Sperm Production Ability Of Bulls And Some Influencing Factors

metabolism, fermentation in the rumen to digest food and the temperature of the external environment. The higher the productivity of the cow, the stronger the metabolism, the more heat is generated. Digestion of rough, indigestible food increases heat generation in the rumen. When the heat generated in the body is greater than the heat released from the body into the environment, the body temperature exceeds 390C and the cow appears to be heat stressed.

Dairy cows are homeothermic animals, to maintain a stable state, cows need to be in thermal equilibrium with the environment (Kadzere and Murphy, 2002). Because temperature and humidity are very important for the ability to adapt

of cattle in different climates, so people have built an index

Heat-humidity index (THI) is related to heat stress in cattle.

1.2.2. Sperm production capacity of breeding bulls and some influencing factors

Maybe you are interested!

1.2.2.1. Sperm production capacity of breeding bulls

There are many criteria in the production of frozen semen.

target

number rating

The quantity and quality of semen before being put into frozen production such as: ejaculate volume, sperm motility, sperm concentration, pH, color, percentage of live sperm, percentage of abnormal sperm, total number of active sperm, sperm resistance. Meanwhile, sperm motility after

Thawing is the most important criterion to evaluate the quality of frozen semen.

frozen. Qualified semen for production is semen from exploitations that simultaneously meet all of the above criteria. In which, ejaculate volume, sperm motility, sperm concentration, live sperm rate, total number of active sperm, sperm motility after thawing are the main criteria affecting the ability to produce frozen semen of breeding bulls.

a. Amount of ejaculation

Ejaculate volume (V) is the volume of semen from one ejaculation.

(ml/time). The amount of ejaculation is closely related to gender, age, and sexual activity.

care, diet, testicular size, season, level

Pre-exploitation sexual stimulation, the ejaculatory reflex and the semen extraction technique. In addition, the semen extraction distance also affects the amount of ejaculate: too short a semen extraction distance results in less ejaculate and too long a semen extraction distance results in more ejaculate (Cheng, 1992).

According to Hiroshi (1992), the amount of ejaculate ranges from 2 to 10 ml.

Research by Brito et al. (2002) on Brazilian bulls showed that the amount of ejaculate varied from 6.0 to 7.8 ml; in Bos taurus bulls it was 7.0 ml and in Bos indicus bulls it was 6.6 ml. Sarder (2003) reported that the amount of ejaculate in Pakistani bulls was 56 ml/time of exploitation.

In Vietnam, research on F3HF crossbred cattle, Nguyen Van Duc and

cs. (2004) published that the amount of ejaculate was 4.11ml. Phung The Hai et al.

(2009), research on young HF bulls born in Vietnam, published, the amount of ejaculate is 5.42ml. Le Ba Que et al. (2013) published, the average amount of ejaculate of HF bulls is 6.99ml.

b. Sperm motility

Sperm motility (A) is an indicator showing the number of active sperm moving straight in semen and is calculated as a percentage ranging from 0% to 100%.

Tran Tien Dung and colleagues (2002) said that depending on their vitality, sperm will move in one of three ways: straight forward, rotating, and swaying.

Only spermatozoa that move forward are capable of participating in the fertilization process. Therefore, people evaluate semen quality through

by estimating the percentage of straight-moving sperm or the "motile" level of the

seminal fluid microscopic surface created by sperm motility.

Bajwa (1986), study

in Pakistan announced

sperm motility

ranged from 67 to 70%. Hiroshi's (1992) study on bulls

HF breed in Japan announced sperm motility ranging from 60 to

90%. Sugulle (1999), published

sperm motility

bull breeding at

Bangladesh achieved from 60 to 68%. Research by Brito et al. (2002) in

Brazil shows bull sperm motility

Bos taurus reaches from

57.5 to

61.2% and Bos indicus cattle reached 59%. Hoflack et al. (2006) reported that sperm motility of HF bulls in Belgium ranged from 40 to 95%.

In Vietnam, Nguyen Van Duc et al. (2004) reported that the average sperm motility of crossbred HF bulls was 61.77%. Phung The Hai et al. (2009), in a study on young HF bulls born in Vietnam, reported that the average sperm motility was 60.28%. Le Ba Que (2013), in a study on HF cattle imported from the US and Cuba, reported that the average sperm motility was 66.39%.

c. Sperm concentration

Sperm concentration (C) is the number of sperm in one ml of semen (billion/ml). In cattle, sperm concentration ranges from 200 million to 3,200 million sperm/ml, with an average of 1,200-1,500 million sperm/ml (American

Breeders Service, 1991). If the sperm concentration reaches 800 million/ml, then it is achieved.

Standards for preparation and freezing (Ministry of Agriculture and Rural Development, 2003; 2008; 2014).

Sperm concentration has practical scientific significance, it determines the number

Sperm count per semen extraction to classify semen quality, decide to discard or use for the next stages. Sperm concentration

spermatozoa when combined with V and A give the total number of forward moving spermatozoa in each ejaculate.

In a study on HF bulls raised in the United States, Garner et al.

(1996) reported that the average sperm concentration was 1.5 billion/ml. Brito et al.

(2002), a study on 107 breeding bulls in Brazil found that the concentration of

Bull sperm count reached 1.3 to 1.5 billion/ml. Sarder (2003), research in

Pakistan says local HF-crossbred bulls have sperm concentrations that range

ranging from 1.131 to 1.471 billion/ml. Sugulle et al. (2006), in a study on HF crossbred cattle in Bangladesh, reported that sperm concentration ranged from 0.983 to 1.483 billion/ml. Muino et al. (2008) reported that adult HF bulls raised in Spain had an average sperm concentration of 1.18 billion/ml.

In Vietnam, the sperm concentration of HF cows is 1.229 billion/ml (Nguyen Xuan Hoan, 1993); 1.215 billion/ml (Le Ba Que et al., 2009). Phung The Hai et al. (2009), research on young HF bulls born in Vietnam, announced the average sperm concentration was 1.07 billion/ml. Le Van Thong et al. (2013), research on HF cows imported from Australia, announced the average sperm concentration was 1.03 billion/ml.

d. Percentage of live sperm

The rate of live sperm is closely related to the fertilization rate of sperm. Based on the principle that the membrane of dead or dying sperm can allow dyes to penetrate, due to the disorder of the permeability of the sperm membrane. Meanwhile, the sperm membrane of living sperm does not allow dyes to penetrate, so it does not take color when stained. In this way, people used eosin dye to stain dead sperm, then counted them under a microscope and calculated the survival rate.

Proportion

live sperm

depending on the species, degree

age, mode

level of care

nurturing, extraction, dilution environment... (Hiroshi, 1992).

Hoflack et al. (2006) reported that the live sperm rate in HF bulls was from 77.25 to 97.67%, higher than that in Belgian Blue bulls from 29.5 to 87.25%. Research on HF bulls in Belgium Hoflack et al. (2008) reported that the live sperm rate was 86.3%. According to Muino et al. (2008), the study

Research on HF bulls in Spain showed a rate of 87.0%.

live sperm rate

According to the research results of Phung The Hai et al. (2009), research on young HF bulls born in Vietnam showed that the average live sperm rate was 71.75%. Le Ba Que (2013), research on HF cattle imported from the US and Cuba showed an average activity of 78.65%.

e. Total number of straight sperm/extraction

Total number of live spermatozoa in semen (VAC) is an important synthetic index to evaluate the ability to produce frozen semen of each bull, calculated as the product of V*A*C. Ejaculation volume, sperm motility and sperm concentration are the three indexes that most clearly affect the quantity and quality of semen of bulls in frozen semen production and are the decisive indexes for frozen semen production. It is closely related to the amount of preparation medium and positively correlated with the number of doses of straw semen produced in one collection.

Garner et al. (1996) reported that the total number of spermatozoa in a single extraction

The cost of HF bulls raised in the United States is 6.20 billion/time exploited.

Research by Brito et al. (2002) showed that the total number of sperms in one extraction on HF bulls in Brazil was 8.2 billion/extraction.

Phung The Hai (2009), total number of straight spermatozoa of bulls

HF breed born in Vietnam is 4.91 billion/exploitation. Le Van Thong and cs.

(2013), research on HF cattle herd in Moncada announced that the winning motility in one exploitation was 5.46 billion.

f. Sperm motility after thawing

total

pure

The produced straw semen is stored at a deep freeze of 1960C and must be thawed before use. Sperm motility after thawing

(Asgd %) is the most important index to evaluate the quality of frozen semen.

frozen. The quality of frozen semen is influenced by many factors such as: quality of fresh semen used for semen production, semen production technique, dilution environment, freezing resistance of sperm and thawing technique.

Sperm motility after thawing has a great influence on the outcome.

Conception in cows: if sperm motility after thawing is high, conception rate is high and vice versa.

According to Phung The Hai (2009), the sperm motility after thawing of HF bulls born in Vietnam was 40.44%. Le Van Thong et al.

(2013), research on HF cattle herd in Moncada, published post-thaw infection rate was 41.28%.

active essence

1.2.2.2. Some main factors affecting the semen production capacity of breeding bulls

a. Breed and individual

Depending on the breed, size, metabolism, and ability to adapt to climate, the quantity and quality of semen will vary. For example, temperate bulls (800-1000 kg) can produce 89ml or even 1015ml of semen each time they are harvested;

Meanwhile, Vietnamese yellow cows only give 35ml (Ha Van Chieu,

1996). Cattle of temperate origin imported into our country have poor adaptation to the summer climate, so the amount of semen is reduced and the virility is also reduced (Nguyen Xuan Trach, 2003).

In the same breed, the quantity and quality of semen of each individual

are often different (Ha Van Chieu, 1996; Phung The Hai, 2009; Le Van Thong et al., 2013).

b. Age

The quantity and quality of semen of mature bulls are usually more and more stable than that of young bulls. Bulls produce good semen and

most stable at

age from

3 to 6 years old. Semen of old bulls

reduce rate

live sperm, increased rate

sperm count

shape and reduce the ability

Freeze-able (Hiroshi, 1992).

Ha Minh Tuan et al. (2012), in a study on a herd of breeding bulls raised in Moncada, showed that the average ejaculate volume of HF bulls at 18-24 months of age was 4.82 ml/session; at 25-36 months of age, it was 6.26 ml/session; and at 49-60 months of age, it was 7.51 ml/session.

The lifespan of a breeding bull can reach 1820 years, but due to many

different causes so often only (Nguyen Xuan Trach et al., 2006).

c. Weather and climate

used

use up to 8 years old

every opportunity

body

living differently, bulls are directly affected by

weather and climate, mainly temperature, humidity, light, etc. According to the law of ecological limits (Ha Van Chieu, 1999), each species or each organism has a suitable range of a certain climatic factor. In addition to the limit

The appropriate limit of the body's ability to live will affect and be affected.

resonance by environmental factors. In the relationship between the external environment and organisms, the impact of the environment on reproduction is the most important. The impact of the environment on the production of male semen is very complicated, it is difficult to determine which factor is important at a certain time.

In temperate countries, semen quality is worst in winter, best in summer and fall mainly due to light. However, in our country, semen quality is often worst in summer due to heat, best in winter-spring, much lower in summer, and higher in fall (Nguyen Xuan Trach et al., 2006).

Vilakazi and Webb (2004), in a study on Bos taurus cattle, found that the rate of abnormal sperm increased in summer and autumn, and semen quality in winter was significantly better than in summer.

Semen quantity and quality are significantly affected by season,

Bull semen in the rainy season has a quantity

and quality

best

(Bhakat et al., 2011). The quantity and quality of semen of HF bulls raised in Vietnam are clearly affected by seasonal factors (Phung The Hai et al., 2013).

d. Nutrition

Comment