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 amount 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 draft purposes; however, it has been the assumption throughout this article that production of cattle for beef carcass markets is a primary goal. This article has not discussed many specific considerations involved in beef cattle production but has attempted to point out unique aspects of beef cattle production that might be different in other livestock species. General principles for breeding, genetics, nutrition, reproduction, health, and welfare are similar across livestock species, but specific knowledge and management within each species (as well as within combinations of animal resources, production environment, and local markets) are crucial for short-term as well 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 50% of its adult weight at approximately 12–15 months of age. The estrous cycle is regulated in a similar manner to other mono-ovulatory species with the preparation of the uterus for successful pregnancy irrespective of whether or not an embryo is present. The embryo undergoes a period 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 breed and sex of the foetus. Parturition is similar as in dairy cattle, but beef cattle do not experience the post-partum negative 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.g., 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 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
Ovulation type 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 stage 4–8 cell stage 2-cell stage 4–8 cell stage
Completion of X-Chromosome inactivation Post-blastocyst Possibly blastocyst Post-blastocyst Blastocyst Blastocyst
Elongation rate Rapid Rapid Extremely rapid N/A N/A
Pregnancy recognition signal 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 beef cattle in intensive and extensive production systems

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

Conclusion

Beef cattle are unique, compared to poultry and swine in that they can convert low-quality forages into high-quality protein for humans. Recently, there has been growing pressure to globally restrict beef production, due to its perceived negative impact on the environment. Beef 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 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, so as to avoid 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 climate change and the scarcity of new tracts of pasture and arable land, sustainable intensification will be the only means of satisfying demand. Intensified systems will need to increase the use of by-product feeds and food wastes in beef cattle production. Nutrient management plans will be needed to ensure that nutrient flows are aligned with the principals of a circular 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 beef is to be produced on less land. 93 , 95

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Methods to measure body composition of domestic animals

Steven M. Lonergan , ... Dennis N. 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 usually used in beef cattle rather than a small ruler that is used in pigs (Fig. 8.15). The needle probe is more effective 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 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 three layers of subcutaneous fat so the person entering the needle probe in cattle must develop a technique so the aponeurosis connective tissue is penetrated but not 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 adjust 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 indicate that there can also be a twofold difference in hide thickness among cattle. Once the fat thickness is recorded, it can also be used for prediction equations to estimate percentage fat and muscle in the beef carcass.

Fig. 8.15

Fig. 8.15. An example of the needle probe used for estimating fat thickness in beef 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 Animal Biotechnology, 2014

Beef Cattle Selection

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 complex traits. Recent advancements in sequencing and genotyping technologies have enabled a rapid evolution 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 have become available for beef producers to efficiently produce high quality beef for today's consumer. Technologies such as next 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 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 data 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 important, and their knowledge will allow testing across breeds, which will drastically reduce the number of loci that need to be 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

Abstract

Beef cattle production is done within a system 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 so that animals are sold for food 2-3 years from the time they were conceived; and, in most situations, more 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

Beef cattle, and more recently dairy cattle, in the United States are routinely fed a class of antibiotics known as ionophores, and these compounds decrease H 2 and CH4 production and increase propionate and energy retention. Obligate amino acid-fermenting ruminal bacteria are also sensitive to ionophores, and this inhibition decreases NH3 production and conserves amino acids. Some lactic acid-producing bacteria are inhibited by ionophores, and this activity may modulate ruminal pH.

Ionophores translocate ions across cell membranes. When ion gradients (e.g., 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 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 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 can adapt. Ionophore resistance now appears to be mediated by extracellular polysaccharides (glycocalyx) that excludes hydrophobic ionophore molecules from the cell membrane.

In 2006, the European Union banned the use of antibiotics, including ionophores, in animal feed as growth promotants. Some questions then arise. How safe are ionophores? Do ionophores increase resistance to therapeutic antibiotics? Should they be banned in the United States as well? This is a very controversial subject, but some facts can be cited: (1) ionophores have and never will be used in human medicine due to toxicity; (2) cattle not receiving ionophores always have large populations of ionophore-resistant bacteria; (3) the increase in ionophore-mediated resistant bacteria is quickly reversed as soon as the ionophore is removed from the diet; (4) ionophore resistance appears to be a physiological selection 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 cause an increase in resistance to 20 therapeutic antibiotics; and (6) ionophores have been very widely used for more than 20 years in the United States, and there has been little change in their effect on the feed efficiency of cattle.

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Modelling beef cattle production to improve quality

K.G. 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 by various classes of animals in a beef cattle herd to give meat for human consumption. This beef production system consists of four 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 various subsystems are described in more detail below.

Fig. 12.1. Interrelationships between biophysical and bioeconomic subsystems (rectangles) with the management subsystem of the farmer. The biophysical and bioeconomic subsystems contain processes that determine 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, animal and economic subsystems.

The climate subsystem is largely outside the management subsystem but it directly affects the four subsystems influenced by a manager. For example, rainfall supplies soil water for plant 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 display 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 big challenge for a farm manager. 12 Seasonal variations in climate give rise to seasonal variations in quality and type of forage which may trigger fodder conservation (e.g. hay) to offset periods of forage deficiency. wide year-by-year variations in climate inputs, often expressed as droughts or floods which lead to major perturbations in forage supply and market prices, need to be handled through skillful and resourceful management. 13 However, long-term weather forecasts now give managers prior warning of likely climatic extremes. For example, in northern 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 likely distribution of rainfall. 14 Also extremely hot or cold temperatures can cause deaths in plants and animals, and computer models such as GRAZ- PLAN, 15 coupled to weekly weather forecasts, give early warning 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 water and nutrients for plant growth. Since it includes many of the ecological processes that sustain the whole system, both the manager and interest groups in the wider community are keen to keep the land subsystem in good condition. Land degradation through soil erosion, desertification, salinisation, acidification and nutrient decline is a major concern in many of the world's 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. Landscape management also recognises that grazing lands produce food as well as ecosystem services, such as water and biodiversity that are needed to sustain the cities where most people live. Preferred management strategies for a landscape may arise through different management options being assessed by government agencies or local communities, and computer models are often useful tools in this process. 16

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, return to the soil subsystem through the detritus food chain. The quality of forage on offer varies with the growing conditions and type of plant species in the system. New growth is the most digestible and there is a steady decline in quality as plant parts age, die and senesce. Since temperate grasses have a higher digestibility than tropical grasses, grazing systems in temperate zones tend to display higher animal performance than tropical zones, Leguminous species tend to have higher digestibility than gramineous species. 17 If a grazing system 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 particular situation. This contrasts with native rangelands where the system consists of many different species, often including trees. Here a manager aims to keep the pasture in good condition by maintaining adequate plant cover to reduce soil erosion and a predominance of desirable rather than undesirable plant species. 18 In both sown pasture production systems and native rangelands, forage condition and animal performance can be manipulated by management options such as the choice 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 , 20

The cattle subsystem produces animals for sale through the processes of reproduction and growth within a herd consisting of different animal 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, breeding cows produce calves and after weaning these move into different classes as they grow and age (Table 12.1). Usually young female cattle (heifers) are selected to replace aged or culled cows and are mated for the first time when they reach maturity and a specific weight that depends on the breed and prevailing nutrition. 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 not required for replacing cows might be sold for slaughter or for breeding purposes elsewhere. Male cattle are commonly castrated before weaning although a small number of high-performing males may be retained to replace aged bulls. Depending on the prevailing nutrition and markets, male cattle may be retained for one to three years after weaning, to be 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 key 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 class to the energy requirement of an adult animal, is a coefficient for equating animal 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

Animal class Adult equivalent Age years Comments
Cows and calves 1.3 2-12 Managers aim to have 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-year-old heifers 0.75 1.5-2.5 breed and growing conditions, 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. Age and weight at
2-year-old steers 0.8 1.5-2.5 sale depends on the level of nutrition they experience, the specifications of available markets, and
3-year-old steers 1.0 2.5-3.5 on the price advantage of different markets. Within limits set by prevailing climatic and
4-year-old steers 1.1 3.5-4.5 economic conditions, a manager can 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 1.1 3-7 Male animals for mating with cows. One bull is required for every 20 to 25 cows.

The different classes of cattle in a beef herd have different nutritional requirements because they differ in weight and age. The term adult equivalent (AE) relates the energy requirement of different classes to a common base, 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 but 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/head. 21

The market subsystem refers to the different markets for beef cattle available to a manager along with the prices and 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 beef 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 grade. Farmers in countries that export beef, such as USA, 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 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 case of excess chemical residues.

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Dust Pollution from Agriculture

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

Beef feedyards

Beef 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-grade beef cuts as compared with animals grazing pasture or rangeland. The United States is the leading producer of cattle for slaughter, but Australia, Canada, Argentina, Brazil, and Mexico also 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 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 amount of rainfall-driven wastewater that must be managed, controlled, and disposed. As a result, 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 Great Dividing Range in Queensland, New South Wales, and Victoria.

The primary 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 scale of food-processing or biofuel-processing industries nearby, the concentrate (or energy and protein fraction) in fed-cattle diets may be provided by byproducts such as processed root vegetables (e.g., potatoes and beets) or spent grains (e.g., 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 apron (which may be earthen or paved). As 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 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 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 but will also include soil and waste feed particles, animal dander, exhaust from light vehicles and heavy machinery, dust from unpaved roads, and hair.

Fugitive dust 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 (PM2.5) in feedyard dust, but recent 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 precipitation but return to original levels within days thereafter.

Fugitive dust emissions from cattle feedyards are usually expressed as emission fluxes (mass per unit of pen area per unit time) or emission factors (mass per animal unit per unit time). These quantities are difficult to measure 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 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 high uncertainty in values in Table 1 may be expected given the differences in climate, feedyard management practices, feed composition, aerosol monitor performance, and dispersion-modeling algorithms across all studies.

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

Citation Study location Emission flux a (kg   ha−1 d−1) Emission factor b (g   per head   d−1)
PM2.5 PM10 Total suspended particulate (TSP) PM2.5 PM10 TSP
Peters and Blackwood (1977) California (USA) 6 29 114 14 70 280
Parnell et al. (1999) Texas (USA) 0.6–0.8 3–4 11–15 1.4–1.8 7–9 28–36
Flocchini et al. (2001) California (USA) 1.5–6 8–31 33–122 4–15 20–75 80–300
Wanjura et al. (2004) Texas (USA) 1.5 8 31 4 19 76
Lange et al. (2007) Texas (USA) 0.3–0.5 2–3 7–10 0.8–1.2 4–6 16–24
McGinn et al. (2010) Australia 3–5 13–25 51–98 6–12 31–60 124–240
Bonifacio et al. (2012) Kansas (USA) 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 animal spacing of 14   m2  per head. PM2.5 and PM10 are assumed to be 5% and 25% of TSP, respectively.
b
When primary data sources for these columns were provided on an animal unit basis, we have converted them to a per-head basis by 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 cover, or atmospheric inversions – tends to favor higher ground-level concentrations. Even a short-term inversion may have a dramatic influence on ground-level PM concentrations, especially when the inversion coincides with periods of increased animal activity and depleted surface moisture. Under those conditions, which are quite commonly observed near sunset in semiarid and arid climates, short-term (5   min to 1   h) concentrations of fugitive dust may increase 10–15 times higher than the 24-hour average concentration (Figure 4). Although the absolute values of those evening peak concentrations vary up to 2 orders of magnitude from day to day, the diurnal pattern (especially 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 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 wind 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

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. 5.6. 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, it can also be influenced by the need to balance nutrient intake, avoid toxins, and maintain rumen function. Further research is needed to determine how changing physiological demands associated with growth, lactation, and pregnancy may influence dietary selection across 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, there is a need for more research investigating potential welfare and production consequences by providing free access to clean water.

Figure 5.6. Summary of how different cattle management systems meet 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 grooming. Both young and adult dairy cattle are highly motivated to be able to move freely and to undertake other behavioral activities, such as self-grooming, exploration, and play. Freedom of movement can therefore be considered a behavioral need of cattle. This motivation seems to build up after a relatively short period of severe confinement, however, research is needed to assess 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 movement than tie-stalls, but not to the same extent as pasture-based systems. Similarly, more work is also needed to understand the affective state of cattle in various housing systems.

Even though recent evidence has shown that cattle are highly motivated to access pasture, the choices animals make depend on many different factors, such as where the feed is provided, weather conditions, time of day, and how far the animals have to walk to access it. The motivation to access pasture is particularly strong at night time and may suggest that pasture is a more attractive place to lie down on, possibly due to more space available and a more comfortable lying surface. Does it have to be pasture? Whereas cattle seek opportunities to engage in grazing and foraging behavior, there is to date no scientific evidence showing the strength of this motivation, and we encourage research in this area to be able to determine what it is about pasture that is attractive to cattle.

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

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