Home / Holstein Friesian

Methods for Determining Estimated Breeding Value

different mother from that sire.

If there are enough data for at least 5 sisters, the potential similarity value is

The milk yield of this male based on those five figures will be more accurate.

much more than using the method based on the phenotypic value of its mother.

Evaluation of bull selection by value

Maybe you are interested!

similar to

potential

Methods for Determining Estimated Breeding Value

Milk through the first milk yield of the sister and daughter are the last two steps of the selection process of specialized dairy bulls. Depending on the purpose and demand for dairy cattle farming in each country, there are different evaluation criteria, but the most important is yield. To select HF bulls for milk potential, it is necessary to select through the milk yield of the sister and daughter because the bull itself does not produce milk, so it cannot be evaluated directly on the bull.

The true breeding value is never known, but the estimated value will approach the true value as the number of offspring samples increases. This value is determined from the analysis of all possible sources of information of the

individual, of itself and individuals 2006)

familiar (Nguyen Van Duc et al.,

The breed evaluation program uses a modern form of analysis.

is called the best linear unbiased estimate (BLUP).

The BLUP program has a degree of

high reliability because of use

can be used for most of the

source of information on the bloodline of individuals

and number

data of the properties

status. We can't

know the exact value

same for properties

different status, but a good way to determine breeding value can be determined. Breeding value represents the genetic difference between an individual and the population with which it is compared. The unit used for breeding value is

units of the trait in question. For example, units of value

The milk potential of HF dairy bulls is kg milk/lactation.

Suppose, a HF bull has a breeding value of 400 kg milk/lactation. That value means that cows born to this bull will have 200 kg milk/lactation more than the average of cows born to another father with breeding value (GTG) = 0 assuming the breeding value of the mother cow for milk production = 0, because that individual cow only receives 1/2 of the genes from the father and

fake

set that level

reliability of value

similar to

milk potential achieved

100%. Breeding value is the best estimate of genetic merit that modern technology can provide us to base breeding selection on. In addition, the homologous group is also a factor to consider in the analysis.

Confidence ranges from 0 to 100%. The confidence level of estimated seed value is often divided into 5 levels (Nguyen Van Duc et al., 2006): Very low (040%), low (4160%), medium (6175%), high (7695%), very high

(>95%).

1.3.2.2. Methods for determining estimated seed value

According to Nguyen Van Duc et al. (2006), the main methods for determining breed value include:

a. Similarity value calculated from the average of two kin groups

If the animals are in two related groups, for example, the paternal and maternal groups denoted by R1 and R2 and the corresponding phenotypic mean for the trait we are referring to for breeding value is denoted by PR1 and PR2, the breeding value (GTG) of that individual can be calculated as follows:

GTG


b1 (PR1


Pdan )


b2 (PR 2


Pdan )

Here: R1 and R2 are the paternal and paternal groups and the offspring groups

PR1 and PR2 are the phenotypic means for traits R1 and R2 respectively.

b1 and b2 are calculated from a number of individuals in groups,

relationship

of individuals

in groups with individuals that

We are calculating the same value.

If the breeding value of a bull for a productive trait

The amount of milk is calculated from a group of k daughters and n sisters who share a common

half-blood, value is calculated by the formula:

breed of bull

GTG


b1 (PO


Pdan )


b2 (PPNHT


Pdan )

Here: P0 and PPNHT represent the average phenotype of daughters and half-sisters.

b, Value

adjective

phenotype of the trait under consideration and

related status

If selection is made for some trait, the phenotype can be measured on both its own trait and its related trait. Note that selection based on phenotype of two traits is at least as reliable as

by just

based on only one trait. If X represents

for calculation

state that

value

alike

is calculating and Y represents

for the trait

Regarding trait X, the breeding value is calculated according to the formula:


GTGX

b1 (PX


PX )

b2 (PY


PY )


body

Here:

PX and PY are the phenotypes for traits X and Y of fish.


under consideration.


PX and PX are the herd averages of the traits.

The values ​​of b1 and b2 in the following formulas are calculated as follows:

b1 h 2 x

(rp xp

py /

px )b2


y

b2 (hx rG XGY hy

px /

py )

(rPxPy

px /

py )b1

XY

Here: h2 and h2 are the heritability coefficients of traits X and Y.


px and py are the standard deviations of traits X and Y.

rGxGy and rpxpy are the genetic and phenotypic correlation coefficients between two traits.

Any source of information relevant to the breeding value of an individual can be extended to the above formulas. If parameters such as heritability, genetic correlation and phenotypic correlation are accurately determined, the breeding value can be calculated.

alike

based on the aggregated information will certainly

have degree

high reliability

than when using fewer information sources.

1.3.2.3. Selection of dairy bulls based on breed value and milk potential

a. In the world

Breeding value studies on the milk potential of dairy bulls in the world have been carried out for a long time and have achieved great results.

Zhang et al. (2000) used the BLUP method to estimate the value of

breeds of HF cattle in China and their value

similar to

product

The cyclical milk yield of this population varied from a low of 1,160.29 kg milk/cycle to a high of +2,052.75 kg milk/cycle.

Zwald et al. (2003) concluded that the average predicted transmitting ability (PTA) index for milk yield of the male cows in the herd groups ranged from 238 kg milk/lactation to 700 kg milk/lactation.

Powell et al. (2005), published the country-wise average GTG of

The top 100 cows from 10 countries showed: the highest GTG in Canada (+1785 kg milk/lactation) and the lowest in Australia (+745 kg milk/lactation). Gonzalez Recio et al. (2005) reported that the average GTG of internationally genetically evaluated bulls for milk production was 335 kg milk/lactation.

Mashhadi et al. (2008) reported that the results of a study using HF bulls in the United States and HF Ecuador to breed cows in Ecuador also showed that: if choosing 10% of HF bulls with the highest GTG, the GTG of HF bulls in the United States reached +760 kg of milk/cycle and HF bulls in Ecuador reached +576 kg of milk/cycle. The fluctuation in GTG was also similar to that of HF cows raised in Iran, fluctuating from 265 kg to +1287 kg of milk/cycle.

Zhang et al. (2000) used the BLUP method to estimate the GTG of HF cows in Beijing, China and found that the GTG of milk yield varied from 1,160.29 kg milk/lactation to +2,052.75 kg milk/lactation.

b. Domestic

In Vietnam, Nguyen Van Thuong et al. (1992) determined the GTG of 4 bulls with the highest milk yield, including 3 pure HF bulls with numbers 222, 223 and 111 and one hybrid HF bull with number 109 with 3/4HF1/4LaiSind.

Vo Van Su

et al. (1996), have

Estimated GTG of sires

Holstein Friesian on the two best dairy farms in our country, Moc Chau and Lam Dong, showed the highest GTG in male breed number 26.

+278.07 kg milk/cycle and lowest at

milk/cycle.

male number

167 is 127.21 kg

Pham Van Gioi (2008) said, the value

alike

average estimate

of the entire group of HF fathers used to breed HF cows in the North

Our country is 0.02 kg of milk/cycle, with an average reliability of 46.3%.

Pham Van Gioi (2008), studying the genetic nature of HF bulls through imported semen sources at dairy farms in Moc Chau, Tuyen Quang and Lam Dong, said that the highest estimated GTG was +1465.9 kg of milk/cycle and the lowest was +378.6 kg of milk/cycle, with

reliability ranges from 67 to 79%.

Le Ba Que (2013), estimated GTG of 09 imported breeding bulls

From the US and Cuba, the results obtained: the male with the highest GTG was

+1,064.58 kg of milk/cycle and the lowest GTG male was +36.62 kg, proving that the quality of this imported HF bull herd is uneven because of the large deviation in GTG.

Le Van Thong et al. (2013), implementation

topic

Ministry Level

stage

2008-2012 research on 12 HF bulls of Cuban and American origin in Moc Chau (Son La) and Duc Trong (Lam Dong) determined that the estimated GTG of the first milk potential of the daughter herd ranged from +53.15 kg milk/cycle to +1,232.8 kg milk/cycle.

Le Van Thong et al. (2014), implementation

topic

House Level Independence

2009-2013 period, GTG research estimates on milk potential

through the milk yield of the sister cows of 15 bulls born in

Vietnam reported that the GTG for milk potential ranged from 899.1 kg milk/cycle to +668.0 kg milk/cycle.

1.3.2.4. Application of breed values ​​in selecting specialized dairy bulls

The breeding value of an individual is used to decide whether to select that individual for breeding or not.

a. History

value use

similar to

milk potential to

cattle quality assessment

Holstein Friesian male

HF bulls do not directly produce milk like HF cows, but

They can pass on their genes for milk production to the next generation. Therefore, to evaluate the milk production ability of a bull, we must evaluate the milk potential through the milk production of his sisters and daughters.

Value

alike

Estimates of milk potential

is the quantity represented

the best genetics that modern technology can provide

We use this as a basis for selecting male dairy breeders. Through price.

Breeding value can know the ability to pass on the milk-producing genes of each HF bull to the next generation. HF bulls with high breeding value in terms of milk potential are male individuals with good quality in terms of milk production ability. The offspring born from individuals with high breeding value

treat

milk potential

high will have

milk yield

higher than

offspring born to sires of low breeding value.

b. History

value use

similar to

milk potential to

bull breeding

Holstein Friesian

In the state-level independent project "Research on testing, evaluating and selecting the next generation of HF breeding bulls" in the period 2009-2013, Trung

The Central Livestock Breeding Center has established TCCS 04 standard:

2013/VINALCA on Holstein Frisien bulls grading method

Ranking. The ranking principle is to rank according to the magnitude of the breeding value or production index. Specifically, the bull with the largest breeding value or production index is ranked first (one), the individual with the second, third, etc. largest breeding value or production index continues to be ranked in the next position 2, 3, etc. (Institute of Animal Husbandry, 2013).

In the process of selecting and testing male bulls that pass away,

use the results of the assessment step

value

milk potential

through

milk yield

of the daughters of each bull to

selection is

most accurate. Therefore, when ranking bulls for milk potential, bulls with high breeding value for milk potential are ranked first and ranked in order from highest to lowest.

c. History

value use

similar to

milk potential to

program building

suitable breeding for Holstein Friesian cattle

Nguyen Van Duc et al. (2008), research determined


value

on the milk potential of individual purebred and crossbred HF bulls whose semen is being used to inseminate cows in Vietnam. The project

published value

milk potential

of 973 HF bulls

purebred and 5 crossbred HF sires, contributing significantly to the Vietnamese dairy cattle breeding work in order to build a mating program to create individuals with high breeding quality. From the results obtained, the authors proposed to use these breeding values ​​in mating in breeding and multiplication work according to the breeding program to create a high-quality dairy herd: rapidly increasing in output and rapidly increasing in quantity. The specific breeding program is as follows:

For the best male breeding group (GTG over 600 kg milk/cycle)

need to be

Preferential mating with individuals

best cow in the herd

to create embryos and use those embryos for selecting bull and cow herds.

For good male breeding group (GTG from 100 to 600 kg of milk): should be mated

with nucleus herds to create nucleus herds and breed

(400<GTG<600 kg milk/cycle); create a selective herd of breeding and production cows (200<GTG<400 kg milk/cycle) and create a selective herd of production cows (100<GTG<200 kg milk/cycle).

Comment


Agree Privacy Policy *