Bài giảng tiếng anh chuyên ngành chăn nuôi thú y

THAI NGUYEN UNIVERSITY OF AGRICULTURE AND FORESTRY Thai Nguyen University of Agriculture and Forestry TUAF, as a member of the Thai Nguyen University, was established in 1970 with the n

Lesson 1

THAI NGUYEN UNIVERSITY OF AGRICULTURE AND FORESTRY

Thai Nguyen University of Agriculture and Forestry (TUAF), as a member of the Thai Nguyen University, was established in 1970 with the name of Thai Nguyen College of Agricultural Technology In 1972, under the decision No 750/VP/15 of the Prime Minister of Vietnam, its name was changed into BacThai University of Agriculture No III Since 1994, under decision No 31/CP its name has become Thai Nguyen University of Agriculture and Forestry

Thai Nguyen University of Agriculture and Forestry is an educational and research institute for agriculture, forestry, environment and resources technology and management The goal of the University is to provide highly-educated manpower, research and technology in fields of agriculture, rural development, environment and resources management for sustainable development of Vietnam, especially the North Mountainous Region of Vietnam

Through nearly four decades of development, TUAF has been experiencing growth in qualitative and quantitative aspects The University has been recognized as one of leading national agricultural universities in Vietnam As a result, the University has been granted some noble awards from the Vietnamese Communist Party and the Government such as the Third Class Labor Medal, the Second Class and the First Class Medals in 1990, 1995 and 2000 respectively For these achievements, the University was given the Third Class Independence Medal in 2005 This is a good honor fully deserved by all the University staff and students Thus, the University staff and students are working hard to develop the Thai Nguyen University of Agriculture and Forestry to become a leading Center in education, training and technical transfer in the area of Agriculture, forestry, environment and resource management towards industrialization and modernization

In pursuit of excellence in education, researches and public services, TUAF is continuously attempting to improve the quality of education and research programs to meet the demand of global integration and market oriented labor demands Diversifying education and training programs, improving training curricula and teaching methods and upgrading research facilities have been recognized as the key issues for the development of the University in the 21st century The development of

international cooperation is being promoted to improve the capacity of the University staff, training program and curricula, and research facilities

As the mission and foundation of TUAF, we will be continuing our tradition of excellence in research and education We hope that you will join us to make a prospective future for NMR and Vietnam

The main goal of Thai Nguyen University of Agriculture and Forestry is to provide highly qualified staff and researchers in the area of agriculture and forestry and technical and management for Northern mountainous provinces of Vietnam Since its establishment, the University has continuously developed and became the leading Center of education and training in the region At the beginning, the University provided training only for bachelor degrees of Agronomy and Animal Husbandry Today, the University provides training for different degree levels such as Doctor of Philosophy (Ph.D.), Master's, Bachelor, and Diploma with 17 different training areas After 35 years, the University has completed 2 PhD, 4 Master's, 16 Bachelor and many Diploma courses with the total graduates of 12,966 Bachelors,

232 Master's and PhDs

Since year 2000, the University has implemented four (4) national-level research projects, 137 ministry-level research projects and 323 university-level research projects, 48 projects with government organizations and international non-government organizations, and 106 projects of technical transfer in the region The University has close relationship with all Northern provinces, and relevant ministries

in the areas of agriculture, education and training, aquaculture and rural development

In the context of global integration, the University has successfully established relationship with many universities, institutions and organizations in the world from Germany, Canada, United States of America, Thailand, Korea, Australia, Netherlands, China, Japan, and other countries in order to improve the quality of education, research and training through cooperation and exchange activities The University has always paid high attention to the development of staff in quantity and quality as well

as planning for well-balanced teaching and service staff The teaching staff is 268, one (1) of which is a Professor, 16 are Associate professors, 52 are Doctors, the remaining are Master's degree holders and some teaching assistants have Bachelor degrees About 30% of teaching staff can communicate in English in their work and

more than 8000 The full time students were more than 4000 and graduate students were 198

In order to meet the requirements for industrialization and modernization of the agriculture sector, the University has developed a comprehensive development strategy in the mobilization and effective use of resources to make an innovative change in training programs and teaching methods, and ensure the adequate quantity and quality of staff for successful completion of key training and technical transfer programs such as biotechnology, post harvest and processing technology, resource management, and others

The Thai Nguyen University of Agriculture and Forestry has always

successfully completed the tasks given by the State and Government The University's party committee has been recognized by Thai Nguyen provincial committee Party as a good and strong party committee for many years

Lesson 2

GENERAL INTRODUCTION ABOUT THE FACULTY OF

ANIMAL HUSBANDRY AND VERERINARY MEDICINE

I Reading comprehension:

The Faculty of Animal Husbandry and Veterinary Medicine was established in

1970 It was amongst 6 academic departments in Bac Thai University of Agriculture and Forestry at that time Its mission is to Train, research and technology transfer in fields of animal sciences and veterinary medicine, and aquaculture The Faculty of Animal science and veterinary medicine has had 38 years experience in training, research, extension and integration activities It has recruited a major number of competent veterinarians and agricultural engineers who have enthusiastically contributed to the health and well- being of animals as well as humans in the northern part of Vietnam

The Faculty of Animal science and Veterinary Medicine consist of 6 academic departments included:

1 Animal Physiology and Biochemistry

2 Animal Genetics – Breeding - Feed

3 Animal husbandry science

4 Infectious Pathology

5 Veterinary Pharmacology

6 Valuable and Rare Animal Husbandry - Aquaculture

The educational service facilities are:

- Practical laboratories in each department use for subject practical lessons

- 01 Central laboratory

- Centre for agriculture experiment and practices

About human resource: The Faculty of Animal Husbandry and Veterinary Medicine has 47 staff members, in which there is one professor, 6 associate professors, 25 senior lecturers holding Ph.D and MSc degrees, 14 teaching assistants, 2 Technicians and 989 full – time students

II Vocabulary

1 Husbandry: ['h zbəndri] : Công việc chăn nuôi, nghề chăn nuôi

3 Veterinarian: [,vetəri'neəriən]: Bác sĩ thú y

5 Establish: [is'tæbli∫]: Lập, thành lập, thiết lập, kiến lập

6 Agriculture: ['ægrik lt∫ə]: Nông nghiệp

7 Forestry: ['f ristri]: Khoa học và công việc trồng, quản lý rừng; lâm nghiệp

10 Theoretical: [,θiə'retikl]:(thuộc): Lý thuyết; có tính chất lý thuyết

11 Practical: ['præktikl]: Thực hành (đối với lý thuyết

12 Prevention: [pri'ven∫n]: Sự ngăn ngừa, sự ngăn trở

13 Diagnosis: [,daiəg'nousis]: (y học) phép chẩn đoán; sự chẩn đoán

14 Treatment : ['tri:tmənt]: Sự đối xử, sự đối đãi, sự cư xử (với người nào)

17 Aquaculture: [,ækwə'k lt∫ə]: Nghề nuôi trồng thuỷ sản

23 Create: [kri:'eit]: Tạo, tạo nên, tạo ra, tạo thành, sáng tạo

25 Cattle: ['kætl] : Loại động vật có sừng và móng chẻ như bò, nuôi để lây sữa hoặc ăn thịt; gia súc

26 Biochemistry: [,baiou'kemistri]: Khoa hoá sinh

27 Pharmacology: [,f :mə'k lədʒi]: Khoa dược lý (nghiên cứu tác dụng của thuốc lên cơ thể)

28 Infrastructure: [,infrə'str kt∫ə]: Các bộ phận, thiết bị phụ thuộc, tạo thành cơ

sở của một hệ thống, cơ sở hạ tầng

29 Laboratory: [lə'b rətəri]: Phòng thí nghiệm; phòng pha chế

30 Experiment: [iks'periment]: Thực nghiệm

31 Analysis: [ə'næləsis]: Sự phân tích; phép phân tích

33 Culture: ['k lt∫ə]: Sự cấy (vi khuẩn); số lượng vi khuẩn cấy; mẻ cấy vi khuẩn

34 Microorganism: [,maikrou' :gənizm]: Sinh vật nhỏ đến nỗi chỉ thấy được qua kính hiển vi; vi sinh vật

35 Senior: ['si:niə]: Nhiều tuổi hơn; cao hơn về cấp bậc hoặc chức quyền ; lâu năm hơn, thâm niên hơn

36 Lecturers: ['lekt∫ərə]: Giảng viên đại học

III Exercise

Practice 1: Answer the following questions

1 When was the Faculty of Animal Husbandry and Veterinary Medicine established?

………

………

2 What are the missions of the Faculty of Animal Husbandry and Veterinary Medicine?

1 From all above possible information, write a short message about FASVM

(preferably 50 words) to summarize what you have learned from the passage

Animal Breeding, Genetics & Genomics: Animal protein is essential in

meeting escalating nutritional needs around the world Animal Breeding, Genetics & Genomics research focuses on desirable genetic animal traits that have revolutionized poultry, livestock, and fish production These genetic traits include animals that are leaner; have increased disease resistance; or excel in growth rate or the production of eggs, meat, milk, wool, or mohair The natural efficiency of an animal to use

nutrients in its feed could affect the nutrients in the manure and thus affect the environment

Animal Nutrition and Growth: Inefficient nutrient intake by animals is

financially and environmentally costly in animal operations from livestock farms to fish farms It not only hurts animal growth, health, and well-being, but it may also affect the safety and quality of the food products It may result in excess nutrients polluting the environment in the form of odors or ground water contamination The primary objective of the Animal Growth and Nutrition Program is to discover the nutritional, biological, and genetic factors underlying:

• Normal animal growth

• Nutrient digestion and efficiency

• Metabolism

• Lactation

• Muscle and bone development

Animal Products: Americans buy approximately $100 billion of animal products

at the farm gate, and several times that amount at retail each year These products include meat and meat products, poultry products (meat and eggs), fish, shellfish, dairy products (milk and cheese), and non-food products such as fiber (wool, mohair, cashmere, and leather)

The quality and safety of animal products prior to harvest are influenced by genetics, nutrition, and management systems After harvest they are affected by handling, processing, storage, and marketing practices

Animal Reproduction: Reproductive efficiency is the major factor affecting

profitability in many livestock production systems For example, the fertility of domestic ruminants (cattle and sheep), even under optimal conditions, is only about

50 percent Inefficient reproduction may be caused by numerous factors, including:

• Increased genetic selection for meat or milk production traits

• Early embryonic and fetal loss

• Failure to reach puberty at an optimum age or an inability of young females to conceive early in the breeding season

• Environmental stressors such as temperature extremes or changes in photoperiod (day and night cycle)

• Production of sperm with a low potential for fertilization

• Limited sex drive

Animal Well-being: Evaluating farm animal well-being is a challenge to the

animal food industry and scientific communities Scientists study how to accurately measure an animal’s state of comfort and well-being For example, scientists study animals in different environmental conditions that vary in temperature, humidity, amount of daylight, bedding, size and shape of living quarters, and the number of other animals in the environment They also work to understand how animals react both behaviorally and biologically in stressful situations, such as in transport, or when animals must be restrained, such as during a medical evaluation or treatment These understandings are important to those who work with animals as pets, livestock, or wildlife to ensure the safety and well-being of both animals and humans as they interact

8 Biological (adj) [ ]: Sinh vật học

19 Wildlife: Thú vật, chim muông hoang dã

30 Pet (n) [ ]: Thú cảnh

III Exercise

Practice 1: Answer the following question:

1 What challenges do researchers and educationist confront with in order to optimize animal production?

8 What could be the causative factors accounted for the inefficient reproduction?

Practice 2: True or false statement:

1 Research, education and extension activities did not change to address new

2 Researchers collaborate with industry and other interested parties to develop and disseminate knowledge and methods to improve agriculturally relevant animal

3 The quality and safety of animal products prior to harvest do not depend on genetics, nutrition, and management systems TRUE FALSE

4 Inefficient nutrient intake by animals does not affect environment in animal operations from livestock farms to fish farms TRUE FALSE

Practice 3: Word/phrase usage

Fill in the blank the most appropriate word or phrase

1 One of the most important tasks for the extensionist is to …… Knowledge to the farmers

A, Disseminate B, Talk C, Tell D, Get E, Obtain

2 Beside dogs and cats, some wild animals e.g snakes, croccodie etc are also considered as …

A, Friendly B, Pets C, Aggressive D, Submissive

3 A Hostein Frisian cow can produce up to 8000 kg of milk in one …… period

A, Photoperiod B, Cycle C, Course D, Latation

4 High producing cows have a high requirement for energy supplied by …… that differ in nature

A, Nutrients B, Water C, Clay D, Vegetable

Lesson 4

ANIMAL PHYSIOLOGY

Source: Knut Schmidt Nielsen Animal Physiology – Adaptation and Environment 5th Edition Cambridge University Press

OVERVIEW OF ORGAN SYSTEMS OF THE ANIMAL BODY

Organ Major component organs Function

Integument Skin, nails, and hair; cutaneous * Protects deeper organs from injury due

Sense organs and glands to bumps, chemicals,

bacteria, and

Dehydration (drying out)

* Excretes salts and urea

* Help regulate body temperature

Skeletal Bones, cartilages, tendons, * Supports and protects internal

organ Ligaments, and joints * Provides levers for muscular action

* Stores minerals (calcium and others)

* Cavities provides a site for blood cell

organs” of the body

* Plays a role in regulation of long –term

homeostasis

Cardiovascular Heart, blood vessels, and blood * Primarily a transport system that carries

blood containing oxygen, carbon dioxide

Propel nutrients, wastes, ions, hormones, and

other substances to and from the cells

where exchanges are made; pumping

action of the heart propels blood through

The blood vessels

*Protects body with blood clots, antibodies,

and other protein molecules in the blood

Lymphatic/ Lymphatic vessels,, lymph nodes * Picks up fluid leaked from the blood

Immune spleen, thymus, and tonsils vessels and returns it to the blood

* Cleanses blood of pathogens and other

small and large intestines, particles which can be absorbed

gallbladder, and pancreas) feces

Urinary Kidneys, ureters, urinary * Rids the body of containing

bladder, and urethra wastes (urea, uric acid, and ammonia),

which result from the breakdown

of proteins and nucleic acids by the body,s

Female: Ovaries, uterine tubes, * Produces germ cells (eggs); the female

uterus, and vagina uterus houses a developing fetus until birth

II Vocabulary

5 Endocrine [ ](n) Tuyến nội tiết, thuộc về nội tiết

6 Carvadiovascular (Thuộc về) tim mạch

8 Immune [ ](n) Miễn dịch

12 Reproductive [ ](adj) Sinh sản, tái sản xuất

13 Cutaneous sense organ and glands Cơ quan nhận cảm và tuyến trên da

20 Special sense organs Tổ chức nhận cảm đặc biệt

39 Small and large intestine Ruột non và ruột già

61 Homeostasis Nội môi, tính cân bằng tự nhiên

67 Debris Mảnh vỡ, mảnh vụn, chất lạ (vào cơ thể)

70 Undigested Không tieu hoá, không hấp thụ

III Exercise

Practice 1 Answer the following questions

1 What is the main function of the skin?

How do animals react to the invasion of foreign substances (e.g pathogen)?

What is the function of the skeletal system?

What is the main difference between blood in the vein and blood in the artery? How do the ingested feeds travel in the digestive system?

Which part of the intestine the digestion and absorption processes are mostly taken place?

2 How does protease break down the protein structure?

3 What is the name of hormone secreted by the adrenal?

What are the most important factors that make the cows come into heat?

10 How do we detect the cow if she comes on heat?

IV Assignment

- Learn all the given keywords and vocabularies

- Make sentences with the given keywords and vocabularies

The nutrition compositions include energy, protein and amino acids, vitamin, minerals, and water Energy plays an important part of animal nutrition Estimates of energy intakes of animal are expressed as kilocalories (kcal) or mega-calories (Mcal)

of digestible energy (DE) or of metabolizable energy (ME) per kilogram of feed and animal per day Digestible energy is dietary gross energy intake minus the gross energy of the excreted feces Metabolizable energy is the gross energy of the diet minus fecal, gaseous, and urinary gross energy Net energy (NE) is the difference between the metabolizable energy and heat increment (HI) The heat increment is the amount of heat released because of the energy costs of the digestive and metabolic processes It has been demonstrated that net energy, although difficult to measure, is the best measure of the energy available to an animal for maintenance and production

Protein generally refers to crude protein, which is defined for feedstuffs as the nitrogen content x 6.25 This definition is based on the assumption that the nitrogen content is 16 grams of nitrogen per 100 g of protein The capacity of the diets to provide sufficient indispensable (essential) amino acids and nitrogen for synthesis of dispensable (nonessential) amino acids determines the adequacy of a dietary protein level Although dispensable amino acids are needed for normal metabolism, dietary

sources are not usually required They can be obtained from feeds or are synthesized

by using amino groups derived from amino acids present in excess of the requirement

The term vitamin describes an organic compound distinct from amino acids, carbohydrate, and lipids that is required in minute amounts for normal growth and reproduction Some vitamins are not required in diets because they can be synthesized readily from other food or metabolic constituents, or by microorganisms

in the intestinal tract Vitamins are generally classified as either fat soluble or water soluble The fat - soluble vitamins include vitamins A, D, E, and K The water – soluble vitamins include the B vitamins (biotin, cholin, folacin, niacin, pantothenic acid, riboflavin, thiamin, B6, and B12) and ascorbic acid

Water account for as much as 82 percent of empty body weight (whole body weight less gastrointestinal tract contents) in the 1.5 kg neonatal pig and declines to

53 percent in the 9 kg market hog Many variable factors, including environmental ones, govern the water requirement of animal Animal obtain water from three sources: (1) water that is consumed; (2) water that is a component of feedstuffs; and (3) water that originates from the breakdown of carbohydrate, fat, and protein (metabolic water) Water is lost from the body by four routes: (1) the lungs (respiration); (2) the skin (evaporation), (3) the intestines (defecation), and (4) the kidneys (urination)

Animal feeding practices have developed over time, and have generally been validated by their use The pace of development has quickened markedly over the past 150 years - in particular, the intensification of the livestock industry in the second half of the 20th century means that a much wider variety of ingredients is used in feed than previously This includes ingredients that might not be thought part

of an animal's natural diet, such as fishmeal Concerns about the recycling of animal material into feed (a practice common in developed countries for many decades) have led, during the past ten to 15 years, to a number of prohibitions on what may be used

in feed The use of mammalian meat and bone meal (MBM) was banned because it was thought to have caused or spread mad-cow disease (Bovine spongiform

encephalopathy, BSE); the ban was subsequently extended to almost all forms of

processed animal protein (PAP) However, there is no positive, restricted list of what may be fed to farmed livestock This is partly because of the likely length of such a list, which could run to hundreds of items, and partly because research into animal nutrition is continually revealing new uses for potential crops Research also continues into the genetic modification of crops used for feed Farmers' choices of what to feed their livestock will be governed by many different factors - the age and species of the animals concerned, their intended products (meat, milk or eggs), the price and availability of feed materials, their nutritive value, and even the time of year and the geographical location (soil type and climate) of the farm The energy and nutrients that feed provides occur in different proportions in different materials, and for many animals a typical diet will consist of a combination of feeds to provide everything they need for their health, welfare and production Ruminants (cattle, sheep and goats) are an exception to this because grass may be the only ingredient in their diet for much of the year

II Vocabulary

1 Nutrition [ ] (n) Dinh dưỡng

2 Implication [ ] (n) Sự liên quan, (Số nhiều) Sự quan hệ mật thiết

3 Composition [ ] (n) Thành phần

4 Requirement [ ] (n) Nhu cầu, sự đòi hỏi

5 Formulation [ ] (n) Sự làm thành công thức, xây dựng công thức

7 Maintenance [ ] (n) Sự duy trì

8 Growth [ ] (n) Sự sinh trưởng, phát triển

9 Digestible energy [ ] [ ] Năng lượng tiêu hoá

10 Metabolic [ ] (adj) Thuộc trao đổi chất

11 Metabolizable energy Năng lượng trao đổi

12 Gross energy [ ] (n) Năng lượng thô

14 Feed [ ] (n) Sự cho ăn, thức ăn gia súc

15 Net energy [ ] (n) Năng lượng thuần

16 Crude protein [ ] [ ] (n) Protein thô (Protein tổng số)

17 Assumption [ ] (n) Sự thừa nhận, sự cho là đúng

18 Indispensable [ ] (adj) Sự cần thiết

19 Dispensable [ ] (adj) Sự không cần thiết

20 Distinct [ ] (adj) Sự khác biệt, riêng biệt

21 Metabolic constituents [ ] (n) Thành phần, phần tử cấu tạo

22 Fat soluble [ ] [ ] (adj) Hoà tan trong mỡ

23 Water soluble Hoà tan trong nước

25 Respiration [ ] (n) Sự hô hấp

26 Evaporation [ ] (n) Sự làm bay hơi, bốc hơi

27 Defecation [ ] (n) Sự đi ỉa, sự gạn, lọc, làm trong,

28 Urination [ ] (n) Sự đi đái, đi tiểu

29 Validate [ ] (n) Làm cho có hiệu lực, hợp lệ

30 Ingredient [ ] (n) Thành phần

32 Prohibitions [ ] (n) Sự ngăn cấm, sự cấm

33 Mammalian [ ] (adj) Thuộc động vật có vú, loài thú

35 Processed animal protein (PAP) Protein có động vật chế biến

36 Genetic modification Biến đổi di truyền

37 Feed materials Nguyên liệu thức ăn

38 Nutritive value Giá trị dinh dưỡng

III Exercise

Practice 1: Working with detail

First read each of the statement in this text Then decide whether each one is true or false according to the reading Circle TRUE or FALSE

1 To achieve more efficient animal production, we must provide in amounts necessary of nutrition to meet the animal’s requirements TRUE FALSE

2 The net energy, although easy to measure, is the best measure of the energy available to an animal for maintenance and production TRUE FALSE

3 The dispensable amino acids can’t be obtained from feeds TRUE FALSE

4 Many variable factors, including environmental ones, govern the water

5 The use of mammalian meat and bone meal (MBM) was banned due to the

Practice 2: Checking Your Understanding

Read each question carefully and then answer the question:

1 What are nutrition compositions in the livestock feedstuffs?

How can we define crude protein?

Why some vitamins are not required in diets?

How much is water amount in empty body weight in the 1.5 kg neonatal piglet?

Why a typical diet of the ruminants will not consist of a combination of feeds?

Practice 3: Building Vocabulary

Practice with words and learn more about them Choose the best word or words to complete a sentence The words in bold type will have you

1 Amino acids, fatty acids, minerals, vitamins, and water are the substances in

the feedstuffs These are necessary for animal growth

A, Nutrition B, Compositions C, Growth

2 The term vitamin describes an organic compound distinct from amino acids,

carbohydrate, and lipids This is required in minute amounts for normal growth and reproduction

A, Difference B, Similar to C, Disproportion

Practice 4: Finding the Main Ideas

1 The main idea of paragraph 1:

a The important of animal nutrition

b The need of formulation of balanced diets

c The role of feed to the animal health

2 The main idea of paragraph 2

a Clarification of the energy role to the animal growth

b Classification of the energy of animal feeds

c How to measure the net energy in animal feeds

3 The main idea of paragraph 3

a The definition of protein and classification of amino acids

b The protein digestion in digestive tract

c The synthesis of protein in the animal organs

4 The main idea of paragraph 4

a Drinking water for livestock

b Water in animal husbandry

c The animal farms should establish the water system for their animals

5 The main idea of paragraph 5

a The use of materials in animal feed production

b The risk of using processed animal products as animal feeds

c The grass production for cows

IV Assignment

1 Uses all possible information above to write a short text (preferably 50 words)

to summarize what your perception about general animal nutrition

It is advantageous in a constant environment because a large number of offspring can

be produced in a short time

Examples:

Flatworms can divide into 2 halves; each half grows into a separate organism

Cnidarians undergo budding where a new individual grows from and then breaks off

of the parent individual

Echinoderms can be cut to form new individuals

Insects- parthenogenesis (unfertilized egg develops)

Sexual Reproduction

Sexual reproduction involves the fusion of two gametes

Sperm and eggs are sometimes produced by the same individual and sometimes produced by different individuals

The sexes of vertebrates are separate but some vertebrates can change sex

Variation is advantageous to species in fluctuating environments

Reproductive cycles

Reproductive cycles in many vertebrates and invertebrates are related to changes in day length

Day length is a reliable indicator of season for timing circannual events such as

reproductive behavior and migration

In many species, the pineal gland secretes melatonin in the dark Increasing day

length (decreased melatonin levels) triggers reproductive behavior

Males of some aquatic animals (ex: sharks, skates, rays) have specialized pelvic fins which allow the sperm to be passed to the female

Penis

The penis evolved independently in insects It is found in all mammals

Some reptiles and birds have a penis but most have a single opening for the reproductive, excretory, and digestive systems called a cloaca

Male Reproductive System

Male Reproductive Structures

Sperm are produced in the seminiferous tubules of the testes but mature in the

epididymide They are stored in the epididymides and vas deferens

The penis contains 3 masses of spongy erectile tissue with distensible blood spaces

that produce erection when blood flow in the veins is inhibited The spongy erectile

tissues become engorged with blood Stimulation is provided by the parasympathetic nervous system

An orgasm occurs as rhythmic muscular contractions compress the urethra and expel the semen This expulsion is termed ejaculation

Fluids Added to Form Semen

The prostate gland produces a secretion that buffers the vaginal pH, which is

normally 3.5 to 4

The seminal vesicles add fructose to nourish the sperm and prostaglandins to promote

contractions in the female

The bulbourethral gland (cowpers gland) produces mucus which lubricates the

penis

Testes

The testes are kept slightly cooler than body temperature because they are suspended outside the body within the scrotum

Each testis contains 250 to 300 lobules, and each of these contains one to three tightly

coiled seminiferous tubules Sperm are produced within the seminiferous tubules The Leydig cells, located between the tubules, function to secrete testosterone

Sertoli cells are located within the tubules They support, nourish and regulate

(stimulate) cells that form sperm

The formation of sperm (called spermatogenesis) is stimulated by testosterone

It promotes the development and maintenance of sexual behavior

It stimulates the development of secondary sexual characteristics such as beard growth, deepening of the voice, etc and has growth-promoting effects

Sperm

The head of a sperm contains the nucleus and acrosome The acrosome contains enzymes that play a role in breaking down the barrier surrounding the egg