bluuebunny/crossref_metadata_2025_split huggingface dataset:
39 Management of cereal-grain forages for yield and quality
Authors: Coblentz Wayne K , Akins Matthew 
Published: July 2019

Abstract
Cereal-grains have a long history of providing quality forage for livestock operations. Our objective is to review the existing literature and describe the principle factors controlling the yield and quality of cereal-grain forages. Generally, cereal-grain forage production can occur via management scenarios that include: 1) winter-annuals planted during fall and then grazed or harvested the following spring; 2) cereals not requiring vernalization planted during early spring and harvested during late-spring or summer; and 3) cereals not requiring vernalization planted during late-summer and harvested before winter. Winter-annuals planted during fall also are used extensively for fall grazing, particularly for backgrounding stocker cattle. The requirement for vernalization before plants elongate and produce viable seed plays a large role in synchronizing management strategies with producer goals. For example, maximization of fall growth can be attained by choosing a species or cultivar that does not require vernalization and will elongate, but this choice will likely eliminate winter survival and subsequent spring forage production. Ambient temperature during plant maturation affects lignin formation positively; therefore, forages grown during cooler fall temperatures will typically exhibit greater NDF digestibility than those maturing during summer. Most nutritional characteristics are influenced heavily by two competing processes that include the normal negative maturation effects that reduce the quality of most forages. However, this process is juxtaposed against the physiological process of grain fill, which can dilute concentrations of forage fiber components, increase energy density, and improve DM digestibility at advanced plant-growth stages. Digestibility of NDF declines with plant maturity, and generally is not affected by grain fill. A boot-stage harvest for silage often exhibits the most favorable nutritional characteristics for lactating dairy cows; however, producers making this management choice will need to accept a substantial yield penalty compared with a commonly recommended harvest at soft-dough stage, which would likely maximize yield.
41 Management effects on long-term crop yield stability in central and eastern nebraska
Authors: Jin Virginia , Sindelar Aaron , Schmer Marty , Wienhold Brian 
Published: July 2019

Abstract
The sustainability and resilience of cropping systems will depend on how different management practices impact yield stability over the long-term. Here, we summarize the effects of crop rotation, tillage, crop residue removal, and nitrogen fertilizer rate on corn and soybean yield responses from several long-term research experiments maintained by the USDA-Agricultural Research Service in eastern and central Nebraska. Across all study sites, we found that yield stability is affected most by crop rotation, then tillage, then residue management, where stability can be further improved in all systems by using the optimum N fertilizer rate. While crop rotation and rotation complexity tend to have the greatest impact on long-term yield stability in the western Corn Belt, nearly all combinations of management can produce stable yields if well managed.
46 How far we could go reducing crude protein with the use of supplemental amino acids
Authors: Pomar Candido 
Published: July 2019

Abstract
Feeding growing pigs with diets providing the required amount of essential and non-essential amino acids (AA) reduces energy expenditure and minimizes N excretion. Low protein diets can be obtained by supplementing feeds with crystalline AA. Numerous experiments have evaluated the ideal dietary AA concentration at different growth stages, but reducing dietary protein with the use of supplemental AA is limited by the inaccuracy of the principles used to estimate AA requirements. One of these principles states that growing animals need AA for maintenance and growth. Maintenance requirements are related to BW whereas the efficiency of AA utilization (e.g., 72% for Lys) and body protein AA composition are constant (e.g., 7% for Lys). These parameters are, however, affected by AA restriction, meal frequency, energy supply, genetics, etc. Even when controlling these factors, individual pigs respond differently to the same AA supply. Yet pigs are raised in groups and fed with a unique feed for long periods. Individual pigs within a given population differ in terms of BW, ADG, health status, etc., and consequently, differ in the amount of AA they need at a given time. Therefore, when feeding a group of pigs, the concept of maintenance and growth requirements may not be appropriate. In this situation, nutrient requirements should be seen as the optimal balance between the proportion of animals that needs to be overfed and underfed. Given that for most AA, underfed animals exhibit reduced performance, whereas overfed animals exhibit near-optimal performance, optimal growth is obtained when nutrients are provided to satisfy the requirements of the most demanding animals. There is therefore a trade-off between performance and dietary protein reduction. The inaccuracy of the principles used to estimate AA requirements, both for individual animals and populations, limits how far we can go reducing dietary protein with the use of supplemental AA.
43 Commercial realities of amino acid nutrition in the young pig
Authors: Cook David A , Pilcher Chad , Humphrey Brooke 
Published: July 2019

Abstract
Applied amino acid nutrition continues to provide new and meaningful solutions to support advancements in animal performance, health and sustainability. While there continues to be focus on how amino acid nutrition can be optimized for performance, there remains to be opportunity to optimize applied nutrition for the young pig in order to support the weaning transition. As alternatives for antibiotics and heavy metals continue to be explored, their success will in large part depend upon the successful application of amino acid nutrition. There are several complicating factors related to applying amino acid nutrition in the young pig. First, intestinal function at weaning is compromised, resulting in reduced digestive and absorptive capacity. From an amino acid nutrition standpoint, this can lead to increased N flow into the hindgut where it can be fermented into inflammatory irritants, resulting in diarrhea and poor growth. Second, ideal protein models for digestive health are scarce and often approaches of limiting lysine inclusion as a percent of crude protein are used as an alternative. Third, the application of amino acid nutrition is based upon digestibility values obtained from older animals. Review of the literature indicates that these are in excess of what the young pig can digest, further impacting the N flow to the ileum and hindgut. As we continue to apply amino acid nutrition at the commercial level, we must look for solutions to address these items while more basic work can be done to obtain the needed information on digestibility and requirements.
50 Role of fatty acid nutrition in milk fat synthesis
Authors: Lock Adam L 
Published: July 2019

Abstract
Our understanding of fatty acid (FA) digestion and metabolism in dairy cows has advanced significantly in the last few decades. We now recognize that FA, both of dietary and rumen origin, can have different and specific effects on feed intake, rumen metabolism, small intestine digestibility, milk fat synthesis in the mammary gland, and energy partitioning between the mammary gland and other tissues. We will present research focusing on specific FA and how dairy cows respond differently to combinations of FA. Recent research has highlighted differences in intestinal digestibility among palmitic acid (C16:0), stearic acid (C18:0), and oleic (cis-9 C18:1) acids, which impacts the amount and profile of absorbed FA available for metabolic purposes including milk fat synthesis. C16:0, C18:0, and cis-9 C18:1 usually comprise the majority of FA present in milk fat and adipose tissue of dairy cows. In addition, these FA comprise the major FA in a wide range of commercially available fat supplements. While these FA have different functions in metabolism, they may also interact with each other by competitive or complementary mechanisms under different physiological conditions. In the mammary gland, milk FA are derived from 2 sources; 16 carbon FA originating from extraction from plasma. 16-carbon FA originate from either de novo or preformed sources. Milk lipid synthesis in the mammary gland is dependent upon the simultaneous supply of short/medium-chain FA and long-chain FA. C16:0 has a higher preference as a substrate to start triglyceride synthesis than C18:0 or cis-9 C18:1. Also, if the amount of preformed FA surpasses the capacity of the mammary gland, these might be redirected to other tissues (e.g. adipose tissue) altering energy partitioning. In the future, the opportunity and challenge will be to continue to improve our understanding of how and which FA affect nutrient digestion, energy partitioning, and milk synthesis in lactating dairy cows and effectively apply this knowledge in the feeding and management of high producing dairy cows.
51 Feedstuff fatty acid content, variation, techniques and implications on practical animal nutrition
Authors: Ocker Cliff 
Published: July 2019

Abstract
Fatty acid nutrition in ruminants, dairy cattle primarily, has increased as a point of emphasis with nutrition formulation in the past decade, as the diet fatty acid profile and metabolism has been found to impact milk fat concentration and animal health. Both the fatty acid supply and rumen degradation warrant further investigation in dairy diets for improved formulation strategies in the future. As supply and degradation are better understood, improved formulation approaches will be possible now that routine feed fatty acid measures have become more practical with the development of near-infrared reflectance spectroscopy (NIR) models at commercial feed analysis laboratories. NIR model development techniques vary; however, the general approach is to calibrate against a wide ranging database of feedstuff wet chemistry measures using a partial least squares approach. Models relate spectral observations (i.e. reflectance at a specific near-infrared light wavelength) to wet chemistry observations. NIR models should reflect both the mean and variation observed in the wet chemistry database. The NIR models developed by Rock River Laboratory, and resulting feed library database information presented in Table 1, were developed by calibrating against feedstuff chemistry performed at the Lock laboratory with Michigan State University. Wet chemistry fatty acid determination by analytical laboratories, using gas chromatography techniques against known fatty acid standards, deserves further discussion to agree upon peak identification schemes. Differences in peak identification from one laboratory to the another will result in different total fatty acid measures and NIR models. The fatty acid content and profile coefficients of variation, determined from the mean and standard deviations presented in Table 1, range from less than 10 to over 100% of the mean with an average CV of 27%. This suggests substantial variation is present in commercial feeds, and opportunities may exist to better account for variation and fatty acid supply in dairy diets.
53 Young Scholar Presentation: Diet starch concentration and starch fermentability affect energy intake and production of dairy cows during the postpartum period
Authors: Albornoz Rodrigo I , Allen Michael 
Published: July 2019

Abstract
Our objective was to evaluate the effects of starch concentration and starch fermentability of diets fed during the early postpartum (PP) period on DM and energy intake and production. Fifty-two multiparous Holstein cows were used in a completely randomized block design with a 2 X 2 factorial arrangement of treatments. Treatment diets were formulated to 22% (LS) or 28% (HS) starch with dry-ground corn (DGC) or high-moisture corn (HMC) as starch source. Treatments were fed from 1 to 23 d PP, and cows were switched to a common diet until 72 d PP to measure carryover (CO) effects. Throughout the experiment, DMI and MY were measured daily, and milk components and BW were measured weekly. During the TP, feeds, refusals, and fecal samples were collected and digestibility was determined weekly. During the TP, HMC decreased intakes of DM and net energy of lactation (NEL) more when included in the HS (3.9 kg/d and 3.2 Mcal/d) than in the LS (0.9 kg/d and 0.6 Mcal/d) diets and HMC decreased yields of milk, fat, protein, 3.5% FCM and milk NEL by 4.3, 0.19, 0.18, 4.8 kg/d and 2.8 Mcal/d, respectively. Energy balance was improved by HS compared with LS (-14.7 vs. -16.8 Mcal/d). During the CO period, treatment effects on DMI diminished over time with no main effects of treatment for the entire period. Treatments interacted to affect yields of milk, milk fat and FCM during the CO period, which were greater for HS-DGC and LS-HMC (54.8 and 52.8, 1.76 and 1.81, and 51.3 and 52.2 kg/d, respectively) than for LS-DGC and HS-HMC (51.2 and 51.0, 1.68 and 1.64, and 48.4 and 48.6 kg/d, respectively). Feeding a highly fermentable starch source during the early PP period decreased DM and energy intake and production, with treatment effects diminishing during the CO period.
Nutrition as a way to improve the dairy industry sustainability: a nutrigenomic approach
Authors: Riboni Mario Vailati , Roche John , Yoon Ilkyu , Loor Juan 
Published: July 2019

Abstract
Due to the high incidence of diseases and high culling rate, the peripartum is a period of significant stress, and its management sets the stage for the health, future productivity and reproductive performance of the herd, hence making it the perfect target to improve the industry sustainability as a whole. Looking at grazing systems, using a nutrigenomic approach, we determined that, contrary to historic industry standards, cows should be slightly underfed (~75% of their energy requirements) in the three weeks before parturition to prime their metabolism and ensure an optimal transition. Farmer will be able to preserve pasture area in a period of low forage production, reaching the spring (calving season) with abundant and high quality pasture. While looking at confined systems we tested the supplementation efficacy of immunomodulatory nutrients. The greater feed intake and greater milk production performances (both in milk quantity, and quality), coupled with lower incidence of disease, underscore a smoother transition to lactation when cows are supplemented with rumen-protected methionine. Moreover, methionine induced greater blood neutrophil phagocytosis and oxidative burst postpartum, and optimized the response to LPS, by mitigating the hyper-response of the immune cells. Supplementation of cows undergoing a mastitic challenge with a S. cerevisiae fermentation product improved indexes of mammary gland health and pathogen resistance. Pathway analysis highlighted physiological mechanisms enhancing local immune cell trafficking, antimicrobial activity, and inflammation control in the mammary gland of supplemented animals, compared to control cows that showed signs of tissue damage and loss of epithelial integrity. Looking at calf nutrition, enhancing nutrient intake in the pre-weaning period stimulates mammary development, increasing their future productivity potential. Nutritional improvement of animal health shows great potential as a rapidly applicable strategy to improve animal welfare, allowing them to express their full genetic potential.
57 Impact of weaning stress, disease, and diet on pig performance, intestinal function and integrity
Authors: Gabler Nicholas K , Helm Emma T , Mille Carson De 
Published: July 2019

Abstract
Inevitably, pigs will experience stressors that antagonize lean tissue accretion, appetite, and feed conversion. Depending on the production system and age of the pig, these stressors commonly include weaning transition, diet changes, vaccination, enteric and respiratory pathogen challenges, activation of the HPA axis, and social stress. Additionally, the morbidity and mortality that accompany these stressors may be exacerbated by the illegalization of sub-therapeutic antibiotic use for growth promotion (AGPs) by the Veterinary Feed Directive. However, morbidity and mortality may also be mitigated by diet ingredients via direct and indirect modes of action on gastrointestinal health and function. The gastrointestinal tract has the vital but conflicting functions of nutrient and water absorption, while simultaneously regulating host mucosal defenses against noxious luminal contents such as microorganisms and their toxins. This puts the gastrointestinal tract epithelium and splenic tissue at the front line of nutrition, growth, and health of the pig in the new age of antimicrobial resistance concerns. As part of the body’s splanchnic tissues, the gastrointestinal tract is very metabolically active and has high utilization of luminal nutrients and energy. This utilization or “first pass metabolism” by intestinal epithelial and lamina propria cells can be a major determinant of the systemic or post-absorptive availability of glucose, essential and non-essential amino acids, and short and long chain fatty acids. This makes the gastrointestinal tract critically important to the growth and health of livestock and avian species. This paper will discuss the physiological impact of various stress challenges and nutrition on pig performance, gastrointestinal function and integrity.
62 Improved estimation of indirect social genetic effects in group-housed pigs by quantifying behavioral interactions
Authors: Barajas Belcy Karine Angarita , Cantet Rodolfo , Wurtz Kaitlin E , O’Malley Carly , Siegford Janice , Ernst Catherine , Steibel Juan P 
Published: July 2019

Abstract
Traditional social genetic effects modeling assumes uniform intensity of interaction between group members. Tree breeders proposed relaxing this assumption by incorporating estimates of intensity of competition between pairs of individuals. Here, we incorporated the quantification of aggressive interactions between pairs of animals in the estimation of indirect social genetic effects on skin lesions in the anterior part of the body in growing pigs. The data consisted of 491 pigs (215 barrows and 276 gilts, mean of 66 ±5 days of age). Animals were housed in 37 pens (11 to 15 pigs by pen) over 7 replicates. Trained scorers counted the number of skin lesions immediately before and 24 hours after mixing pigs. Animals were video-recorded for 9 hours post mixing and trained observers quantified the type and duration of aggressive interactions between pairs of pigs. The number of skin lesions in the frontal part of the body 24 hours post-mixing was the response variable and the number of seconds that pairs of animals spent engaged in reciprocal fights was used to quantify the intensity of interaction. We compared three different models: A direct genetic additive model (DGE), a traditional social genetic effect model (TSGE) assuming uniform interactions, and an improved social genetic effect model (ISGE) that used intensity of interaction to parameterize social genetic effects. All models included fixed effects of sex, replicate, lesion scorer, initial weight and pre-mixing lesion count; a random effect of pen; and a random direct genetic effect. The model ISGE recovered the most variance (smallest σe2) and resulted in the highest estimated h2 (P < 0.005). The model TSGE produced estimates that did not differ significantly from DGE (P = 1). Contrarily, incorporating the intensity of interaction into the modeling of ISGE allowed direct and indirect genetic effects to be estimated separately, even in a small dataset.
66 A genome-wide association study for gestation length in swine
Authors: See Garrett , Trenhaile-Gannemann Melanie , Ciobanu Daniel , Spangler Matthew L , Mote Benny 
Published: July 2019

Abstract
The objective of the current study was to conduct a genome-wide association on gestation length (GL) in different parities in swine. Sows (n = 831) belonging to the University of Nebraska – Lincoln resource population (Landrace X Nebraska Index Line) were utilized. GL was defined as the number of days between the final insemination and farrowing. Four traits, GL at parity 1, 2, 3 and 4 (GL1, GL2, GL3 and GL4, respectively) were investigated. Animals which were induced 24h prior to a farrowing event were removed from the analysis. Sows were genotyped with the Illumina SNP60 BeadArray. A Bayes C model with π=0.995 was implemented with fixed effects of contemporary group, development pen, diet, linear and quadratic terms for age at puberty (GL1; P < 0.01), and linear and quadratic terms for farrowing age (GL2; P < 0.01). Results are posterior means of 55,000 samples.Single marker association analysis (SMA) was performed in R utilizing a linear model on SNP from 1-Mb windows (n = 10) which explained the largest proportion of genetic variation in GL1. Top 10 (0.5% of all windows) 1-Mb windows accounted for a limited proportion of genetic variance, 7.75, 4.66, 3.45 and 2.05% in GL1, GL2, GL3 and GL4, respectively. Posterior mean heritability estimates (posterior SD) for GL1, GL2, GL3 and GL4 were 0.33 (0.06), 0.34 (0.07), 0.32 (0.08) and 0.20 (0.08), respectively. The top SNP (ASGA0017859, SSC4, 7.8 Mb) located in one of the two top common genomic regions associated with GL1, GL2 and GL3 displayed a difference of 1.1d in GL1 between alternate homozygotes (P < 0.01). The top SNP from nine of the ten regions were significant (P < 0.05) in the SMA. Two of these regions were in common with GL2 and GL3 where SNP with potential functional effects were found in ZFAT, MAML2 and CCDC82. Results suggest GL is a largely polygenic trait.