Beef Cattle

A.D. Herring , in Encyclopedia of Agronomics and Nutrient Systems, 2014

Summary

Beef cattle are very useful in a wide range of production environments globally to supply a broad array of products. The weight and amount of muscle in beef cattle are important in many cultures. In some cases, information technology is the older animals that are utilized for beef subsequently they have been utilized for draft purposes; however, it has been the supposition throughout this article that product of cattle for beef carcass markets is a primary goal. This article has not discussed many specific considerations involved in beef cattle production simply has attempted to point out unique aspects of beef cattle production that might be unlike in other livestock species. Full general principles for breeding, genetics, nutrition, reproduction, health, and welfare are like beyond livestock species, simply specific knowledge and management within each species (likewise every bit within combinations of animal resource, production surround, and local markets) are crucial for short-term also as long-term economic success.

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Female Reproduction

Niamh Forde , in Encyclopedia of Reproduction (Second Edition), 2018

Introduction

Beefiness cattle breeds are mono-ovulatory and polyestrus in nature and tend to have a defined estrous cycle length of approximately 21 days. Female reproduction begins when a beefiness heifer begins to cycle on a regular basis and normally coincides with the heifer reaching fifty% of its adult weight at approximately 12–15 months of historic period. The estrous cycle is regulated in a similar manner to other mono-ovulatory species with the training of the uterus for successful pregnancy irrespective of whether or not an embryo is nowadays. The embryo undergoes a period of rapid elongation of the trophectoderm cells, and maternal recognition of pregnancy is required in club for the corpus luteum (generated past restructuring of the cells from the ovulated follicle) and progesterone concentrations in circulation to exist maintained. Placental germination in beef cattle is cotyledonary in nature and quite superficial with pregnancy lasting between 279–287 days depending on brood and sex of the foetus. Parturition is similar every bit in dairy cattle, but beefiness cattle do not feel the post-partum negative energy balance that dairy cows exercise and take comparative ease to go pregnant once more. Specialist breeds of beef cattle are adapted to agin weather condition, due east.g., tropical climates, which have led to some interesting reproductive functions. These comparative differences in female person beef cattle reproduction will be explored in greater depth in the sections below (meet Table 1 for a summary).

Table 1. Comparison of major reproductive events of female person cattle compared to different model and domestic species

Cattle (Bovine) Sheep (Ovine) Pig (Porcine) Mouse (Murine) Human being
Ovulation blazon Spontaneous Seasonal Continual Spontaneous Spontaneous
Ovulation number Mono-ovulatory Mono-ovulatory (mainly) Poly-ovulatory Poly-ovulatory Mono-ovulatory
Embryonic genome activation eight–16 cell stage viii–16 cell stage 4–viii cell stage two-cell stage four–8 cell stage
Completion of X-Chromosome inactivation Post-blastocyst Mayhap blastocyst Post-blastocyst Blastocyst Blastocyst
Elongation rate Rapid Rapid Extremely rapid North/A N/A
Pregnancy recognition signal Bovine Ovine Estrogens Prolactin Man chorionic gonadotrophin
Interferon Tau Interferon Tau
Placentation Cotyledonary Cotyledonary Diffuse Discoid Discoid
Synepitheliochoriol Synepitheliochoriol Epitheliochoriol Haemochorioal Haemochorioal
Duration of gestation (Days) 279–292 142–152 114 21 280

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Diet, feeding and management of beefiness cattle in intensive and extensive production systems

Tim A. McAllister , ... Gabriel Ribeiro , in Animal Agriculture, 2020

Determination

Beef cattle are unique, compared to poultry and swine in that they can convert low-quality forages into loftier-quality protein for humans. Recently, there has been growing pressure level to globally restrict beef production, due to its perceived negative bear upon on the surround. Beefiness cattle play a significant role in the production of food for humans, from forages and vast tracks of both tame and native pasturelands. In native grasslands, beef cattle largely supplant the role of the bison that previously occupied this ecosystem. Care must be taken to ensure that the nutritional needs of beefiness cattle are aligned with the productivity of the pasture, so equally to avert detrimental impacts on both the animal and the ecosystem. Global appetite for beef is projected to increase and in low-cal of the emerging pressures of climate change and the scarcity of new tracts of pasture and arable country, sustainable intensification will be the only means of satisfying demand. Intensified systems volition need to increase the use of by-product feeds and nutrient wastes in beef cattle production. Nutrient management plans will be needed to ensure that nutrient flows are aligned with the principals of a round bioeconomy. Finally, advanced technologies that improve the efficiency of feed utilization with an emphasis on both the plant and the animal will need to gain societal acceptance if more than beef is to exist produced on less land. 93 , 95

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Methods to measure body limerick of domestic animals

Steven Yard. Lonergan , ... Dennis Northward. Marple , in The Science of Animal Growth and Meat Technology (Second Edition), 2019

Backfat probe for cattle

Beef cattle must be restrained before the fat-probing procedure is started. In cattle, the fat thickness probe is placed through the skin approximately 5  in. from the midline between the 12th and 13th ribs. A modified needle probe is unremarkably used in beef cattle rather than a modest ruler that is used in pigs (Fig. 8.15). The needle probe is more constructive for penetrating the thick pare of beef cattle and consists of a thick stainless steel wire attached to a metal ruler. The wire of the wire-ruler assembly is inserted through the hub of a hypodermic needle, and the ruler displays the fat probe thickness straight in increments of 0.02   in. Beef cattle also accept three layers of subcutaneous fat so the person entering the needle probe in cattle must develop a technique and so the aponeurosis connective tissue is penetrated simply not the epimysial layer over the longissimus muscle. Other than using a needle probe, the process for probing cattle is like to the pig, just in cattle ane has to conform for a thicker hide thickness. In beef cattle, the hibernate thickness can be ii times the peel thickness in pigs. Real-time ultrasound data would point that there can also exist a twofold difference in hide thickness among cattle. Once the fatty thickness is recorded, it can also be used for prediction equations to estimate percent fat and muscle in the beefiness carcass.

Fig. 8.15

Fig. 8.15. An example of the needle probe used for estimating fatty thickness in beef cattle at the 12th–13th rib.

 Courtesy of P. Brackelsberg, Iowa State University, Brute Scientific discipline Department.

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Next Generation Sequencing and Its Applications

Anuj Kumar Gupta , U.D. Gupta , in Animal Biotechnology, 2014

Beefiness Cattle Option

Beef cattle are raised for meat production (as compared to dairy cattle, which are used for milk production). Traditionally, marker-assisted selection is used for the accurate selection of specific Dna variations that have been associated with a measurable difference or effect on circuitous traits. Recent advancements in sequencing and genotyping technologies take enabled a rapid development in methods for beef cattle selection from restriction fragment length polymorphism (RFLP) markers that were low-throughput and time-consuming to the new high-density single nucleotide polymorphism (SNP) assays and next generation sequencing; in comparison, marker genotypes are easily and inexpensively generated. With the rapid development of molecular technologies, new tools take become available for beefiness producers to efficiently produce loftier quality beef for today's consumer. Technologies such as side by side generation sequencing help to shorten the generation interval, to identify causal mutations, and to provide information on gene expression; this strengthens our understanding of epigenetic changes and the consequence of gut microbiomes on cattle phenotypes.

Rapid, accurate, and relatively depression cost sequencing of genomes of individual animals has the potential to revolutionize selection in beef cattle. Massively parallel sequencing information provide data about novel likewise as known polymorphisms within an individual. The discovery of mutations that actually crusade variation inside traits will go increasingly important, and their knowledge will let testing across breeds, which volition drastically reduce the number of loci that demand to exist tested to explain variations within a trait (Rolf et al., 2010).

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Systems-Thinking and Beef Cattle Production Medicine

Robert (Bob) L. Larson , in Food Safety, 2015

Abstruse

Beef cattle production is done within a organization that includes grazing on large amounts of state per cow; being fed high-calorie diets for a few months in large populations immediately prior to slaughter; long gestation and growth periods so that animals are sold for food two-3 years from the fourth dimension they were conceived; and, in most situations, more than 2 changes of ownership from birth to being sold for food. Because of the long time lags and multiple changes in ownership between intervention decisions and health and economic outcomes, a systems arroyo is necessary to accurately evaluate numerous potential direction interventions to optimize animate being health and productivity.

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Rumen

J.B. Russell , in Encyclopedia of Microbiology (Tertiary Edition), 2009

Effects of Ionophores on Ruminal Microorganisms

Beef cattle, and more recently dairy cattle, in the The states are routinely fed a course of antibiotics known as ionophores, and these compounds decrease H ii and CHiv production and increase propionate and energy retentivity. Obligate amino acrid-fermenting ruminal bacteria are also sensitive to ionophores, and this inhibition decreases NH3 production and conserves amino acids. Some lactic acrid-producing leaner are inhibited by ionophores, and this activity may modulate ruminal pH.

Ionophores translocate ions beyond cell membranes. When ion gradients (e.one thousand., potassium, sodium, and protons) are dissipated, the bacteria must expend energy to reestablish the gradients, and thus their growth is impaired. Because Gram-negative bacteria are more often than not more resistant than the Gram-positive species, it initially appeared that the outer membrane was acting as a protective barrier to exclude ionophores from the cell membrane. Notwithstanding, ionophore resistance now appears to be a more complicated phenomenon. Some Gram-positive ruminal bacteria are more sensitive to ionophores than the Gram-negative species; however, both Gram-positive and Gram-negative bacteria tin can suit. Ionophore resistance at present appears to be mediated by extracellular polysaccharides (glycocalyx) that excludes hydrophobic ionophore molecules from the jail cell membrane.

In 2006, the European Wedlock banned the use of antibiotics, including ionophores, in animal feed every bit growth promotants. Some questions then arise. How safe are ionophores? Practise ionophores increase resistance to therapeutic antibiotics? Should they be banned in the United States too? This is a very controversial discipline, only some facts can be cited: (1) ionophores take and never volition be used in human medicine due to toxicity; (two) cattle non receiving ionophores always accept big populations of ionophore-resistant bacteria; (iii) the increase in ionophore-mediated resistant leaner is quickly reversed as soon as the ionophore is removed from the diet; (4) ionophore resistance appears to exist a physiological selection that involves an increment in extracellular polysaccharide rather than a mutation- or plasmid-mediated effect; (5) the adaptation and the development of ionophore resistance in a ruminal bacterium initially sensitive to ionophore did not cause an increase in resistance to twenty therapeutic antibiotics; and (half dozen) ionophores have been very widely used for more than xx years in the United States, and there has been piffling modify in their event on the feed efficiency of cattle.

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Modelling beef cattle product to improve quality

One thousand.1000. Rickert , in Meat Processing, 2002

12.2 Elements of beef cattle production

Beef cattle product deals with the conversion of climatic and edaphic inputs into plant products, which are consumed by various classes of animals in a beefiness cattle herd to give meat for human consumption. This beef production arrangement consists of four interacting biophysical and bioeconomic subsystems, which are manipulated through the direction subsystem in response to the climate subsystem ( Fig. 12.1). The structure and significance of the various subsystems are described in more detail beneath.

Fig. 12.1. Interrelationships betwixt biophysical and bioeconomic subsystems (rectangles) with the management subsystem of the farmer. The biophysical and bioeconomic subsystems contain processes that determine their condition. The interface between two subsystems (arrows) represents a conversion of materials into a new grade. The managing director is constantly responding to the climate subsystem, which impacts to varying degrees on the soil, pasture, beast and economic subsystems.

The climate subsystem is largely exterior the management subsystem just information technology directly affects the iv subsystems influenced by a director. For example, rainfall supplies soil water for plant growth, may cause soil erosion, and influences the charge per unit of waste material decomposition in soil. Further, prevailing temperature, humidity and radiation influence plant growth, and the incidence of found and animal pests and diseases. Climatic inputs as well display seasonal and year-past-twelvemonth variations and a director must devise strategies to cope with these variations. Indeed, matching the farming system to the level and variability of climate inputs is a big claiming for a farm managing director. 12 Seasonal variations in climate requite rise to seasonal variations in quality and type of provender which may trigger fodder conservation (e.g. hay) to starting time periods of forage deficiency. wide twelvemonth-by-year variations in climate inputs, often expressed equally droughts or floods which lead to major perturbations in provender supply and market prices, demand to be handled through expert and resourceful direction. xiii However, long-term weather condition forecasts now give managers prior alert of probable climatic extremes. For example, in northern Australia seasonal forecasts point the probability of rainfall in the forthcoming three to six months exceeding the historical median value, thereby permitting managers to brand an early response to a probable distribution of rainfall. fourteen Too extremely hot or cold temperatures tin crusade deaths in plants and animals, and calculator models such as GRAZ- Program, 15 coupled to weekly weather forecasts, give early alarm of likely mortalities in susceptible classes of animals. In both cases, recent improvements in the reliability and skill of weather forecasting are helping farmers to cope with wide variations in climate.

The land subsystem supplies h2o and nutrients for plant growth. Since information technology includes many of the ecological processes that sustain the whole arrangement, both the manager and interest groups in the wider customs are dandy to keep the country subsystem in good status. Land deposition through soil erosion, desertification, salinisation, acidification and food decline is a major business organization in many of the earth's grazing lands and has led to the notion of landscape management. With this approach, managers in a region with a mutual attribute, such as a river catchment, are encouraged to adopt strategies that enhance sustainable development rather than exploitation of the land subsystem. Mural management as well recognises that grazing lands produce nutrient as well as ecosystem services, such as water and biodiversity that are needed to sustain the cities where well-nigh people alive. Preferred management strategies for a landscape may arise through dissimilar direction options being assessed by government agencies or local communities, and computer models are often useful tools in this procedure. 16

Plants within the forage subsystem supply digestible nutrients when grazed by cattle. Forage accumulates through plant growth and forage non eaten, together with faeces and urine from cattle, return to the soil subsystem through the detritus food chain. The quality of fodder on offering varies with the growing weather condition and type of plant species in the organisation. New growth is the nigh digestible and there is a steady reject in quality as constitute parts historic period, die and senesce. Since temperate grasses have a college digestibility than tropical grasses, grazing systems in temperate zones tend to brandish higher brute functioning than tropical zones, Leguminous species tend to take higher digestibility than gramineous species. 17 If a grazing organisation is based on sown pastures the director may select to abound a mixed-pasture which normally consists of a few species that are well suited to a detail situation. This contrasts with native rangelands where the system consists of many different species, often including trees. Here a manager aims to go along the pasture in good condition by maintaining acceptable plant cover to reduce soil erosion and a predominance of desirable rather than undesirable plant species. xviii In both sown pasture production systems and native rangelands, forage condition and animal performance can exist manipulated by management options such as the pick of stocking rate, type and amount of fertiliser application, periods of grazing and conservation, level of supplementary feeding, and fire in the case of rangelands. 19 , twenty

The cattle subsystem produces animals for auction through the processes of reproduction and growth within a herd consisting of unlike creature classes. The number of unlike animal classes on a farm largely depends on the quality of the pasture subsystem and on the objectives of a manager. In essence, breeding cows produce calves and after weaning these movement into different classes equally they grow and age (Table 12.1). Unremarkably immature female person cattle (heifers) are selected to supplant aged or culled cows and are mated for the outset fourth dimension when they reach maturity and a specific weight that depends on the breed and prevailing diet. Under good nutrition, heifers may be mated first at 15–18 months of age, but with the poorer nutrition in extensive rangelands, mating usually takes place at 24–30 months. Heifers that are non required for replacing cows might be sold for slaughter or for breeding purposes elsewhere. Male person cattle are commonly castrated before weaning although a small number of high-performing males may be retained to supercede anile bulls. Depending on the prevailing nutrition and markets, male person cattle may exist retained for i to iii years after weaning, to be sold for slaughter or for finishing elsewhere on another subcontract or in a feedlot. Thus, which market place to target, and how the cattle should exist fed to meet the market, are cardinal strategic decisions for a manager. Deciding when to sell specific groups of cattle is a central tactical decision for a manager.

Table 12.1. Classes of cattle commonly found in beef cattle herds in extensive grazing systems. Developed equivalent, being the ratio of the energy requirement of a class to the energy requirement of an adult animate being, is a coefficient for equating animal numbers in each class to a common base of operations. Intensive grazing systems with a higher level of nutrition will have fewer classes since cattle are sold at a younger historic period

Animal class Adult equivalent Historic period years Comments
Cows and calves 1.3 2-12 Managers aim to have breeding cows calve annually. Calves are usually weaned at about half-dozen months of age.
Yearling heifers 0.55 0.five-1.5 Heifers are females that accept not had one dogie. When mature at 1.5 to 2.v years, depending on
two-twelvemonth-sometime heifers 0.75 ane.five-2.5 breed and growing weather, some are mated to replace culled cows. Surplus heifers may exist sold for slaughter or as breeding stock.
Yearling steers 0.55 0.5-1.5 Steers, or castrated males, are sold for finishing elsewhere, or for slaughter. Historic period and weight at
2-year-old steers 0.8 1.5-2.5 sale depends on the level of nutrition they feel, the specifications of bachelor markets, and
3-year-old steers 1.0 2.5-3.five on the cost advantage of different markets. Within limits set by prevailing climatic and
4-twelvemonth-old steers one.i 3.5-four.five economic conditions, a manager tin target a specific market by manipulating feed supplies in the pasture subsytem.
Culled cows 1.0 3-12 Cows no longer suitable for breeding due to age or infertility. Usually conditioned and sold for slaughter.
Bulls ane.i iii-7 Male person animals for mating with cows. One balderdash is required for every xx to 25 cows.

The different classes of cattle in a beef herd accept different nutritional requirements because they differ in weight and historic period. The term adult equivalent (AE) relates the energy requirement of different classes to a common base of operations, the energy requirement for maintenance of an adult brute, such equally a non-lactating moo-cow. The AEs of Tabular array 12.ane can be determined from feeding tables just a first approximation for growing cattle is given by:

(12.1) A E = L W 0.75 / 105.7

where LW and LW0.75 are the liveweight and metabolic weight of animals in a specific class and 105.7 is the metabolic weight of a non-lactating bovine with a liveweight of 500 kg/caput. 21

The market subsystem refers to the different markets for beef cattle bachelor to a manager along with the prices and turn a profit margins associated with each marketplace. Specifications for markets vary with location. In an extreme example there is no specification, and all cattle are sold every bit beef with no separation of cuts at retail outlets. At the other extreme, individual animals are prepared for a specific market place and traced through the supply chain, with carcasses being graded for quality and various cuts of meat separated and sold at prices that reverberate consumer preferences and the grade. Farmers in countries that export beef, such every bit Usa, Australia, Canada and New Zealand, unremarkably have a range of market options that are specified in terms of age, gender, weight and fat thickness of a carcass. However, the classification scheme is non standardised internationally, although in that location is an international trend to reduce the commanded limits for residues of pesticide and growth promotants in export beef. Penalties for farmers in not meeting specifications for chemical residues are commonly astringent, including condemnation of all meat in the example of excess chemical residues.

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Dust Pollution from Agronomics

B. Sharratt , B. Auvermann , in Encyclopedia of Agronomics and Food Systems, 2014

Beef feedyards

Beefiness cattle are increasingly fed in confinement worldwide to capture economies of scale, increase the rate at which retail beef can be brought to market, and access markets for higher-form beef cuts as compared with animals grazing pasture or rangeland. The United States is the leading producer of cattle for slaughter, simply Australia, Canada, Argentina, Brazil, and United mexican states also have pregnant cattle-feeding industries. Developing countries in Asia, Africa, and South America are witnessing rapid growth in the beef sector as long-term disposable income rises. Although it is possible to feed cattle in confinement in temperate and loftier rainfall areas, feeding systems in those areas tend to exist under roof to reduce the amount of rainfall-driven wastewater that must exist managed, controlled, and disposed. As a outcome, open-lot cattle feeding facilities tend to be more prominent in semiarid to arid climates such as the Great Plains and Southwest regions of the United States, the Prairie Provinces in Canada, and areas of Australia west of the Swell Dividing Range in Queensland, New South Wales, and Victoria.

The master prerequisite for the development of a growing cattle sector is the availability of feed grains either from local farming or imported by rail, ship, or truck. Feed grains are the primary component in fed-cattle diets. In some regions, depending on grain markets and the calibration of food-processing or biofuel-processing industries nearby, the concentrate (or free energy and protein fraction) in fed-cattle diets may be provided past byproducts such as processed root vegetables (east.m., potatoes and beets) or spent grains (e.g., distillers grains and sweet bran). Grit emitted from cattle feedyards is derived primarily from manure excreted by the animals, therefore the blazon of feed provided to confined-beef cattle is thought to influence emission rates, airborne concentrations, and particle-size characteristics of dust.

Although the cattle are in solitude, excreted manure is deposited on the pen surface and the feed apron (which may be earthen or paved). As the manure dries and is subjected to the animals' hoof activeness, it becomes part of the pen surface either as a well-compacted manure–soil matrix or as a noncompacted layer of material dominated past manure solids. Nether dry weather condition, any mechanical disturbance of the noncompacted manure layer – whether past air current scouring, animate being hoof action, or operation of heavy machinery, will generate dust particles and entrain them in the air. This dust, known as fugitive dust or dust emitted from a diffuse or nonpoint source, consists primarily of dried manure particles merely will also include soil and waste feed particles, animal dander, exhaust from light vehicles and heavy machinery, dust from unpaved roads, and hair.

Fugitive grit emitted from a feedyard surface tends to be dominated by relatively coarse particles. The median aerodynamic diameter of fugitive dust from feedyards is in the range of 15–25   µm. Sweeten et al. (1988) reported that the ratio of PM10 to total suspended particulate (TSP) in fugitive feedyard dust, as measured by high volume samplers, is in the range of 0.19–0.40. Less is known about the relative abundance of fine particles (PM2.v) in feedyard grit, but recent measurements suggest that the PM2.five/TSP ratio is on the club of 0.05. Rainfall events reduce coarse-particle emissions to a greater extent than fine-particle emissions such that both the PM10/TSP and PM2.5/TSP ratios increase temporarily following precipitation but return to original levels within days thereafter.

Fugitive dust emissions from cattle feedyards are unremarkably expressed every bit emission fluxes (mass per unit of pen area per unit of measurement time) or emission factors (mass per beast unit of measurement per unit of measurement time). These quantities are difficult to measure directly and are normally estimated by measuring grit concentrations both upwind and downwind of the source area. The measured grit concentrations are then input to a dispersion model to infer the emission flux that would have been required to generate the deviation in measured concentrations. This indirect approach yields estimates of emission fluxes and emission factors that vary over an order of magnitude every bit shown in Tabular array ane. The high incertitude in values in Table 1 may be expected given the differences in climate, feedyard management practices, feed composition, droplets monitor performance, and dispersion-modeling algorithms across all studies.

Table ane. Published emission factors and/or fluxes of fugitive particulate matter from open up-lot beefiness cattle feedyards

Citation Study location Emission flux a (kg   ha−1 d−1) Emission gene b (thousand   per caput   d−1)
PM2.5 PM10 Total suspended particulate (TSP) PM2.five PM10 TSP
Peters and Blackwood (1977) California (USA) vi 29 114 fourteen 70 280
Parnell et al. (1999) Texas (USA) 0.6–0.8 3–4 11–15 1.4–i.8 7–9 28–36
Flocchini et al. (2001) California (The states) 1.five–6 8–31 33–122 4–fifteen twenty–75 80–300
Wanjura et al. (2004) Texas (U.s.) 1.5 eight 31 4 19 76
Lange et al. (2007) Texas (Us) 0.3–0.5 ii–iii vii–10 0.8–one.ii 4–half-dozen sixteen–24
McGinn et al. (2010) Commonwealth of australia 3–5 13–25 51–98 six–12 31–60 124–240
Bonifacio et al. (2012) Kansas (U.s.a.) 2–3 11–16 44–64 5–6 27–30 108–120
a
Emission fluxes in this table are computed from the published emission factors on the basis of a nominal creature spacing of fourteen   thouii  per head. PM2.v and PM10 are causeless to be 5% and 25% of TSP, respectively.
b
When chief data sources for these columns were provided on an animal unit basis, we have converted them to a per-head basis past bold a nominal mean live weight of 454   kg per head.

Concentrations of fugitive dust in the air downwind of beef feedyards vary diurnally and seasonally depending on emission flux, topography, atmospheric stability, particle-size distribution, and the distance downwind from the source. Because these emissions occur at ground level, increasing atmospheric stability – associated with nighttime, dumbo daytime deject cover, or atmospheric inversions – tends to favor college footing-level concentrations. Even a short-term inversion may take a dramatic influence on ground-level PM concentrations, especially when the inversion coincides with periods of increased animal action and depleted surface moisture. Under those weather condition, which are quite usually observed near sunset in semiarid and barren climates, short-term (5   min to i   h) concentrations of fugitive dust may increase 10–xv times higher than the 24-hour average concentration (Figure 4). Although the accented values of those evening summit concentrations vary up to 2 orders of magnitude from 24-hour interval to solar day, the diurnal pattern (particularly in the summer) is remarkably consistent.

Figure 4. Typical daily variation of summertime mass concentrations (5-min averages) of fugitive PM10 downwind of a cattle feedyard in the south-central United States, normalized to the 24-h average PM10 concentration.

To the extent that wind scouring is responsible for emissions from pen surfaces, wind speed, pen-surface wet content, and stocking density will all exist important factors in determining emission fluxes and predicting downwind concentrations. The mechanisms involved in these emissions will be closely analogous to those at play in current of air erosion. To date, however, current of air-driven emissions of dust from cattle feedyards remain a relatively unexplored research domain.

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Cattle priorities

Karin Due east. Schütz , ... Trevor J. DeVries , in Advances in Cattle Welfare, 2018

five.4 Conclusions

Beef and dairy cattle are managed in a range of systems that vary in the level of dietary and space intensiveness. These systems are likely to meet the animals' dietary requirements and behavioral motivations to different degrees, which are summarized in Fig. 5.vi. Cattle are particularly motivated to be able to manipulate their feed and select their diet, particularly to access roughage. Dietary preferences and resultant selection in cattle may be driven by palatability of different feedstuffs, however, information technology can also be influenced past the demand to balance food intake, avoid toxins, and maintain rumen office. Further research is needed to determine how changing physiological demands associated with growth, lactation, and pregnancy may influence dietary selection across fourth dimension. In relation to this, voluntary water consumption, which is vital for maintaining feed intake and health, is affected by water quality and its palatability, withal, there is a need for more enquiry investigating potential welfare and production consequences past providing gratis admission to clean h2o.

Figure v.vi. Summary of how different cattle management systems meet the animals' dietary requirements and ability to movement freely in high-quality infinite.

Severe constraint of move has negative effects on the welfare of cattle, whereas freedom to move is associated with good wellness and a range of normal behaviors, such as grooming. Both young and adult dairy cattle are highly motivated to exist able to move freely and to undertake other behavioral activities, such equally self-preparation, exploration, and play. Liberty of movement tin can therefore be considered a behavioral demand of cattle. This motivation seems to build upwards after a relatively curt period of severe confinement, all the same, research is needed to appraise how the motivation to move freely is influenced by housing systems that vary in their level of confinement, such as free-stall, drylot, and feedlot systems, that provide greater opportunities for motion than tie-stalls, merely not to the same extent equally pasture-based systems. Similarly, more work is also needed to sympathise the affective state of cattle in diverse housing systems.

Even though recent evidence has shown that cattle are highly motivated to admission pasture, the choices animals make depend on many different factors, such equally where the feed is provided, weather conditions, time of day, and how far the animals have to walk to access information technology. The motivation to access pasture is especially strong at dark time and may propose that pasture is a more attractive identify to lie down on, perhaps due to more infinite available and a more comfortable lying surface. Does it take to be pasture? Whereas cattle seek opportunities to appoint in grazing and foraging behavior, there is to appointment no scientific show showing the forcefulness of this motivation, and we encourage research in this area to be able to make up one's mind what it is about pasture that is attractive to cattle.

Finally, while in that location is testify that cattle seek opportunities to graze and fodder, select their diet, in particular to access roughage, and to exist able to move freely and access pasture to undertake unlike behavior activities, futurity research should also address what it means to cattle to live in a circuitous surround with plenty of opportunities for choice and control.

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