Beef Cattle

A.D. Herring , in Encyclopedia of Agriculture and Food Systems, 2014

Summary

Beef cattle are very useful in a wide range of production environments globally to supply a wide array of products. The weight and corporeality of muscle in beef cattle are important in many cultures. In some cases, it is the older animals that are utilized for beef after they have been utilized for typhoon purposes; however, it has been the supposition throughout this article that production of cattle for beef carcass markets is a primary goal. This commodity has not discussed many specific considerations involved in beef cattle production merely has attempted to point out unique aspects of beef cattle production that might exist different in other livestock species. General principles for breeding, genetics, diet, reproduction, health, and welfare are similar across livestock species, but specific knowledge and management within each species (as well equally inside combinations of brute resources, product environment, and local markets) are crucial for short-term too as long-term economic success.

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Female Reproduction

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

Introduction

Beef 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 beef 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 grooming of the uterus for successful pregnancy irrespective of whether or not an embryo is present. The embryo undergoes a flow of rapid elongation of the trophectoderm cells, and maternal recognition of pregnancy is required in order for the corpus luteum (generated by restructuring of the cells from the ovulated follicle) and progesterone concentrations in circulation to be maintained. Placental formation in beef cattle is cotyledonary in nature and quite superficial with pregnancy lasting between 279–287 days depending on brood and sexual practice of the foetus. Parturition is similar as in dairy cattle, but beef cattle do not experience the mail-partum negative free energy balance that dairy cows do and have comparative ease to become pregnant again. Specialist breeds of beef cattle are adapted to adverse conditions, e.m., tropical climates, which take led to some interesting reproductive functions. These comparative differences in female beef cattle reproduction volition be explored in greater depth in the sections below (see Table 1 for a summary).

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

Cattle (Bovine) Sheep (Ovine) Pig (Porcine) Mouse (Murine) Human being
Ovulation type Spontaneous Seasonal Continual Spontaneous Spontaneous
Ovulation number Mono-ovulatory Mono-ovulatory (mainly) Poly-ovulatory Poly-ovulatory Mono-ovulatory
Embryonic genome activation viii–xvi cell stage viii–16 jail cell phase 4–8 cell phase 2-cell stage four–8 cell stage
Completion of X-Chromosome inactivation Mail-blastocyst Possibly blastocyst Post-blastocyst Blastocyst Blastocyst
Elongation rate Rapid Rapid Extremely rapid Northward/A N/A
Pregnancy recognition indicate Bovine Ovine Estrogens Prolactin Human 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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Nutrition, feeding and management of beefiness cattle in intensive and extensive production systems

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

Conclusion

Beef cattle are unique, compared to poultry and swine in that they can catechumen low-quality forages into high-quality protein for humans. Recently, there has been growing force per unit area to globally restrict beefiness production, due to its perceived negative bear upon on the environment. Beef cattle play a significant role in the production of nutrient for humans, from forages and vast tracks of both tame and native pasturelands. In native grasslands, beef cattle largely replace the role of the bison that previously occupied this ecosystem. Care must be taken to ensure that the nutritional needs of beef cattle are aligned with the productivity of the pasture, and then as to avoid detrimental impacts on both the animal and the ecosystem. Global ambition for beef is projected to increase and in light of the emerging pressures of climate change and the scarcity of new tracts of pasture and abundant land, sustainable intensification will exist the merely ways of satisfying need. Intensified systems will need to increase the use of by-product feeds and food wastes in beef cattle production. Nutrient management plans volition 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 accent on both the plant and the animal will need to gain societal credence if more than beef is to be produced on less country. 93 , 95

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Methods to measure body composition of domestic animals

Steven M. Lonergan , ... Dennis North. Marple , in The Science of Animal Growth and Meat Engineering (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 peel approximately 5  in. from the midline betwixt the 12th and 13th ribs. A modified needle probe is unremarkably used in beef cattle rather than a pocket-sized ruler that is used in pigs (Fig. viii.15). The needle probe is more constructive for penetrating the thick skin of beef cattle and consists of a thick stainless steel wire attached to a metal ruler. The wire of the wire-ruler associates is inserted through the hub of a hypodermic needle, and the ruler displays the fat probe thickness directly in increments of 0.02   in. Beef cattle also take 3 layers of subcutaneous fat so the person entering the needle probe in cattle must develop a technique so the aponeurosis connective tissue is penetrated simply non the epimysial layer over the longissimus muscle. Other than using a needle probe, the process for probing cattle is similar to the pig, but in cattle one has to conform for a thicker hibernate thickness. In beefiness cattle, the hide thickness can be two times the skin thickness in pigs. Real-fourth dimension ultrasound data would indicate that there tin also exist a twofold deviation in hibernate thickness amidst cattle. Once the fat thickness is recorded, it can likewise be used for prediction equations to estimate percentage fat and musculus in the beef carcass.

Fig. 8.15

Fig. eight.15. An case of the needle probe used for estimating fatty thickness in beefiness cattle at the 12th–13th rib.

 Courtesy of P. Brackelsberg, Iowa State University, Animal Science Department.

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Next Generation Sequencing and Its Applications

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

Beef Cattle Selection

Beef cattle are raised for meat production (every bit compared to dairy cattle, which are used for milk production). Traditionally, marker-assisted pick is used for the accurate selection of specific DNA variations that take been associated with a measurable difference or effect on complex traits. Contempo advancements in sequencing and genotyping technologies accept enabled a rapid evolution in methods for beefiness cattle pick from restriction fragment length polymorphism (RFLP) markers that were low-throughput and fourth dimension-consuming to the new high-density unmarried nucleotide polymorphism (SNP) assays and next generation sequencing; in comparing, marker genotypes are easily and inexpensively generated. With the rapid development of molecular technologies, new tools have go available for beefiness producers to efficiently produce high quality beefiness for today'south consumer. Technologies such as next generation sequencing help to shorten the generation interval, to identify causal mutations, and to provide information on cistron expression; this strengthens our agreement of epigenetic changes and the effect of gut microbiomes on cattle phenotypes.

Rapid, accurate, and relatively low cost sequencing of genomes of individual animals has the potential to revolutionize selection in beef cattle. Massively parallel sequencing information provide information about novel as well as known polymorphisms within an individual. The discovery of mutations that actually cause variation within traits will become increasingly of import, and their knowledge volition allow testing across breeds, which volition drastically reduce the number of loci that demand to be tested to explicate variations inside a trait (Rolf et al., 2010).

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Systems-Thinking and Beef Cattle Product Medicine

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

Abstract

Beef cattle product is done inside a arrangement that includes grazing on large amounts of country per moo-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 2-3 years from the fourth dimension they were conceived; and, in near situations, more than than two 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 approach is necessary to accurately evaluate numerous potential management interventions to optimize animal health and productivity.

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Rumen

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

Effects of Ionophores on Ruminal Microorganisms

Beefiness cattle, and more recently dairy cattle, in the United States are routinely fed a class of antibiotics known equally ionophores, and these compounds decrease H 2 and CHfour production and increase propionate and free energy retention. Obligate amino acid-fermenting ruminal leaner are too sensitive to ionophores, and this inhibition decreases NH3 product and conserves amino acids. Some lactic acid-producing bacteria are inhibited by ionophores, and this activity may attune ruminal pH.

Ionophores translocate ions across prison cell membranes. When ion gradients (e.m., potassium, sodium, and protons) are dissipated, the bacteria must expend free energy to reestablish the gradients, and thus their growth is impaired. Considering Gram-negative leaner are generally 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. However, ionophore resistance at present appears to be a more complicated phenomenon. Some Gram-positive ruminal leaner are more than sensitive to ionophores than the Gram-negative species; however, both Gram-positive and Gram-negative leaner can arrange. Ionophore resistance at present appears to exist mediated by extracellular polysaccharides (glycocalyx) that excludes hydrophobic ionophore molecules from the cell membrane.

In 2006, the European Spousal relationship banned the use of antibiotics, including ionophores, in animal feed as growth promotants. Some questions then arise. How safe are ionophores? Do ionophores increment resistance to therapeutic antibiotics? Should they exist banned in the United States too? This is a very controversial subject, but some facts can be cited: (1) ionophores accept and never will be used in human medicine due to toxicity; (2) cattle non receiving ionophores e'er have big populations of ionophore-resistant bacteria; (3) the increment in ionophore-mediated resistant bacteria is apace reversed every bit soon as the ionophore is removed from the nutrition; (four) ionophore resistance appears to be a physiological pick that involves an increase in extracellular polysaccharide rather than a mutation- or plasmid-mediated event; (5) the adaptation and the development of ionophore resistance in a ruminal bacterium initially sensitive to ionophore did not crusade an increase in resistance to xx therapeutic antibiotics; and (vi) ionophores take been very widely used for more than xx years in the United States, and there has been fiddling change in their effect on the feed efficiency of cattle.

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Modelling beef cattle production to improve quality

K.K. Rickert , in Meat Processing, 2002

12.2 Elements of beef cattle production

Beef cattle production deals with the conversion of climatic and edaphic inputs into plant products, which are consumed past various classes of animals in a beef cattle herd to requite meat for human consumption. This beef production system consists of iv interacting biophysical and bioeconomic subsystems, which are manipulated through the management subsystem in response to the climate subsystem ( Fig. 12.1). The structure and significance of the diverse subsystems are described in more particular below.

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 make up one's mind their status. The interface between two subsystems (arrows) represents a conversion of materials into a new form. The manager is constantly responding to the climate subsystem, which impacts to varying degrees on the soil, pasture, animate being and economic subsystems.

The climate subsystem is largely outside the direction subsystem but it direct affects the four subsystems influenced by a director. For case, rainfall supplies soil water for institute growth, may cause soil erosion, and influences the rate of waste decomposition in soil. Further, prevailing temperature, humidity and radiation influence plant growth, and the incidence of plant and animal pests and diseases. Climatic inputs also brandish seasonal and year-by-year variations and a manager must devise strategies to cope with these variations. Indeed, matching the farming system to the level and variability of climate inputs is a large claiming for a farm director. 12 Seasonal variations in climate give rise to seasonal variations in quality and type of fodder which may trigger fodder conservation (e.g. hay) to first periods of forage deficiency. wide year-by-year variations in climate inputs, often expressed as droughts or floods which atomic number 82 to major perturbations in forage supply and market place prices, demand to be handled through proficient and resourceful management. 13 However, long-term atmospheric condition forecasts at present give managers prior alert of likely climatic extremes. For case, in northern Commonwealth of australia seasonal forecasts indicate the probability of rainfall in the forthcoming three to six months exceeding the historical median value, thereby permitting managers to make an early response to a probable distribution of rainfall. xiv Also extremely hot or common cold temperatures tin cause deaths in plants and animals, and computer models such equally GRAZ- Plan, fifteen 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 country subsystem supplies h2o and nutrients for plant growth. Since it includes many of the ecological processes that sustain the whole arrangement, both the manager and involvement groups in the wider community are keen to continue the land subsystem in good condition. State degradation through soil erosion, desertification, salinisation, acidification and nutrient decline is a major concern in many of the earth'south grazing lands and has led to the notion of landscape management. With this approach, managers in a region with a common attribute, such as a river catchment, are encouraged to adopt strategies that enhance sustainable development rather than exploitation of the land subsystem. Mural management likewise recognises that grazing lands produce nutrient as well as ecosystem services, such as h2o and biodiversity that are needed to sustain the cities where almost people alive. Preferred direction strategies for a landscape may ascend through different management options being assessed by government agencies or local communities, and computer models are often useful tools in this process. xvi

Plants inside the forage subsystem supply digestible nutrients when grazed past cattle. Forage accumulates through plant growth and fodder not eaten, together with faeces and urine from cattle, return to the soil subsystem through the detritus nutrient chain. The quality of fodder on offering varies with the growing weather and blazon of constitute species in the system. New growth is the almost digestible and there is a steady pass up in quality as plant parts age, die and senesce. Since temperate grasses have a college digestibility than tropical grasses, grazing systems in temperate zones tend to display higher fauna performance 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 grow a mixed-pasture which usually consists of a few species that are well suited to a particular situation. This contrasts with native rangelands where the system consists of many different species, frequently including trees. Here a director aims to keep the pasture in skilful condition past maintaining adequate establish embrace to reduce soil erosion and a predominance of desirable rather than undesirable institute species. 18 In both sown pasture product systems and native rangelands, forage condition and beast performance tin can be manipulated past direction options such as the choice of stocking rate, blazon and amount of fertiliser application, periods of grazing and conservation, level of supplementary feeding, and burn down in the case of rangelands. nineteen , 20

The cattle subsystem produces animals for auction through the processes of reproduction and growth inside a herd consisting of dissimilar animal 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 managing director. In essence, convenance cows produce calves and after weaning these movement into different classes as they grow and historic period (Table 12.one). Commonly young female cattle (heifers) are selected to supercede aged or culled cows and are mated for the first time when they reach maturity and a specific weight that depends on the brood and prevailing nutrition. Under good nutrition, heifers may be mated first at fifteen–xviii months of age, but with the poorer nutrition in extensive rangelands, mating usually takes identify at 24–30 months. Heifers that are not required for replacing cows might be sold for slaughter or for breeding purposes elsewhere. Male person cattle are commonly castrated earlier weaning although a small number of high-performing males may be retained to replace anile bulls. Depending on the prevailing nutrition and markets, male person cattle may exist retained for one to iii years after weaning, to be sold for slaughter or for finishing elsewhere on another farm or in a feedlot. Thus, which marketplace to target, and how the cattle should be fed to meet the market, are fundamental strategic decisions for a manager. Deciding when to sell specific groups of cattle is a primal tactical conclusion for a managing director.

Table 12.i. Classes of cattle commonly plant in beefiness cattle herds in extensive grazing systems. Adult equivalent, beingness the ratio of the energy requirement of a class to the energy requirement of an adult brute, is a coefficient for equating beast numbers in each class to a common base. Intensive grazing systems with a higher level of nutrition will have fewer classes since cattle are sold at a younger age

Creature class Adult equivalent Age years Comments
Cows and calves 1.iii 2-12 Managers aim to take breeding cows calve annually. Calves are usually weaned at about 6 months of age.
Yearling heifers 0.55 0.5-1.5 Heifers are females that have not had one calf. When mature at 1.5 to 2.5 years, depending on
2-twelvemonth-sometime heifers 0.75 1.5-two.v breed and growing atmospheric condition, some are mated to supervene upon culled cows. Surplus heifers may be 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. Age and weight at
2-yr-old steers 0.8 1.five-2.five sale depends on the level of nutrition they experience, the specifications of available markets, and
3-twelvemonth-old steers 1.0 two.5-3.5 on the cost advantage of unlike markets. Inside limits set by prevailing climatic and
4-year-old steers i.1 3.5-4.5 economic weather, a manager tin can target a specific marketplace by manipulating feed supplies in the pasture subsytem.
Culled cows ane.0 3-12 Cows no longer suitable for breeding due to age or infertility. Commonly conditioned and sold for slaughter.
Bulls 1.1 iii-7 Male person animals for mating with cows. I bull is required for every 20 to 25 cows.

The different classes of cattle in a beefiness herd accept different nutritional requirements because they differ in weight and age. The term developed equivalent (AE) relates the energy requirement of unlike classes to a common base of operations, the energy requirement for maintenance of an adult animal, such as a non-lactating cow. The AEs of Table 12.1 can be determined from feeding tables just a first approximation for growing cattle is given by:

(12.1) A East = L Westward 0.75 / 105.7

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

The market place subsystem refers to the different markets for beef cattle available to a manager along with the prices and turn a profit margins associated with each market. Specifications for markets vary with location. In an extreme case there is no specification, and all cattle are sold as beefiness 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 reflect consumer preferences and the grade. Farmers in countries that export beefiness, such as U.s., Australia, Canada and New Zealand, commonly have a range of market options that are specified in terms of age, gender, weight and fatty thickness of a carcass. However, the classification scheme is not standardised internationally, although there is an international trend to reduce the allowable limits for residues of pesticide and growth promotants in export beef. Penalties for farmers in not meeting specifications for chemical residues are usually severe, including condemnation of all meat in the example of backlog chemical residues.

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Grit Pollution from Agronomics

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

Beef feedyards

Beef cattle are increasingly fed in solitude worldwide to capture economies of scale, increase the rate at which retail beef can exist brought to marketplace, and access markets for college-grade beef cuts as compared with animals grazing pasture or rangeland. The Us is the leading producer of cattle for slaughter, but Australia, Canada, Argentina, Brazil, and United mexican states as well have significant 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 information technology is possible to feed cattle in confinement in temperate and high rainfall areas, feeding systems in those areas tend to be under roof to reduce the amount of rainfall-driven wastewater that must be managed, controlled, and tending. As a issue, open-lot cattle feeding facilities tend to be more prominent in semiarid to arid climates such every bit the Dandy Plains and Southwest regions of the U.s.a., the Prairie Provinces in Canada, and areas of Commonwealth of australia west of the Bully Dividing Range in Queensland, New Southward Wales, and Victoria.

The chief prerequisite for the development of a growing cattle sector is the availability of feed grains either from local farming or imported by rail, send, or truck. Feed grains are the primary component in fed-cattle diets. In some regions, depending on grain markets and the scale of food-processing or biofuel-processing industries nearby, the concentrate (or energy and poly peptide fraction) in fed-cattle diets may be provided by byproducts such as processed root vegetables (east.yard., potatoes and beets) or spent grains (e.thousand., distillers grains and sweet bran). Dust emitted from cattle feedyards is derived primarily from manure excreted by the animals, therefore the type 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 confinement, excreted manure is deposited on the pen surface and the feed frock (which may be earthen or paved). As the manure dries and is subjected to the animals' hoof activity, it becomes office of the pen surface either as a well-compacted manure–soil matrix or as a noncompacted layer of material dominated by manure solids. Under dry conditions, any mechanical disturbance of the noncompacted manure layer – whether by wind scouring, animal hoof activity, or operation of heavy machinery, will generate dust particles and entrain them in the air. This dust, known equally fugitive dust or dust emitted from a diffuse or nonpoint source, consists primarily of stale manure particles but will also include soil and waste feed particles, animal dander, exhaust from light vehicles and heavy machinery, grit from unpaved roads, and pilus.

Fugitive dust emitted from a feedyard surface tends to be dominated by relatively fibroid 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 past high book samplers, is in the range of 0.nineteen–0.xl. Less is known about the relative abundance of fine particles (PM2.5) in feedyard dust, but recent measurements suggest that the PM2.v/TSP ratio is on the order 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 increment temporarily following precipitation merely return to original levels within days thereafter.

Avoiding grit emissions from cattle feedyards are ordinarily expressed as emission fluxes (mass per unit of pen area per unit fourth dimension) or emission factors (mass per beast unit per unit time). These quantities are difficult to measure out directly and are commonly estimated by measuring dust concentrations both upwind and downwind of the source expanse. The measured grit concentrations are then input to a dispersion model to infer the emission flux that would have been required to generate the difference in measured concentrations. This indirect approach yields estimates of emission fluxes and emission factors that vary over an order of magnitude as shown in Table 1. The loftier uncertainty in values in Table i may exist expected given the differences in climate, feedyard management practices, feed composition, droplets monitor operation, and dispersion-modeling algorithms across all studies.

Table 1. Published emission factors and/or fluxes of fugitive particulate affair from open up-lot beef cattle feedyards

Citation Report location Emission flux a (kg   ha−1 d−ane) Emission factor b (g   per head   d−1)
PM2.5 PM10 Total suspended particulate (TSP) PM2.five PM10 TSP
Peters and Blackwood (1977) California (U.s.) 6 29 114 xiv seventy 280
Parnell et al. (1999) Texas (United states) 0.half-dozen–0.8 iii–4 xi–15 1.four–ane.8 7–nine 28–36
Flocchini et al. (2001) California (USA) ane.v–vi viii–31 33–122 iv–fifteen xx–75 lxxx–300
Wanjura et al. (2004) Texas (USA) 1.5 8 31 four xix 76
Lange et al. (2007) Texas (USA) 0.3–0.5 two–iii 7–10 0.8–1.ii four–6 xvi–24
McGinn et al. (2010) Australia 3–5 thirteen–25 51–98 6–12 31–60 124–240
Bonifacio et al. (2012) Kansas (U.s.) 2–3 eleven–16 44–64 v–half-dozen 27–30 108–120
a
Emission fluxes in this tabular array are computed from the published emission factors on the basis of a nominal animal spacing of 14   m2  per head. PM2.5 and PM10 are assumed to be five% and 25% of TSP, respectively.
b
When primary data sources for these columns were provided on an animal unit of measurement basis, we have converted them to a per-head basis by bold a nominal hateful live weight of 454   kg per head.

Concentrations of fugitive grit 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, dense daytime cloud encompass, or atmospheric inversions – tends to favor college ground-level concentrations. Even a short-term inversion may accept a dramatic influence on basis-level PM concentrations, peculiarly when the inversion coincides with periods of increased animal activity and depleted surface wet. Under those conditions, which are quite commonly observed nigh dusk in semiarid and arid climates, short-term (5   min to 1   h) concentrations of fugitive dust may increase 10–15 times college than the 24-60 minutes boilerplate concentration (Effigy iv). Although the absolute values of those evening peak concentrations vary upwardly to 2 orders of magnitude from day to day, the diurnal pattern (specially in the summertime) is remarkably consequent.

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

To the extent that wind scouring is responsible for emissions from pen surfaces, wind speed, pen-surface moisture content, and stocking density will all be 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 air current erosion. To date, however, wind-driven emissions of dust from cattle feedyards remain a relatively unexplored research domain.

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Cattle priorities

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

5.4 Conclusions

Beefiness 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 see the animals' dietary requirements and behavioral motivations to different degrees, which are summarized in Fig. 5.6. Cattle are particularly motivated to be able to manipulate their feed and select their diet, especially to admission roughage. Dietary preferences and resultant selection in cattle may be driven by palatability of unlike feedstuffs, however, it tin also be influenced by the demand to residue food intake, avoid toxins, and maintain rumen office. Further research is needed to make up one's mind how changing physiological demands associated with growth, lactation, and pregnancy may influence dietary selection beyond time. In relation to this, voluntary water consumption, which is vital for maintaining feed intake and health, is affected by water quality and its palatability, however, in that location is a demand for more research investigating potential welfare and production consequences by providing gratuitous admission to clean water.

Figure v.6. Summary of how different cattle management systems come across the animals' dietary requirements and ability to move freely in high-quality space.

Severe constraint of movement has negative effects on the welfare of cattle, whereas freedom to move is associated with good health and a range of normal behaviors, such as preparation. Both young and developed dairy cattle are highly motivated to be able to move freely and to undertake other behavioral activities, such as cocky-preparation, exploration, and play. Freedom of motion can therefore exist considered a behavioral need of cattle. This motivation seems to build up after a relatively brusque period of severe confinement, nevertheless, inquiry is needed to appraise how the motivation to move freely is influenced by housing systems that vary in their level of solitude, such every bit free-stall, drylot, and feedlot systems, that provide greater opportunities for movement than tie-stalls, but not to the aforementioned extent as pasture-based systems. Similarly, more piece of work is besides needed to understand the affective land of cattle in diverse housing systems.

Even though recent testify has shown that cattle are highly motivated to access pasture, the choices animals make depend on many unlike factors, such every bit where the feed is provided, weather conditions, fourth dimension of solar day, and how far the animals take to walk to access it. The motivation to access pasture is particularly strong at dark time and may suggest that pasture is a more than attractive place to lie down on, mayhap due to more space available and a more comfortable lying surface. Does it accept to exist pasture? Whereas cattle seek opportunities to engage in grazing and foraging beliefs, there is to date no scientific evidence showing the force of this motivation, and we encourage research in this area to be able to make up one's mind what information technology is most pasture that is attractive to cattle.

Finally, while there is bear witness that cattle seek opportunities to graze and forage, select their diet, in particular to access roughage, and to exist able to motility freely and access pasture to undertake different behavior activities, future research should likewise accost what it means to cattle to live in a complex environment with plenty of opportunities for choice and control.

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