bluuebunny/crossref_metadata_2025 huggingface dataset:
308 Awardee Talk: Prevention and mitigation of pathogens in feed and feed manufacturing systems
Authors: Harrison Olivia , Woodworth Jason C , Paulk Chad B , Gebhardt Jordan T , Jones Cassandra K
Published: May 2024

Prior to 2013, pathogen transmission through feed was focused primarily on bacteria and biosecurity was used to prevent adulterant entry into the ingredients and the feed mills. Following the porcine epidemic diarrhea virus (PEDV) outbreak in 2013, research focused on pathogen mitigation and control quickly became a subject of interest. Since PEDV, multiple endemic viruses and foreign animal diseases have been found to be transmissible in feed or feed ingredients. As African swine fever virus (ASFV) spread closer to the United States and endemic pathogens are a continued pressure on production systems, it is imperative that prevention measures are included in the feed supply chain and options for mitigation are fully elucidated for times of need. Previous research has demonstrated that preventative measures such as boot baths, lines of separation, showers, and changing clothes are effective measures when appropriately maintained. However, these protocols can seem costly and burdensome to employees, especially when the risk of disease transmission appears low. Employee training is difficult as disease transmission is difficult to visualize and exhibit the importance of each measure. Glo Germ, a florescent substance, is a cost-effective training tool which can demonstrate the efficacy of prevention protocols and can identify areas where biosecurity measures have not been properly utilized. Preventative measures are the first line of defense for feed manufacturing systems, but understanding and using mitigation techniques in the event of contamination can limit pathogen spread and protect the rest of the feed supply chain. Pelleting, as a method of thermal inactivation process, has recently been demonstrated to lessen the quantity of detectable viral RNA and decrease the risk of infection. The pelleting process, however, is a point-in-time mitigant and does not decrease the risk of product re-contamination as feed continues down the supply chain. The use of chemical mitigants, like formaldehyde, medium-chain fatty acids, and organic acids, can decrease the presence of bacterial and viral pathogens with longer-lasting mitigation properties. These mitigants can either be used in the feed itself, or as an addition to flushing batches which help disperse the chemical mitigants throughout the feed manufacturing equipment, thus reducing the risk of product re-contamination. In the event more drastic measures must be taken to eliminate pathogen presence from feed mills, gaseous fumigation and the use of portable heaters show promise as methods to decontaminate feed manufacturing equipment without the use of water or complete equipment breakdown. Overall, effective training and implementation of preventative measures are needed to provide pathogen-free feed to production systems, but continued research in mitigation and mill decontamination will further protect the feed supply chain in the event of pathogen contamination.
42 Group sow housing considerations for improved survival and productivity
Authors: Campbell Roger
Published: May 2024

Group sow housing considerations for improved survival and productivity. The Australian pork industry decided in 2010 to voluntarily phase out stall housing for pregnant sows by 2017. The change was supported by extensive R&D by the Pork CRC for High Integrity Australian Pork and the time line was brought forward by two major retailers in Australia. For 85 to 90% of producers the transition was complete by 2019-2020 and sows were grouped at weaning or straight after mating. I reviewed the pertinent literature, interviewed many producers on what is required to make group housing successful for the sow and the producer and looked at trend from an Australian bench making project in some aspects of reproduction and sow mortality from 2006 to 2020. The research showed sows adapt to grouping and exhibit reduced aggressive behaviors, injuries and plasma indicators of stress within 4 to 5 d after mixing. During this period, it was all about space at mixing, grouping sows based on size/parity, ensuring they all receive adequate feed and familiarization with group housing by the sow and staff. Producers said it is all about ensuring sows are grouped on size/parity, feeding with many using ad libitum feeding for the week after mixing, space with a preference between 1.8 and 2.2 m2, flooring (slats preferred) and minimizing mixing events. Producers were split on the use of drop feeding and electronic sow feeders with opinions very divided. For drop feeding the preferred housing system comprised full length feeding stalls without a back gate. All producers said they would not go back to stalls. Most producers experienced a decline in farrowing rate and increased lameness during the transition. However, reproduction improved over time and sow mortality decreased. If the top 4 to 5 factors affecting aggressiveness and overall welfare are followed, group housing sows improves their welfare and does not reduce their reproductive performance or longevity. Detection of estrus can be more difficult in groups and a number of Australian producers have implemented the use of satiety blocks during the first 2 and last 2 wk of gestation to further improve welfare and meet retailer requirements. Mating in groups (not stalls) has also been reported to improve reproduction.
38 Pig survival: Current state of the US swine industry
Authors: Flohr Josh , Williams Noel H , Williams Hadley
Published: May 2024

Pig survivability stands as a formidable challenge for the United States Swine Industry, constituting both the foremost economic hurdle and a prominent sustainability concern. The economic dimension of this challenge has been accentuated by escalating production costs driven by the surge in feed inputs, labor expenses, and other variable cost increments. Current estimations of birth-to-market survivability, ranging from 60% to 85%, underscore the urgency of addressing this multifaceted issue, with sow livability varying from 70% to 90%, contingent upon the data source and housing system (e.g., Prop-12, Open Pen Gestation; Ross et al., 2019). This presentation delves into the intricate web of factors contributing to the decline in survivability, encompassing genetic influences, heightened disease pressures, biosecurity concerns linked to pig density, evolving management practices, and the aging infrastructure of facilities. While extensive research has been dedicated to each of these facets, advancements in swine survivability remain constrained, with some indicators suggesting a troubling increase in challenges. The presentation seeks to offer a comprehensive review of the current state of swine industry survivability, elucidating the persistent challenges and, crucially, identifying untapped areas of opportunity. By navigating through the complex landscape of economic constraints, environmental considerations, and technological interventions, the symposium aims to provide insights that can guide the industry towards innovative solutions, fostering a more resilient and sustainable future for the United States Swine Industry.
39 Using genetics and technology to improve swine robustness
Authors: Hamilton Dan N , Culbertson Miranda , Holl Justin W
Published: May 2024

Abstract Pig robustness has been an increasing concern in the global swine industry over the last 10 yr. This trend of increased mortality across all phases of production continues to worsen over time despite greater focus on research, management, and other production practices to control it. During this time, dramatic improvements in genetic progress have been realized through the selection of economically important traits. Historically, swine genetic companies have relied on data from their purebred animals reared in high-health and well-managed environments which has proven difficult to provide meaningful insight on variation in robustness traits. More recently, leading genetic companies have invested in large commercial test herds where crossbred pigs and breeding animals are individually identified with pedigree and genomic information. These pigs are reared under challenging and varying commercial conditions and mortality, removals, and reproductive efficiency data are gathered and used to generate crossbred breeding values. This type of data increases the accuracy of genetic estimates as well as creates new traits aimed at improving robustness and ease of management. Further investments have been made in precision livestock farming technologies such as computer vision which is quickly being developed due to the low cost of cameras and the ability to use edge computing to process images in real-time or to transfer images and data to the cloud. These developments are particularly compelling in the genetic improvement space when they can be paired with individual animal identification enabling novel traits to be measured in large populations more consistently and at a reduced cost compared with previous labor-intensive or cost-prohibitive methods. Early examples of this are the use of cameras to score feet and leg soundness in replacement gilts as lameness and associated feet and leg injuries are still one of the largest contributors to sow culls and mortality. This new digital feet and leg soundness scoring method has initially resulted in dramatically greater accuracy and heritability compared with conventional subjective human scoring methods. Other camera-based algorithms have been developed to track individual pigs and assess their daily behaviors and interactions. These developments are key to collecting new phenotypes for the selection of positive behavior traits for genetic selection compared with what was previously possible with human observer or scan sampling methods. Gene editing is another promising technology that has been used in human health and plant breeding but is now being widely researched in livestock. This technology has been used to create the first PRRS-resistant pigs to address one of the most costly diseases in the industry. New sources of data and technologies are key to creating and capturing existing and novel phenotypes on large populations of pigs in commercial environments to aid in the genetic improvement of non-conventional traits.
223 Survey of veterinarians who use pentobarbital for euthanasia suggests knowledge gaps regarding animal disposal
Authors: Murphy Mike , Cornwell Emily
Published: May 2024

To assess 1) knowledge and practices of veterinarians regarding disposal of euthanized animals, 2) the extent to which veterinarians communicate with their clients about potential risks of rendering pentobarbital-euthanized animals, and 3) the extent to which veterinarians communicate potential relay toxicosis and environmental risks of pentobarbital-euthanized animals to clients. Over a 3-wk period in early 2021, 16,831 of the 99,500 members of the AVMA were surveyed, with 2,093 responses (a 12% response rate). Respondents were assigned to 1 of 3 categories on the basis of their answers: veterinarians euthanizing only food-producing species, veterinarians euthanizing only non–food-producing species, and veterinarians euthanizing both food-producing and non–food-producing species (i.e., veterinarians euthanizing mixed species). Veterinarians responding to this survey appeared to be aware of the major methods of animal disposal, and about 89% reported communicating the method of euthanasia with clients to help ensure appropriate animal disposal. However, the need for additional education on local, state, and federal laws and rendering, as well as on risks of relay toxicosis including wildlife predation and environmental impacts, was reported. Survey results identified gaps in knowledge of veterinarian regarding animal disposal following pentobarbital euthanasia. Further education on this topic may be beneficial, particularly for early- and mid-career veterinarians who euthanize non–food-producing species and for veterinarians who euthanize mixed species in urban and suburban communities.
95 Effects of increasing standardized ileal digestible valine:lysine ratio on growth performance in finishing pigs
Authors: Swanson Samantha , Boschert Andy , Spinler Mikayla , Woodworth Jason C , Tokach Mike D , Goodband Robert D , DeRouchey Joel M , Gebhardt Jordan T
Published: May 2024

Two experiments evaluated the effects of increasing standardized ileal digestible (SID) Val:Lys ratio on the growth performance of 38 to 67 kg (Exp. 1) and 90 to 116 kg (Exp. 2) finishing pigs. In Exp. 1, pigs (n = 647; DNA 600 × 241) were randomly allotted to 1 of 6 dietary treatments with 8 or 9 pigs per pen and 12 replications per treatment. Diets were corn-soybean meal-based, and low and high Val diets were manufactured and blended to create intermediate Val:Lys ratio diets. Diets were formulated to contain 0.90% SID Lys, and treatments consisted of SID Val:Lys ratios of 60%, 63%, 66%, 69%, 72%, and 75%. At the conclusion of the 27-d study, all pigs were fed a common diet for 30 d and then randomly re-allotted to 1 of 6 diets formulated to contain 0.65% SID Lys and SID Val:Lys ratios of 63%, 66%, 69%, 72%, 75%, and 78% (Exp. 2). In both experiments blood samples were collected from 3 pigs per pen on d 15 for plasma urea nitrogen (PUN) analysis. In Exp. 1, final body weight (BW), average daily gain (ADG), and average daily feed intake (ADFI) increased (quadratic, P < 0.05) as Val:Lys increased (Table). Pigs fed the diet with 66% SID Val:Lys ratio had the greatest ADG, whereas pigs fed 72% SID Val:Lys ratio had the greatest ADFI. As the Val:Lys ratio increased, gain to feed ratio (G:F) decreased (linear, P < 0.05). Valine and Lys intake increased (quadratic, P < 0.05) as the Val:Lys ratio increased with the greatest intake observed at 72% SID Val:Lys. Valine and Lys intake per kg of gain increased (linear, P < 0.05) as the level of Val in the diet increased. Plasma urea nitrogen decreased (linear, P < 0.05) as the Val:Lys ratio increased. In Exp. 2, ADG and ADFI increased (linear, P < 0.05) as Val:Lys increased. However, for ADG there was little improvement from feeding greater than 69% SID Val:Lys. There were no linear or quadratic effects (P > 0.05) for SID Val:Lys on G:F or PUN. Valine intake, Lys intake, and Val intake per kg of gain increased (linear, P < 0.05) as the Val:Lys ratio increased. There were no differences (P > 0.05) observed in Lys intake per kg of gain. Based on the results of this study, it appears that 66% SID Val:Lys ratio maximizes ADG in 38to 67 kg pigs, and only small increases in ADG were observed when feeding greater than 69% SID Val:Lys for 90 to 116 kg finishing pigs.
79 Evaluating the effects of increasing levels of sodium diformate on nursery pig performance
Authors: Becker Gracie , Gaffield Katelyn , Tokach Mike D , DeRouchey Joel M , Woodworth Jason C , Goodband Robert D , Lohrmann Troy , Lückstädt Christian , Gebhardt Jordan T
Published: May 2024

Organic acids, such as formic acid, are commonly used as acidifiers in swine diets. Forms of formic acid include salts of sodium, calcium, or potassium. Previous research has shown positive results using potassium diformate in swine diets including improved nutrient digestibility, growth performance, and altered gut microbiota. Additionally, recent data has shown increasing levels of sodium diformate improved growth performance in finishing pigs; however, additional data are needed in nursery pigs. The objective of this study was to investigate the effects of increasing sodium diformate in nursery diets on growth performance. Weanling barrows [n = 360; DNA 200 × 400; initial body weight (BW) = 5.9 ± 0.06 kg] were used in a 38-d study. At weaning, pigs were randomly assigned to pens with 5 pigs per pen. Each pen was randomly allocated to 1 of 6 treatments in a completely randomized design with 12 replicates per treatment. Dietary treatments were formulated to provide none, 0.40, 0.60, 0.80, 1.00, or 1.20% sodium diformate (Formi NDF, ADDCON, Nordic AS, Porsgrunn, Norway) at the expense of corn. Experimental diets were fed in 3 phases: phase 1 from weaning to d 9, phase 2 from d 9 to 24, and phase 3 from d 24 to 38. Feces was collected on d 9 and 24 from 3 pigs per pen to determine fecal dry matter (DM). All data were analyzed using a linear mixed model with treatment as a fixed effect and barn as a random intercept. Contrast statements were used to evaluate the linear and quadratic dose response to increasing sodium diformate inclusion. All statistical models were fit using the GLIMMIX procedure of SAS version 9.4 (Cary, NC). From d 0 to 24 (phase 1 and 2), gain to feed ratio (G:F) increased (linear, P = 0.001) as sodium diformate increased in the diet (Table). However, sodium diformate did not affect (P > 0.10) average daily gain (ADG) or average daily feed intake (ADFI). From d 24 to 38 (phase 3), there was no evidence of differences (P > 0.10) due to increasing sodium diformate for any growth response criteria. For the overall experimental period (d 0 to 38), increasing sodium diformate did not affect (P > 0.10) ADG, ADFI, or G:F. Overall mortality was 0.8% and was not influenced (P > 0.10) by treatment. There was no evidence for differences (P > 0.10) in fecal DM on d 9. However, fecal DM decreased (linear, P < 0.05; quadratic, P = 0.097) as sodium diformate increased in the diet on d 24 with pigs fed 0.40% sodium diformate having the greatest fecal DM. In conclusion, these data suggest increasing levels of sodium diformate has the potential to improve feed efficiency in the early nursey period but did not affect performance in the late nursery.
85 The influence of supplementing isolated or intact structural fiber on the physicochemical properties of digesta and fecal consistency of nursery pigs
Authors: Lloyd Alexis , Pace Bre , Cardona Erick Fuentes , Miller Hannah , Self Rachel , Murphy Isabella , Kellesvig Leah M , Metz Michaela , Petry Amy L
Published: May 2024

In human nutrition, functional fiber refers to isolated non-digestible carbohydrates with physiological roles, while structural fiber pertains to those that are intrinsic and intact in plants. Increasing dietary fiber in post-weaning pig diets has been shown to improve gastrointestinal health and alter fecal consistency. However, minimal research has been conducted on the role of supplementing isolated functional or structural fiber that are chemically insoluble in nursery diets. The experimental objective was to evaluate the effect of functional or structural insoluble fiber supplementation on the physicochemical properties of digesta and feces during the nursery period. A total of 256 newly weaned pigs were randomly assigned to one of four treatments across two replications with 4 pigs per pen and 16 pens per treatment for a 35-d study. The average initial pig body weight (BW) was 5.13 ± 0.65 kg and same sex pens were used and balanced across treatments. Dietary treatments consisted of a control nursery diet (PC), PC with 3% soy hulls (NC), PC with 2% isolated lignocellulose (ISO), and PC with 2% structural lignocellulose (STR). Treatments were fed across phase 1 (d 0-7) and phase 2 (d 7-21) diets, and a common diet was fed in phase 3 (d 21-35). On d 7, 14, 21, 28, and 35, fresh fecal samples were collected to determine water binding capacity (WBC), water swelling capacity (WSC), and fecal dry matter (DM). Fecal scores were also evaluated using a predefined scale (1 = solid; 4 = liquid). On d 21, one pig per pen closest to the mean BW was necropsied, and ileal, cecal, and colonic digesta were collected. Continuous data were analyzed as a linear mixed model (PROC MIXED) with treatment, sex, and period as fixed effects, replicate as a random effect, and initial BW as a covariate where appropriate. Fecal scores were analyzed using a multinomial model in PROC GENMOD and FREQ. Pigs fed ISO and STR tended to have greater fecal DM (24.1%, 24.6%, 25.4%, and 26.29% for PC, NC, ISO, and STR, respectively; P = 0.071). There was a greater proportion of solid and semi-solid feces in pigs fed ISO (P = 0.039). Fecal WBC was greatest in pigs fed PC, with NC and ISO performing intermediately, and STR having the least (2.66, 2.55, 2.50, and 2.39 mL/g of DM for PC, NC, ISO, and STR, respectively; P = 0.071). Fecal WSC increased with time (P < 0.001), but there was no impact of treatment (P = 0.983). Ileal digesta pH was decreased in NC and STR, relative to PC and ISO, (P = 0.007). There tended to be a similar response for cecal pH (P = 0.092). Pigs fed PC tended to have the greatest colonic WBC (P = 0.058). Collectively, supplementing isolated or structural lignocellulose can alter the physicochemical properties of nursery pig feces.
89 Evaluation of repeatability of anogenital distance measured with either a caliper or photogrammetry
Authors: Olalde Andres , Ewing Kylie P , McCann Joshua C , Shike Daniel W W
Published: May 2024

The objective was to determine the repeatability of anogenital distance (AGD) measurements over time in growing heifers and evaluate the relationship of photogrammetric and caliper AGD measurements. Reproductive success is one of the most important determinants of profitability in the beef industry. However, fertility traits generally have low heritability, and there are few phenotypic traits that correlate to fertility in beef cattle. The AGD is the distance from the center of the rectum to the base of the clitoris. Recently, researchers in dairy cattle have reported a correlation between shorter AGD and improved fertility. In the published dairy research, AGD has been measured with the use of calipers. Photogrammetric measurement could be a quicker and safer way of taking the measurement and easier to implement on farm. Heifers (n = 153), either Angus or Hereford sired by commercial dams, were used in the analysis. Heifers were early weaned at 82 ± 7 d of age. Following weaning, heifers were managed in partially covered, dry lot pens and fed a moderate roughage growing diet. The heifers rotationally grazed predominantly tall fescue pastures beginning in April of 2023. Heifer AGD was evaluated monthly from June to September. Heifers weighed 210 ± 22 kg and 282 ± 6 d of age at the time of the first AGD measurements. Heifer body weight was collected monthly at time of AGD measurements. The heifers were restrained in a squeeze chute and had their tail held in a relaxed upright position and AGD was measured with a caliper. Immediately following caliper measurements, anogenital photographs were taken with an Iphone 14 plus. A white board with a forensic photomacrographic scale attached and the ear tag number recorded on the right corner was held adjacent to the vulva and was included in the photograph. Photographs were converted from HEIC to JPEG. A software program, Digitizer, was used to set the measurement scale using the forensic photomacrographic scale. The AGD was then digitally measured from the center of the rectum to the base of the clitoris. Repeatability of AGD and relationship of caliper and photogrammetric AGD were evaluated using the CORR procedure of SAS 9.4. Caliper AGD measurements were repeatable as all of the time points were moderately correlated (r ≥ 0.47; P ≤ 0.01) throughout the evaluation period. Photogrammetric AGD measurements were also repeatable as all of the time points were correlated (r ≥ 0.21; P ≤ 0.02) throughout the evaluation period. Photogrammetric AGD had a moderate correlation (r ≥ 0.44; P ≤ 0.01) with the caliper AGD measurements. In conclusion, AGD measurements were repeatable in growing heifers regardless of measurement method. Photogrammetric measurements may be a viable option for estimating AGD as they were strongly correlated to caliper measurements of AGD.
91 The effect of increasing oat groat levels on nursery pig performance, digesta pH, and fecal consistency and physicochemical properties in young pig diets
Authors: Pace Bre , Lloyd Alexis , Murphy Isabella , Miller Hannah , Petry Amy L
Published: May 2024

Post-weaning growth delay in pigs is a well-documented challenge associated with the stressors inherent in the weaning process. Oat-based dietary interventions have shown potential in improving fecal consistency, increasing feed intake, and improving feed efficiency. However, the direct effect of oat groats on the fecal physicochemical properties and dry matter (DM) is largely unknown. The experimental objective was to evaluate increasing inclusions of oat groats in young pig diets on pig performance, digesta pH, and fecal consistency and physicochemical properties. Newly weaned pigs (n = 128) with an initial body weight (BW) of 5.4 ± 0.27 kg were randomly assigned to one of four treatments (n = 8 split sex pens) for a 35-d study. Dietary treatments consisted of 0%, 5%, 10% or 15% inclusion of oat groats at the expense of corn. Treatments were applied across 2 dietary phases and a common diet fed during phase 3: d 0-7 (phase 1), d 7-21 (phase 2), d 21-35 (phase 3). On d 7, 14, 21, 28, and 35, pigs and feeders were weighed, pen fecal samples were collected, and fecal scores were evaluated using a 4-point scale (1 = solid, 2 = semi-solid, 3 = semi-liquid, 4 = liquid). Fresh fecal samples were analyzed for water binding capacity (WBC), and fecal DM. On d 14, one pig per pen closest to the mean BW was necropsied, and ileal, cecal, and colonic digesta pH were measured. Continuous data were analyzed as a linear mixed model (PROC MIXED) with treatment and period as fixed effects, and initial BW as a covariate where appropriate. Orthogonal polynomial contrasts were used to determine the linear and quadratic effects of increased inclusion. Fecal scores were analyzed using odd logistic regression. There was a linear increase in average daily gain (ADG) and average daily feed intake (ADFI) as oat groat inclusion increased from d 0-7 and d 7-14 (Linear P < 0.05). However, from d 14 to 21, and d 21 to 35 there was no longer an impact of oat inclusion on ADG (P > 0.782) or ADFI (P > 0.405). Feed efficiency did not differ among treatments (P > 0.71). Oat groat inclusion had no effect on fecal scores throughout the study (P = 0.743). However, fecal DM% increased as oat groat inclusion did on d 7 and 14 (Linear P < 0.01), and fecal WBC tended to be increased in 5% and 10% oat groat diets (Diet; P = 0.063). Ileal and colonic pH did not differ among treatments, but cecal pH tended to be less in pigs fed 10 and 15% oat groats (P = 0.089). In conclusion, increasing oat groats in nursery diets increased ADFI, ADG, and altered fecal DM, but did not impact feed efficiency.
81 Effects of udder quarter location on colostrum yield, nutrients, and immunoglobulin G in beef heifers
Authors: Caple Jessalyn E , Rathert-Williams Abigail R , Redifer Colby A , McFadden Thomas B , Meyer Allison M
Published: May 2024

We hypothesized that colostrum total nutrients and immunoglobulin G (IgG) would not be affected by side of the udder, but that they would be greater in the rear versus the front half of the udder due to difference in volume of colostrum produced. Complete colostrum yield was collected individually from each quarter pre-suckling [40.5 ± 21.0 min (SD)] from fall-calving crossbred beef heifers (body weight = 472 ± 34 kg; body condition score (= 5.3 ± 0.4) that were either individually-fed 100% (control; n = 12) or 70% (nutrient restricted; n = 12) of NASEM metabolizable energy and metabolizable protein requirements from d 160 of gestation to calving. Analysis of colostrum lactose, protein, triglycerides, and free glucose was performed using colorimetric assays on a UV-visible light microplate reader. Colostrum IgG was analyzed using a commercially available ELISA kit. Quarter yield, nutrient or IgG concentration, and total nutrients or IgG were analyzed using the mixed procedure of SAS with fixed effects of udder location, nutritional plane, and their interaction in the model. Nutritional plane was not part of the current objective, but was included to account for variation in colostrum yield due to nutrient restriction, as we have previously reported. Separate statistical comparisons were made between the front and rear quarters and between the right and left quarters of the udder, with each quarter considered a sampling unit within each experimental unit (half) for both analyses. The interaction of udder location × nutritional plane did not affect (P ≥ 0.11) any variable. Nutrient restriction decreased (P ≤ 0.03) colostrum yield, total lactose, and total free glucose compared with controls. Front quarters produced less volume (P < 0.001; 36.2% of total); total lactose, protein, and free glucose (P ≤ 0.02; 34.3 to 43.3%); and total IgG (P < 0.001; 33.7%) than rear quarters. Front quarters tended to produce less (P = 0.07; 43.3%) total triglycerides than rear quarters. Lactose concentration was 10.5% greater (P = 0.05) in front compared with rear quarters, but other nutrient or IgG concentrations were not affected (P ≥ 0.18). Udder side did not affect total volume (P = 0.78), total nutrients (P ≥ 0.36), or total IgG (P = 0.79). The left side represented 50.7% of the total volume and 50.1 to 53.4% of total nutrients and IgG produced. Concentration of nutrients and IgG also were not affected (P ≥ 0.31) by udder side. In conclusion, colostrum did not differ between udder sides, but, relative to front quarters, rear quarters produced greater nutrient and IgG yield due to greater colostrum volume with minimal differences in nutrient or IgG concentrations.
90 Evaluating water- and feed-based arginine supplementation on newly weaned pig growth and gastrointestinal health
Authors: Bohr Ayva , Hagen Chloe S , Haydon Keith D , Greiner Laura L
Published: May 2024

The objective of this experiment was to assess the influence of arginine (Arg) supplementation in water and/or feed on the growth performance and gastrointestinal health of newly weaned pigs. Pigs (n = 240; PIC 337 Χ 1050, Genus, Henderson, TN) were randomly allocated into 80 mixed-sex test pens and subjected to a 2 Χ 4 factorial design, with two levels of Arg supplementation in water (0% or 8% stock, dosed through a 1:128 proportioner) for the first phase (d 0-7), and four dietary arginine levels (0.85, 0.95, 1.05, and 1.15 standardized ileal digestible (SID) Arg to Lysine (Lys) ratios for the first two phases (d 0-7 and 7-21). All treatments were provided a common diet (0.96 SID Arg:Lys) for the last phase d 21- 42. One pig per pen underwent a dual sugar absorption test of lactulose at 500 mg/kg and mannitol at 50 mg/kg of body weight (BW) via gastric tube on d 7 and 21, with blood plasma collected 4 h post-administration. The pig tested on d 7 was subsequently euthanized for intestinal tissue collection. Pen growth performance and feed disappearance were evaluated for 3 phases; d 0-7, 7-21, and 21-42. The statistical analysis utilized generalized linear mixed model methods (SAS 9.4, Cary, NC) with the main effects of SID Arg:Lys in the feed and Arg level within the water, and the interaction between the two. Pen was the experimental unit. Orthogonal contrasts were tested for the linear and quadratic effects of the diet. Growth performance during the 1st period exhibited variability, reflected by negative gain to feed ratio (G:F), caused by health challenges of Rotavirus A. Consequently, data were analyzed separately for each phase. Increasing dietary SID Arg:Lys caused a significant linear effect (improvement; P = 0.04) on final BW (18.47 and 21.90 kg, for 0.85 and 1.15 SID Arg:Lys, respectively). However, discernible differences between dietary treatments were not observed (P > 0.1). Similarly, a trend (P = 0.09) suggested a linear impact of dietary SID Arg:Lys on average daily gain during the third phase (d 21-42). In terms of intestinal absorption and morphology, Arg supplementation, whether through water or diet, had no effect on lactulose and mannitol absorption on both d 7 and d 21, nor did it impact villous height, crypt depth, or the villi:crypt ratio in ileum tissues collected on d 7 post-weaning. In conclusion, dietary supplementation with Arg increased final BW but had no clear impacts on intestinal health within the variables measured, potentially impacted by the rotavirus diagnosis in the first week post wean.
80 Substitution of dried distiller’s grains with soybean meal on beef cattle diets: Effects on ruminal ammonia and volatile fatty acid concentrations
Authors: Macholan Natasha L , Jardon Grace , Colombo Elissa , Smith Zachary K , Rusche Warren C , Menezes Ana Clara Baiao
Published: May 2024

The objective of this study was to evaluate the effects of substitution of dried distiller grains with soybean meal on beef cattle diets in ruminal ammonia and volatile fatty acid (VFA) concentrations. Red Angus steers [n = 4; body weight (BW) = 360 ± 9 kg] with ruminal, duodenal, and ileal cannulas, were used in a 4 × 4 latin square. Diets (TMR) consisted of dry-rolled corn (70%), hay (10%), liquid supplement (5%), and test ingredients (15%). Treatments were [dry matter (DM) basis]: 1) 15.0% DDGS (CON); SBM in replacement of 50% of DDGS (SBM50); SBM in replacement of 75% of DDGS (SBM75), and SBM in replacement of 100% of DDGS (SBM100). Each period lasted 18-d, consisting of a 7-d diet adaptation followed by an 11-d collection period. Rumen fluid was collected at -2, 0, 2, 4, 6, 8, 10, and 12 h post-feeding on d 16. Ruminal digesta was strained through two layers of cheesecloth and two 10-mL aliquots of ruminal fluid were collected and stored at −20°C until further analysis of ammonia and VFA concentrations. Data were analyzed as repeated measures using the MIXED procedure of SAS with treatment, sampling time, and their interaction as fixed effects, and animal and period as random effects. No treatment by day interactions (P ≥ 0.84) were observed for ammonia or VFA. Ammonia concentrations were greater (P ≤ 0.01) for SBM75 compared with SBM100 and CON, with intermediate values observed for SBM50 (Table 1). Moreover, ammonia was greater (P ≤ 0.01) at 0h compared with 6, 8, and 12h post-feeding. Acetate was greater (P ≤ 0.01) for SBM75 and SBM100 compared with CON and SBM50. Concentrations of propionate were greatest (P ≤ 0.01) for SBM100 and least for CON, with SBM50 and SBM75 being intermediate. Further, propionate was greater (P ≤ 0.01) at 16h compared with 0 and 2 h post-feeding, with all other times being intermediate. Isobutyrate was less (P ≤ 0.01) for CON than all other treatments, and greater concentrations (P ≤ 0.01) were observed at -2 compared with 14 and 16 h post-feeding. Butyrate was greatest (P ≤ 0.01) in SBM75, followed by CON and SBM50; SBM50 was similar to SBM100. Butyrate concentrations were similar -2 and 0 h post feeding, which were less (P ≤ 0.01) than all other times. Isovalerate was greater (P ≤ 0.01) for CON than SBM50 and SBM75, and similar to SBM100. Valerate was greatest (P ≤ 0.01) for SBM75 and SBM100 followed by SBM 50 and CON which had the least valerate value. Overall, our results show that SBM75 resulted in greater concentrations of ammonia, acetate, propionate, butyrate, isobutyrate, and valerate compared with CON. These data suggest that 75% substitution of DDGS with SBM has the potential to optimize microbial fermentation. To complement these results, we are currently evaluating rumen protein degradation profiles and amino acid flow to small intestine.
88 Ruminal degradation profiles of dry matter, organic matter, and crude protein of finishing diets with different levels of inclusion of dried distiller’s grains plus solubles and soybean meal
Authors: Moening Katherine M , Jardon Grace , Colombo Elissa , Smith Zachary K , Rusche Warren C , Menezes Ana Clara Baiao
Published: May 2024

The objective of this study was to estimate the ruminal degradation profile of dry matter (DM), organic matter (OM), and crude protein (CP) in concentrate-based diets with different levels of inclusion of dried distiller’s grains plus solubles (DDGS) and soybean meal (SBM). Red Angus steers [n = 4; body weight (BW) = 360 ± 9 kg] with ruminal, duodenal, and ileal cannulas, were used in a 4 × 4 latin square. Diets (TMR) consisted of dry-rolled corn (70%), hay (10%), liquid supplement (5%), and test ingredients (15%). Treatments were (DM basis): 1) 15.0% DDGS (CON); SBM in replacement of 50% of DDGS (SBM50); SBM in replacement of 75% of DDGS (SBM75), and SBM in replacement of 100% of DDGS (SBM100). Each period lasted 18-d, consisting of a 7-d diet adaptation followed by an 11-d collection period. An in situ ruminal incubation of each TMR was performed from d 8 to 11 of each period. Ingredients were weighed separately, maintaining their proportion in the TMR. Air-dried TMR sample (6 g, 2 mm grind) was ruminally incubated in a nylon bag (Ankom, 10 × 20 cm) using the same steer from the in vivo study. Samples were incubated for 0, 2, 4, 8, 16, 24, 48, and 72 h. The number of bags varied as a function of the incubation time to guarantee enough residual samples after incubation, where more bags per sample were incubated for the longer incubation times relative to the shorter incubation times (72 and 48 h, n = 5; 24 h, n = 4; 16 h, n = 3; 8 h and 4 h, n = 2; 2 h and 0 h, n = 1). DM, OM, and CP degradation were estimated by using the following model: Yt = a + b × (1 − e(−kd × t)), The NLIN procedure of SAS 9.4 was used and restricted and full models were compared by a likelihood ratio test. Rumen degradable protein (RDP) of each TMR was calculated as follows: RDP = a + b + [kd/(kd + kp)], where kp was 0.05 h−1). There were no differences (P ≥ 0.47) on the fractions a, b, and kd, or RDP (55%) between treatments for DM, OM, and CP. According to our analysis, approximately 13 h of incubation is necessary to accurately estimate the RDP content of the TMR. The NASEM (2016) adopts 35 and 75% of RDP for DDGS and SBM, respectively, based on fixed incubation time of 16 h. Most studies have evaluated degradation profiles of individual feed and not TMR; however, animals are fed complete diets, made up by feedstuff that vary in physical characteristics, nutrient composition, and consequently RDP. In this study, the similar degradation profiles between diets suggest that RDP of complete diets differs from that of individually assayed ingredients.
83 Effect of stocking density on F1 gilt reproductive performance
Authors: Henry Clara K , Self Rachel , McNeil Brady , Cross Amanda , Stephenson Ethan , Mainquist-Whigham Christine
Published: May 2024

Replacement females are the future of a farm, and their development can impact production. Currently, replacement gilts are housed in many different environments. Stocking density of replacement females is one factor that varies across production systems. Therefore, the objective of this study was to evaluate the effect of different stocking densities on replacement gilt reproductive performance. At 10 wk of age, DNA L241 females (n = 824; DNA Genetics, Columbus, NE) were randomly allotted to finishing pens with 3 different stocking densities. Each stocking density consisted of 12 pens of 0.71 m2 (n = 360), 0.93 m2 (n = 264), and 1.25 m2 (n = 204). Heat detection started at 20 wk of age with fence line exposure for 2 wk at 15 minutes per pen. Within pen boar exposure occurred from 22 to 31 wk of age for a minimum of 10 min per pen. Starting at 20 wk of age, females that exhibited red and swollen vulvas or standing estrus were recorded. Body weight, backfat, and loin depth measurements were collected at estrus detection. A blood progesterone assay was performed on all females at 24 wk of age. Further blood progesterone assays were performed at 27, 29 and 31 wk of age on any female for which progesterone was not detected on previous assays. Females were mated on their 2nd estrus if they were at least 136 kg or on their first estrus if they were over 145 kg. Body weight was recorded at the time of mating. For females that cycled by 31 wk, females in the 0.71 m2 treatment cycled significantly earlier than the 0.93 m2 treatment, 147 vs 153 d post-weaning respectively (P < 0.05). No difference was detected in age at mating; however, gilts in the 0.71 m2 treatment were 5.9 kg and 8.2 kg lighter than the 0.93 and 1.25 m2 treatments respectively (P < 0.01). At 31 wk of age 60% of the 0.71 m2, 71% of the 0.93 m2, and 77% of the 1.25 m2 treatments had cycled according to visual heat detection. However, according to the progesterone assay, at 31 wk of age 75% of 0.71 m2, 81% of the 0.93 m2, and 84% of the 1.25 m2 had cycled. The accuracy of visual heat detection compared with progesterone assay were 79.4% for 0.71 m2, 77.3% for 0.93 m2, and 85.8% for 1.25 m2 treatments. Overall, the 1.25 m2 treatment resulted in heavier females at mating, a greater rate of females cycling, and a more accurate detection of females cycling than the 0.71 m2 treatment. Swine producers can improve the percentage of females detected in estrus and mated in the desired period by providing additional rearing space during gilt development.
92 Factors influencing bull selection in Illinois beef producers: Analysis of retained and non-retained ownership producers
Authors: Rincker Grace E , McCann Joshua C , Shike Daniel W W , Meteer William T
Published: May 2024

The objective was to understand decision-making factors for bull selection of producers participating in the Illinois Performance Tested (IPT) bull sale. The IPT bull sale has served Illinois beef producers for the last 54 yr offering around 50 bulls annually. A comprehensive survey targeted a diverse group of beef producers that had previously attended the IPT bull sale. The survey was developed through Qualtrics and provided to producers via email. The survey consisted of 40 questions based on four categories: farm location, herd demographics, bull selection criteria, and feedback from previous experiences at the IPT bull sale. There were a variety of question types including multiple choice, select all that apply, open-ended, ranking of importance, and select on a scale from one to ten. Specific responses on bull selection criteria focused on expected progeny differences and functional traits. Survey results were grouped based on whether producers retained ownership of feedlot cattle; regularly retained ownership (RET; n = 12) and never retained ownership (NRET; n = 15). Data were analyzed with the MIXED and GLIMMIX procedures of SAS 9.4. For RET and NRET producers, there were no observed differences in mature cow body weight and herd size (P ≥ 0.42). Most producers responded that they calved in March and April. Producer groups did not differ (P = 0.99) in the percentage of respondents retaining replacement heifers, as 66% of RET and NRET producers retained replacements. However, RET producers tended to be more likely (P = 0.07) to regularly sell freezer beef. Specifically, 75% of RET producers regularly sell freezer beef compared with 13% of NRET producers. Additionally, RET producers tended to prioritize (P = 0.1) carcass trait expected progeny differences in bull selection more than NRET producers (66 vs 33%, respectively). There was no difference (P = 0.2) in the percentage of respondents that selected the weaning weight expected progeny difference in their top three traits. However, NRET producers were much more likely (P < 0.01) to prioritize yearling weight expected progeny difference in their bull selection decisions. Specifically, 66% of RET producers used yearling weight expected progeny difference in their bull selection compared with 0% of NRET producers. Lastly, there was no difference (P = 0.61) in the percentage of respondents who included docility in their top three functional traits. In conclusion, bull buyers at the IPT bull sale that regularly retain ownership of feedlot cattle were more likely to prioritize expected progeny differences for yearling weight and carcass traits while functional traits priorities were similar to producers that did not retain ownership of feedlot cattle.
87 Evaluating the effects of an amino acid-formulated diet on ruminal fermentation in vitro
Authors: Merritt McKenna , Linder Haley F , Cecava Michael J , McCann Joshua C
Published: May 2024

The objective was to determine the effect of an amino acid-formulated diet on ruminal fermentation in vitro. While most amino acid-formulated diets focus on improving the amino acid composition of rumen undegradable protein, additional benefits to microbial fermentation within the rumen are unknown. The experiment was a completely randomized design with a factorial treatment arrangement (2 donor diets and 2 substrates). Four ruminally cannulated steers were fed one of two donor diets: control (CON; 55% dry rolled corn, 20% corn silage, 15% dry distiller’s grain, and 10% supplement) and amino acid-formulated (AAF; 51% dry rolled corn, 15% corn silage, 14% dry distillers grain, 10% heat-treated soybean meal, and 10% supplement). After a 30-d diet adaptation period, rumen fluid was collected and pooled by donor diet for the in vitro fermentation. Additionally, two different substrates were used to represent each donor diet. Flasks contained 2.5 g dry matter (DM) of substrate and 150 mL of rumen fluid mixture (2 McDougall’s buffer:1 rumen fluid). Treatments were evaluated in triplicate flasks in two replicated runs for a total of six observations per treatment. Four sealed Ankom F57 bags were filled with 0.25 g DM of substrate each to facilitate measuring in vitro DM disappearance (IVDMD). Flasks were incubated at 39°C with sample aliquots collected at h 0, 4, 8, 12, and 24 to determine pH, ammonia, and volatile fatty acids (VFA). Data were analyzed using the MIXED procedure of SAS 9.4 with a repeated measures analysis. Ammonia, pH, and VFA were analyzed with effects of donor diet, substrate, time, and all interactions. A treatment by hour interaction was detected (P < 0.01) for pH; fluid from steers fed CON was greater than AAF at h 4, 8, 12, and 24. A treatment by hour interaction was also detected (P = 0.02) for ammonia; fluid from steers fed CON was greater than AAF at h 24, but was not different at other time points. Total VFA was affected by hour (P < 0.01) as it increased over time, but substrate did not have an effect (P = 0.21). A treatment by hour interaction (P = 0.06) tended to be observed for molar proportions of acetate as AAF and CON were similar at h 0 but AAF was increasing greater than CON over time. A treatment by hour interaction was observed (P = 0.01) for molar proportions of propionate; at h 4 at 8, CON was greater than AAF. No effect (P ≥ 0.32) of donor diet, substrate or their interaction were observed on IVDMD. Overall, an amino acid-formulated diet for cannulated steers did impact ruminal fermentation in vitro, mostly altering molar proportions of volatile fatty acids and ammonia release from protein degradation.