.” Going against the popular belief, it is actually the women that decides when the sperm and egg will come together. One teaspoon of male ejaculation contains 300 million sperm, but the vagina is acidic making it impossible for all of them to survive. Success by a single sperm is determined by the women and only during a couple days of every month. I liked this part of the video because I could not help but to think “Yeah girl power!” Anyways, women are able to control when the sperm is successful through the process of ovulation. Ovulation clears out some of the mucus in the vagina which allows it to guide the sperm through to the egg. Even with this assistance, it ends up being a two day swim for the sperm. One thing the video taught me about this is that the fastest sperm is not necessarily the one that gets fertilized with the egg because it sometimes gets there too fast and the egg is not ready yet. This is another misconception I had heard about as well. I always thought the “winning sperm” was the fastest sperm. This video explained this well by telling the audience that the fastest sperm sometimes beats the egg and so it cannot
In 1939, the first IVF was conducted on rabbits, hamsters, and mice; however, IVF was seen as impossible on a human and was regarded with incredulity into scientific and medical practices across the country. In 1978, the world witnessed the birth of the first “test tube baby,” Louise Brown (Zhao, Brezina, Hsu, Garcia, and Wallch, 2011).