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Poultry are sensitive to red objects, such as comb and blood on the body surface, likely inducing injurious pecking in flocks. Light is an important factor that affects the pecking behavior of poultry. A wooden box was built to investigate the effects of Light Emitting Diode (LED) light color (warm white and cold white) and intensity (5 and 50 lux) of background light on the discrimination of red objects in broilers. A piece of red photographic paper (Paper 1) was used to simulate a red object and paired with another piece of paper (Paper 2 to 8) with a different color. Bigger number of the paired paper indicated greater color difference. The experiment consisted of three phases: adaptation, training, and test. In the adaptation phase, birds were selected for the adaptation to reduce the stress from the box. In the training phase, birds were trained to discriminate and peck at Paper 1 when paired with Paper 8 under one type of background light. Twenty-three birds were tested when the paired paper was changed from Paper 7 to 2. Each pair of paper included 12 trials for every bird, and response time to peck and proportion of choices of Paper 1 in the last 10 trials were collected. The results showed that broilers tested under 5 lux light had longer response times than broilers tested under 50 lux light (P < 0.05). When Paper 1 was paired with paper 7, broilers tested under warm white light had lower proportion of choices of Paper 1 than those tested under cold white light (P < 0.05). Color difference had a significant effect on response time of broilers (P < 0.05). Moreover, the proportion of choices of Paper 1 decreased to 50% (chance-level performance) when color of the paired paper was gradually similar to Paper 1. Conclusively, rearing broilers in warm white rather than cold white light with appropriate light intensity should be recommended to reduce damaging pecking behavior in broiler production. [ABSTRACT FROM AUTHOR]

Measurement of nutrient digestibility is a key pillar in estimating the value of feeds for livestock. Conditions are not always amendable to estimating feed digestibility through total collection methods, and as a result digestibility markers are frequently employed. The first “Digestibility markers” were reported in the early 1900s where colored glass beads were used to estimate the flow of digesta through the digestive tract. Subsequently, a myriad of digestibility markers has been assessed with the internal markers; acid insoluble ash, acid detergent lignin, indigestible neutral detergent fiber and n-alkanes and the external markers titanium dioxide and chromic oxide being the most common. Chromic oxide (Cr2 O3) was first proposed as a digestibility maker in 1918 and continues to be widely used in modern day metabolism, confined performance and grazing livestock experiments. It was the demand to use chromic acid as a digestibility marker that led Terry and Mira Fenton to publish the article “An improved procedure for the determination of chromic oxide in feed and feces” in the Canadian Journal of Animal Science in 1979. This became the most cited article in the history of the journal with over 800 citations. The procedure eliminated the use of nitric acid in a pre-digestion step and ashing reduced the organic matter content, making it less likely that perchloric acid would be converted to anhydrous perchloric acid which poses an explosive hazard. The procedure continues to be widely used to measure Cr2 O3 as a digestibility marker and has made a significant contribution to our assessment of the value of a wide range of feeds for Canadian livestock. [ABSTRACT FROM AUTHOR]

Forage-animal production agriculture is implementing infrastructure changes and management strategies to adjust to increased energy-related costs of fuel, feed grains, fertilizers, and seeds. The primary objectives of this position paper are to assess future research and extension scientific needs in forage utilization, financial support for the discipline, and changing status and number of scientists. A survey questionnaire returned from 25 land-grant universities in the eastern half of the United States rated the top 4 research needs as 1) pasture systems and efficiency of production; 2) interfacing with energy concerns; 3) forage cultivar evaluations and persistence; and 4) environment impacts. Plant-animal future research needs at 11 USDA-ARS regional locations are targeted at sustainable management and improved livestock performance, ecophysiology and ecology of grasslands, environment impacts, and improved technologies for nutritive value assessments. Extension scientists from 17 southern and northeastern states listed the top 3 needs as forage persistence, soil fertility and nutrient management, and pasture systems and efficiency of production. Grant funds currently provide more than 40% of land-grant university research and extension efforts in forage utilization, and scientists estimate that this support base will increase to 55 to 60% of the funding total by 2013. Reduced allocation of state and federal funding has contributed to a reduction in the number of full-time equivalent (FTE) scientists engaged in forage utilization research and extension activities. The current 25 state FTE conducting research number about 2.8 per state. This includes 10 states with >3, 11 states with <2, and 3 states with <1 FTE. Increased interest in cellulosic energy, climate change, and environmental impact may offer new opportunities for these FTE to participate in integrated cross-discipline research Extension programming, and technology transfer methods will change to accommodate reduced funding but with increasing numbers of novice, recreation-oriented landowners. [ABSTRACT FROM AUTHOR]

Teaching has a long and varied history in the life of departments of animal science and the American Society of Animal Science. Some of the earliest reports from meetings of the society have strong indication that planning the curriculum was a prominent feature of the meetings. Teaching symposia were also included almost from the beginning. The society went through a lengthy period from the 1940s through most of the 1960s when teaching was not a prominent focus, but a symposium in 1968 appeared to be a catalyst for change, and, since that date, teaching has again been an important part of the meetings. In recent years, out- standing symposia and contributed papers have made the teaching section a vibrant entry. Departments of animal science have changed considerably since the early days in which "men taught boys" and the primary goal was to produce farmers. More female students, more urban students, interest in a wide variety of animals, and greatly diversified career goals have been emerging during the last few decades. Departments of animal science and the American Society of Animal Science are positioning to be able to respond to change and face the challenge of providing excellence in teaching during the next century. [ABSTRACT FROM AUTHOR]

Recycled paper products were compared with straw (STR) as bedding in two 4 wk trials with Holstein heifers in a loose housing system. Pens consisted of a scrape alley (3.0 x 3.6 m) and bedded pack (3.6 x 4.6 m). In Trial 1, eight pens of 5 heifers (average weight 320 kg) were bedded with STR or hammer-milled newspaper (HNP; 2.54 cm screen). In Trial 2, six pens of 38 heifers (6-7 animals/pen; average weight 211 kg) were bedded with STR, shredded newspaper (SNP), or shredded office paper (SOP). Initial bedding provided a 5.08 cm cushion for a lying heifer. Moisture content of bedded pack was recorded daily using an 81.3 cm Farmex® probe and clean bedding added if moisture exceeded 30%. Heifer cleanliness (scale 1 clean to 5 dirty) was recorded on Days 0, 7, 14, 21, and 28. Heifer behavior was recorded once daily as location (scrape alley, bedded pack) and position (lying, standing). Bedded packs were sampled on Day 28 for nutrient content. Data were analyzed using repeated measures or ANOVA using NCSS® software. Moisture content of bedded packs increased with day (P < 0.05) but did not differ with bedding type (Trial 1: 37.6%; Trial 2: 42.6 - 43.5%). Amount of bedding used per pen differed (P < 0.05) with bedding type (Trial 1: STR 164 kg, HNP 179 kg; Trial 2: STR 443 kg, SNP 464 kg, SOP 334 kg) due to density. Cleanliness scores increased (P < 0.05) with Day in Trial 1, but decreased (P < 0.05) in Trial 2. Bedding type influenced (P < 0.05) cleanliness score (Trial 1: STR 1.7, HNP 1.6; Trial 2: STR 2.8, SNP 2.3, SOP 2.5). Ammonia-N content of bedded pack differed (P < 0.05) with bedding type in Trial 2 (STR 0.098%, SOP 0.017%, SNP 1.96%). The pH content of clean bedding (STR 6.8, SNP 7.7, SOP 9.9) was a factor. Bedding type did not affect heifer behavior (P < 0.05). These experiments suggest that use of paper products compared to STR result in cleaner animals; however, amounts used and waste content can vary with bedding type or processing of paper product. [ABSTRACT FROM AUTHOR]

From a historical perspective, it is difficult to identify a specific date that launched the field of endocrinology. One "biomarker" of the inception of endocrinology traces back to Ernest Henry Starling, who first introduced the word hormone in a talk given in 1905 at the Royal College of Physicians in London (Starling, 1905). A historical look at the field of endocrine regulation of animal growth since 1905 conveys that countless scientists worldwide worked to advance the scientific evidence base, which led to the commercial development of hormone-based products that enhanced growth and beneficially changed carcass composition of meat animals. This review will discuss some of seminal contributions that include the discovery of hormones (like ST and β-adrenergic agonists) that have been shown to play key roles in regulating growth and nutrient partitioning of livestock, the mechanisms by which these hormones act, and the development of products for application in animal agriculture. [ABSTRACT FROM AUTHOR]

Compared with the more traditional sciences of nutrition, physiology, and reproduction, the acceptance of animal welfare science in its own right is still relatively new. Seven colleagues, who had an average of 10 yr experience with beef (n = 5), swine (n = 5), dairy (n = 2), poultry (n 1), and sheep (n = 1) were asked several questions on the opportunities and challenges facing the field. The information collected was pooled for anonymity. General challenges identified by the group were (1) are we making progress and how can this be defined, (2) demand for information has outpaced the science, and (3) pressures from stakeholders. Solutions were (1) to continue providing sound science that has been validated, measured objectively, and is reliable; and (2) to continue to have animal science and veterinary medicine departments employ faculty trained in farm animal welfare. Highlights for the future were willingness for animal welfare scientists to work across disciplines and across departments, within the same institution, and enthusiastically across state lines; and expansion of new teaching models, in conclusion, new and innovative tools, personalities, and dedication to the field of animal welfare will continue to provide scientific information and direction for farm animal welfare science. [ABSTRACT FROM AUTHOR]

Knowledge of general aspects of mammary gland function, including metabolic pathways and hormonal regulation of mammary gland development and lactation, in livestock species was obtained several decades ago. As basic biological information of growth factor action, apoptotic mechanisms, and signal transduction events has exploded, the mouse became the model of choice for studying fundamental mechanisms regulating mammary function. A complete sequenced genome also has made the mouse amenable for studies of mammary gene network expression. Advances in molecular biology techniques currently allow researchers to genetically modify mice to either overexpress or completely lack specific genes, thereby studying their function in an in vivo setting. Furthermore, the use of mammary-specific promoters has allowed genes related to mammary gland function to be eliminated from the mammary gland in a developmental and tissue-specific manner. These studies have demonstrated the complexity that underlies mammary gland development and function in rodents and may provide insight into the mechanisms that ultimately allow the ruminant or swine mammary gland to function in a coordinated fashion throughout puberty, pregnancy, lactation, and involution. The challenge facing animal scientists is how to obtain similar information in much larger and expensive livestock. One possible approach is to manipulate gene expression in vitro using mammary cell culture models derived from domestic animals (e.g., genes can be "knocked down" using small interfering RNA approaches). Ultimately, major advances in understanding lactation biology may come from coupling basic mechanistic information with functional genomics, proteomics, and metabolomics approaches. A strong foundation in bioinformatics will also be required to optimize use of these new technologies. Stem cell biology also represents an exciting area in the next decade that holds promise for improving lactation efficiency. Strong training of our future scientists in these areas should facilitate livestock-focused mammary gland research that will allow basic information to be gained at unprecedented amounts, ultimately leading to optimization of livestock production. [ABSTRACT FROM AUTHOR]

The past century has seen animal breeding and genetics evolve and expand from definition and validation of basic population genetics theory to development of selection index theory to today's relatively sophisticated genetic prediction systems enabling industry genetic improvement. The end of the first century of the American Society of Animal Science coincides with the rapid movement of the field into the era of genome-enabled genetic improvement and precision management systems. Led by recent research infrastructure investments by the United States and international partners to develop chicken, bovine, swine, ovine, and equine "genomic toolboxes," the animal breeding community is poised to play a crucial role in the century to come. These genomic toolboxes provide the needed platforms for developing whole-genome selection programs based on linkage disequilibrium for a wide spectrum of traits; allow the opportunity to redefine genetic prediction based on allele sharing as opposed to traditional pedigree relationships; and provide for the first time simultaneous information upon which to practice genetic selection and plan precision management of specific genotypes, all early in the life of the animal. An area of major focus will be mining of the genomes through systems biology approaches to better understand gene and metabolic networks—what has previously been lumped into poorly understood genotype by environment and genotype by genotype interactions. Perhaps the greatest obstacle to the successful merger of genomic and quantitative approaches will be the lack of necessary animal resource populations to appropriately define and measure phenotypes (i.e., the so-called phenomic gap) for difficult-to-measure traits such as resistance to disease and stress, adaptability, longevity, and efficiency of nutrient utilization. Additionally, because of de-emphasis of quantitative genetics and animal breeding programs in academia over the past quarter century, a dearth of qualified young scientists to effectively mine the genomes must immediately he addressed. Although the motivating factors may have changed, the need for high-quality animal breeding and genetics research and education has never been greater. [ABSTRACT FROM AUTHOR]

Departments of animal sciences must be relevant to a society in which a small number of people can raise almost all the food animal products needed. The declining number of people involved in animal agriculture has decreased enrollment of students interested in food animals in many departments of animal science. However, several departments welcomed students from a diverse background and began research on animals other than food animals. In many states, the undergraduate enrollment is made up primarily of students interested only in companion animals. A benefit of this is that we have recruited new students into animal agriculture and they have gone on to excellent careers. We have a new challenge now: how to maintain and expand the efforts in teaching, research, and outreach of companion animal science. Departments wishing to expand in teaching have examples of successful courses and curricula from other departments. Some departments have expanded their teaching efforts across their own university to teach about pets to a wider audience than their own majors; other departments can follow. In research, a small number of faculty have been able to establish extramurally funded projects on pets, including horses. But it will be difficult for more than a handful of departments to have a serious research effort in dogs, cats, birds, fish, or exotic animals. Departments will have to make a concerted effort to invest in such endeavors; joint ventures with other universities and colleges of veterinary medicine (or medicine) will probably be required. Funding sources for "traditional" efforts in nutrition, reproduction, and physiology are small and inconsistent; however, with the progress of the equine, canine, and feline genome projects, there should be opportunities from federal funding sources aimed at using animal models for human health. In addition, efforts in animal behavior and welfare can be expanded, perhaps with some funding from private foundations or animal-supportive organizations. [ABSTRACT FROM AUTHOR]

Goat research in the United States has increased but at a rate less than that in production. Research on goat meat includes nutritional quality, packaging, color, sensory characteristics, and preslaughter management. Goat skins have value for leather, but quality of goat leather has not been extensively studied. Research in the production, quality, antibiotic residues, and sensory characteristics of goat milk and its products has aided development of the US dairy goat industry. Limited progress has been made in genetic improvement of milk or meat production. There is need to explore applications of genomics and proteomics and improve consistency in texture and functionality of goat cheeses. New goat meat and milk products are needed to increase demand and meet the diverse tastes of the American public. Despite research progress in control of mohair and cashmere growth, erratic prices and sale of raw materials have contributed to further declines in US production. Innovative and cooperative ventures are needed for profit sharing up to the consumer level. Internal parasites pose the greatest challenge to goat production in humid areas largely because of anthelmintic resistance. Study of alternative controls is required, including immunity enhancement via nutrition, vaccination, pasture management such as co-grazing with cattle, and genetic resistance. Similarly, the importance of health management is increasing related in part to a lack of effective vaccines for many diseases. Nutrition research should address requirements for vitamins and minerals, efficiencies of protein utilization, adjusting energy requirements for nutritional plane, acclimatization, and grazing conditions, feed intake prediction, and management practices for rapid-growth production systems. Moreover, efficient technology transfer methods are needed to disseminate current knowledge and that gained in future research. [ABSTRACT FROM AUTHOR]

Animal breeding reports in the Journal of Animal Science (JAS) and in its predecessor, Proceedings of the American Society of Animal Production, were counted and categorized. In 22 volumes of the Proceedings of the American Society of Animal Production, 155 articles had animal breeding content, of which 54% were research reports, 17% extension communications, and 28% syntheses or reviews. Several of the latter featured advice from the livestock industry to the scientific community. Thirty-one percent of articles concerned swine, whereas beef cattle, dairy cattle, and sheep each accounted for an additional 20%. In the 67 yr of JAS publication, 3,045 research papers were identified with animal breeding content, nearly half of them published since 1990. Growth in publication output was modest during the 1950s, robust in the 1960s through 1980s, moderate in the 1990s, and static in the 2000s. Important topics included genetic resource evaluation (a subject in 55% of all manuscripts), genetic parameter estimation, selection programs, and nonrandom mating systems. Maternal effects and genotype × environment interactions were featured in 17 and 15% of all manuscripts, respectively, whereas 6% dealt with a simply inherited trait. Only 4% of manuscripts included economic analysis of a breeding program or intervention. Interest in molecular biology and biometry has surged in the 1990s and 2000s. Approximately 50% of all papers involved cattle, a fifth of which concerned dairy cattle or beef × dairy crossbreds. A quarter of papers concerned swine, 15% concerned sheep, and 3% considered laboratory rodents, with the proportional contribution of sheep research decreasing across time. Authors from the Midwestern and Southern sections of the American Society of Animal Science had greater proportional contributions than Western and Northeastern section authors, and contributions of university and state experiment station authors outnumbered those of USDA-ARS authors. The proportional contribution of international authors increased across time, reaching 45% for the 2000s, as that of university and experiment station authors decreased and that of USDA-ARS authors remained fairly constant. Subjective analysis suggested substantial levels of creativity, innovation, and cooperation in JAS animal breeding research, a strong international perspective, but also a marked degree of imitation and repetition in subject matter content. [ABSTRACT FROM AUTHOR]

Measuring dairy cattle methane (CH4) emissions using traditional recording technologies is complicated and expensive. Prediction models, which estimate CH4 emissions based on proxy information, provide an accessible alternative. This review covers the different modeling approaches taken in the prediction of dairy cattle CH4 emissions and highlights their individual strengths and limitations. Following the guidelines set out by the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA); Scopus, EBSCO, Web of Science, PubMed and PubAg were each queried for papers with titles that contained search terms related to a population of "Bovine," exposure of "Statistical Analysis or Machine Learning," and outcome of "Methane Emissions". The search was executed in December 2022 with no publication date range set. Eligible papers were those that investigated the prediction of CH4 emissions in dairy cattle via statistical or machine learning (ML) methods and were available in English. 299 papers were returned from the initial search, 55 of which, were eligible for inclusion in the discussion. Data from the 55 papers was synthesized by the CH4 emission prediction approach explored, including mechanistic modeling, empirical modeling, and machine learning. Mechanistic models were found to be highly accurate, yet they require difficult-to-obtain input data, which, if imprecise, can produce misleading results. Empirical models remain more versatile by comparison, yet suffer greatly when applied outside of their original developmental range. The prediction of CH4 emissions on commercial dairy farms can utilize any approach, however, the traits they use must be procurable in a commercial farm setting. Milk fatty acids (MFA) appear to be the most popular commercially accessible trait under investigation, however, MFA-based models have produced ambivalent results and should be consolidated before robust accuracies can be achieved. ML models provide a novel methodology for the prediction of dairy cattle CH4 emissions through a diverse range of advanced algorithms, and can facilitate the combination of heterogenous data types via hybridization or stacking techniques. In addition to this, they also offer the ability to improve dataset complexity through imputation strategies. These opportunities allow ML models to address the limitations faced by traditional prediction approaches, as well as enhance prediction on commercial farms. [ABSTRACT FROM AUTHOR]

In an era in which academic institutions are held more accountable, a problem, which does not seem to have an immediate resolution, exists: how does one demonstrate the quality of one's work? Specifically, how does one show that his or her research is making an impact and is thought to be important? A variety of measures of scientific journal article importance, reflected mostly by citation analyses, have been focused on as being potential gold standards. However, although several measures have been reported, keeping a record of citation of individual research papers, primarily due to the effort involved in finding accurate information, is not for wimps. [ABSTRACT FROM AUTHOR]

A total of 1,628 papers presented at the sixth and seventh World Congresses on Genetics Applied to Livestock Production were categorized into 20 topics according to research subjects. The aim was to determine, in relation to various topics in animal breeding and genetics, the forms of partnerships and the degree of attention given in different continents. North-North partnerships (defined as cooperation between and within developed countries) had a 68.80% representation of research papers presented, whereas North-South partnerships (cooperation between developed and developing countries) had the least representation with only 8.23% of papers. Asia contributed the most research papers in biochemical genetics, whereas Australia lead in research papers on breeding for fiber and fur. Europe contributed the most to the remaining topics, and Africa usually, but not always, contributed the least to most research topics. This study provided a useful indication of the current state of literature in animal breeding and genetics and will be useful to animal breeding and genetics researchers worldwide as they chart the way forward for research and development in the field of genetics applied to livestock production in different continents. [ABSTRACT FROM AUTHOR]

Automated Milking Systems (AMS) have undergone significant evolution over the past 30 yr, and their adoption continues to increase, as evidenced by the growing scientific literature. These systems offer advantages such as a reduced milking workload and increased milk yield per cow. However, given concerns about the welfare of farmed animals, studying the effects of AMS on the health and welfare of animals becomes crucial for the overall sustainability of the dairy sector. In the last few years, some analysis conducted through text mining (TM) and topic analysis (TA) approaches have become increasingly widespread in the livestock sector. The aim of the study was to analyze the scientific literature on the impact of AMS on dairy cow health, welfare, and behavior: the paper aimed to produce a comprehensive analysis on this topic using TM and TA approaches. After a preprocessing phase, a dataset of 427 documents was analyzed. The abstracts of the selected papers were analyzed by TM and a TA using Software R 4.3.1. A Term Frequency-Inverse Document Frequency (TFIDF) technique was used to assign a relative weight to each term. According to the results of the TM, the ten most important terms, both words and roots, were feed, farm, teat, concentr, mastiti, group, SCC (somatic cell count), herd, lame and pasture. The 10 most important terms showed TFIDF values greater than 3.5, with feed showing a value of TFIDF of 5.43 and pasture of 3.66. Eight topics were selected with TA, namely: 1) Cow traffic and time budget, 2) Farm management, 3) Udder health, 4) Comparison with conventional milking, 5) Milk production, 6) Analysis of AMS data, 7) Disease detection, 8) Feeding management. Over the years, the focus of documents has shifted from cow traffic, udder health and cow feeding to the analysis of data recorded by the robot to monitor animal conditions and welfare and promptly identify the onset of stress or diseases. The analysis reveals the complex nature of the relationship between AMS and animal welfare, health, and behavior: on one hand, the robot offers interesting opportunities to safeguard animal welfare and health, especially for the possibility of early identification of anomalous conditions using sensors and data; on the other hand, it poses potential risks, which requires further investigations. TM offers an alternative approach to information retrieval in livestock science, especially when dealing with a substantial volume of documents. [ABSTRACT FROM AUTHOR]

Meat has been important to human survival and personal enjoyment for thousands of years, and as societies become more affluent, the amount and quality of meat consumed increases. Ancient Egyptians are known to have consumed ground meat, whereas the Greeks and Romans enjoyed various types of sausages. Ground meat has been consumed throughout the world under various names and for several centuries. However, in recent years, microbial meat safety has become a major concern, and it appears that meat safety challenges will persist in future years. This paper provides a brief historical account of selected developments in microbiology, meat science, and safety, and associated industrial and regulatory highlights, and a brief overview of current and future food safety issues, concerns, and challenges. [ABSTRACT FROM AUTHOR]

During this centennial year of the American Society of Animal Science (ASAS), it is of interest to look back over the history of our Society and, in particular, to the many contributions made by researchers in the area of swine nutrition. A great number of basic and applied research studies involving the nutrition of weanling, growing, and finishing pigs, and gestating and lactating sows have been conducted by swine nutritionists during the past 100 yr. Most of these studies were conducted at universities by animal scientists or by the graduate students under their leadership. Others were conducted by nutritionists in the feed and pharmaceutical industries and government scientists at ARS/USDA research centers. Contributions were also made by animal scientists beyond our borders. Much of the research was published in the Journal of Animal Science during its 66 yr of existence. Before the first issue of the journal was published in 1942, some of the earlier studies were reported in the Proceedings of the Annual Meeting of the Society of Animal Production, the forerunner of ASAS. These research studies have progressively led to a better understanding of the role and utilization of dietary energy, protein, AA, carbohydrates, fats, minerals, and vitamins by pigs and have helped to quantify the nutrient requirements of pigs for various stages of growth, for sows during gestation and lactation, and to a limited extent, for boars. Determining the nutritional value of a wide array of feedstuffs, evaluating feeding strategies, and assessing the value of growth-promoting and carcass-enhancing agents have been important research contributions as well. To identify the particular studies that were among the most instrumental in contributing to our present knowledge of swine nutrition is, to say the least, a daunting assignment. To aid in this task, a survey of swine nutritionists was conducted in which they were asked to identify and rank the 10 most significant findings in swine nutrition during the past 100 yr. The results of that survey are presented in this paper. [ABSTRACT FROM AUTHOR]

Acute and subacute ruminal acidosis, bloat, liver abscesses, and polioencephalomalacia (PEM) were reviewed with respect to contributions published in the Journal of Animal Science (JAS) regarding these metabolic and digestive disorders in beef cattle. Increased grain feeding and expansion of the feedlot industry in the 1960s led to considerable research on acidosis, and. early publications defined ruminal changes with acute acidosis. The concept of subacute acidosis was developed in the 1970s. Significant research was published during the 1980s and 1990s on adaptation to high-grain diets, effects of ionophores, and the development of model systems to study ruminal and metabolic changes in acidosis. Since 2000, JAS publications on acidosis have largely focused on individual animal variability in response to acid loads and the role of management strategies in controlling acidosis. Increased grain feeding also was associated with an increase in the incidence of liver abscesses, which were quickly linked to insults to the ruminal epithelium associated with acidosis. The role of antibiotics, particularly tylosin, in decreasing the incidence and severity of liver abscesses was a significant contribution of JAS publications during the 1970s and 1980s. Papers on bloat were among the earliest published in JAS related to metabolic and digestive disorders in cattle. Noteworthy accomplishments in bloat research chronicled in JAS include the nature of ruminal contents in legume and feedlot bloat, the role of plant fractions and microbial populations in the development of bloat, and the efficacy of poloxalene, ionophores, and, more recently, condensed tannins in decreasing the incidence and severity of bloat. Although less research has been published on PEM in JAS, early publications highlighting the association between PEM and ruminal acidity and the role of thiaminase in certain forms of the disorder, as well as more recent publications related to the role of sulfur in the development of PEM, are noteworthy contributions. Since the 1940s, outstanding and often-cited review articles have made JAS a highly visible source of information on these disorders. Thus, JAS has played a significant role as a repository for information pertaining to metabolic and digestive disorders in cattle and other ruminants, and it will no doubt continue to be a premier resource for information on these conditions during the second century of the American Society of Animal Science. [ABSTRACT FROM AUTHOR]

American Society of Animal Science members, publishing in Journal of Animal Science (JAS), completed research that resulted in understanding the estrous cycle of cattle, which led to the ability to inseminate cattle on a given day with pregnancy rates similar to those achieved by 21-d breeding by a fertile and sound bull. Research published in JAS led to understanding estrus, ovulation, the estrous cycle, and postpartum interval for cattle (1930s through 1960s) and hormonal factors affecting corpus luteurn lifespan of cattle (1950s through 1980s). Research during the 1940s to 1960s, using gonadotropins and progesterone to manage the estrous cycle of cattle, established the concepts for estrous synchronization and stimulated commercial research directed at developing cost-effective progestogen estrous synchronization products, leading to commercially available products from 1967 through today (Repromix, melengestrol acetate, Syncro-Mate-B, controlled internal drug release). Prostaglandin F2α products were approved for estrous synchronization (1970s, 1980s), and GnRH products were approved for use in cattle to treat ovarian follicular cysts (1970s, 1980s). Research published in JAS was essential for understanding the biology of and potential value of both PGF2α and GnRH and contributed both to new knowledge and scientific bases for future Food and Drug Administration Center for Veterinary Medicine approval of those products. Research during the 1980s through 2000s led to understanding ovarian follicular waves and described the timing of follicular recruitment, selection, dominance, arid atresia; this research was essential for the ability to effectively manage follicles to achieve success with timed AT. The knowledge gained through research published in JAS resulted in development of the numerous estrous synchronization and breeding management protocols that are cost- effective and meet the breeding management needs of most beef and dairy enterprises. [ABSTRACT FROM AUTHOR]

Discoveries, understanding, and innovations in meat science during the last century have led to revolutionary changes in meat and poultry production, processing, marketing, and consumption. American Society of Animal Science members have made key contributions in most, if not all, categories of advancement. The first US university meat science program was begun in Minnesota in 1905. Use of mechanical refrigeration in the meatpacking industry, improved transportation and packaging, and home refrigeration provided more flexibility, variety, and consistency in meat and meat products in the early 1900s. Cooperative meat research was begun by 27 universities in 1925, with a focus on the observational characterization of carcass traits and composition, meat quality attributes, and causes of the wide variation in these variables. Scientific study of genetic, nutritional, and environmental influences on the growth, physiology, and postmortem biochemistry of muscle often used muscle-comparative investigations. Rigor mortis, cold shortening and thaw rigor, postmortem muscle metabolism, postmortem tenderization and tenderness variation, and postmortem myoglobin and lipid oxidation were studied vigorously in the 1960s and beyond, defining the biochemical bases for associated outcomes in fresh and processed products. Value-added benefits resulted from implementation of electrical stimulation, boxed beef and modified-atmosphere packaging, restructuring technologies, collagen recovery, and muscle profiling work. Isolation, purification, and definition of the primary structure and biophysical properties of the myofribillar and cytoskeletal proteins in muscle aided the understanding of contraction and postmortem changes. The role of Ca-dependent proteases in meat tenderness and muscle growth is being clarified. The chemistry of meat curing, meat emulsion formation, fermentation, and other processing methods led to new technologies, new meat products, and new benchmarks in product shelf life and quality. Meat safety assurance and our ability to manage the microbiological causes of food-borne illness and spoilage are imminently important now and in the future. [ABSTRACT FROM AUTHOR]

The last century of food animal agriculture is a remarkable triumph of scientific research. Knowledge derived through research has resulted in the development and use of new technologies that have increased the efficiency of food production and created a huge animal production and food manufacturing industry capable of feeding the US population while also providing significant quantities of high-quality food for export to other countries. Although the US food supply is among the safest in the world, the US Center for Disease Prevention and Control estimates that 76 million people get sick, more than 300,000 are hospitalized, and 5,000 die each year from foodborne illness. Consequently, preventing foodborne illness and death remains a major public health concern. Challenges to providing a safe, abundant, and nutritious food supply are complex because all aspects of food production, from farm to fork, must be considered. Given the national and international demand and expectations for food safety as well as the formidable challenges of producing and maintaining a safe food supply, food safety research and educational programs have taken on a new urgency. Remarkable progress has been made during the last century. Wisdom from a century of animal agriculture research now includes the realization that on-farm pathogens are intricately associated with animal health and well-being, the production of highquality food, and profitability. In this review, some of the developments that have occurred over the last few decades are summarized, including types, sources, and concentrations of disease-causing pathogens encountered in food-producing animal environments and their association with food safety; current and future methods to control or reduce foodhorne pathogens on the farm; and present and future preharvest food safety research directions. Future scientific breakthroughs will no doubt have a profound impact on animal agriculture and the production of high-quality food, but we will also be faced with moral, ethical, and societal dilemmas that must be reconciled. A strong, science-based approach that addresses all the complex issues involved in continuing to improve food safety and public health is necessary to prevent foodborne illnesses. Not only must research be conducted to solve complex food safety, issues, but results of that research must also be communicated effectively to producers and consumers. [ABSTRACT FROM AUTHOR]

Over the next quarter century in North America, the following eventualities are likely for physiology and endocrinology research with agricultural animals. 1) Total funding adjusted for inflation will change little but will come less from public sources, and most of that will be in the context of human health. Much of the privately funded research will be herd specific and remain proprietary. 2) The numbers of MS, PhD, and postdoctoral students probably will decrease, but research in the context of credentialing will remain important. 3) Resources such as expanded databases in genomics and proteomics, and remarkable new tools such as small inhibitory RNA will continue to become available, likely at a faster rate than in the previous 25 yr. 4) The huge amounts of data from production agriculture will make agricultural animals ideal models for some kinds of basic research, such as studying fetal programming, resulting in synergy with more applied research. Most of these experimental animals will be in private production herds and flocks, even when work is publicly funded. 5) The trend toward more interdisciplinary research will continue, especially considering interactions among reproduction, health, nutrition, selective breeding, management factors, and societal concerns; reductionist research probing deeper into cellular and molecular mechanisms will remain important, as will whole-animal approaches. 6) Agricultural animals are a product of evolution plus selective breeding. Insights drawn from the former will aid progress in the latter. One focus of research in physiology and endocrinology will be understanding heterosis, inbreeding depression, and epigenetic effects as it becomes possible to manipulate and identify the allelic structure of individual animals. 7) Additional insightful concepts will evolve that will simplify thinking in some respects, such as the maternal to embryonic shift in transcribed RNA in early embryos; however, animal biology will turn out to be even more complex than most of us currently imagine. [ABSTRACT FROM AUTHOR]

Pastures, forages, and grasslands dominate the landscape across the United States and sup- port a large ruminant population that supplies the nation with value-added animal products. A historical perspective is presented of the innovations as they occurred in the Journal of Animal Science over the past 100 yr in pasture and forage research. Consideration was given to both animal and pasture perspectives. Areas given consideration from the animal perspective were schemes for feedstuff analysis, experimental design and statistics, forage sample preservation, indirect methods of measuring intake and digestion, TDN and energy, nutritive value, harvested forage, and innovations in the grazing environment. Areas given consideration from the forage perspective were a framework for forage-animal interface research, determining pasture yield, choice of stocking method, grazing management, partitioning of forage DM, near-infrared reflectance spectroscopy technology, antiquality constituents, and forage sample preservation. Finally, the importance was discussed of applying research results from the forage- animal interface to general ruminant nutrition research beyond the interface that is focused on altered diets. [ABSTRACT FROM AUTHOR]

One hundred years ago, there were more than 48 million sheep in the United States. In 1910, they were valued at $4/head, with 43% of income coming from the sale of sheep, lambs, and meat and 57% coming from wool. Over the years, fluctuations in this ratio have challenged the breeder and researcher alike. By 2007, sheep numbers had declined to 6.2 million, with the average sheep shearing 3.4 kg of wool (representing <10% of income), 0.2 kg more than in 1909 but 0.5 kg less than fleeces in 1955. Sheep operations have declined by more than 170,000 in the past 40 yr. A cursory examination of this information might lead one to conclude that animal science research has made little impact on sheep production in the United States. On the contrary, lamb crops in the new millennium (range = 109 to 115%) are greater than those recorded in the 1920s (85 to 89%) and dressed lamb weights increased from 18 to 32 kg from 1940 to the present. In the past century, researchers conducted thousands of investigations, with progress reported in new, existing, and crossbreed evaluations, quantitative and molecular genetics, selection, nutrition, fiber, meat, hides, milk, growth, physiology, reproduction, endocrinology, management, behavior, the environment, disease, pharmacology, toxicology, and range, pasture, and forage utilization such that a vast amount of new information was accrued. Our understanding of sheep has benefited also from research conducted on other species, and vice versa. Many factors that have contributed to the decline in the sheep industry are not influenced easily by academic research (e.g., low per capita consumption of lamb meat, predation, reluctance to adopt new technologies, cost and availability of laborers with sheep- related skills, and fewer young people pursuing careers in agriculture). The size of the US sheep industry is expected to remain stable, with possible slow growth in the foreseeable future. To remain profitable, producers will take advantage of new (or previously unused) technologies, the desire of the public for things natural, domestic niche and international fiber markets, and the ability of the sheep to control noxious weeds and thrive in suboptimal ecosystems. [ABSTRACT FROM AUTHOR]

We are a nation of dog lovers. Never before in our history have we spent more time, money, and emotional energy on a group of animals that are kept solely for companionship. Pet food sales are a multi-billion dollar industry, and pet owners are spending more than 11 billion dollars each year on veterinary care. This devotion is further illustrated by the exponential growth of the pet supply industry, including increasing numbers of pet superstores, play-parks, training centers, and doggie day care centers. During the 1980s, recognition of the human-animal bond led to serious study of the roles that dogs play in our lives. These studies have shown that pets provide significant benefits to our emotional, physical, and social well being. It is ironic then, that at a time when we recognize and appreciate our bonds with animal companions, dark elements of this relationship are equally pervasive. Animal shelters in the United States kill between 3 and 4 million dogs and cats annually. Dog fighting, although outlawed, has reached epidemic proportions in some areas of the country. Episodes of animal cruelty and neglect are reported with alarming frequency in the media; so frequently that discussions of the connection between animal cruelty and human violence have become daily parlance. How then did we come to have such paradoxical perceptions and treatment of our canine companions? This question is explored through an examination of the ancestry of the dog and the prevailing myths and facts about domestication. Historical and present-day perceptions of the wolf and the impact that these attitudes may have upon perceptions of dogs are examined. [ABSTRACT FROM AUTHOR]

Development of nutritional energetics can be traced to the 1400s. Lavoisier established relationships among O2 use, CO2 production and heat production in the late 1700s, and the laws of thermodynamics and law of Hess were discovered during the 1840s. Those discoveries established the fundamental bases for nutritional energetics and enabled the fundamental entity ME = retained energy + heat energy to be established. Objectives became: 1) to establish relationships between gas exchange and heat energy, 2) to devise bases for evaluation of foods that could be related to energy expenditures, and 3) to establish causes of energy expenditures. From these endeavors, the basic concepts of energy partitioning by animals were developed, ultimately resulting in the development of feeding systems based on NE concepts. The California Net Energy System, developed for finishing beef cattle, was the first to be based on retained energy as determined by comparative slaughter and the first to use 2 NE values (NEm and NEg) to describe feed and animal requirements. The system has been broadened conceptually to encompass life cycle energy requirements of beef cattle and modified by the inclusion of numerous adjustments to address factors known to affect energy requirements and value of feed to meet those needs. The current NE system remains useful but is empirical and static in nature and thus fails to capture the dynamics of energy utilization by diverse animals as they respond to changing environmental conditions. Consequently, efforts were initiated to develop dynamic simulation models that captured the underlying biology and thus were sensitive to variable genetic and environmental conditions. Development of a series of models has been described to show examples of the conceptual evolution of dynamic, mechanistic models and their applications. Generally with each new system, advances in prediction accuracy came about by adding new terms to conceptually validated models. However, complexity of input requirements often limits general use of these larger models. Expert systems may be utilized to provide many of the additional inputs needed for application of the more complex models. Additional information available from these systems is expected to result in an ever-increasing range of application. These systems are expected to have increased generality and the capability to be integrated with other models to allow economic evaluation. This will eventually allow users to compute solutions that allow development of optimal production strategies. [ABSTRACT FROM AUTHOR]

Proteomics holds significant promise as a method for advancing animal science research. The use of this technology in animal science is still in its infancy. The ability of proteomics to simultaneously identify and quantify potentially thousands of proteins is unparalleled. In this review, we will discuss basic principles of doing a proteomic experiment. In addition, challenges and limitations of proteomics will be considered, stressing those that are unique to animal sciences. The current proteomic research in animal sciences will be discussed, and the potential uses for this technology will be highlighted. [ABSTRACT FROM AUTHOR]