Đang tải... (xem toàn văn)
This course is designed to introduce students to basic concepts and principles of animal science and their application in animal agriculture. The objective of the course is to help the student to: Develop an overview of the nature of animals and animal production, Become familiar with terminology used in animal science as it relates to the industry, management practices, equipment and animals, Develop an understanding of animal species and breeds that compromise the livestock production and their relative importance from economic and social perspectives, Develop a basic understading of the value and contributions which animals can contribute to the human needs, Develop a basic understanding of animal genetics and breeding, animal nutrition, and reproduction, behaviour and welfare, Develop a basic understanding of current management practices as it relates to raising the common farm animal species, viz. swine, poultry, and cattle. The primary compensation for students taking this course is that they will
2013 INTRODUCTORY ANIMAL PRODUCTION LECTURE NOTES Nguyen Xuan Trach Nguyen Thi Tuyet Le Cu Thi Thien Thu HANOI UNIVERSITY OF AGRICULTURE TABLE OF CONTENTS INTRODUCTION Chapter THE SOCIO-ECONOMIC VALUE AND CONTRIBUTIONS OF ANIMALS 1.1 Basic concepts 1.1.1 Animals 1.1.2 Animal science 1.1.3 Animal production 1.2 The value of animals to mankind 1.2.1 Consumables (food) 1.2.2 Convertibles (materials) .8 1.2.3 Draught power 1.2.4 Other contributions 1.3 Animal production in food security and sustainable agriculture 11 1.3.1 Animal production and food security 11 1.3.2 Animal production and sustainable agriculture 11 Chapter ANIMAL GENETICS AND BREEDING 15 2.1 Fundamental principles of genetics 15 2.1.1 Transmission Genetics 15 2.1.2 Molecular Genetics 16 2.1.3 Population Genetics 17 2.2 Animal selection 19 2.2.1 Purpose of animal selection 19 2.2.2 Methods of animal selection 19 2.3 Breeding schemes 19 2.3.1 Purebreeding 19 2.3.2 Crossbreeding 21 Chapter ANIMAL REPRODUCTION 25 3.1 Reproductivion in mammalian animals 25 3.1.1 The reproductive systems 25 3.1.2 Reproductive processes 26 3.2 Reproduction in poultry 31 3.2.1 The reproductive system 31 3.2.2 Puberty 32 3.2.3 Breeding 32 3.4 Reproductive technology 33 3.4.1 Artificial insemination (AI) 33 3.3.2 Embryo transfer (ET) 34 Chapter ANIMAL NUTRITION AND FEEDING 36 4.1 Nutrients and their functions 36 4.1.1 Water 36 4.1.2 Protein 37 4.1.3 Carbohydrates 38 4.1.4 Fats 39 4.1.5 Minerals 39 4.1.6 Vitamins 40 4.2 Nutrient requirements 40 4.3 Feed 41 4.4 Ration and diet 42 4.5 Digestion and metabolism 43 4.5.1 Digestion 43 4.5.2 Metabolism 46 Chapter ANIMAL BEHAVIOUR AND WELFARE 47 5.1 Animal behaviour 47 5.1.1 Introduction to animal behaviour 47 5.1.2 Types of behaviour in farm animals 48 5.2 Animal wefare 52 5.2.1 Concepts of animal welfare 52 5.2.2 Assessment of animal welfare 53 5.2.3 Welfare of farm animals 55 Chapter ANIMAL HEALTH 57 6.1 Basic animal health concepts 57 6.1.1 Animal disease 57 6.1.2 Transmission of animal diseases 58 6.1.3 The immune system and immunity 59 6.2 Animal disease prevention 60 6.2.1 On-farm biosecuruty 60 6.2.2 Vaccination programs 61 6.2.3 Herd/flock health management 61 6.3 Animal disease control 62 6.3.1 Animal disease monitoring and surveillance 62 6.3.2 Treatment of diseased animals 63 6.3.3 Control of animal disease outbreaks 64 6.4 Socio-economic impacts of animal diseases 65 6.4.1 Animal diseases and human health 65 6.4.2 Animal health economics 66 Chapter SWINE PRODUCTION 68 7.1 Swine breeds 68 7.1.1 Local pig breeds of Vietnam 68 7.1.2 Exotic swine breeds 70 7.2 Swine production cycle and pork chain 72 7.2.1 Swine production cycle 72 7.2.2 Pork chain 74 7.3 Swine production systems 76 7.4.1 Farrow-to-finish systems 77 7.4.2 Farrow-to-feeder systems 78 7.4.3 Feeder-to-finish systems 78 Chapter POULTRY PRODUCTION 80 8.1 Types of chicken breeds 80 8.1.1 Egg laying chickens 80 8.1.2 Meat chickens 80 8.2 Production cycle of chicken farming systems 81 8.2.1 Breeder farm cycle 81 8.2.2 Layer farm cycle 83 8.2.3 Meat chicken farm cycle 84 8.3 The principles of poultry husbandry 86 8.3.1 Use of good quality and right class of stock 87 8.3.2 Provision of good housing 87 8.3.3 Maintanance of good health 88 8.3.4 Nutrition for economic performance 89 8.3.5 Good stockpersonship 90 8.3.6 Maximum use of management techiniqes 90 8.3.7 Use of records 91 8.3.8 Good marketing practice 91 Chapter BEEF CATTLE PRODUCTION 92 9.1 Beef cattle breeds 92 9.1.1 Temperate beef cattle breeds 92 9.1.2 Tropical beef cattle breeds 93 9.2 Beef cattle production cycle and beef chain 95 9.2.1 Beef cattle production cycle 95 9.2.2 Beef chain 96 9.3 Beef production systems 97 9.3.1 Extensive systems 97 9.3.2 Mixed farming systems 97 9.3.3 Intensive specialised systems 98 9.3.4 Beef cattle production systems in Vietnam 99 Chapter 10 DAIRY CATTLE PRODUCTION 101 10.1 Dairy cattle breeds 101 10.1.1 Temperate dairy cattle breeds 101 10.1.2 Tropical dairy cattle breeds 102 10.2 Dairy cattle production cycle and milk chain 102 10.2.1 Dairy cattle production cycle 102 10.2.2 Milk commodity chain 104 8.3 Dairy farming systems 107 8.3.1 General chracteristics of dairy farming systems 107 8.3.2 Types of dairy farming systems 107 INTRODUCTION This course is designed to introduce students to basic concepts and principles of animal science and their application in animal agriculture The objective of the course is to help the student to: Develop an overview of the nature of animals and animal production, Become familiar with terminology used in animal science as it relates to the industry, management practices, equipment and animals, Develop an understanding of animal species and breeds that compromise the livestock production and their relative importance from economic and social perspectives, Develop a basic understading of the value and contributions which animals can contribute to the human needs, Develop a basic understanding of animal genetics and breeding, animal nutrition, and reproduction, behaviour and welfare, Develop a basic understanding of current management practices as it relates to raising the common farm animal species, viz swine, poultry, and cattle The primary compensation for students taking this course is that they will have an invaluable knowledge of the basics of animal agriculture The knowledge attained and retained will not only help the student become better prepared for their professions, but also they will become wellinformed consumers for the remainder of their life Chapter THE SOCIO-ECONOMIC VALUE AND CONTRIBUTIONS OF ANIMALS Humans keep domesticated animals because they provide something of value Animal products provide one-sixth of human food energy and more than one-third of the protein on a global basis Animals make many additional contributions to the well-being of humans and the society Ultimately food supply and other aspects of quality of life for all people are very much dependent on animals This chapter is about basic concepts related to animals and their socio-economic contributions 1.1 Basic concepts 1.1.1 Animals Animals are a major group of multicellular, eukaryotic organisms of the kingdom Animalia or Metazoa Most animals are motile, meaning they can move spontaneously and independently Animals are also heterotrophs, meaning they must ingest other organisms for sustenance Herbivores eat plants; carnivores eat flesh; omnivores, such as humans, eat nearly everything Parasites inhabit and subsist in other organisms Animal evolution has resulted in a vast number of adaptations for successful life under all sorts of conditions, so that there are now more kinds of animals than of all other living things combined Livestock is a nebulous term and may be defined narrowly or broadly On a broader view, livestock refers to any breed or population of animal kept by humans for a useful, commercial purpose This can mean domestic animals, semi-domestic animals, or captive wild animals Semi-domesticated refers to animals which are only lightly domesticated or of disputed status These populations may also be in the process of domestication Some people may use the term livestock to refer just to domestic animals or even just to red meat animals The term as usually used does not include poultry or farmed fish; however the inclusion of these, especially poultry, within the meaning of 'livestock' is common 1.1.2 Animal science Animal science is described as "studying the biology of animals that are under the control of mankind" Historically the animals studied were farm animals but courses available now look at a far broader area to include companion animals for example dogs, cats, horses and captive animals The study of animal science is now concerned with the scientific understanding of how animals work: from the physiology and biochemistry of tissues and major organ systems down to the structure and function of biomolecules and cells Where particular emphasis is given to the study of growth, reproduction, nutrition and lactation of farm and companion animals and how these processes may be optimised to improve animal productivity, health and welfare 1.1.3 Animal production Animal husbandry, also called stockbreeding, is the agricultural practice of breeding and raising animals/livestock Raising animals is an important component of modern agriculture It has been practiced in many societies, since the transition to farming from hunter-gather lifestyles Farming practices vary dramatically worldwide and between types of animals Livestock are generally kept in an enclosure, are fed by human-provided feed and are intentionally bred, but some livestock are not enclosed, or are fed by access to natural feeds, or are allowed to breed freely, or any combination thereof Livestock raising historically was part of a nomadic or pastoral form of material culture The enclosure of livestock in pastures and barns is a relatively new development in the history of agriculture When cattle are enclosed, the type of ‘enclosure’ may vary from a small crate, a large fenced pasture or a paddock The type of feed may vary from natural growing grass, to highly sophisticated processed feed Animals are usually intentionally bred through artificial insemination or through supervised mating Indoor production systems are generally used only for pigs and poultry, as well as for veal cattle Indoor animals are generally farmed intensively, as large space requirements would make indoor farming unprofitable and impossible However, indoor farming systems are controversial due to: the waste they produce, odour problems, the potential for groundwater contamination and animal welfare concerns Other livestock are farmed outside, although the size of enclosure and level of supervision may vary In large open ranges animals may be only occasionally inspected or yarded in "round-ups" or a muster (livestock) Working dogs such as sheep dogs and cattle dogs may be used for mustering livestock as are cowboys, stockmen and jackaroos on horses, or with vehicles and also by helicopters Since the advent of barbed wire (in the 1870s) and electric fence technology, fencing pastures has become much more feasible and pasture management simplified Rotation of pasturage is a modern technique for improving nutrition and health while avoiding environmental damage to the land In some cases very large numbers of animals may be kept in indoor or outdoor feeding operations (on feedlots), where the animals' feed is processed, offsite or onsite, and stored on site then fed to the animals Animal production is the technology applied to the keeping of animals for profit It includes feeding, breeding, housing and marketing Industrial animal production is a modern form of intensive farming that refers to the industrialized production of livestock, including cattle, poultry (in "battery farms") and fish Most of the meat, dairy and eggs available in supermarkets are produced by industrialized agriculture Confined industrial animal agriculture of livestock and poultry are commonly referred to as factory farming and are criticised by opponents for the low level of animal welfare standards and associated pollution and health issues 1.2 The value of animals to mankind Humans keep domesticated animals because they provide something of value We can divide animal contributions to mankind into different categories as follows 1.2.1 Consumables (food) Livestock's most universal and significant productivity is in terms of milk, meat and/or eggs for direct consumption by the animal owners or for sale to others Diets based on meat, eggs and dairy products contain proteins, carbohydrates, fats, minerals and vitamins present in appropriate amounts and readily digestible forms to meet all human nutritional requirements Mammalian species such as cattle, pigs, goats, sheep, equines, yaks, cameloids, buffaloes, reindeer and poultry yield substantial consumable commodities The number of contributors becomes larger when exotic birds such as ostriches, guinea fowl, pheasants, quail, pigeons and Cornish hens are included and expands even further with poikilotherms such as fresh or salt water fish, shrimp, lobsters, crabs, oysters, mussels, squid, clams, scallops, frogs, turtles and even honey bees The total contributions from domesticated animals, while not approaching the proportions derived from plants, are still quite large, providing approximately 34% of human food protein and 16% of food energy supply 1.2.2 Convertibles (materials) Domesticated animals provide many materials used in manufacturing Wool and leather are the most abundant products but furs and silk are also important Although the world no longer relies on bone or ivory for buttons, other animal products such as feathers and pearls are still in demand for decoration Animal manure, although often referred to as a waste product in industrialized countries, is valuable for use as fuel, fertilizer or building material Many Asian and some African livestock owners mix cattle, buffalo, yak or camel dung with straw and dry this into convenient-sized cakes or blocks for use as a cooking or heating fuel In some regions dung is mixed with mud or clay forms building materials Animal manure can be placed in fermentation chambers to generate methane gas, which can be used as fuel for lighting, warming water, heating or even driving machinery such as water pumps Manure can also be a valuable source of feed for other animal species Poultry and pig manure can also be used to generate algae as a feed for fish Probably, the most universal and principal use for manure is as fertilizer Throughout the developing world, manure is the primary source of plant nutrients for traditional rainfed crops 1.2.3 Draught power Animals can be trained to perform a great variety of tasks, especially for draff power This is done by conditioning them – rewarding them for correct behaviour Cattle, buffaloes, horses, donkeys, mules, reindeer, yaks, elephants, dogs, camels and other cameloids all provide draft power for plowing, harvesting, transportation, lifting water and skidding logs Since the dawn of humanity, animals have been used for work, be it for agricultural production or for improving social status But over the past century, with increasing mechanisation, the animal work force has dwindled in developed countries, whereas they still contribute enormously towards fuel energy economy in most developing countries Although machines deriving energy from fossil fuels replaced draft animals in some regions, mechanization is too expensive or not suited to many cultivated terrains Thus, motive power will continue to be important throughout the developing world and might be revived to some extent even in industrialized countries 1.2.4 Other contributions Animals are also used by humans in a number of other ways: Recreation, warship and companionship Animals in sport, warship, companionship, ceremonies and leisure are all very important aspects of human association with animals However, none of these is free of ethical implication Much of the debate centres on the extent of the exploitation of animals Some people argue the specially bred animals enjoy what people get them to do, but others might say that the animals have no choice Fashion Throughout history, fur has been seen as a luxury item of clothing, conferring high status on its wearer Opponents of the fur trade have engaged in direct action for many years, and have had a high level of publicity This has meant that fur has become less fashionable since people’s awareness of animal welfare and conservation issues has been raised Health research There are three main types of scientific research in which animals can be used: “Pure” research: basic investigation into aspects of the biochemistry, physiology and anatomy usually of mammals for biomedical research Research into the causes and treatment of disease: investigation into pathological biochemistry, and physiology Testing of products for safety of use 9.2 Beef cattle production cycle and beef chain The beef commodity chain encompasses all segments from conception of the animal to the delivery of food to the consumer's table 9.2.1 Beef cattle production cycle The typical beef cattle production cycle can be described as in Figure 7.8 The typical beef cattle production cycle can be devided into three different phases: cow-calf, backgrounding and finishing Figure 7.8 The typical beef cattle production cycle Cow-calf phase Calves are born from cows and remain with their mothers for the first several months of life on farms or ranches As calves reach 6-10 months of age, they are weaned from their mothers After weaning, bull calves are typically castrated Weaned male calves (steers) may graze until about 95 one year old (yearlings) and then be sold to a cattle feeder or a stocker/backgrounder who will prepare the animal for the finishing/feedlot Genetically superior bull calves are separated out for use in breeding programs Heifers that will be kept in the herd reach sexual maturity by 15months of age and are bred to deliver their first calf when they are 24-months of age The gestation period for beef cattle is months Following the first calf, the female, now a cow, is rebred after a two to three month period and another calf delivered months later Stocker/backgrounding phase Once beef young stock have been weaned, rearing is carried out within a system that best suits the breed/genetic make-up of the animals From this age, the calves are usually fed on grassland Finishing phase One of the most important stages in beef production is gaining the desired ‘finish’ to the animal i.e the condition of the animal as it is presented at slaughter The correct finish will enable the animal to provide a beef carcase that meets the market specifications in terms of weight, conformation, fat class etc The diet in the latter stages of the production period (typically the last few months) has a profound effect on the eventual finish of an animal 9.2.2 Beef chain The beef chain involves the above beef cattle production phases and the following proccessing and marketing phases Packer phase (slaughtering and processing) Once cattle are considered “finished” they are transported to packing plants to be slaughtered and processed Precautions during transportation minimize stress and injury to the animals Cattle are carefully loaded and unloaded into trailers that are specially designed to avoid injury and strain When cattle arrive at packing plants, they are moved inside in a quiet and orderly manner There is little excess movement or unnecessary noise so cattle are not unduly stressed Packing plant technicians then use a mechanical stunning device to quickly and effectively render animals unconscious before slaughtering When beef leaves the packing plant, it is in the form of large sections, either primals, like the chuck, round rib and loin, or subprimals which are smaller cuts of meat such as the bottom round, top round, eye round and round tip Some plants sell subprimals to meat processing facilities where workers skillfully break them down into individual steaks and roasts that are sent to supermarkets and restaurants 96 Retailer phase (supermarkets and restaurants) Retailers and foodservice operators sell beef products in supermarkets and restaurants, where steps are taken to ensure the final safety and quality of the products Consumers Ultimately, consumers dictate the actions of the beef production chain, from pasture to plate, by determining what kinds of beef they will buy and at what price Beef producers read demand signals from the meat case and customers throughout the production chain For instance, beef cattle are now much leaner than just a decade ago as a result of the consumer demand for products with less fat 9.3 Beef production systems Beef production systems are classified according to the age at which animals emanating from a production unit are sold The production unit could be a farm or one of the enterprises in a larger undertaking A full description of a system includes the age, mass and carcass class at which animals are marketed, as well as the breeding, management and feeding practices followed There are many beef productions systems that are adopted by meat cattle farmers While in the developed countries production of quality beef is usually achieved through the feeding of highenergy rations to young animals (6 to 30 months old), the bulk of the beef produced in the developing countries still comes from rather extensive systems The main systems of production can be identified as follows 9.3.1 Extensive systems The breeding, raising, growing and finishing activities are operated by the same people on virtually the same grazings in extensive systems of beef production The animals stay in good condition for only 3–4 months of the year following the end of the rainy season On some extensive grazing-based farms, animals are mainly kept in fields and may be housed for part of the year In extensive systems the production costs, except those for watering the animals, are practically very low 9.3.2 Mixed farming systems In the past this was the traditional system of beef production in many parts of the world Small farmers kept young males and some culled heifers for feeding and finishing, and fed them on home-grown fodder Fattening and finishing of work oxen was also an important source of beef Under the mixed farming systems practised today, the feeder cattle are usually, but not always, produced on specialized breeding and raising farms located on poorer land or land unsuited to intensive farming 97 9.3.3 Intensive specialised systems Intensive systems of commercial beef cattle production may be divided into four general categories: (1) the cow-calf operations which produce weaned feeder calves for further grazing and/or feeding, (2) the backgrounding or stocker operations in which body weight is added to recently weaned calves, resulting in finishing-ready yearlings and (3) the finishing operations in which cattle are fattened for slaughter, and (4) various combinations of them The cow-calf system The cow-calf operation involves maintaining a breeding herd to produce the heaviest weight of weaned calves possible Breeding-herd size varies considerably, from a few cows on small mixed farms to several hundred in large range herds The average cow will stay productive in a breeding herd for to years if no disease or physical problems develop The female side of the breeding herd usually consists of cows and heifers of a single breed, or the female crosses of breeds that are likely to produce hybrid vigour in the various maternal characteristics such as milking and mothering ability Performance-tested, purebred bulls from breeds noted for their post-weaning growth and carcass characteristics make up the male side of the herd The cow-calf operation involves breeding of cows with bulls or artificial insemination, conception, gestation, birth of the calf and lactation periods until weaning of the calf from the cow Normally, when the calves reach 6-10 months of age, they are weaned from their mothers The stocker system The stocker operation is normally attached to the cow-calf or the finishing enterprises, being essentially a period of growth between weaning and the finishing phase for slaughter (6-12 months) It is roughage- and pasture-based, aimed at getting as much efficient youthful growth of skeleton and muscle as possible As a single enterprise, it is highly speculative and is usually a "grasser" operation for individuals with ample pasture but no winter feed These farmers buy wintered steer and heifer calves in spring, and then resell them in late summer or fall to feedlot operators The finishing system These are where animals are fed a diet to get them ready for slaughter While some cow-calf operators may carry out this enterprise after a stocker phase for their own calves, most finishing is now done in specially designed units, holding several hundred or thousands of animals Some farmers traditionally used the feedlot to enhance the value of their home-grown crops and to provide a winter occupation A feedlot or feedyard is a type of Confined Animal Feeding Operation (CAFO) (also known as "factory farming") which is used for finishing livestock, notably beef cattle, prior to slaughter They may contain thousands of animals in an array of pens 98 Stocker calves are placed in a confinement feedlot for approximately 90 to 120 days Feedlot diets are usually very dense in energy, to encourage the deposition of fat, or marbling, in the animal's muscles; Some consider this fat desirable as it leads to 'juiciness' in the resulting meat The animal may gain an additional 400 pounds (180 kg) during its 3-4 months in the feedlot Typical slaughter ages of beef cattle depeding on diet type, breed and sex: Diet Type Breed Type / Sex Intensive cereal beef Intensive grass silage beef Mixed grass/concentrate fed beef Mixed grass/concentrate fed beef Forage based suckler beef Continental & Dairy breeds / bulls Dairy cross & Beef breeds / bulls & steers Dairy cross / Steers & Heifer Dairy cross & beef / Steer Beef breeds / Steers and Heifers Age at Slaughter 12 months 16 months 18-20 months 22-26 months 18-20 months Combined systems There are various combinations of the above three phases of intensive beef cattle production in one farming system In such a combined system, in addition to the breeding herd to produce calves, the calves may be used in one of the following ways: - After weaning, bull calves are typically castrated (steers), let graze until about one year old (yearlings) and then sold to a cattle feeder or a stocker/backgrounder who will prepare the animal for the finishing/feedlot - Suckled bull calves are given creep feeding (supplying supplemental feed, usually concentrates) After weaning, they are kept with good feeding until 12-15 months of age and then sold to a finishing/feedlot operation - After weaning, bull calves are typically castrated (steers), let graze or pen fed and then fattened before slaughter at 18-24 months of age On some farms, depending on the availability of feed, weaned calves may be placed directly into a confinement feedlot for growing and finishing, skipping the grassland phase 9.3.4 Beef cattle production systems in Vietnam In Vietnam beef cattle production involves a number of different farming systems as follows: Extensive calf-cow grazing systems, under which grazing in the open is practiced in the daytime and penning is used at night The farmers operating these systems generally not feed their cattle mixed animal feed, whether made by the farmer or purchased from a commercial supplier The primary motivation of these farmers is generally wealth creation for their family, i.e they have an asset, e.g old cattle or a calf, that can be sold when they need money; 99 Intensive calf-cow systems, under which the cattle are in pens most of the time but may spend a few hours each day free or tethered grazing These farmers feed cultivated grass and also some locally made concentrate to their cattle The primary motivation of these farmers is the commercial sale of fattened cattle, weaned calves or yearlings; and, Cattle fattening systems, under which cattle are usually kept in pens all the time These farmers are commercially motivated, and much better funded than other cattle farmers They buy old and young cattle from both the intensive and extensive cattle farmers for fattening up The smallholder farmers involved in this activity usually feed their cattle with cultivated grass Larger operations tend to use cultivated grass and some concentrates Review excercises Describe the major features of a temperate beef cattle breed Describe the major features of a tropical beef cattle breed Describe the major features of the Yellow cattle Draw and explain a typical beef cattle production cycle What ware the three phases in a typical beef cattle production cycle? Describe a typical beef commodity chain What are the main chracteristics of a cow-calf operation? What are the main chracteristics of a finishing operation in beef cattle production? What are the main chracteristics of a combined beef cattle operation? 10 Describe beef cattle farming systems in Vietnam 100 Chapter 10 DAIRY CATTLE PRODUCTION Dairy farming has been part of agriculture for thousands of years, but historically, it was usually done on a small scale on mixed farms with the same stock often being used for both meat and milk production Today, dairy cows are specialized and most have been bred to produce large volumes of milk, with little or no regard for their production of meat In Vietnam dairy production had increased very fast recently.This chapter is a brief introduction the most commom dairy cattle brees, the milk production cycle, dairy production systems and the milk commodity chain as a whole 10.1 Dairy cattle breeds Dairy cattle are cattle raised for their ability to produce large quantities of milk Following are some major breeds of dairy cattle 10.1.1 Temperate dairy cattle breeds The Holstein Friesian (HF) The Holstein Friesian breed originated in Holland The breed is very famous all over the world and characterized by its colour (shiny black and white), large size and exceptional milk production Mature bulls weigh up to 1200 kg; mature cows up to 750 kg A mature cow annually produces an average of 8000 kg of 3.7% butter fat, 3.2% protein milk The Jersey The Jersey breed originated on the Island of Jersey, a small British island in the English Channel off the coast of France The Jersey is one of the oldest dairy breeds Jerseys are a fawn colour, except along the spine, around the muzzle and on the inside of the legs, where they are a paler shade Bulls are darker than cows and some strains produce offspring with white markings They are excellent grazers and perform well in intensive grazing programs They are more tolerant of heat than 101 the larger breeds With an average weight of 900 pounds, the Jersey produces more pounds of milk per pound of body weight than any other breed Most Jerseys produce far in excess of 13 times their bodyweight in milk each lactation The Brown Swiss The Brown Swiss breed originated in Europe, particularly Switzerland, and were brought to Canada in 1888 These cattle mate well with beef breeds Bulls weigh up to 1135 kg; cows, 700 kg Mature cows will annually produce about 6600 kg of 4.1% butterfat, 3.5% protein milk 10.1.2 Tropical dairy cattle breeds The Sahiwal The Sahiwal breed originated in the dry Punjab region which lies along the Indian-Pakistani border Due to their heat tolerance and high milk production they have been exported to other Asian countries as well as Africa and the Caribbean Their colour can range from reddish brown through to the more predominant red, with varying amounts of white on the neck, and the underline In males the colour darkens towards the extremities, such as the head, legs and tail It is tick-resistant, heat-tolerant and noted for its high resistance to parasites, both internal and external Cows average 2270kg of milk during a lactation while suckling a calf and much higher milk yields have been recorded They are generally docile and lethargic, making them more useful for slow work The Sahiwal is the heaviest milker of all Zebu breeds and display a well developed udder Sahiwals demonstrate the ability to sire small, fast-growing calves and are noted for their hardiness under unfavorable climatic conditions 10.2 Dairy cattle production cycle and milk chain 10.2.1 Dairy cattle production cycle The production of milk requires that the cow be in lactation, which is a result of the cow having given birth to a calf The cycle of insemination, pregnancy, parturition, and lactation, followed by a "dry" period before insemination can recur, requires a period of 12 to 16 months for each cow (Figure 10.6) 102 Figure 10.6 A typical dairy cattle production cycle Life for a cow starts as a calf or baby cow With a lot of intensive care the female calf is reared till it is able to cope on its own This usually takes about months At this time the calf is weaned or removed from milk and allowed to graze with the older animals As the young female calf grows she is called a Heifer or an unmated female cow From weaning, the heifer will take about 15 months to grow to a size at which she can be mated Cows have a gestation period of 280 days Therefore the pregnant heifer will normally have her first calf at an age of 27 months old Female calves (heifers) with dairy breeding may be kept as replacement cows for the dairy herd If a replacement cow turns out to be a substandard producer of milk, she then goes to market Before the calf is born the cow’s body begins to prepare for its birth by producing milk in the udder Soon after the calf is born it instinctively feels for the mother’s udder and suckles causing 103 the release of milk from the udder The first release milk or fresh milk is called colostrums and is different to the normal milk Colostrums is a special milk containing lots of vitamins, minerals, protein and energy, which provide the calf with life-boost and a protection against disease Once the colostrum milk has been fed to the new born calf, normal milk will begin to be formed in the udder The cow will than be milked and the milk collected and stored prior to being sent to the factory for processing Once a calf is born the cow will continue to give milk for about 300 days, which is termed the lactation period On average a cow may produce 5000 litres per lactation period, which is an average of 17 litres per day However, the amount of milk produced is not the same on every day, with more being produced at the start of lactation and less towards the end of lactation period About 60 days after calving the cow will be mated again so that she will have a calf to initiate milk production in months from mating or next lactation This will mean she should be back milking 360 days or a year after she first had a calf When the cow is about 300 days in milk she may only be producing – 10 litres per cow, at this point the cow is dried off and given a rest from milking for about months before calving again and the cycle continues Dairy cows may continue to be economically productive for many lactations Ten or more lactations are possible However, the chances of problems arising which may lead to a cow being culled are high 10.2.2 Milk commodity chain The milk commodity chain (from feed to food) can be divided into steps as follows: Step – Feeding cows Typically cows spend about hours eating, hours sleeping and hours ruminating or chewing their cud Cows are usually provided with a fresh paddock of grass in the morning after milking and another fresh paddock of grass in the evening after milking They may also be fed some concentrate feed in the dairy while being milked Many dairy farms also grow their own forage This is fed directly to the cows, or is stored as silage or hay (conserved forage) for use during the winter season when there is not enough grass available Additional dietary supplements containing protein, minerals and vitamins are added to the feed to increase quality milk production 104 Step - Harvesting milk Cows are normally milked times per day, however some high producing herds are milked times per day Normally cows are milked at about am in the morning and again at about pm in the evening Milking time takes about minutes per cow but depends on the type of milking and the amount of milk the cow is producing Milking may be made by hand or by machine Hand milking Until the late 1800s, the milking of the cow was done by hand When it became necessary to milk larger numbers of cows, the cows would be brought to a shed or barn that was set up with bails (stalls) Milking took place with the cattle tied by the neck with ropes or held in place by stanchions One person could milk more cows this way, as many as 20 for a skilled worker Feeding could occur simultaneously with milking in the barn, although most dairy cattle were pastured during the day between milkings Machine milking Most dairies have enough machines to milk 20 to 40 cows or more at one time, reducing the amount of time the cows wait to be milked Milking machines mimic the action of a young calf by creating a pulsating vacuum around the teat, which causes the milk to be released from the udder Innovation in milking focused on mechanising the milking parlour to maximise throughput of cows per operator, which streamlined the milking process to permit cows to be milked as if on an assembly line, and to reduce physical stresses on the farmer by putting the cows on a platform slightly above the person milking the cows to eliminate having to constantly bend over The milking parlor allowed a concentration of money into a small area, so that more technical monitoring and measuring equipment could be devoted to each milking station in the parlor Rather than simply milking into a common pipeline for example, the parlor can be equipped with fixed measurement systems that monitor milk volume and record milking statistics for each animal Tags on the animals allow the parlor system to automatically identify each animal as it enters the parlor Step - Storing milk Milk storage vats or silos are refrigerated and come in various shapes and sizes Milk is stored on farm at degrees Celsius and less for no longer than 48 hours Vats and silos are agitated to make sure that the entire volume remains cold and milk fat does not separate from the milk After milk has been collected, storage vats and stainless steel pipes are thoroughly cleaned before the farmer milks again 105 Step - Transporting milk Milk is collected from the farm every 24 or 48 hours The tankers that are used have a special stainless steel body which are heavily insulated to keep the milk cold during transportation to the processing factory Milk tanker drivers are accredited milk graders, which allows them to evaluate the milk prior to collection Tanker drivers grade and if necessary reject milk based on temperature, sight and smell A representative sample is collected from each farm pickup prior to being pumped onto the tanker After collection, milk is transported to factory sites and stored in refrigerated silos before being processing Step - Laboratory testing Samples of milk are taken from farm vats prior to collection and from the bulk milk tanker on arrival at the factory Samples from the bulk milk tanker are tested for antibiotic and temperature before the milk enters the factory processing area Farm milk samples are tested for milkfat/protein/bulk milk cell count and bacteria count If milk is unsuitable for our quality products the milk will be rejected Most farmers are paid on quality and composition of their milk and it is extremely important that these samples are collected and stored correctly Step - Processing milk Whole milk, once approved for use, is pumped into storage silos where it undergoes pasteurization, homogenization and further processing Pasteurization: Involves heating every particle of milk to a specific temperature for a specified period of time and cooling it again without allowing recontamination Pasteurization is performed for two reasons; Ensure all milk products are safe for human consumption by destroying all bacteria that may be harmful to health (pathogens) Improve the keeping quality of milk by killing or inactivating some undesirable enzymes and spoilage bacteria Homogenisation: Involves pushing the raw milk through an atomizer to form tiny particles so that the fat is dispersed evenly throughout the milk, stopping the fat from floating to the top of the container Further processing: Includes, reducing the fat content by micro-filtration, increasing the storage life by ultra high temperature (UHT) treatment and mixing or culturing milk for flavored and yoghurt products Step - Selling milk 106 Then milk is sent off to stores for sale to the general public 8.3 Dairy farming systems 8.3.1 General chracteristics of dairy farming systems Dairy farming is a class of agricultural, or an animal husbandry, enterprise, for long-term production of milk, usually from dairy cows but also from goats, sheep and camels, which may be either processed on-site or transported to a dairy factory for processing and eventual retail sale Dairy operations include both the production of milk and the production of calves Most dairy farms sell the male calves born by their cows, usually for veal production, or breeding depending on quality of the bull calf, rather than raising non-milk-producing stock Many dairy farms also grow their own feed, typically including corn, and hay This is fed directly to the cows, or is stored as silage for use during the winter season or for making total mixed ration (TMR) for the whole year round Dairy production systems in developing countries may be identified by a combination of characteristics These include buffalo or cows; small versus medium versus large units; mixed farming versus specialised dairy units; urban or rural-based production; public versus private sector participation in production, processing, procurement and distribution; breed improvement versus feed improvement; upgrading existing breeds or developing synthetic breeds; dual purpose or single purpose breeds; and decisions to focus development efforts on high-potential areas for dairying versus a diffusion strategy to reach the maximum number of current or potential producers Reproduction is important in the life cycle considerations of a dairy, because the cow must "calve" or produce an offspring to "freshen" or to begin lactation and produce milk Cows are simultaneously in various life cycle stages in the same "typical" dairy 8.3.2 Types of dairy farming systems There are a number of different types of dairy farming system in the world as well as in Vietnam with each one selected to suit the local conditions, the breed of cow and the size of the herd Dairy farming systems range from large-scale, intensive, vertically integrated commercial systems to smallholder `subsistence-plus' income systems Grass-based systems This is typical of what the general public might consider to be a “traditional way of farming” Most dairy herds graze during the spring and summer months, and be housed for up to six months of the year, usually from late autumn through to the end of winter, when the weather is 107 cold and grass stops growing This practice can vary depending on weather conditions, availability of feed and stage of lactation In extreme weather conditions farmers may decide to house their herds to allow for better care and attention, especially when grass growth is minimal, feed availability is low and the impact of heat stress is high Housed systems In the world, most milk is produced by cows raised in intensive production systems These include tie stall barns, free stall barns, and open lots Dairy herds may spend the majority of their time indoors in modern, well ventilated and light cattle sheds This is referred to as ‘continuous’, or ‘year round’ housing In some cases, these cows may spend up to three months outdoors during their dry period (the three months before a cow gives birth to a calf), and may have access to pasture for exercise and to socialise Within these systems each cow is required to have space to move around, a bed to lie in and sufficient space to feed It is common in housed units for farmers to also provide loafing areas, cow grooming brushes, fans and water sprinklers to ensure maximum cow comfort Cows that are predominantly housed indoors are fed a diet of freshly cut pasture or silage and mixed ration feed to ensure that all their nutritional requirements are met The more intensively managed systems feed cows rations that are relatively high in concentrates and stored forages In recent years there has been a gradual increase in the number of farmers adopting year round housing systems This is due to a number of factors, which include the reported health and welfare benefits of being able to provide a consistent feed ration to cows (particularly those with higher milk yields), the increased uptake of robotic milking systems, and, in some cases, an increase in herd size Mixed systems Some producers use a combination of the two above systems, which is appealing in that it reduces costs, but still allows the feeding of concentrate to improve milk production levels Extensively grazed systems An extensively grazed, or ‘New Zealand’ style system, is one where the cows spend the majority of the year outdoors and are likely be out wintered in all weather conditions This style of farming is commonplace in the southern hemisphere but not widespread in the North due to the cold winter weather conditions It is generally suited to areas where there is adequate rainfall and soil temperature to ensure prolonged grass growth and for lower yielding cows During the winter months, when grass stops growing, cows will be fed a supplementary diet of forage on feed pads (areas of hard standing) In the countries that practice this system herds tend to be block spring calved, and milk production is low during the winter period These pasture-based 108 systems often strive to optimize rather than maximize milk production while paying careful attention to controlling input costs Smallholder systems Smallholder dairy production is common in many parts of the developing world, providing an important source of nutrition and income to millions of households Smallholder dairying is invariably part of a larger and more complex farming system that typically includes farmproduced inputs such as feeds, various off-farm inputs, family inputs of labour and management and outputs of various types Smallholder dairy production takes many forms and is often combined with cottage industry (small household) processing activities Smallholder dairy production is mostly carried out by the family, with some very limited hired labor Examples of smallholder dairy production are the mixed farms in Central America with 25 cattle; small mixed farms in the highlands of Ethiopia with one or two cows; rice farms in the Punjab of India with 10 buffaloes Review excercises Describe the main features of a dairy cattle breed Draw and briefly explain the typical dairy cattle production cycle Elaborate on the life cycle of a dairy cow Draw a lactation curve and elaborate on it Describe the milk commodity chain Elaborate on the types of feed the dairy cow is normally fed Elaborate on how a cow is milked Elaborate on how milk is stored and transported Explain why and when milk is tested 10 Describe how milk is processed and marketed 109 ... and animals in resource-conserving systems Review excercises Define animals, livestock, animal science, animal husbandry, animal production Develop a modest understanding of contributions of animals... contributions 1.3 Animal production in food security and sustainable agriculture 11 1.3.1 Animal production and food security 11 1.3.2 Animal production and sustainable... growth, reproduction, nutrition and lactation of farm and companion animals and how these processes may be optimised to improve animal productivity, health and welfare 1.1.3 Animal production Animal