Beef Cattle

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

Summary

Beefiness 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 beefiness 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 draft purposes; however, it has been the assumption throughout this commodity that product of cattle for beefiness carcass markets is a primary goal. This article has not discussed many specific considerations involved in beef cattle production just has attempted to point out unique aspects of beefiness cattle product that might be different in other livestock species. General principles for convenance, genetics, nutrition, reproduction, health, and welfare are similar beyond livestock species, but specific knowledge and direction within each species (every bit well equally within combinations of brute resources, production environs, and local markets) are crucial for short-term every bit well as long-term economic success.

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Female person 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 beef heifer begins to cycle on a regular ground and commonly coincides with the heifer reaching 50% of its developed weight at approximately 12–15 months of age. The estrous bike is regulated in a similar manner to other mono-ovulatory species with the preparation of the uterus for successful pregnancy irrespective of whether or non an embryo is nowadays. The embryo undergoes a period of rapid elongation of the trophectoderm cells, and maternal recognition of pregnancy is required in society for the corpus luteum (generated by restructuring of the cells from the ovulated follicle) and progesterone concentrations in circulation to exist maintained. Placental formation in beef cattle is cotyledonary in nature and quite superficial with pregnancy lasting between 279–287 days depending on breed and sex of the foetus. Parturition is similar as in dairy cattle, but beefiness cattle practise not experience the post-partum negative energy residuum that dairy cows do and have comparative ease to become pregnant again. Specialist breeds of beef cattle are adapted to agin atmospheric condition, due east.thousand., tropical climates, which have led to some interesting reproductive functions. These comparative differences in female beef cattle reproduction will be explored in greater depth in the sections beneath (come across Tabular array 1 for a summary).

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

Cattle (Bovine) Sheep (Ovine) Pig (Porcine) Mouse (Murine) Human
Ovulation blazon Spontaneous Seasonal Continual Spontaneous Spontaneous
Ovulation number Mono-ovulatory Mono-ovulatory (mainly) Poly-ovulatory Poly-ovulatory Mono-ovulatory
Embryonic genome activation 8–16 cell stage 8–16 cell phase 4–8 cell stage 2-jail cell phase iv–8 prison cell stage
Completion of X-Chromosome inactivation Postal service-blastocyst Possibly blastocyst Post-blastocyst Blastocyst Blastocyst
Elongation rate Rapid Rapid Extremely rapid N/A N/A
Pregnancy recognition indicate Bovine Ovine Estrogens Prolactin Homo 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 beef cattle in intensive and extensive production systems

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

Conclusion

Beef cattle are unique, compared to poultry and swine in that they can catechumen low-quality forages into loftier-quality poly peptide for humans. Recently, in that location has been growing pressure to globally restrict beefiness production, due to its perceived negative impact on the surroundings. Beef cattle play a pregnant function in the production of nutrient for humans, from forages and vast tracks of both tame and native pasturelands. In native grasslands, beef cattle largely supercede the office of the bison that previously occupied this ecosystem. Care must exist taken to ensure that the nutritional needs of beef cattle are aligned with the productivity of the pasture, so as to avert detrimental impacts on both the animal and the ecosystem. Global appetite for beef is projected to increase and in light of the emerging pressures of climatic change and the scarcity of new tracts of pasture and abundant country, sustainable intensification will be the only means of satisfying demand. Intensified systems volition need to increase the use of past-product feeds and food wastes in beef cattle product. Nutrient management plans volition be needed to ensure that nutrient flows are aligned with the principals of a round bioeconomy. Finally, avant-garde technologies that improve the efficiency of feed utilization with an accent on both the plant and the animal will demand to gain societal credence if more than beefiness is to be produced on less land. 93 , 95

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Methods to measure body limerick of domestic animals

Steven M. Lonergan , ... Dennis N. Marple , in The Science of Fauna Growth and Meat Applied science (2d Edition), 2019

Backfat probe for cattle

Beef cattle must exist restrained before the fatty-probing process is started. In cattle, the fat thickness probe is placed through the skin approximately 5  in. from the midline between the twelfth and 13th ribs. A modified needle probe is ordinarily used in beefiness cattle rather than a small ruler that is used in pigs (Fig. 8.15). The needle probe is more effective for penetrating the thick peel 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 directly in increments of 0.02   in. Beef cattle also have 3 layers of subcutaneous fatty so the person entering the needle probe in cattle must develop a technique so the aponeurosis connective tissue is penetrated just non the epimysial layer over the longissimus muscle. Other than using a needle probe, the procedure for probing cattle is similar to the sus scrofa, simply in cattle one has to arrange for a thicker hide thickness. In beef cattle, the hide thickness can be two times the skin thickness in pigs. Real-time ultrasound data would signal that at that place can too be a twofold divergence in hide thickness among cattle. Once the fat thickness is recorded, it can also exist used for prediction equations to guess percentage fat and musculus in the beef carcass.

Fig. 8.15

Fig. 8.xv. An instance of the needle probe used for estimating fat thickness in beef cattle at the 12th–13th rib.

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

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Next Generation Sequencing and Its Applications

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

Beef Cattle Option

Beef cattle are raised for meat production (as compared to dairy cattle, which are used for milk product). Traditionally, marker-assisted option is used for the accurate choice of specific Deoxyribonucleic acid variations that accept been associated with a measurable deviation or effect on complex traits. Recent advancements in sequencing and genotyping technologies take enabled a rapid development in methods for beef cattle choice from brake fragment length polymorphism (RFLP) markers that were low-throughput and time-consuming to the new high-density unmarried nucleotide polymorphism (SNP) assays and adjacent generation sequencing; in comparison, marker genotypes are easily and inexpensively generated. With the rapid evolution of molecular technologies, new tools take get available for beef producers to efficiently produce high quality beefiness for today'due south consumer. Technologies such equally adjacent generation sequencing aid to shorten the generation interval, to place causal mutations, and to provide information on gene expression; this strengthens our understanding 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 pick in beef cattle. Massively parallel sequencing data provide information near novel as well as known polymorphisms within an individual. The discovery of mutations that actually cause variation within traits will become increasingly important, and their knowledge volition allow testing across breeds, which will drastically reduce the number of loci that need to be tested to explain variations inside a trait (Rolf et al., 2010).

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Systems-Thinking and Beefiness Cattle Product Medicine

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

Abstract

Beef cattle product is done within a organisation that includes grazing on large amounts of land per cow; being fed high-calorie diets for a few months in large populations immediately prior to slaughter; long gestation and growth periods and then that animals are sold for nutrient two-3 years from the time they were conceived; and, in most situations, more than than 2 changes of buying from nascency to being sold for nutrient. Because of the long time lags and multiple changes in ownership betwixt intervention decisions and wellness and economic outcomes, a systems approach is necessary to accurately evaluate numerous potential management interventions to optimize animate being 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 grade of antibiotics known as ionophores, and these compounds decrease H 2 and CH4 production and increase propionate and energy retention. Obligate amino acrid-fermenting ruminal leaner are likewise sensitive to ionophores, and this inhibition decreases NH3 production and conserves amino acids. Some lactic acid-producing bacteria are inhibited past ionophores, and this activity may modulate ruminal pH.

Ionophores translocate ions across jail cell membranes. When ion gradients (eastward.m., 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 generally more than 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. Still, ionophore resistance now appears to exist a more complicated miracle. Some Gram-positive ruminal leaner are more sensitive to ionophores than the Gram-negative species; however, both Gram-positive and Gram-negative bacteria can conform. Ionophore resistance at present appears to be mediated by extracellular polysaccharides (glycocalyx) that excludes hydrophobic ionophore molecules from the prison cell membrane.

In 2006, the European Union banned the apply of antibiotics, including ionophores, in animal feed equally growth promotants. Some questions then arise. How condom are ionophores? Do ionophores increase resistance to therapeutic antibiotics? Should they be banned in the United States as well? This is a very controversial field of study, simply some facts can be cited: (1) ionophores take and never will be used in human medicine due to toxicity; (2) cattle not receiving ionophores always accept big populations of ionophore-resistant bacteria; (iii) the increase in ionophore-mediated resistant bacteria is quickly reversed as soon as the ionophore is removed from the diet; (iv) ionophore resistance appears to be a physiological selection that involves an increase in extracellular polysaccharide rather than a mutation- or plasmid-mediated issue; (5) the adaptation and the evolution of ionophore resistance in a ruminal bacterium initially sensitive to ionophore did not cause an increase in resistance to twenty therapeutic antibiotics; and (6) ionophores take been very widely used for more than 20 years in the United States, and there has been niggling change in their issue on the feed efficiency of cattle.

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Modelling beef cattle production to improve quality

K.Thou. Rickert , in Meat Processing, 2002

12.ii Elements of beefiness cattle product

Beefiness cattle production deals with the conversion of climatic and edaphic inputs into establish products, which are consumed by diverse classes of animals in a beef cattle herd to give meat for human consumption. This beef production system consists of 4 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.ane. 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 betwixt 2 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, animal and economic subsystems.

The climate subsystem is largely outside the management subsystem merely it directly affects the four subsystems influenced by a manager. For case, rainfall supplies soil water for plant growth, may cause soil erosion, and influences the charge per unit of waste decomposition in soil. Further, prevailing temperature, humidity and radiations influence plant growth, and the incidence of constitute and creature pests and diseases. Climatic inputs also display seasonal and year-by-year variations and a managing director must devise strategies to cope with these variations. Indeed, matching the farming system to the level and variability of climate inputs is a large challenge for a farm director. 12 Seasonal variations in climate give rise to seasonal variations in quality and type of forage which may trigger forage conservation (e.g. hay) to offset periods of forage deficiency. wide yr-by-year variations in climate inputs, often expressed as droughts or floods which lead to major perturbations in forage supply and market prices, demand to be handled through expert and resourceful management. xiii However, long-term weather forecasts now give managers prior warning of likely climatic extremes. For instance, in northern Australia seasonal forecasts indicate the probability of rainfall in the forthcoming three to half-dozen months exceeding the historical median value, thereby permitting managers to make an early response to a likely distribution of rainfall. xiv Also extremely hot or cold temperatures tin can cause deaths in plants and animals, and computer models such as GRAZ- Programme, 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 conditions forecasting are helping farmers to cope with wide variations in climate.

The land subsystem supplies water and nutrients for institute growth. Since it includes many of the ecological processes that sustain the whole organization, both the manager and interest groups in the wider community are keen to continue the land subsystem in good condition. Land degradation through soil erosion, desertification, salinisation, acidification and food decline is a major concern in many of the earth'due south grazing lands and has led to the notion of landscape direction. With this approach, managers in a region with a common attribute, such every bit a river catchment, are encouraged to adopt strategies that raise sustainable development rather than exploitation of the land subsystem. Landscape management likewise recognises that grazing lands produce nutrient as well equally ecosystem services, such equally water and biodiversity that are needed to sustain the cities where most people alive. Preferred management strategies for a mural may arise through different management options beingness assessed by government agencies or local communities, and computer models are often useful tools in this procedure. xvi

Plants within the forage subsystem supply digestible nutrients when grazed by cattle. Forage accumulates through plant growth and forage not eaten, together with faeces and urine from cattle, render to the soil subsystem through the detritus food chain. The quality of forage on offer varies with the growing conditions and blazon of plant species in the organisation. New growth is the most digestible and there is a steady decline in quality as plant parts age, dice and senesce. Since temperate grasses have a higher digestibility than tropical grasses, grazing systems in temperate zones tend to brandish higher creature performance than tropical zones, Leguminous species tend to have higher digestibility than gramineous species. 17 If a grazing organization is based on sown pastures the manager may select to grow a mixed-pasture which usually 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 copse. Here a managing director aims to keep the pasture in good condition by maintaining adequate constitute cover to reduce soil erosion and a predominance of desirable rather than undesirable plant species. 18 In both sown pasture product systems and native rangelands, fodder condition and animal performance can be manipulated past management options such as the option of stocking rate, type and amount of fertiliser application, periods of grazing and conservation, level of supplementary feeding, and fire in the instance of rangelands. 19 , twenty

The cattle subsystem produces animals for sale through the processes of reproduction and growth within a herd consisting of different creature classes. The number of different animal classes on a farm largely depends on the quality of the pasture subsystem and on the objectives of a manager. In essence, convenance cows produce calves and after weaning these move into different classes equally they abound and historic period (Table 12.1). Usually young female cattle (heifers) are selected to supersede aged or culled cows and are mated for the first fourth dimension when they reach maturity and a specific weight that depends on the breed and prevailing nutrition. Under skillful diet, heifers may be mated outset at xv–xviii months of age, simply with the poorer nutrition in all-encompassing rangelands, mating commonly takes place 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 before weaning although a small number of loftier-performing males may be retained to replace anile bulls. Depending on the prevailing nutrition and markets, male person cattle may be retained for 1 to three years after weaning, to exist sold for slaughter or for finishing elsewhere on another farm or in a feedlot. Thus, which market to target, and how the cattle should be fed to meet the market, are primal strategic decisions for a manager. Deciding when to sell specific groups of cattle is a key tactical decision for a manager.

Table 12.1. Classes of cattle commonly found in beef cattle herds in extensive grazing systems. Adult equivalent, being the ratio of the energy requirement of a grade to the energy requirement of an adult animal, is a coefficient for equating beast numbers in each class to a mutual base. 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 i.3 ii-12 Managers aim to accept breeding cows calve annually. Calves are usually weaned at nearly half-dozen months of age.
Yearling heifers 0.55 0.v-ane.5 Heifers are females that have not had one calf. When mature at one.5 to ii.5 years, depending on
ii-year-old heifers 0.75 ane.five-2.5 breed and growing weather condition, some are mated to replace 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. Historic period and weight at
2-yr-old steers 0.8 1.five-2.five sale depends on the level of diet they experience, the specifications of available markets, and
3-twelvemonth-old steers one.0 2.5-3.5 on the price reward of dissimilar markets. Within limits set by prevailing climatic and
four-yr-old steers 1.i 3.v-iv.5 economic weather, a director can target a specific market place by manipulating feed supplies in the pasture subsytem.
Culled cows one.0 3-12 Cows no longer suitable for breeding due to age or infertility. Usually conditioned and sold for slaughter.
Bulls one.1 3-7 Male animals for mating with cows. One bull is required for every 20 to 25 cows.

The unlike classes of cattle in a beef herd have 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, the free energy requirement for maintenance of an adult animal, such every bit a non-lactating moo-cow. The AEs of Table 12.1 tin be determined from feeding tables but a offset approximation for growing cattle is given past:

(12.1) A East = 50 W 0.75 / 105.7

where LW and LW0.75 are the liveweight and metabolic weight of animals in a specific class and 105.vii is the metabolic weight of a non-lactating bovine with a liveweight of 500 kg/head. 21

The marketplace subsystem refers to the different markets for beef cattle available to a managing director forth with the prices and profit margins associated with each market place. 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 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 course. Farmers in countries that consign beefiness, such as USA, Commonwealth of australia, Canada and New Zealand, commonly 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 not standardised internationally, although there 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 chemic residues are commonly severe, including condemnation of all meat in the case of excess chemical residues.

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Dust Pollution from Agronomics

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

Beefiness feedyards

Beef cattle are increasingly fed in confinement worldwide to capture economies of scale, increase the rate at which retail beefiness can be brought to market, and access markets for higher-grade beefiness cuts as compared with animals grazing pasture or rangeland. The The states is the leading producer of cattle for slaughter, merely Australia, Canada, Argentina, Brazil, and Mexico also take significant cattle-feeding industries. Developing countries in Asia, Africa, and South America are witnessing rapid growth in the beef sector as long-term dispensable income rises. Although it 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 corporeality of rainfall-driven wastewater that must be managed, controlled, and disposed. Every bit a result, open up-lot cattle feeding facilities tend to exist more prominent in semiarid to arid climates such equally the Great Plains and Southwest regions of the United States, the Prairie Provinces in Canada, and areas of Australia west of the Not bad Dividing Range in Queensland, New South Wales, and Victoria.

The principal prerequisite for the development of a growing cattle sector is the availability of feed grains either from local farming or imported past rail, ship, or truck. Feed grains are the principal 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 protein fraction) in fed-cattle diets may exist provided by byproducts such every bit processed root vegetables (due east.g., 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-beefiness cattle is thought to influence emission rates, airborne concentrations, and particle-size characteristics of grit.

Although the cattle are in solitude, excreted manure is deposited on the pen surface and the feed apron (which may be earthen or paved). Every bit the manure dries and is subjected to the animals' hoof action, it becomes part of the pen surface either as a well-compacted manure–soil matrix or equally a noncompacted layer of material dominated by manure solids. Under dry conditions, whatever mechanical disturbance of the noncompacted manure layer – whether past wind scouring, animal hoof action, or operation of heavy machinery, will generate dust particles and entrain them in the air. This dust, known equally fugitive grit or dust emitted from a diffuse or nonpoint source, consists primarily of dried manure particles but will as well include soil and waste material feed particles, creature dander, exhaust from low-cal vehicles and heavy machinery, grit from unpaved roads, and hair.

Fugitive dust emitted from a feedyard surface tends to exist 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 full suspended particulate (TSP) in fugitive feedyard dust, equally measured by high volume samplers, is in the range of 0.19–0.xl. Less is known well-nigh the relative abundance of fine particles (PM2.5) in feedyard dust, just contempo measurements suggest that the PM2.5/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 increase temporarily following atmospheric precipitation just return to original levels within days thereafter.

Avoiding dust emissions from cattle feedyards are usually expressed as emission fluxes (mass per unit of pen area per unit fourth dimension) or emission factors (mass per animal unit per unit time). These quantities are difficult to mensurate directly and are usually estimated by measuring dust concentrations both upwind and downwind of the source area. The measured dust concentrations are then input to a dispersion model to infer the emission flux that would take been required to generate the departure in measured concentrations. This indirect arroyo yields estimates of emission fluxes and emission factors that vary over an club of magnitude as shown in Table 1. The high uncertainty in values in Table 1 may be expected given the differences in climate, feedyard direction practices, feed composition, aerosol monitor performance, and dispersion-modeling algorithms across all studies.

Table ane. Published emission factors and/or fluxes of fugitive particulate thing from open-lot beef cattle feedyards

Citation Written report location Emission flux a (kg   ha−1 d−1) Emission factor b (g   per head   d−1)
PM2.5 PM10 Full suspended particulate (TSP) PM2.5 PM10 TSP
Peters and Blackwood (1977) California (USA) 6 29 114 fourteen 70 280
Parnell et al. (1999) Texas (U.s.) 0.6–0.8 iii–4 11–15 1.four–i.eight vii–9 28–36
Flocchini et al. (2001) California (U.s.) 1.five–six eight–31 33–122 4–15 xx–75 eighty–300
Wanjura et al. (2004) Texas (Usa) 1.5 8 31 iv xix 76
Lange et al. (2007) Texas (USA) 0.3–0.5 2–three 7–ten 0.eight–i.ii 4–6 sixteen–24
McGinn et al. (2010) Australia 3–5 13–25 51–98 6–12 31–threescore 124–240
Bonifacio et al. (2012) Kansas (Us) 2–iii 11–16 44–64 5–vi 27–30 108–120
a
Emission fluxes in this table are computed from the published emission factors on the basis of a nominal beast spacing of xiv   gii  per head. PM2.5 and PM10 are assumed to be 5% and 25% of TSP, respectively.
b
When main information sources for these columns were provided on an animal unit basis, we take converted them to a per-head ground past assuming 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, dense daytime cloud encompass, or atmospheric inversions – tends to favor higher footing-level concentrations. Even a short-term inversion may have a dramatic influence on ground-level PM concentrations, peculiarly when the inversion coincides with periods of increased animal activity and depleted surface moisture. Under those conditions, which are quite commonly observed virtually sunset in semiarid and arid climates, short-term (v   min to 1   h) concentrations of fugitive grit may increase 10–fifteen times college than the 24-hr average concentration (Effigy iv). Although the absolute values of those evening peak concentrations vary up to 2 orders of magnitude from day to day, the diurnal pattern (particularly in the summer) is remarkably consistent.

Figure iv. Typical daily variation of summer mass concentrations (v-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 moisture 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 wind erosion. To engagement, however, wind-driven emissions of dust from cattle feedyards remain a relatively unexplored research domain.

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Cattle priorities

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

5.4 Conclusions

Beef and dairy cattle are managed in a range of systems that vary in the level of dietary and infinite intensiveness. These systems are likely to meet 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 dispense their feed and select their diet, particularly to access roughage. Dietary preferences and resultant pick in cattle may be driven by palatability of different feedstuffs, notwithstanding, it can too be influenced by the need to rest nutrient intake, avoid toxins, and maintain rumen part. 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 wellness, is affected by water quality and its palatability, however, there is a need for more research investigating potential welfare and production consequences by providing free access to clean water.

Effigy 5.half-dozen. Summary of how different cattle direction systems meet the animals' dietary requirements and ability to move freely in high-quality space.

Astringent constraint of movement has negative effects on the welfare of cattle, whereas liberty to move is associated with good wellness and a range of normal behaviors, such every bit grooming. Both immature 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 movement tin can therefore exist considered a behavioral need of cattle. This motivation seems to build upwardly later on a relatively short period of severe confinement, however, research is needed to assess how the motivation to movement freely is influenced by housing systems that vary in their level of solitude, such as free-stall, drylot, and feedlot systems, that provide greater opportunities for movement than necktie-stalls, but non to the same extent as pasture-based systems. Similarly, more than work is too needed to understand the melancholia country of cattle in various housing systems.

Even though recent show has shown that cattle are highly motivated to access pasture, the choices animals brand depend on many different factors, such as where the feed is provided, weather conditions, time of 24-hour interval, and how far the animals take to walk to admission it. The motivation to access pasture is specially stiff at dark time and may propose that pasture is a more attractive place to lie downward on, possibly due to more infinite available and a more comfy lying surface. Does it accept to exist pasture? Whereas cattle seek opportunities to appoint in grazing and foraging behavior, there is to appointment no scientific evidence showing the strength of this motivation, and we encourage research in this area to be able to determine what it is virtually pasture that is attractive to cattle.

Finally, while in that location is evidence that cattle seek opportunities to graze and fodder, select their nutrition, in item to access roughage, and to be able to motility freely and access pasture to undertake unlike behavior activities, future research should as well address what it means to cattle to live in a complex environment with plenty of opportunities for option and control.

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