eChapters

Modern Semen Evaluation Methods

1. Fluorescent Microscopic Evaluation
2. In-vitro Fertility Test
3. Enzyme Estimation

1. Fluorescent Microscopic Evaluation

1.1. Acrosomal Integrity (Giemsa method and FITC-PSA assay)

The acrosomal integrity of the spermatozoa was detected using Fluorescence isothiocyanate – Pisum sativum agglutinin (FITC-PSA) staining procedure adopting method of Mendoza et al. (1992). Pisum sativum agglutinin (PSA) when conjugated to Lectin FITC marks the intact acrosome with bright green fluorescence. PSA is an agglutinin from edible pea that binds to glycoconjugates of acrosomal matrix or outer acrosomal membrane. It has affinity for terminal α –D-glucosyl and α-D-mannosyl residues of glycoproteins and it binds specifically to sugar α-mannoside found in acrosomal content.

The semen evaluation is of great importance in predicting fertility of the male. There are several parameters to evaluate the semen quality. Usually bucks with good semen samples have good fertility and bucks with poor or very poor semen samples are invariably infertile or sterile. A single test is never sufficient to assess the semen quality and the examiner should be acquainted with several tests to evaluate the semen. The semen should be examined with in a shortest possible period after ejaculation and the ejaculate must be properly protected and handled until examination. Semen can be evaluated by following methods

1. Macroscopic test
2. Microscopic test
3. Metabolic test

The following objectives are accomplished by semen dilution/ extension

• Preservation of semen potential over a long period of time.
• Increase in the number of services per ejaculate. Ideally approximately 40 does can be inseminated from diluted/ extended semen of a single ejaculate.
• Extenders provide the spermatozoa with a medium in which they are able to remain viable and fertile for a prolonged time period. An ideal extender should be able to provide a conducive environment to facilitate sperm survival and modify the sperm structure to prepare them for freezing through the following properties:
• It should be isotonic with blood and should maintain this during preservation.
• It should have capacity of maintenance of pH (6.6-6.8) with high buffering capacity in that range.

Hygienic collection of semen is an integral part of the artificial insemination process. Semen collection implies mounting a teaser doe or a dummy. Therefore, proper semen collection deserves the utmost attention. Sexual efficiency is measured by the percentage or successful semen collections among attempted collections. When males are allowed to female teaser, the male exhibits characteristic behavioural symptoms such as sniffing, nudging or mounting at that time it is necessary for the operator to attempt an approach. This approach has to be done quietly to avoid a fear reflex in the male. The male, even if it mounts the female, deviation of its penis into the receptacle. Under the circumstances, the operator should not more from his squatting position, so that the male does not associate the two events. The animal generally comes back by itself to attempt remounting the female and will serve the artificial vagina. The operator should also stimulate the male by voice.

The animals are mostly social ones and prefer living in herds. In each species there are certain rules for group survival, cohesion, defence and also for propagation. The basic patterns of male sexual behaviour appear to be innate in nature. Kids of both sexes are very often seen exhibiting sexual display during play and mounting is seen most commonly. In females the sexual receptivity is restricted to few hours or days near the estrous phase of the estrous cycle, while in males the sexual receptivity is grossly permanent. The physiological signals for arousal of sexual motivations originate from gonadal steroid balance. However, the secretion of gonadal steroids is not permanent. In males the androgen secretion is in the form of several peaks within 24 hours reflecting the pulsatile release of pituitary gonadotropins. However, the total amount of androgen in males is almost constant practically for day to day. In females the secretions of estrogens are restricted only during few days (follicular phase) of the estrous cycle.

India has rich diversity of goat genetic resources and as per 20^th livestock census (2019), there are 148.88 million goats in India. They are mostly found in arid and semi-arid regions of the country and one of the mainstay of dryland agriculture system. Out of 148.88 million, around half of them (75 to 60 million goats) are found in Rajasthan (20.84 m), Uttar Pradesh (14.48 m), Madhya Pradesh (11.06 m), Maharashtra (10.6 m), Tamil Nadu (9.89 m) Karnataka (6.17 m) and Gujarat (4.66 m). Out of total goat population, only 35 % of the goats are of either pure breed or upgraded nature resembling the some of the local breeds. There is huge scope to improve the productivity through use of assisted reproductive tools like artificial insemination and estrus synchronization in field condition to upgrade the non-descript population in relatively shorter period of time as compared to natural services.

Occasionally some diseases can be noticed in male animals, which are responsible for the reduced reproductive performance of the bucks. Sometimes these diseases can damage or obstruct the male reproductive passage and responsible for the infertility and sterility in the bucks. This type of infertility may be associated with pathology of testes, epididymis, vas deferens, accessory sex glands, and urethra or may be associated with abnormal semen production due to congenital or hereditary causes or due to acquired causes.

Nutrition is the key factor affecting the production as well as the reproduction efficiency in all the animals therefore proper and balanced nutrition is the prerequisite to attain and utilize the full reproductive potential of the animals. All the nutrients like energy, protein, minerals and vitamins need to be properly balanced in the diet of animals. Energy and protein are the major nutrients required in the greatest amounts and should be in the topmost priority in order to optimize reproduction. Although minerals and vitamins are required in low amount, but very much essential as a cofactor and coenzymes in the reproductive process of the animals and deficiency of these nutrients might affect the overall reproductive efficiency of the animals.

The goat rearing on extensive rearing system has been practiced since ancestry for livelihood and nutritional security of poor, landless and marginal farmers of our country with the flock size ranging from 2-10 goats. However, in the recent past, goat rearing is shifting towards semi-intensive and intensive rearing systems for commercial purposes with flock size ranging from 25 to 500. The goats reared in small flocks needs minimal housing facilities following the scientific principles with low-cost structures. On the other hand, elaborate housing is generally recommended for goats raised under large scale commercial production systems. Separate housing arrangements for different categories of animals viz. growers, pregnant females, lactating females, breeding males, etc. are to be ensured for rearing goats scientifically for harnessing maximum output sustainably.

Ian Donald in the year 1956 used the one-dimensional A-mode (amplitude mode) to measure the parietal diameter of the fetal head and thus introduced the ultrasound in diagnostic and medicine. Ultrasonography does not use radiation or powerful magnetic field as source of energy and the equipment cost is usually affordable. This modality involves the use of sound waves in viewing the longitudinal, sagittal and transverse planes for both testes . Sound is measured in cycles per second or hertz (Hz); the audible range of sound is from 20-20,000 Hz. Diagnostic ultrasound is usually in the range of 1–20 megahertz (MHz).

The speed of sound depends on the tissues through which it propagates because density and compressibility change the speed, the sound wave travels. On an average the assumed speed of sound in soft tissue is 1540 m/s.

India is the largest goat producing countries in the world exhibiting rich diversity between and within goat breeds. The implementation of a genetic improvement programme requires a clear breed-based breeding objectives and selection criteria, tailored to the needs of goat farming community. Indigenous goat breeds bear a great degree of adaptability for climatic stress, tropical diseases and low quality feed resources, require low inputs for enhancing productivity, thus, little investment along with use of high merit bucks bring a great change in the economy of the farmers. There are currently 37 recognized goat breeds in the country which are kept mostly in small herds on extensive or partial semi-intensive feeding system. Productivity of Indigenous goats, however, observed less than their actual genetic potential and attributed to low input system, lack of suitable breed specific structural genetic improvement programme and poor adoption of technologies. A buck is the most important animal in the herd. A breeding male or buck contributes 50% of the genetic merit of the herd and also determine the future improvement rate.

Globally there is growing demand for small ruminant production especially, goats for meat and milk purposes to feed the ever-increasing human population. As per 20^th Livestock Census released by Department of Animal Husbandry & Dairying, the Goat population in the country in 2019 is 148.88 million showing an increase of 10.1% over the previous census Out of 148.88 million Indigenous Goats (Including Non-descript), 27.4% are pure breed, 9.1% are graded breeds and the remaining 63.5% are non-descript breeds. The goat population has increased at a faster growth rate in India and varied from 0.94 to 5.10% with an average of 3.05% during 1951-2013 in spite of about 41% slaughter and about 15% natural annual mortality. India produced 21.71% of the milk, 10.47% of the meat and 13.15% of the fresh skins of the world goat production worth of Rs. 1,06,335 million per annum. The goat husbandry also generates about 4.2% rural employment over 500,000 remote villages. It contributes nearly 8.5% of the total GDP from livestock sector to Indian agriculture production system. So, to increase the productivity per goat, we need to improve the breed quality scientifically.

The goats play a vital role in the economy of the poor and marginal farmers of rural India. Notwithstanding the fact that the goat population has shown a steady growth over the year’s very little effort has been taken for genetic improvement at farm level. As per 20th Livestock Census, 27.74% of the livestock population is Goats. Out of 148.88 million Indigenous Goats (Including Non-descript), 27.4% are pure breed, 9.1% are graded breeds and the remaining 63.5% are non-descript breeds. So, to increase the productivity per goat, we need to improve the breed quality scientifically. Artificial insemination (AI) using frozen semen is practiced to produce superior progeny and to accelerate the up gradation of stock. The conception rate with AI is lower but it has great potential to multiply superior quality of goat with faster rate. This technique also spread elite genetic material throughout a population with increased rate of genetic improvement. This technique is also important for the breed conservation process and has paved the way for other reproductive biotechnologies. The sufficient elite germplasm of male buck is not available throughout the country to cover breeding programmed by natural mating. AI is the best solution to improve the quality and productivity per goat.

The male genital system consists of:

1. The pair gonads, the testes
2. Epididymis
3. Vas deference or ductus deference
4. Accessory glands (Seminal vesicles, prostate glands, & bulbo-urethral glands)

• In male animals, endocrine regulation of reproduction is mainly controlled by pituitary gonadotrophins and gonadal androgens. It is not same as in females as there is only negative feedback controls in case of male while it is positively as well as negatively feedback control in females. In other words the synchrony of pituitary gonadotrophins with gonads in male is non cyclic while in female it is cyclic i.e. after castration the pulse frequency of LH and FSH is retained
• Sex Hormones are sex specific e.g. estrogen and progesterone works primarily in females and testosterone in males but sex specificity is limited as far as sexual behaviour is concern. As estrogen injection in castrated buck recovers the maleness while testosterone injection in ovariectomized female maintain the receptivity for male up to certain extent.
• Hypothalamus acts as interface between nervous system and endocrine system. GnRH synthesized in neurons in hypothalamus, released at nerve endings episodic manner and transferred via hypophyseal portal system to anterior pituitary to stimulate the secretion of gonadotrophins.

1. Market information includes

a) Market intelligence

b) Market news

c) Both a and b

d) Marketing

2. Historical nature of market information is

a) Market intelligence

b) Market news

c) Market information

d) Marketing

3. Current information about markets is

a) Market intelligence

b) Market news

c) Market information

d) Marketing

1. International trade contributes and increases the world _________

a) Population

b) Inflation

c) Economy

d) Trade Barriers

2. Free international trade maximizes world output through________.

a) Countries reducing various taxes imposed.

b) Countries specializing in production of goods they are best suited for.

c) Perfect competition between countries and other special regions

d) The diluting the international business laws & conditions between countries.

3. Domestic company limits it’s operations to ___________ political boundaries.

a) International

b) National

c) Transnational

d) Global

1. Government is concerned with the marketing system for

a) The quality of commodities at the lowest price

b) Maximum price for surplus produce

c) Steady income from marketing of commodities

d) Safeguard the interests of the groups associated in marketing

2. Which of the following statements are correct ?

i) The Jute Corporation of India is providing minimum price support that assists jute cultivators in all the states of India.

ii) The company purchases jute at the fixed minimum price when market prices declined and later sells to jute mills.

iii) The jute industry suffers from wide fluctuations in supply and price due to changes in the cultivated area and due to the effects of the factors associated with weather.

a) i and ii only

b) i and iii only

c) ii and iii only

d) All of the above

1. In ____________ market, future buying and selling of commodities will take place at current time

a) Forward

b) International

c) Perfect

d) Spot

2. Forward Contracts (Regulation) Act

a) 1952

b) 1962

c) 1958

d) 1963

3. _____________ had also recommended strengthening of existing commodity exchanges and forward markets commission

a) Kuhsro committee

b) Rangarajan committee

c) Forward market committee

d) Kabra committee

1. In developed countries, the major objective of price policy is to____________

a) Prevent drastic fall in agricultural income

b) Increase the agricultural production

c) Both a & b

d) None of the above

2. In developing economies it is to _____

a) Prevent drastic fall in agricultural income

b) Increase the agricultural production

c) Both a & b

d) None of the above

3. The important objectives of the new agricultural policy are _____

a) Augment facilities for All-Round Development

b) Infrastructural Development

c) Reviving and strengthening Co-operatives and local communities

d) All the above