Animal breeding Questions in English

(B) mule is a hybrid animal produced through interspecific hybridization.
It is the result of a cross between a male donkey ($Equus$ $asinus$) and a female horse ($Equus$ $caballus$).
This process is a type of animal breeding where two different but related species are mated to combine desirable traits.
Therefore,the correct option is $B$.

(D) The statement 'Inbreeding leads to the accumulation of desired genes' is false.
Inbreeding increases homozygosity,which helps in the accumulation of superior genes and the elimination of less desirable genes. However,it also leads to the accumulation of harmful recessive genes that are exposed by selection.
Continued inbreeding,especially close inbreeding,usually reduces fertility and productivity,a phenomenon known as 'inbreeding depression'.
Therefore,while it helps in selecting desired genes,it does not exclusively lead to the accumulation of only desired genes; it also accumulates harmful ones.

(A) Cross-breeding is a breeding strategy where superior males of one breed are mated with superior females of another breed.
This allows the desirable qualities of two different breeds to be combined into the progeny.
Santa Gertrudis is a well-known breed of cattle developed in the United States by crossing Shorthorn bulls with Brahman cows,which is a classic example of cross-breeding.
Therefore,both the statement $(S)$ and the reason $(R)$ are correct,and $R$ provides the correct explanation for $S$.

(D) mule is the offspring of a male donkey and a female horse.
This process involves mating between two different species of the same genus $(Equus)$.
This specific type of breeding,where mating occurs between two different species,is known as Interspecific hybridization.
Therefore,the correct option is $D$.

(A) The Santa Gertrudis breed is a classic example of $Cross-breeding$.
It was developed in Texas by crossing $Brahman$ bulls $(Bos \, indicus)$ with $Shorthorn$ cows $(Bos \, taurus)$.
$Cross-breeding$ allows the desirable qualities of two different breeds to be combined into the progeny.

(C) Inbreeding refers to the mating of more closely related individuals within the same breed for $4-6$ generations. Continuous inbreeding increases homozygosity. This process exposes harmful recessive genes that are otherwise masked by dominant alleles in a heterozygous state. These recessive genes then express themselves,leading to inbreeding depression,which reduces fertility and productivity.

(C) In animal breeding,continuous inbreeding (mating between closely related individuals) increases homozygosity. This process exposes harmful recessive genes that are otherwise masked in heterozygous conditions. The accumulation of these deleterious recessive alleles leads to 'inbreeding depression',which results in a reduction of fertility and productivity in the offspring. Therefore,the fertility of offspring decreases when the proportion of homozygosity increases.

(B) Cross-breeding is a method of animal breeding where a superior male of one breed is mated with a superior female of another breed. This allows the desirable qualities of two different breeds to be combined into the progeny. For example,Hisardale is a new breed of sheep developed in Punjab by crossing Bikaneri ewes and Marino rams.

(A) Interspecific hybridization is a breeding method where individuals of two different related species are crossed to combine desirable features in the progeny.
When a male donkey ($Equus$ $asinus$) is crossed with a female horse ($Equus$ $caballus$),the resulting offspring is known as a mule.
Conversely,when a male horse is crossed with a female donkey,the offspring is known as a hinny.
Therefore,the correct answer is a mule.

(A) Outcrossing is the practice of mating animals of the same breed that have no common ancestors on either side of their pedigree up to $4-6$ generations.
It is the best breeding method for animals that are below average in productivity in milk production,growth rate in beef cattle,etc.
It helps to overcome inbreeding depression because it increases heterozygosity,which masks the expression of harmful recessive genes.
Therefore,it does not lead to the accumulation of harmful recessive genes,nor does it increase homozygosity.

(A) Inbreeding refers to the mating of more closely related individuals within the same breed for $4-6$ generations. This process increases homozygosity,which is necessary for the evolution of a pure line in any animal. It exposes harmful recessive genes that are eliminated by selection. Therefore,it helps in the accumulation of superior genes and the elimination of less desirable genes,thereby increasing the opportunity for genetic improvement.

(A) The correct matches are as follows:
$(1)$ Cross-breeding: This involves mating between a superior male of one breed and a superior female of another breed. This allows the desirable qualities of two different breeds to be combined in the progeny. Thus,$(1)-(P)$.
$(2)$ Out-crossing: This is the practice of mating animals within the same breed,but having no common ancestors on either side of their pedigree up to $4-6$ generations. Thus,$(2)-(Q)$.
$(3)$ Interspecific hybridization: This involves mating between male and female animals of two different related species. An example is the mule,produced by crossing a male donkey and a female horse. Thus,$(3)-(R)$.
Therefore,the correct sequence is $(1)-(P), (2)-(Q), (3)-(R)$.

(C) The animal shown in the figure is a $Santa \ Gertrudis$ cow.
$Santa \ Gertrudis$ is a breed of cattle developed in the United States by crossing $Brahman$ bulls with $Shorthorn$ cows.
This breed was developed to combine the heat and insect resistance of the $Brahman$ cattle with the superior beef production qualities of the $Shorthorn$ breed.

(D) The animal shown in the figure is a mule. $A$ mule is a hybrid animal produced by interspecific hybridization,which involves the mating of a male donkey and a female horse. This process is a form of outbreeding used in animal husbandry to combine desirable traits from two different species.

(A) Inbreeding refers to the mating of more closely related individuals within the same breed for $4-6$ generations.
Continued inbreeding,especially close inbreeding,usually reduces fertility and productivity.
This process exposes harmful recessive genes that are eliminated by selection.
However,it also leads to the accumulation of harmful recessive genes if not managed properly,which can decrease the biological fitness of the population.

(C) Interspecific hybridization is a breeding method where male and female animals of two different related species are mated. The progeny obtained from such a cross are often referred to as hybrids. $A$ classic example is the mule,which is produced by the mating of a male donkey and a female horse.

(D) The correct answer is $D$.
Inbreeding refers to the mating of more closely related individuals within the same breed for $4-6$ generations.
This process increases homozygosity,which is essential for the evolution of a pureline in any animal.
By mating related individuals,harmful recessive genes are exposed and eliminated,and desirable traits are concentrated,leading to the development of homozygous purelines.

(B) : In interspecific hybridisation,a species is mated with a different related species of the same genus.
Interspecific hybrids are generally difficult to produce,but they are important in plant breeding,particularly in breeding for disease resistance.
This is also called intrageneric hybridisation.

(A) $Outbreeding$ is the breeding of unrelated animals, which may be between individuals of the same breed (but having no common ancestors), or between different breeds (cross-breeding) or different species (interspecific hybridization).
$Outbreeding$ is an important strategy of animal husbandry as it helps to overcome inbreeding depression, which occurs due to continuous inbreeding.

(C) Cross-breeding is a breeding strategy in animal husbandry where superior males of one breed are mated with superior females of another breed. This allows the desirable qualities of two different breeds to be combined into the progeny. The progeny may be used for commercial production or further selection to develop new stable breeds.

(D) mule is produced by the mating of a male donkey and a female horse.
Since the donkey and the horse belong to two different species,this process is known as interspecific hybridization.
Interspecific hybridization is a breeding method where males and females of two different related species are mated to combine desirable features in the progeny.

(A) $MOET$ stands for Multiple Ovulation Embryo Transfer technology. In this process,a cow is administered with hormones,with $FSH$-like activity,to induce follicular maturation and superovulation. Instead of one egg,which is normal per cycle,$6-8$ eggs are produced. The cow is then either mated with an elite bull or artificially inseminated.

(B) Cross-breeding is a method of animal breeding where a superior male of one breed is mated with a superior female of another breed.
This allows the desirable qualities of two different breeds to be combined into the progeny.
Out-crossing involves mating animals of the same breed that have no common ancestors for $4-6$ generations.
Interspecific hybridization involves mating between males and females of two different related species.
Inbreeding refers to the mating of more closely related individuals within the same breed for $4-6$ generations.

(B) Hisardale is a new breed of sheep developed in Punjab by crossing Bikaneri ewes and Marino rams.
This breed was developed through the process of cross-breeding to improve the quality and quantity of wool production.
Therefore,the correct option is $B$.

(B) mule is a hybrid animal produced by interspecific hybridization,which is a type of outbreeding.
It is the result of a cross between a male donkey ($Equus$ $asinus$) and a female horse ($Equus$ $caballus$).
Therefore,$A$ represents the male donkey and $B$ represents the female horse.

(B) The Hirsadale breed of sheep is a cross-breed developed in India.
It was created by crossing Marino rams with Bikaneri ewes.
This cross-breeding program was aimed at improving the quality of wool produced by the sheep.

(D) High milk-yielding breeds of cows are obtained through advanced animal breeding techniques like $MOET$ ($Multiple$ $Ovulation$ $Embryo$ $Transfer$ $Technology$).
$1$. $Superovulation$: Hormonal treatment is given to induce the production of more than one egg per cycle.
$2$. $Artificial$ $insemination$: Semen from a superior bull is used to fertilize the eggs.
$3$. $Use$ $of$ $surrogate$ $mothers$: The fertilized embryos are transferred to surrogate mothers for further development.
Therefore, all these methods are used in combination to improve the breed.

(C) In animal husbandry,continuous inbreeding leads to inbreeding depression,which reduces the fertility and productivity of animals. Outbreeding is the breeding of unrelated animals. It is the most effective method to overcome inbreeding depression and restore the fertility and vigor of the animals.

(D) Interspecific hybridization is a breeding method where male and female animals of two different related species are mated together.
This process allows the combination of desirable features from both parent species into the progeny.
An example of this is the mule,which is produced by crossing a male donkey and a female horse.

(D) Hisardale is a new breed of sheep developed in Punjab by crossing Bikaneri ewes and Marino rams.
Cross-breeding is a breeding technique in which a superior male of one breed is mated with a superior female of another breed.
This method allows the desirable qualities of two different breeds to be combined into a single progeny.

(D) Inbreeding refers to the mating of more closely related individuals within the same breed for $4-6$ generations.
$1$. Inbreeding increases homozygosity,which helps in the accumulation of superior genes and the elimination of less desirable genes (deleterious alleles).
$2$. It is essential for evolving a pureline in any animal.
$3$. However,continued inbreeding,especially close inbreeding,usually reduces fertility and productivity,a phenomenon known as inbreeding depression.
$4$. Inbreeding depression can be overcome by mating the selected animals with unrelated superior animals of the same breed,a process known as out-crossing.
Therefore,the statement that 'Inbreeding depression cannot be overcome by out-crossing' is incorrect.

(N/A) Animal breeding is an important aspect of animal husbandry.
$1$. The primary aim of animal breeding is to increase the yield of animals and improve the desirable qualities of the produce.
$2$. $A$ group of animals related by descent and similar in most characters like general appearance,features,size,and configuration are said to belong to a breed.
$3$. When breeding occurs between animals of the same breed,it is called inbreeding,while crosses between different breeds are called outbreeding.
$4$. Examples of improved breeds include:
$(a)$ Jersey (cattle breed)
$(b)$ Leghorn (chicken breed)

(N/A) Inbreeding refers to the mating of more closely related individuals within the same breed for $4-6$ generations.
The breeding strategy is as follows:
$1$. Superior males and superior females of the same breed are identified and mated in pairs.
$2$. The progeny obtained from such matings are evaluated for superior males and females.
- $A$ superior female,in the case of cattle,is the cow or buffalo that produces more milk per lactation.
- $A$ superior male is the bull which gives rise to superior progeny as compared to those of other males.
- Inbreeding increases homozygosity. It is necessary if we want to evolve a pureline in any animal.
- Inbreeding exposes harmful recessive genes that are eliminated by selection. It also helps in the accumulation of superior genes and the elimination of less desirable genes.
- Continued inbreeding,especially close inbreeding,usually reduces fertility and productivity,which is called inbreeding depression.
Outbreeding is the breeding of the unrelated animals,which may be between individuals of the same breed (but having no common ancestors for $4-6$ generations) or between different breeds (cross-breeding) or different species (interspecific hybridization). Outbreeding is the best breeding method for animals that are below average in productivity and growth rate.

(A) Controlled breeding experiments are carried out using artificial insemination.
For hybridization,semen is collected from the male that is chosen as a parent and injected into the reproductive tract of the selected female by the breeder.
The semen may be used immediately or can be frozen and used at a later date.
It can also be transported in a frozen form to where the female is housed. In this way,desirable matings are carried out.
Artificial insemination helps us overcome several problems of normal matings.
Often,the success rate of crossing mature male and female animals is fairly low even though artificial insemination is carried out.
To improve chances of successful production of hybrids,other means are also used.
Multiple Ovulation Embryo Transfer Technology $(MOET)$ is one such programme for herd improvement.
In this method,a cow is administered with hormones with $FSH$-like activity to induce follicular maturation and super ovulation.
Instead of one egg,which they normally yield per cycle,they produce $6-8$ eggs.
The animal is either mated with an elite bull or artificially inseminated. The fertilised eggs at $8-32$ cell stages are recovered non-surgically and transferred to surrogate mothers. The genetic mother is available for another round of super ovulation.
- This technology has been demonstrated for cattle,sheep,rabbits,buffaloes,mares,etc.
- High milk-yielding breeds of females and high-quality (lean meat with less lipid) meat-yielding bulls have been bred successfully to increase herd size in a short time.

(N/A) Inbreeding increases $homozygosity$.
Therefore,if we want to evolve a pure line in any animal,inbreeding is necessary.
Inbreeding exposes harmful recessive genes that are eliminated by selection.
This process helps in the accumulation of superior genes and the elimination of less desirable genes.

(A) The technology used to improve the success rate of fertilization and herd improvement is called $MOET$ (Multiple Ovulation Embryo Transfer).
During this procedure,a cow is administered hormones,such as those with $FSH$-like activity,to induce follicular maturation and superovulation.
Instead of one egg,$6-8$ eggs are produced per cycle.
The cow is then either mated with an elite bull or artificially inseminated.
Embryos at the $8-32$ celled stage are recovered non-surgically and transferred to surrogate mothers.
This technology has been successfully used for cattle,sheep,rabbits,and buffaloes.

(N/A) Modern breeding techniques significantly enhance food production. $A$ key example in animal husbandry is the Multiple Ovulation Embryo Transfer Technology $(MOET)$.
In this method,a cow is administered hormones with $FSH$-like activity to induce follicular maturation and superovulation. Instead of the single egg normally produced per cycle,the cow produces $6-8$ eggs.
The animal is then mated with an elite bull or artificially inseminated. The fertilized eggs at the $8-32$ cell stage are recovered non-surgically and transferred to surrogate mothers. This allows the genetic mother to be available for another round of superovulation.
This technology has been successfully applied to cattle,sheep,rabbits,buffaloes,and mares. It enables the rapid multiplication of high milk-yielding breeds and high-quality meat-yielding bulls,thereby increasing herd size in a short time and addressing food shortages.

(N/A)

Inbreeding	Outbreeding
$(1)$ Inbreeding refers to the mating of more closely related individuals within the same breed for $4-6$ generations.	$(1)$ Outbreeding refers to the mating of unrelated individuals,either within the same breed or between different breeds/species.
$(2)$ Inbreeding increases homozygosity.	$(2)$ Outbreeding increases heterozygosity.
$(3)$ Inbreeding is useful to evolve a pure line in any animal.	$(3)$ Outbreeding is useful to produce offspring with desired characteristics or to overcome inbreeding depression.
$(4)$ Continuous inbreeding usually results in inbreeding depression.	$(4)$ Outbreeding helps in eliminating inbreeding depression and restoring fertility and yield.

(A) Inbreeding is necessary to obtain a pure breed because it involves the mating of more closely related individuals within the same breed for $4-6$ generations.
Inbreeding increases homozygosity,which helps in the accumulation of superior genes and the elimination of less desirable genes.
Therefore,to develop a pure line or pure breed,inbreeding is a fundamental practice.

(D) The new breed of sheep,'Hisardale',was developed by crossing Bikaneri ewes and Marino rams. This method of mating animals of two different breeds is known as cross breeding. Cross breeding allows the desirable qualities of two different breeds to be combined into the progeny.

(C) Hisardale is a new breed of sheep developed in Punjab by crossing Bikaneri ewes and Marino rams.
This process,where superior males of one breed are mated with superior females of another breed,is known as cross-breeding.
Cross-breeding allows the desirable qualities of two different breeds to be combined into the progeny.

(A) The $Santa \text{ } Gertrudis$ is a breed of cattle developed through cross-breeding. It was created by crossing $Brahman$ bulls with $Shorthorn$ cows. This breed was developed in the $United \text{ } States$ to combine the heat and insect resistance of the $Brahman$ cattle with the superior beef production qualities of the $Shorthorn$ breed.

(C) Interspecific hybridization is a breeding method where males and females of two different related species are mated. The progeny obtained from such a cross may combine desirable features of both parents. $A$ common example is the mule,which is produced by the mating of a male donkey and a female horse.

(A) The mating of animals within the same breed,but having no common ancestors on either side of their pedigree up to $4-6$ generations,is known as $Out-crossing$. It is the best breeding method for animals that are below average in productivity in milk production or growth rate in beef cattle.

(A) Inbreeding depression is a phenomenon where continuous inbreeding,especially close inbreeding,reduces fertility and productivity in a population.
To overcome this,selected animals of the same breed that have no common ancestors on either side for $4-6$ generations should be mated with the breeding population.
This practice is known as $Outcrossing$.
It helps in restoring the genetic diversity and vigor of the population.

(B) In animal breeding,the selection of superior individuals is based on specific desirable traits. For dairy animals like cows,the primary objective is to increase productivity. Therefore,a superior cow is defined by its ability to produce a high yield of milk per lactation cycle. Other traits like body weight or physical appearance are secondary to the economic goal of milk production.

(D) Inbreeding refers to the mating of more closely related individuals within the same breed for $4-6$ generations.
Continued inbreeding, especially close inbreeding, usually reduces fertility and productivity.
This phenomenon is known as $Inbreeding \text{ } depression$.
It exposes harmful recessive genes that are eliminated by selection and helps in the accumulation of superior genes.

(C) Inbreeding refers to the mating of more closely related individuals within the same breed for $4-6$ generations.
It increases homozygosity,which is necessary if we want to evolve a pure line in any animal.
Inbreeding exposes harmful recessive genes that are eliminated by selection.
It also helps in the accumulation of superior genes and the elimination of less desirable genes.

(B) Inbreeding refers to the mating of more closely related individuals within the same breed for $4-6$ generations.
Outcrossing is the practice of mating animals within the same breed,but having no common ancestors on either side of their pedigree up to $4-6$ generations.
Both inbreeding and outcrossing involve mating between animals of the same breed.
Therefore,the common factor between them is that they both involve mating between individuals of the same breed.

(D) Cross-breeding is a method of animal breeding where superior males of one breed are mated with superior females of another breed. This allows the desirable qualities of two different breeds to be combined into the progeny. This method is specifically used to increase milk production capacity and meat growth rate in animals.