Factors Affecting The Growth And Development Of Cattle Biology Essay
Modern cowss are posterities of Bos indicus and Bos Taurus ( Gillespie, 1992 ) . Harmonizing to Lawrie ( 1991 ) these strains are believed to be descended from Bos primigenius, the wild cowss. The last representative of the wild species died in Poland in 1627 ( Zeuner, 1963 ) . Lawrie ( 1991 ) reported that domestication of cowss followed the constitution of settled agribusiness about 5000 B.
C. and domestication of hump-back cowss ( Bos indicus ) existed in Mesopotamia by 4500 B.C.Garner ( 1944 ) stated that the immediate predecessor of bulk of the strains of British cowss was Bos longifrons, which was of comparatively little frame instead than Bos primigenius which is monolithic in size. The development of many present British strains was due to the early betterments initiated by Bakewell in the center of the 18th century, who introduced in-breeding, the usage of proved sires, choice and culling ( Lawrie, 1991 ) . Since 1790, the focal point on cattle betterment is towards smaller, younger and leaner animate beings ; and there has been turning realisation that strain potencies will non be to the full manifested without equal nutrient given at the right clip in the growing form of the animate being ( Hammond, 1932a ) .Lawrie ( 1991 ) suggested that a beef animate being should be good covered with flesh, blockish and compact-thus cut downing the proportion of bone whereas in a dairy animal the frame should be angular with comparatively small flesh screen, the organic structure should be cylindrical therefore suiting the big digestive piece of land necessary for efficient transition of nutrient into milk and mammary tissue should be markedly developed. Aberdeen Angus has been regarded as the premier strain for good-quality meat ( Gerrard, 1951 ) .
Lawrie ( 1991 ) reported that one of the grounds for the good feeding quality of the Aberdeen Angus is its tenderness which is due to the little size of the musculus packages, smaller animate beings holding smaller packages. Good-quality meat can besides be attained by feeding dressed ores such as barley to gripe cowss ( Preston et al. , 1963 ) .Attempts have been made to traverse assorted strains of Bos indicus ( Zebu cowss ) with British strains, to unite the heat defying belongingss of the former with the meat-producing features of the latter ( Lawrie, 1991 ) .Unfortunately, unusual strains of cowss are found within a normal strain: midget ”Snorter ” cowss occur within assorted strains in U.S.
A. , and pronounced muscular hypertrophy, which is frequently more noticeable in the hind quarters and explains the name ”doppelender ” given to the status, arises in several strains e.g.
Charollais and South Devon ( McKellar, 1960 ) . Recessionary cistrons are thought to be responsible in both instances ( Lawrie, 1991 ) .
2.2 FACTORS AFFECTING THE GROWTH AND DEVELOPMENT OF CATTLE
Lawrie ( 1991 ) reported that as an carnal grows two things happen: foremost, it increases in weight until mature size is reached ; this is called growing and secondly it changes in its organic structure conformation, forms and its assorted maps and modules come into full being ; this is referred to as development.
2.2.
1 Familial factors
Harmonizing to Lawrie ( 1991 ) several economically of import traits in meat animate beings are heritable to some grade and can therefore be selected for by engendering. In cowss, certain growing characteristics are controlled by recessive cistrons which have non so far been controlled, perplexing genteelness. One such trait is nanism ; another is the doppelender or “ dual muscling ” status, which causes musculus hypertrophy and thereby increases the animate being ‘s commercial value ( Lawrie and Ledward, 2006 ) . Familial analysis continues to uncover the familial mechanisms that control legion facets of the hormone system and, through it, meat growing and quality as concluded by Lawrie and Ledward ( 2006 ) .Familial technology techniques can shorten engendering programmes significantly because they allow for the designation and isolation of cistrons coding for coveted traits, and for the reincorporation of these cistrons into the carnal genome as reported by Lawrie and Ledward. Experimental generative cloning of commercially of import meat animate beings such as sheep, hog or cows has been successful. The multiple nonsexual reproductions of animate beings bearing desirable traits can therefore be anticipated, although this is non yet practical on a commercial graduated table.
2.
2.1 Environmental Factors
Heat ordinance in farm animal particularly cattle is of great economic significance, because mammals attempt to keep a changeless optimal organic structure temperature ( Lawrie and Ledward, 2006 ) . Low temperatures tend to protract carnal development and high temperatures tend to retard it.
Depending on their size, organic structure form and insularity through tissue and pelt, some animate beings have a comparatively narrow zone of temperature tolerance and others ( e.g. cowss ) a wide 1. Inactive magnetic Fieldss, for grounds still unknown, besides retard carnal development.
2.2.2 Nutritional Factors
Acker and Cunningham ( 1991 ) reported that the quality and measure of useable meat depends on the animate being ‘s plane of nutrition, i.e. , whether it is over or ill-fed. The composing of the diet, particularly the sum of protein provided, is besides an of import factor modulating carnal growing and development ( Wardlaw, 2000 ) . Cattle digest cellulose which is better adapted to poor-quality diets, but their ruminal micro-organisms degrade high-quality protein if supplied in surplus, because bring forthing high-quality protein carnal provender is expensive.Several techniques are employed or experimented with to guarantee maximal use of protein.
These include the intervention of provender with formol to protect aminic acids during their transition through the first stomachs, the recycling of manure by feeding it back to cattle assorted with provender dressed ores, or the partial transition of crude oil hydrocarbons to protein through microbic action ( Gillespie, 1998 ) .In works provender, environmental factors influence the handiness of important foods or micronutrients, a deficiency or surplus of which can do a great many complaints. In Australia, for case, where the dirt contains limited phosphate, cowss are being fed extra phosphate to increase the efficiency of beef production. Besides in Australia, cowss and sheep in certain countries were frequently found losing their appetency and death in the thick of rich grazing land ; this was at length found to be a consequence of Co lack in the soi ( Acker and Cunningham, 1991 ) .
Gillespie ( 1998 ) stated that works toxins are besides a hazard to croping animate beings ; for case, fluoracetate, found in some African and Australian workss, putting to deaths by interrupting the cellular metamorphosis. Certain semisynthetic pollutants such as methyl quicksilver and some pesticide residues present a peculiar jeopardy due to their inclination to bioaccumulate in meat, potentially poisoning consumers.
2.3 SLAUGHTERING AND KILLING OF CATTLE
2.3.1 Butchering
2.3.
1.1 Religious butchering
The Welfare of Animals ( Slaughter or Killing ) Regulations 1995 ( as amended ) ( WASK ) require that all animate beings are stunned before slaughter, utilizing the methods of stupefying prescribed by the Regulations, capable to specific freedoms. One of these freedoms refers to butcher without the imposition of unneeded agony by the Judaic method for the nutrient of Jews ; or by the Muslim method for the nutrient of Muslims, provided the demands for the licensing of slaughter work forces under the Regulations are met. Since a complete bleed is necessary, cowss are non stunned before hemorrhage ( Donin, 1972 ) .Religious issues environing slaughter without pre-stunning were explored in item in the FAWC study on spiritual slaughter published in 1985 and have non been reiterated in this study. Council has taken history of relevant information generated since so in pulling its decisions.
2.3.1.1.1 Judaic method
The Judaic method of butchering animate beings for nutrient ( Shechita ) requires that they be healthy at the clip of slaughter and must non hold suffered any physical hurt.
For this ground, pre-slaughter stupefying methods that are judged to do physical hurts prior to cutting the pharynx have been considered unacceptable for this slaughter method. Cattle are restrained in an unsloped place in a specialised pen with the caput held fast and the cervix exposed in a suited place for scratch of the pharynx.A transverse cut is made utilizing a mutual, uninterrupted gesture of the knife.
The purpose is to bring forth an immediate spring of blood by break uping both jugular venas and both carotid arterias. The knife used for cowss has a long, highly crisp and undamaged blade. After the cut has been made the animate being must stay reticent until it is bled out before being released, shackled and hoisted. With Rabbinical blessing some premises have adopted a post-cut stun for cowss.
2.3.
1.1.2 The Islamic method
The Muslim method of slaughter ( Halal ) is, in many respects, similar to Shechita. However, pre-slaughter stunning methods for cowss and sheep that have been demonstrated non to kill the animate being, such that the bosom is still crushing, have been deemed acceptable and have routinely been adopted in many Halal abattoirs.
The degree of restraint required to expose the pharynx, execute an effectual cut and keep the animate being still until it has bled out is greater than is needed for conventional slaughter.The restraining pens used for this purpose require Ministerial blessing. This is designed to protect bovine animate beings from any evitable hurting, agony, agitation, hurts or bruises in the pen and in peculiar to guarantee effectual agencies of restraint and support ” ( WASK ) . The design and operation of keeping pens are assessed by the SVS before Ministerial blessing is given.
2.3.
1.2 Humane slaughtering
Cattles are slaughtered by being first stunned and so exsanguinated ( bled out ) . Death consequences from the one or the other process, depending on the methods employed.
Stuning can be effected through smothering the animate beings with C dioxide, hiting them with a gun or a confined bolt handgun, or flooring them with electric current as reported by Lawrie and Ledward ( 2006 ) .Harmonizing to Lawrie ( 1991 ) run outing every bit much blood as possible from the carcase is necessary because blood causes the meat to hold an unsympathetic visual aspect and is a really good genteelness land for micro-organism. The exsanguination is accomplished by break uping the carotid arteria and the jugular vena in cowss and sheep, and the anterior vein cava in hogs.
2.3.2 Bleeding
Harmonizing to Beinempaka et al. , ( 1990 ) the cervix of the animate being is cut and it is allowed to shed blood by lifting it up. They besides reported that equal hemorrhage is indispensable to cut down meat spoilage since blood is a good beginning of wet and nutrition for most of the contaminating beings.
This indicates that the sum of blood retained in the beef determines the grade of spoilage of the beef. Panda, ( 1986 ) reported that the sum of blood drained out from different types of birds vary depending on the arresting technique and physiological status of the cowss.
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3.3 Deskinning and dressing
This procedure of deskinning is done manually or mechanical and manual at the same clip. The mechanical and manual 1s are usually done at the butchery. This involves utilizing a crisp knife to deskin the animate being while the machine pulls the tegument off the animate being.
Dressing involves the gap of the carcase to take the internal variety meats ( Beinempaka et al. , 1990 ) . Care must be taken in taking the bowels, as an unwilled scratch may ensue in the distribution of faecal bacteriums onto carcase perchance polluting the beef ( Borch and Arinder, 2002 ) .
2.3.
4 Washing
Following the deskinning and dressing phase is the washing phase. It involves utilizing a watercourse of H2O which removes soil and the sum of blood retained in the carcase. This helps in cut downing microbic burden nowadays on the carcase.
2.3.5 Chilling
This is done instantly after the readying of the carcase and must last for as short a clip as possible to avoid bacterial proliferation ( Gracey, 1986 ) .
Nester et al. , ( 2001 ) stated that chilling inhibits the growing of microorganisms such as Escherichia coli and Salmonella spp at temperature below 3-50C. Chilling in a common bath may ensue in cross-contamination from Escherichia and Salmonella bearers to free carcases ( Cross et al.
, 1988 ) .
2.4 NUTRITIVE VALUE OF BEEF
The usage of thin and clean beef is advisable to include in diet, it could be as an ingredient in frets or traditional formulas. Beef is a popular meat rich in protein, being a ruddy meat had ever made it a bad nutrient when it comes to surveies and researches ( Owen et al.
, 2005 ) . Wardlaw, ( 2000 ) stated that, a thin beef adds to wellness benefits related to bosom and bar of malignant neoplastic disease. As a affair of fact, no 1 can deny that beef is an of import beginning of protein.Beef is found to be really rich in Iron, Zinc, Selenium, Phosphorus, Potassium and Magnesium.
Sodium and Copper are found in good measures. However, infinitesimal measures of Calcium and Manganese are besides present. Harmonizing to Acker and Cunningham ( 1991 ) , beef is one of the best beginnings for Vitamin B12, Vitamin B6 Niacin and Riboflavin. However, it is besides rich in Thiamin and Pantothenic Acid. Small sums of Vitamin E, Vitamin K and Foliate are present.Harmonizing to Owen et al.
, ( 2005 ) the Calorie count of Beef per 100 gram is 155.0 ; it is meat which is higher in protein and chair in fat. Beef is good for castanetss and dentitions. It enhances unsusceptibility against infections of ear etc. , and prevents blood vas walls from damaging. Moderate ingestion of thin beef is wholly good for cardiovascular wellness and to forestall malignant neoplastic disease hazards.
The sum of fat in beef carcases has decreased compared to what it was during the center of the 20th century ; beef contains about 6 per centum less fat ( Gillespie, 1998 ) .
2.5 FRESHNESS OF DRESSED BEEF
Beef is a perishable merchandise and may do public wellness concerns. Fresh beef is most likely to botch before it will do food-borne diseases ( Gill, 1998 ) . For preserved meat the antonym may be the instance, where microorganisms have been eliminated.There is the inclination to utilize milder saving methods either because of energy economy, because of consumers ‘ penchant for mildly cured or cooked merchandises, or their desire for holding more fresh beef merchandises or because of an antipathy to the usage of preservatives ( Panda, 1995 ) .
Harmonizing to Lawrie and Ledward ( 2006 ) in order to fulfill these demands, it will be necessary for meat industry to better microbic monitoring of production including hygiene and to explicate procedures which will give minimum fluctuation in their consequences. Although intensive work is being carried out by meat industries to happen replacements for known procedures with tantamount inactivation or suppression of microbic foam, no overall acceptable option seems to be readily available ( Gracey, 1986 ) .
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6 QUALITY OF BEEF
The quality classs are based on the grade of marbling ( intramuscular fat ) in the beef, and the adulthood of the animate being at slaughter ( USDA, 2007 ) . A quality class is a composite rating of factors that affect palatableness of meat ; tenderness, succulence, and spirit. These factors include carcase adulthood, soundness, texture, and colour of thin, and the sum and distribution of marbling within the thin. Beef carcase quality scaling is based on grade of marbling and grade of adulthood ( Hale et al. , 2007 ) .
2.6.1 Texture
Meat from less stamp cuts or older cowss can be automatically tenderized by coercing little, crisp blades through the cuts to interrupt the proteins ( Denver, 2003 ) . Besides, solutions of exogenic proteolytic enzymes such as papain, bromelin or ficin can be injected to augment the endogenous enzymes ( USDA, 2007 ) . Similarly, solutions of salt and Na phosphates can be injected to soften and swell the myofibrillar proteins. This improves succulence and tenderness.
2.6.
2 Spirits
Vaporization concentrates the staying proteins and additions flavor strength ; the casts can lend a nut-like spirit. The bulk of the tenderising consequence occurs in the first 10 yearss, although two to three yearss allow important effects. Boxed beef, stored and distributed in vacuity packaging, is, in consequence, wet aged during distribution. Premium chophouses dry age for 21 to 28 yearss or wet age up to 45 yearss for maximal consequence on spirit and tenderness..
Salt can better the spirit, but phosphate can lend a soapy spirit.
2.7 SOURCES OF CONTAMINATION OF BEEF
Lawrie ( 1991 ) suggested that taint of beef is a go oning possibility from the minute of shed blooding until ingestion. Contamination of beef from the minute of shed blooding until ingestion is from microbic to physical taint. The microbiological taint of carcases occurs chiefly during processing and use, such as skinning, evisceration, storage and distribution at abattoirs and retail constitutions ( Gill, 1998 ; Abdalla et al. , 2009 ) .Faecal affair was a major beginning of taint and could make carcases through direct deposition, every bit good as by indirect contact through contaminated and clean carcases, equipment, workers, installings and air ( Borch and Arinder, 2002 ) .
Cattle slaughter operations, such as hemorrhage, dressing and evisceration, expose unfertile musculus to microbiological contaminations that were present on the tegument, the digestive piece of land and in the environment ( Gill and Jones, 1999 ; Bacon et al.,2000 ) .Furthermore, soiled workers custodies, apparels and equipments of the abattoir and at the market by retail merchants act as intermediate beginnings of taint of meat ( Gill, 1998 ; Gilmour et al. , 2004 ; AbdelSadig, 2006 ; Abdalla et al. , 2009 ) .Besides, managing and storage of beef contribute efficaciously to meat taint ( Beinempaka et al.
, 1990 ) . The storage topographic point should be clean and sooner cold ( 400F ) . Any temperature above will lend to microbic growing which act on the meat and cause spoilage whereas the beef must be handled with proper attention.
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8 METHODS OF MINIMIZING CONTAMINATION OF BEEF
Rangaswani ( 1983 ) reported that meat quality could be enhanced and prolonged when the causes of microbic taint are drastically reduced or removed wholly. He stated further that quality and wholesomeness of meat depend on many factors of which the followers are portion:
2.8.1 Beginning of Beef
Meat from butchery slaughtered animate beings and good established farms by and large have less bacteriums counts than meat from backyard slaughtered animate beings because at the butchery or farm, all the necessary safety and hygiene consideration are undertaken. The degree of infection is therefore minimized unlike backyard slaughtered animate beings where animate beings are killed and dressed on the floor with no better hygiene status ( Zeigler, 1966 ) .
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8.2 Health of Animals
Beef from healthy animate beings keep longer than beef from diseased cowss. This is so because beef from healthy animate beings are more likely to be free from any bugs unlike morbid cowss. Zeigler ( 1966 ) reported that veterinary review should be the precedence when animate beings are being slaughtered since it will be proven whether animate beings are free from any diseases.
2.8.
3 Method of Slaughter
Meat from bruised animate beings, improperly bled animate beings, meat contaminated with fecal matters during evisceration and meat soiled with soil from skin tends to botch early.The normal micro vegetation from the tegument of carcases includes Salmonella spp. , Staphylococcus aureus, and Escherichia coli and beings of faecal beginning ( Cross and Overby, 1988 ) .
The beginning of these beings is non clearly understood but in add-on to taint from the tegument and bowels, equipments and tools during slaughter and merchandising of beef may be responsible for some taint. To avoid farther taint, drinkable H2O should be used for rinsing carcases and surfaces coming into contact with meat and offal.
2.9 PRESERVATION OF BEEF
Harmonizing to Panda ( 1995 ) saving or meat can be done by following several techniques among which are infrigidation, desiccation, bring arounding, smoke, canning, irradiation, microwave warming and usage of chemical additives including antibiotics.
2.9.
1 Refrigeration
Refrigeration includes cold storage and frozen storage. In cold storage a temperature between 00C to 70C is employed and in frozen storage at between 150C to 170C ( Panda, 1995 ) . Controlled temperature aids in forestalling quality loss and keeping shelf life of the merchandise. Proper air circulation in add-on to care of air temperature prevents mould growing and controlled air composing provides fresh air and avoids development of immaterial smells out of unwanted gases.
Moisture control assists in forestalling inordinate desiccation of the merchandise stored ( Panda, 1986 ) .
2.9.2 Smoke
Smoking aid in continuing beef by moving as an antioxidant, disinfectant agent and supplying a protective covering on the surface. Smoking besides imparts specific spirit to meat.
Assorted types of wood used for bring forthing fume besides impart different spirit to the finished merchandise. However, the best type of wood which could be exploited for bring forthing quality smoked beef is difficult wood. Smoke besides influences the coloring material of the smoke-cured beef.
2.9.3 Bring arounding
This is a procedure of continuing meat. It is done to continue and keep ruddy coloring material of the meat and besides to add flavour. This ingredients used include common salt, Na nitrate or nitrite, sugar and spices ( Beinempaka et al. , 1990 ) . Therefore choice of bring arounding preparation is highly of import while utilizing it, every bit long as big sums of salt or spice will dissemble the spirit of meat. The maps of these bring arounding agents are different.
Salts aids in saving of meat while act uponing the spirit and texture. Sugar adds to the spirit while look intoing the drying and toughening consequence and nitrate provide the coveted pink coloring material to it ( Panda, 1995 ) .
2.9.4 Chemical Additives
Gill ( 1998 ) stated that fresh beef in integral carcase is non badly contaminated except for its surfaces and clambering. However, as it is minced for use in further processed merchandises, the solution alterations. As the beef gets exposed, added bacterial taint from custodies of operators and machineries used occurs ( Borch and Arinder, 2002 ) . Harmonizing to Panda ( 1995 ) the usage of additives in beef extends the life of the beef and has a small consequence on the coloring material, spirit and texture.
2.10 Packaging AND Storage
If the beef is to be used for processing, so it is taken directly to the meat film editing and industries to be processed. If they are to be stored for usage at a ulterior phase, these are decently packed in suited polyethylene bags and kept inside a deep freezing maintained at 15-180C. Panda ( 1995 ) reported that the packaging stuff used for boxing the beef should be colourless, transparent and of equal strength to safeguard the appareled beef packed during handling and transit.Besides, the packaging stuff should non reassign any harmful substances to the packed stuff.
The major aims in utilizing the packaging stuff is that it should supply optimal protection to the merchandise packed inside it and to keep wholesomeness for its anticipated shelf life, while forestalling physical, microbic and insect harm with appropriate belongingss and capacity to continue its alimentary value in an acceptable manner and other quality factors, of import in the selling channel ( Panda, 1995 ) .Assorted types of primary and secondary containers every bit good as flexible stuff are being used for packing beef merchandises. Primary container is one which is in direct contact with the nutrient point. The secondary container is the outer box or wrap that holds the primary units of nutrient such as jars, tins, Sns flexible bundles which have no direct contact with the nutrient point. Some of the assorted types of packaging stuff used for beef packaging include Sns, tins, glass, fictile movies and laminates.
