Easy Genetics for Dog Breeders E-Book

Jorge Santoianni

• Herausgeber: Editorial Autores de Argentina
• Kategorie: Lebensstil
• Sprache: Englisch

Seitenzahl: 106

Veröffentlichungsjahr: 2025

Beschreibung

Genetics are the basis of responsible breeding. In "Easy Genetics for Dog Breeders", Dr Jorge Santoianni offers a comprehensive and accessible guide for breeders interested in improving their bloodlines. This book covers everything from the basic principles of biology and genetics to advanced selection methods and breeding systems. With a practical approach and clear examples, it helps to understand how to manage genes to produce healthier dogs that conform to breed standards. Ideal for novice and experienced breeders looking for in-depth knowledge and applicable strategies.

Leseprobe

JORGE SANTOIANNI

Easy Genetics for Dog Breeders

Santoianni, JorgeEasy genetics for dog breeders / Jorge Santoianni. - 1a ed. - Ciudad Autónoma de Buenos Aires : Autores de Argentina, 2025.

Libro digital, EPUB

Archivo Digital: descarga y online

ISBN 978-987-87-6219-7

1. Adiestramiento. I. Título.CDD A860

EDITORIAL AUTORES DE [email protected]

Index

FOREWORD

INTRODUCTION

CHAPTER 1 - BASICS OF BIOLOGY

CHAPTER 2 - BASIC CONCEPTS OF GENETICS

CHAPTER 3 - QUALITATIVE INHERITANCE

CHAPTER 4 - GENETIC SEX DETERMINATION

CHAPTER 5 - QUANTITATIVE INHERITANCE

CHAPTER 6 - CONGENITAL DEFECTSAND GENETIC ABNORMALITIES

CHAPTER 7 - IMPORTANCE OF GENETICSIN DOG BREEDING

CHAPTER 8 - SELECTION

CHAPTER 9 - BREEDING SYSTEMS

CHAPTER 10 - THE MATERNAL GRAND-SIRE EFFECT

CHAPTER 11 - COAT COLOR GENETICSAND COAT TYPES

BIBLIOGRAPHY

To Emilio, who introduced me to the world of dog breeding and together we have been breeding Whippets since 1983. To my family, my friends and the responsible breeders in whose hands lies the future of dog breeds.

FOREWORD

The day our dear friend Jorge Santoianni asked us to write the foreword for his book Easy Genetics for Dog Breeders, we felt aware of the responsibility that comes with it, but doing so is a pleasure and a great honor for which we thank him.

We are breeders, exhibitors and judges just like Jorge, with an experience of more than 36 years, when doing a first reading of the draft of the book and after attending some of his seminars, our first thought was: “We wish in our beginnings could have received all the information that Jorge shares here”, we understand very well the importance and need of this book, since it is a synthesis of the Seminars that Jorge has been giving for years around the world, helping and training dog breeders, so we recommend reading and consulting it, both to those new breeders who are starting in the selective breeding of dog breeds and to those who have already been in it for some years.

Since we began breeding and selecting our dog breeds, we were clear about the importance of improving and selecting our future litters. That is why, from the very beginning, we have been checking and breeding healthy specimens free of the most common genetic diseases in our breeds, trying to develop a responsible and honest breeding program, with the ultimate goal of producing healthy and correct puppies, but which show “Superior Characteristics” while ensuring their soundness.

That is why and in our opinion, this book is a great Training Guide that is very necessary and of great help for every Dog Breeder, since it will provide Knowledge and Training, to, on the one hand, work and maintain healthy lines in selective breeding, and in turn know and be able to choose at all times the appropriate Selection Methods and Breeding Systems, without losing the objective of breeding specimens with superior characteristics and not simply breeding common specimens even though they may be healthy.

That is why, in our opinion, the part of the Art in selective breeding that the dog breeder must work on, health and morphology, studies of pedigrees of several generations, phenotype and genotype, etc., always go hand in hand, with the final objective of being able to get specimens with the essence of the breed and without losing their genetic pool.

From here, Jorge, we would like to thank you for your proposal and wish you the greatest success in this project that is so beneficial for anyone who is passionate about breeding, such as the Art of Selective Breeding.

Carmen Navarro and Rafael García

De Villaodon Samoyeds, Spain

INTRODUCTION

Anyone who wants to breed better dogs needs to have basic knowledge of genetics.

As breeders, we are all involved in “genetic experiments” every time we program a litter. For some breeders, determining which traits will appear in their puppies is like rolling the dice, a combination of luck and chance. For others, producing certain characteristics involves more skill than luck because it is the result of careful study and planning.

Both to understand how to manage genes in our breeding stock and to produce the class of dogs we want and to know why, we must have basic knowledge of genetics and know to apply it in dog breeding.

This book is aimed at those people who want to breed dogs, but do not have knowledge of a subject as complicated as Genetics. It was written in a simple way so that everyone can understand the how’s and whys of the decisions to be made when crossing two animals.

Breeders have tools that are: genetics, genetic anomalies, selection and breeding systems that we must understand to use them.

Before starting with genetics, we will start with basic notions of biology to understand the concept of a gene.

CHAPTER 1

BASICS OF BIOLOGY

The body of all living beings is made up of many millions of microscopic parts, called cells, which when joined together form tissues.

The cell is the morphological and physiological unit, that is the unit of form and function of every living being.

The cell is fundamentally made up of:

1- The cytoplasm is the cell body where the organelles with different functions are located: mitochondria are energy producers, ribosomes are involved in the synthesis of proteins together with the Golgi apparatus which is a reticular system that surrounds them, centrioles are involved in cell division, lysosomes related to digestion and others, all enveloped by the cell or cytoplasmic membrane.

2- The nucleus, enveloped by the nuclear membrane, is considered “the brain of the cell” where there is a ball of a very special substance called chromatin, which is DNA. (Deoxyribonucleic acid) that we inherit from our parents.

Let’s try to imagine the cell as a factory, where the nucleus is the management that gives all the orders of what should be done in the plant. (the cytoplasm).

There are different organelles there that perform different functions: mitochondria are energy plants, lysosomes are responsible for guarding everything that is imported and exported, ribosomes are like serial machines that manufacture products, Golgi apparatus wraps these products so that they can leave the cell, centrioles act in cell division, etc.

In the nucleus (management) there is a chemical molecule called DNA (deoxyribonucleic acid) which is directly responsible for all the orders given. This DNA is what we inherit 50 % from our father and 50 % from our mother.

During cell division, nuclear material or chromatin is organized and condensed to form chromosomes. These are mainly made up of DNA.

Each species has a specific number of chromosomes:

Man: 23 pairs or 46 chromosomes

Dog: 39 pairs or 78 chromosomes

Mosquito: 8 pairs or 16 chromosomes

KARYOTYPE OF A MALE CANINE

Although each dog has 39 pairs of chromosomes, only 38 are identical in shape to each other and are called autosomes. Pair 39 is called the sex pair and chromosomes are different.

In somatic cells, those that do not perform reproductive functions, we speak of the number of pairs of chromosomes or diploid number of chromosomes, while in sexual or gonadal cells they contain half the number of chromosomes , here we speak of haploid number of chromosomes.

MECHANISMS OF REPRODUCTION

Cell division

1- Simple: Mitosis

This is the process by which a cell divides into two daughter cells with the same number of chromosomes and identical to the mother cell. Mitosis occurs exclusively in somatic cells.

MITOSIS

Let’s take the example of a cell with two chromosomes. The first thing that happens is that each chromosome makes a replica of itself, giving a typical image of an “X”. In the second phase, the duplicated chromosomes line up in the center of the cell. Then they separate and move to opposite poles. Finally, the cell invaginates, giving rise to two identical cells with the same number of chromosomes as the parent cell.

All cells in the body (somatic cells) reproduce by mitosis, but here we must consider that 1 mother cell (doubles the number of chromosomes) gives rise to 2 daughter cells identical to it and with the same number of chromosomes. We lose epithelial cells permanently through desquamation, and yet we do not realize it because new cells replace them through the process of mitosis.

2- Sexual reproduction: Meiosis

It is the process by which a cell (diploid) divides into four daughter cells with half the number of chromosomes (haploid).

It occurs exclusively in sex cells.

A mother cell produces 4 daughter cells with half the number of chromosomes (eggs and sperm).

MEIOSIS

Let’s take an example of a cell with two chromosomes. Just as in mitosis chromosomes make a replica of themselves, once duplicated they separate and the cell invaginates and gives rise to two cells with one duplicate chromosome each.

Again, the chromosomes separate in each cell, these invaginate and give rise to 4 daughter cells with half the number of chromosomes of the mother cell.

Let’s look at something very important that happens in the first phase when the chromosomes make a replica of themselves, when the red and blue are duplicated, a phenomenon called crossing over occurs, where those who are closer exchange genetic material, and if we see the four chromosomes at the end of meiosis we see one all red, one red with a blue tip, a blue one with a red tip and a blue one. What is the importance of this?

This allows genetic variability, which means that not all siblings are the same, since they have different genetic material.

Spermatogenesis and oogenesis

In the male, it is the production of sperm and in the female, the production of eggs.

In the case of the human species, in the woman, of the 4 cells obtained in meiosis only one reaches a fertile egg while the remaining three transform into polar bodies (non-fertile), the same happens in cows and mares and that is why these species have one individual at a time. In dogs, when females perform meiosis, all the cells reach fertile eggs and, therefore, the litters are one or more individuals.

In sexual reproduction, the union of the egg with the sperm (both haploid) produces a diploid cell that contains half of the genetic material of each of the parents.

The new individual receives 50 % of the genetic material from the father and 50 % from the mother, therefore, it will be similar, but not identical to either of its parents.

CHAPTER 2

BASIC CONCEPTS OF GENETICS

Protein synthesis and Gene concept

We will try to explain the concept of gene in a simple way. The DNA “the boss” never leaves the nucleus, to give the orders it does so by means of another chemical molecule called messenger RNA (ribonucleic acid), this can leave the nucleus and go to the cytoplasm, there it makes the different organelles carry out with the orders of the DNA, for example synthesis of proteins.

Ribosomes act as serial knitting machines next to each other, let’s imagine that the DNA order is to knit a scarf of certain colors and another order another scarf of other colors and so on. Translated into biological terms, wool strands are amino acids and the union of them results in a protein.

Proteins are made up of amino acids found in the cytoplasm that will join together to form a specific protein as indicated by the DNA.

Proteins can have structural functions such as being part of hairs, horns, etc. and this is simple to understand, but the most important function is enzymatic, acting as catalysts or accelerators of chemicals reactions.

For a substance A to be transformed into B it can only do so if the enzyme is present. A and B are different, therefore, an individual that contains A will be different from another that contains B and this difference will be given only by the presence of an enzyme that was formed in the cytoplasm with the order given by the DNA and makes the reaction occur immediately.

Suppose substance A causes dark-colored eyes and B causes light-colored eyes. What determines whether an individual has dark or light eyes?

If the DNA has the order for the enzyme to be manufactured, A will automatically transform into B, if it does not have the order A it will not be transformed and will remain as A. Therefore, the color of an individual’s eyes will depend on if his DNA contains the order to manufacture an enzyme.

Therefore, we will say that a gene is the smallest portion of DNA that encodes (commands, orders) the synthesis of a protein.