US Swine Industry Research Articles

38 Pig survival: Current state of the US swine industry

Abstract 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.

139 Effect of dietary crude protein concentration and sensory feed additive on nursery pig growth performance

Abstract Maximizing growth performance and feed intake for nursery pig diets is an ongoing challenge in the US swine industry. Using sensory feed additives is one strategy to optimize feed intake and growth rates of pigs. Weanling pigs (n = 416; average age = 19.8 d) were used to test the effects of sensory feed additive (SA; Luctamax Piglet, Lucta, Mahwah, NJ) addition to control (CON) and low crude protein (LCP; decreased 4% CP) nursery diets in a 2 x 2 factorial design (CON, CON+SA, LCP, LCP+SA). Decreased dietary CP was achieved by removing or decreasing fish meal and soy concentrate in phases 1 and 2 and reducing soybean meal in phase 3 and adding synthetic amino acids to maintain amino acid ratios (NRC 2012). Nursery treatments were fed in three phases; phase 1 (PH1, d 0-7, 0.10% SA), phase 2 (PH2, d 7-21, 0.10% SA), and phase 3 (PH3, d 21-36, 0.05% SA). Pigs were blocked by initial body weight (BW), sex, ancestry, and housed at 6 or 7 pigs/pen with 15 pens/treatment. Weekly pig BW and feed intake were used to calculate pen average daily gain (ADG), average daily feed intake (ADFI), and gain to feed ratio (G:F). Data were analyzed using GLM procedure of SAS 9.4. During PH1 pigs receiving the CON diets tended (P = 0.065) to have a greater G:F compared with pigs receiving LCP diets. For the remainder of this study there were consistent interactions between dietary CP and SA. When SA was added to the LCP diet ADFI increased but when SA was added to CON diet ADFI decreased and these changes in feed intake often led to similar dietary interactions in ADG. During PH2, pigs fed CON or LCP+SA diets had greater ADFI (P = 0.032) and tended to have a greater ADG (P = 0.094) but reduced G:F (P = 0.100) compared with pigs fed CON+SA or LCP diets. In PH3, pigs fed CON or LCP+SA diets had a greater ADG (P = 0.027) and ADFI (P = 0.011) compared with CON+SA or LCP diets. Pigs fed LCP diets had greater ADFI (P = 0.001) but reduced G:F (P = 0.0001) than pigs fed CON diets. Overall, pigs fed CON or LCP+SA diets had greater ADFI (P = 0.016) and tended to have a greater ADG (P = 0.059) but reduced G:F (P = 0.067) compared with pigs fed CON+SA or LCP diets. Pigs fed CON diets had a greater G:F (P < 0.001) compared with pigs fed LCP diets, while LCP pigs tended to have a greater ADFI (P = 0.054) compared with CON pigs. Inclusion of SA to LCP diet mitigated the adverse impact of replacing whole dietary proteins with high inclusion of synthetic amino acids. Careful consideration is needed when using sensory feed additives so as not to impede growth performance in diets containing traditionally greater levels of crude protein.

The evolving US swine industry

The US swine industry has evolved toward large, integrated production systems and increased efficiency and sustainability, which also impacted disease ecology. A survey assessed the diversity of US barn sizes and pen designs. This report describes the results and discusses factors that may promote disease persistence in these changing conditions.

Biosecurity Insights from the United States Swine Health Improvement Plan: Analyzing Data to Enhance Industry Practices.

Biosecurity practices aim to reduce the frequency of disease outbreaks in a farm, region, or country and play a pivotal role in fortifying the country's pork industry against emerging threats, particularly foreign animal diseases (FADs). This article addresses the current biosecurity landscape of the US swine industry by summarizing the biosecurity practices reported by the producers through the United States Swine Health Improvement Plan (US SHIP) enrollment surveys, and it provides a general assessment of practices implemented. US SHIP is a voluntary, collaborative effort between industry, state, and federal entities regarding health certification programs for the swine industry. With 12,195 sites surveyed across 31 states, the study provides a comprehensive snapshot of current biosecurity practices. Key findings include variability by site types that have completed Secure Pork Supply plans, variability in outdoor access and presence of perimeter fencing, and diverse farm entry protocols for visitors. The data also reflect the industry's response to the threat of FADs, exemplified by the implementation of the US SHIP in 2020. As the US SHIP program advances, these insights will guide industry stakeholders in refining biosecurity practices, fostering endemic re-emerging and FAD preparedness, and ensuring the sustainability of the swine industry in the face of evolving challenges.

186 Examining the Vaginal Microbiome During Gilt Reproductive Development

Abstract Gilt reproductive failure is a common challenge in the US swine industry. Indeed, as many as three million breeding females are removed from swine herds each year, resulting in an annual replacement rate of 40%. Furthermore, about 20% of gilts selected for replacement never successfully enter the reproductive herd. The vaginal microbiome may play a role in gilt reproductive success; this study compared the vaginal bacterial composition from eight gilts at two pre-pubertal time points (d70 and d130 of age). Vaginal swabs were collected and analyzed using the 16S rRNA gene through PCR-amplification of the V1-V3 regions from vaginal microbial genomic DNA, followed by Illumina MiSeq 2X300 sequencing. Seven of the gilts achieved first estrus between d 164 and d 190 days of age based on physical signs of vulva swelling and locked stance in the presence of a boar. One female had no visible signs of estrus before 210 d of age. Beta diversity analysis by PCoA revealed that samples clustered into two separate groups according to time points. Alpha diversity indices (Sobs, Ace and Chao) were numerically decreased between d 70 to d 130. A comparative analysis of the most highly represented Operational Taxonomic Units (OTUs) using the non-parametric Kruskal-Wallis sum-rank test and Wilcoxon pairwise test identified 12 OTUs that varied in abundance (P < 0.05) between the two time points. Notably, OTU SD_Ssd-00001, predicted to be a strain of Lactobacillus amylovorus (99.82% sequence identity), was greatest at d 70 (21.33%), then significantly decreased at d 130 (7.67%). In contrast, OTU SD_Ssd-01393, corresponding to an uncultured species of Prevotellaceae (closest relative: Prevotella disiens, 92.48%), was in less abundance at d 70 (4.87%), but became the most abundant OTU at d 130 (18.19%). The vaginal OTUs identified in this study included not only known bacterial species, such as members of the Lactobacillus genus which have been previously found to be normal and beneficial residents of the human vagina, but also uncharacterized bacterial species. These results are indicative of distinct vaginal microbiome composition between d 70 and d 130 of age and suggest that certain bacterial species could potentially be used as indicators of reproductive potential in gilts.

257 Survey of Biological Measurements Used to Determine Bone Mineralization in Pigs Across the US Swine Industry

Abstract Pigs (n = 192) from 64 commercial sites across 14 production facilities in the Midwest USA were used to evaluate baseline biological measurements used to determine bone mineralization in pigs. There were 3 pigs selected from each site representing: 1) a clinically normal pig, 2) a pig with evidence of clinical lameness, and 3) a pig with a history of recent low feed intake within a hospital pen (sick pig). Pigs ranged in age from nursery to market weight, with the three pigs sampled from each site representing the same phase of production. For each pig, blood, urine, and the right and left metacarpal, fibula, 2nd rib, and 10th rib were collected and analyzed. Serum was analyzed for Ca, P, and 25(OH)D3 as part of the serum chemistry profile. and. Each bone was measured for bone density and ash (non-defatted and defatted methods). Bone density was measured on each bone based on Archimedes principle. For defatted bone ash, all bones were cleaned of tissue and then placed in Soxhlet extractors containing petroleum ether for 7 days as a means of removing water and fat. Bones were then dried at 105°C for 7 days and then ashed in a muffle furnace at 600°C for 24 h. Healthy pigs had increased (P < 0.05) serum calcium and 25OHD3 compared with sick pigs, with lame pigs intermediate (Table). Healthy pigs also had increased (P < 0.05) serum phosphorus compared with sick and lame pigs, with no differences between the sick and lame pigs. For defatted bone ash and bone density, there was a pig type × bone interaction (P < 0.001). There were no differences between pig types for the fibulas, 2nd rib, and 10th rib, but metacarpals from healthy pigs had greater bone ash compared with sick pigs, with lame pigs intermediate. For bone density, healthy and lame pigs had greater (P < 0.05) bone density than sick pigs for the metacarpals and fibulas, with no difference observed for the ribs. In summary, there appear to be differences in serum analysis between a healthy, lame, and sick pig. Differences in bone mineralization between pig types were observed in the metacarpal and fibula, but not ribs. The metacarpal appears to be the most sensitive bone to detect differences in bone mineralization between pig types. There was also considerable range in values within pig type across production sites.

US Swine Industry Stakeholder Perceptions of Precision Livestock Farming Technology: A Q-Methodology Study.

This study used the Q-methodology approach to analyze perceptions of precision livestock farming (PLF) technology held by stakeholders directly or indirectly involved in the US swine industry. To see if stakeholders' perceptions of PLF changed over time as PLF is a rapidly evolving field, we deliberately followed up with stakeholders we had interviewed 6 months earlier. We identified three distinct points of view: PLF improves farm management, animal welfare, and laborer work conditions; PLF does not solve swine industry problems; PLF has limitations and could lead to data ownership conflict. Stakeholders with in-depth knowledge of PLF technology demonstrated elevated levels of optimism about it, whereas those with a basic understanding were skeptical of PLF claims. Despite holding different PLF views, all stakeholders agreed on the significance of training to enhance PLF usefulness and its eventual adoption. In conclusion, we believe this study's results hold promise for helping US swine industry stakeholders make better-informed decisions about PLF technology implementation.

Will swine veterinarians lead by meeting the next-generation needs of our industry?

The US swine industry is currently challenged by the potential of transboundary animal disease (eg, African swine fever) entry to the national herd and the relentless pressures of domestic diseases (eg, porcine reproductive and respiratory syndrome). The task of the swine veterinarian is to biosecure both the national herd and their customers' local farms to mitigate these risks. This Viewpoint raises 4 questions that swine veterinarians, including practicing (private and corporate), industry, research, academic, and regulatory (state and federal) veterinarians who spend a portion of their time controlling, treating, preventing, or eradicating diseases of swine, must answer to meet the needs of their farms to compete globally and survive. In addition, it appears that there is sufficient science-based information to move forward in a collaborative manner and that the goals of prevention of African swine fever and elimination of porcine reproductive and respiratory syndrome virus are technically possible. Therefore, as previous generations of swine veterinarians led the US industry in the elimination of foot-and-mouth disease virus, classical swine fever virus, and pseudorabies virus from the national herd, the central challenge is whether the next generation of veterinarians will provide the necessary leadership to deal with the current industry and its next-generation challenges.

Diagnostic Survey of Biological Measurements Used to Determine Bone Mineralization in Pigs Across the US Swine Industry

Diagnostic Survey of Biological Measurements Used to Determine Bone Mineralization in Pigs Across the US Swine Industry

Comparative Analysis of Novel Strains of Porcine Astrovirus Type 3 in the USA.

Porcine astrovirus type 3 (PoAstV3) has been previously identified as a cause of polioencephalomyelitis in swine and continues to cause disease in the US swine industry. Herein, we describe the characterization of both untranslated regions, frameshifting signal, putative genome-linked virus protein (VPg) and conserved antigenic epitopes of several novel PoAstV3 genomes. Twenty complete coding sequences (CDS) were obtained from 32 diagnostic cases originating from 11 individual farms/systems sharing a nucleotide (amino acid) percent identity of 89.74–100% (94.79–100%), 91.9–100% (96.3–100%) and 90.71–100% (93.51–100%) for ORF1a, ORF1ab and ORF2, respectively. Our results indicate that the 5′UTR of PoAstV3 is highly conserved highlighting the importance of this region in translation initiation while their 3′UTR is moderately conserved among strains, presenting alternative configurations including multiple putative protein binding sites and pseudoknots. Moreover, two predicted conserved antigenic epitopes were identified matching the 3′ termini of VP27 of PoAstV3 USA strains. These epitopes may aid in the design and development of vaccine components and diagnostic assays useful to control outbreaks of PoAstV3-associated CNS disease. In conclusion, this is the first analysis predicting the structure of important regulatory motifs of neurotropic mamastroviruses, which differ from those previously described in human astroviruses.

Integrating animal movements with phylogeography to model the spread of PRRSV in the USA.

Viral sequence data coupled with phylodynamic models have become instrumental in investigating the outbreaks of human and animal diseases, and the incorporation of the hypothesized drivers of pathogen spread can enhance the interpretation from phylodynamic inference. Integrating animal movement data with phylodynamics allows us to quantify the extent to which the spatial diffusion of a pathogen is influenced by animal movements and contrast the relative importance of different types of movements in shaping pathogen distribution. We combine animal movement, spatial, and environmental data in a Bayesian phylodynamic framework to explain the spatial diffusion and evolutionary trends of a rapidly spreading sub-lineage (denoted L1A) of porcine reproductive and respiratory syndrome virus (PRRSV) Type 2 from 2014 to 2017. PRRSV is the most important endemic pathogen affecting pigs in the USA, and this particular virulent sub-lineage emerged in 2014 and continues to be the dominant lineage in the US swine industry to date. Data included 984 open reading frame 5 (ORF5) PRRSV L1A sequences obtained from two production systems in a swine-dense production region (∼85,000 mi2) in the USA between 2014 and 2017. The study area was divided into sectors for which model covariates were summarized, and animal movement data between each sector were summarized by age class (wean: 3–4 weeks; feeder: 8–25 weeks; breeding: ≥21 weeks). We implemented a discrete-space phylogeographic generalized linear model using Bayesian evolutionary analysis by sampling trees (BEAST) to infer factors associated with variability in between-sector diffusion rates of PRRSV L1A. We found that between-sector spread was enhanced by the movement of feeder pigs, spatial adjacency of sectors, and farm density in the destination sector. The PRRSV L1A strain was introduced in the study area in early 2013, and genetic diversity and effective population size peaked in 2015 before fluctuating seasonally (peaking during the summer months). Our study underscores the importance of animal movements and shows, for the first time, that the movement of feeder pigs (8–25 weeks old) shaped the spatial patterns of PRRSV spread much more strongly than the movements of other age classes of pigs. The inclusion of movement data into phylodynamic models as done in this analysis may enhance our ability to identify crucial pathways of disease spread that can be targeted to mitigate the spatial spread of infectious human and animal pathogens.

Turnover events of animal caretakers and its impact on productivity in swine farms

Attracting and retaining quality animal caretaking personnel is one of most pressing issues the US swine industry currently faces. On-farm employee turnover can be costly and have an impact on productivity. The primary objectives of this study were to describe the amount of animal caretaker turnover events that occurred in a single year in eleven swine farms, and to investigate associations between employee turnover events and two subsequent production parameters of interest: number of pigs weaned per sow (PWS) and pre-weaning mortality (PWM). A retrospective cohort study was conducted with eleven commercial farrow-to-wean swine farms belonging to two vertically integrated multi-site production systems within two swine production companies. Human resources and production data for the year of 2019 were obtained monthly from each farm. The primary predictor of interest was the occurrence of an employee turnover event, defined as ‘voluntary’ (employee decided to leave or quit) or ‘involuntary’ (employee was terminated by company decision). The primary outcomes of interest included the monthly average PWS and PWM. These associations were assessed with 1-, 2-, 3-, and 6-months between the turnover events and the outcome. Linear mixed effects models were fit in STATA 15, with system and farm included as random effects. To account for temporal and seasonal trends of production, season and the monthly production were included in the models. There were a total of 152 turnover events, with 4 and 148 turnover events in systems 1 and 2, respectively. The average turnover, calculated as a percent of total turnover among full time employee positions, was 92 % (SD = 62 %; Range = 8–217 %). Improved production efficiency in both monthly PWS (p = 0.01) and PWM (p = 0.02) was observed with the occurrence of an involuntary turnover event two months prior, after controlling for season, previous month production, farm, and system. For the PWS outcome, there was a significant interaction between an involuntary turnover event two months prior and monthly county-level unemployment rate (p = 0.02), indicative of the improved performance being most profound at the lowest levels of unemployment rate and diminishing at the highest levels. Turnover of animal caretaking personnel in farrow-to-wean farms was confirmed to be highly variable and high for the majority of farms in this study. Furthermore, animal caretaker turnover was associated with subsequent trends of production efficiency, warranting closer consideration of prioritizing managerial efforts in worker recruitment, training and retention.

79 Direct and Indirect Effects of Heat Stress on the Hepatic and Ovarian Proteome in Gilts

Abstract Seasonal infertility (SI) caused by heat stress (HS) impacts the US swine industry by reducing litter size, farrowing rates, and production efficiency. Identifying the biological underpinnings of SI is a foundational step towards developing mitigation strategies to reduce the nearly $1 billion annual revenue losses to the swine industry. The study objective was to investigate the direct and indirect effects of HS via HS conditioned serum infusion in swine. We hypothesized gilts housed in thermoneutral (TN) conditions receiving gradual infusions of serum obtained from HS gilts would experience altered endocrine and metabolic function compared to gilts receiving serum from TN gilts. Prepubertal gilts (n = 18) were assigned to donor or recipient groups and donors were allocated to TN or HS environments. Blood was collected from HS donors and TN donors exposed to 24-hours of HS or TN conditions, respectively. Serum was infused into recipients housed in TN conditions via indwelling jugular catheters. Over a 24-hour period approximately 20% of the estimated recipient gilt serum volume from donors (pooled by treatment) was infused into recipients. After infusions were completed, gilts were euthanized and tissues collected. Increased rectal temperatures were observed in HS recipients compared to TN recipients (P ≤ 0.05). Protein extracts from liver and ovary underwent proteomic analysis via liquid-chromatography with tandem mass-spectrometry (LC-MS/MS) to assess protein abundance. In the liver and ovary, we identified 135 and 264 proteins, respectively, that were differentially abundant between TN and HS recipients (P < 0.10). Gene Ontology enrichment analysis identified alterations to pathways involved in hormone regulation, immune response, and apoptosis. Collectively, these data demonstrate gilts receiving HS serum experienced altered endocrine and metabolic function compared to gilts receiving TN serum. This project was supported in part by the Iowa Pork Producers Association. USDA is an equal opportunity provider and employer.

305 Awardee Talk: Transferring a culture of biosecurity to the feedmill

Abstract A culture of on-farm biosecurity has been established and practiced by modern swine production systems for many years. The value of this has been repeatedly demonstrated through improved animal health and performance based on the prevention of disease introduction to the herd. With the introduction of Porcine Epidemic Diarrhea Virus (PEDV) to the US swine industry in 2013, we have learned that feed and feed ingredients can be vectors of disease transmission. Therefore, there is a heightened need to transfer our on-farm biosecurity culture to our feedmills and entire feed supply chain as a way to help prevent disease introduction into swine farms. Feedmills are designed to efficiently and effectively blend feed components into a homogenous batch, and the potential to distribute contaminated feed to multiple farms is significant. While feed and ingredients can be vectors of disease and pathogen transmission, our data continues to show that people are a major risk for pathogen transmission throughout the feed supply chain. Key biosecurity principles such as exclusion, prevention, isolation, mitigation, disinfection, and containment should be adopted and enforced for a strong feedmill biosecurity program. A written feedmill biosecurity plan should be developed and a training program that covers all employees as well as visitors and delivery drivers should be implemented. Continuous risk assessment and environmental monitoring should be utilized to identify new areas of risk and to assess the current status. Unfortunately, feedmills are nearly impossible to completely disinfect and therefore every effort should be made to prevent the introduction of pathogens into the mill. Research that we have conducted with PEDV and African Swine Fever Virus has demonstrated that adopting a culture of biosecurity at the feedmill will reduce risk of disease and pathogen exposure on farms.

46 Novel creep area heat source impact on pre-wean mortality occurrence

Abstract Pre-wean mortality (PWM) is a multifaceted problem facing the US swine industry. The objective of this study was to compare the occurrence of mortality and age of piglets between a novel heat source (HS; semi-enclosed heated microclimate; SEHM) and a conventional heat lamp setup. This study was conducted in two rooms at a 1,000 head commercial sow farm. Treatments were blocked by sow parity group (SPG; young, prime, and geriatric) over six farrowing cycles. Litters were cross fostered within HS treatment at 1 day of age. PWM, was the experimental unit, data were collected from the farm’s farrowing records and production accounting system. Age of the mortalities was categorized into four phases of lactation (PL) over the 20 d lactation (d0 to d3, d4 to d7, d8 to d11, and d12 to d20). Overall, there were 220 recorded instances of mortality. Data were analyzed in a CRBD using a PROC MIXED model in SAS (v9.4, SAS Inst., Cary, NC) and reported as LSMEANS with standard errors. The model included farrowing cycle as a random effect and the following fixed effects: HS, SPG, PL, HS*SPG, and HS*PL. Overall average PWM was 8.60%±0.80 for SEHM and 10.0%±0.70 for the heat lamps. There was no effect (P >0.05) of HS or HS*PL on PWM occurrence. There were significant effects of SPG (P=0.026), PL (P=0.05), and HS*SPG (P=0.036) on PWM occurrence. These data suggest that the HS type did not have an impact on the mortality rate or the timing of the mortality, indicating the mortalities that occurred had no relationship to HS. A limitation of this data set is the low sample size, thereby limiting the detection ability for this interaction. Further research into the impact of the HS is needed to expand the data set and to explore other popular HS effects on PWM.

24 Validation of swine enteroids as a model to study Lawsonia intracellularis pathogenesis

Abstract Lawsonia intracellularis is an obligate intracellular bacterium that causes proliferative ileitis, an enteric disease that costs more than $100 million annually to the US swine industry. Information about L. intracellualris pathogenesis is scarce due to lack of suitable in vitro models to study the infection-induced proliferative changes. L. intracellularis infection of the swine ileum has been shown to decrease the number of mucin-producing goblet cells and increase cell proliferation along with amplification of transient amplifying cells demonstrated by the expression of SOX9. The objective of this study was to validate the use of swine enteroids (three dimensional structures derived from adult intestinal stem cells) as a model to study the intestinal epithelial changes caused by L. intracellularis infection. Swine enteroids plated on transwell plate inserts to cover the surface area were infected with 108 L. intracellularis organisms in culture media per well and incubated at 37⁰C with atmospheric conditions of 8.0% oxygen, 8.8% carbon dioxide, and 83.2% nitrogen. Infected enteroids were collected after 7 days and gene expression levels of mucin 2 (MUC2), enterocyte marker fatty acid binding protein (FABP), endocrine marker chromogranin A (CGA), intestinal epithelium marker villin 1 (VIL1), paneth cell marker lysozyme (LYZ), proliferating cell nuclear antigen (PCNA) and SOX9 were measured. The expression of FABP and LYZ in L. intracellularis infected swine enteroids decreased by 50% and 20% respectively and the expression of SOX9 increased by 50%, with no significant changes for the levels of VIL1 and CGA. The changes observed in the infected swine enteroids reflect the profile of gene expression observed in L. intracellularis infected ileal tissue. Therefore, swine enteroids are a suitable in vitro system to study the dynamics of cell differentiation and proliferation of the intestinal epithelium induced by L. intracellularis infection.

The Effects of Sire Line, Slaughter Weight, and Gender on Pork Quality and Yield Characteristics

ObjectivesPork continues to be a significant source of highly valued animal protein for the growing global population. Due primarily to the push for lean yield in the US swine industry, there is a demand from consumers for higher quality pork, while producers continue to desire improved yields. The purpose of this study is to determine the effects of gender and slaughter endpoint on carcass quality and composition attributes for pork from lean yield and meat quality sire lines.Materials and MethodsBoars from a meat quality line (MQL) and a lean yield line (LYL) were mated to females from a commercial swine genetics company. Pigs were farrowed, weaned, and processed according to a typical industry protocol at the University of Georgia Swine research unit. As the pigs reached approximately 23 kg, three pigs from each gender within a litter were selected and randomly assigned a slaughter weight of 113, 136, or 159 kg. When the pigs reached their assigned slaughter weight, they were harvested at The University of Georgia Meat Science and Technology Center under inspection. A total of 151 pigs from 26 litters (13 per sire line) were evaluated. After carcasses were chilled for 24 h, carcass length was measured, and carcasses were then ribbed. Tenth rib back fat (TRBF), last rib back fat (LRBF), loin pHu, carcass muscle score (CMS), NPPC color and marbling scores, Hunter L*a*b*, loin eye area (LEA), and temperature were measured in the longissimus dorsi (LD). Primal and subprimal weights were collected and recorded from the fabricated carcass. Length, width, and depth (thickness) as well as firmness of the skinless belly was assessed. Samples were removed from the LD anterior to the 11thrib for proximate analysis, drip loss, Warner-Bratzler, and slice shear force collection. Data were analyzed using PROC MIXED procedures in SAS with the fixed effects of sire line, gender, and slaughter endpoint and their interactions. LSMEANS were generated and separated using LSD.ResultsBackfat thickness (TRBF and LRBF) was higher in MQL (P < 0.01) than LYL, and lower in females (P < 0.01) than males. The LYL had a greater LEA (P < 0.01) than MQL, and females had a larger LEA (P < 0.01) than males. Marbling and firmness scores (NPPC) were greater in MQL (P < 0.01) than in LYL. As a percent of carcass weight, loin and ham weights were higher for LYL (P < 0.01) than MQL; however, belly weight was greater for MQL (P < 0.01) when compared to LYL. Belly dorsal firmness was greatest in MQL lines with slaughter weight of 159 kg (P < 0.01). Belly dimensions increased (P < 0.01) as slaughter weight increased. Proximate analysis of the LD showed that lipid content was higher (P < 0.01) and moisture content was lower (P < 0.01) in the MQL compared to LYL. Protein levels of the LD were lower from pigs slaughtered at 113 kg (P < 0.01) than both 136 kg and 159 kg. Shear force, by both measurements, was lower in chops from pigs slaughtered at 113 kg (P < 0.01) compared to those slaughtered at 136 and 159 kg. Percent fat free lean was greater (P < 0.01) in LYL, females, and pigs slaughtered at 113 kg compared to MQL, males, and pigs slaughtered at 136 and 159 kg, respectively.ConclusionOverall, there were meat quality advantages for the MQL, but they occurred at the expense of yield, where LYL is superior. Increasing slaughter weights increased primal and subprimal weights and reduced lean yield but had little effect on carcass quality.

Pilot-Scale Assessment of a Novel Farrowing Creep Area Supplementary Heat Source.

Simple SummaryPre-weaning mortality (PWM) causes major economic and productivity losses for the US swine industry. This pilot-scale study evaluated a novel semi-enclosed heated microclimate (SEHM) as a supplementary heat source for farrowing creep areas. Six farrowing cycles (from January to July 2019) were studied in two rooms with 24 farrowing stalls per room. Six SEHMs (each SEHM covers two stalls) were randomly distributed in each room and compared to heat lamps (HLs) for productivity and electricity usage. Data were collected on 113 (SEHM) and 101 litters (HL), and there was no statistically significant difference for average daily gain and weaning weight. There was a tendency for significance of PWM (p = 0.08). A significant difference (p = 0.02) was noted in the PWM attributed to over-lay mortalities, SEHM = 4.05% (± 0.76%) compared to HL = 6.04% (± 0.78%). The SEHM averaged 3.25 kWh d−1 (2.91, 3.59 kWh d−1; 95% CI), which was significantly different (p < 0.01) from the HL equivalent with 125 W bulbs (6 kWh d−1). Based on only electrical savings, payback was estimated at 74 farrowing cycles, or at 12 cycles y−1, 6.1 years. The SEHM demonstrated promising pilot-scale results for increasing productivity and decreasing electricity usage compared to conventional HLs.Pre-weaning morality (PWM) is attributed to a poor creep area microclimate and causes major economic and productivity losses for the US swine industry. Piglets need supplementary heat to overcome a high surface area to body weight ratio and minimal thermoregulation. A pilot-scale study was conducted to evaluate a semi-enclosed heated microclimate (SEHM) as a supplementary heat source for farrowing creep areas over six farrowing cycles (from January to July 2019) in two rooms with 24 farrowing stalls in each room. Six SEHMs (each SEHM covers two stalls) were randomly distributed to each room and compared to heat lamps (HLs) for productivity and electricity usage. Data from 113 (SEHM) and 101 litters (HL) showed no significant difference between treatments in average daily gain (p = 0.26), 252.4 ± 8.0 g hd−1 d−1 (SEHM) and 260.3 ± 8.1 g hd−1 d−1 (HL) and PWM (p = 0.08), 9.67% ± 0.82% (SEHM) and 12.04% ± 0.87% (HL). However, a significant difference (p = 0.02) was noted in the PWM attributed to over-lay mortalities, 4.05% ± 0.76% (SEHM) compared to 6.04% ± 0.78% (HL). The SEHM electricity averaged 3.25 kWh d−1 (2.91, 3.59 kWh d−1; 95% CI), which was significantly different (p < 0.01) from the HL equivalent (125 W bulb; 6 kWh d−1).

Reducing life cycle fossil energy and greenhouse gas emissions for Midwest swine production systems

Abstract Over the last 30 years, the US swine industry has concentrated more animals on fewer farms in the Midwest US corn-belt region to more efficiently produce pork. At the same time, the food industry is beginning to be called upon by consumers to supply products with lower environmental footprints. Swine producers have opportunities to decrease the environmental impacts of their products, but need to know where the most beneficial changes can be incorporated. This study examined the fossil energy consumption and global warming potential (GWP) emissions at Midwestern swine farms using life cycle assessment methodology. Cradle-to-gate swine production scenarios were modeled using a combination of farm productivity survey data and on-farm energy monitoring, with an emphasis on activities related to swine production facilities and their operations. Fossil energy use totaled 10.6 MJ per kg of hog live weight (LW) in the average commercial scenario, 67% of which was used in the grow-finish stage, 11% in the farrowing stage, 12% in the nursery stage, 6% in gestation and 4% in gilt development. Average commercial scenario GWP emissions were 2.41 kg CO2 equiv. per kg hog LW, with 75% emitted during the grow-finish phase, 6% in farrowing, 9% in the nursery phase, 7% in gestation, and 2% in gilt development. Fossil energy required and GWP emissions for facilities and operations were 3.36 MJ and 0.15 kg CO2 per kg hog LW, respectively, and accounted for 32% of the system fossil energy and 6% of emissions in the average commercial scenario. Though fossil energy and GWP impacts resulting from swine production facilities and operations are smaller than those for feed ingredients and manure management, swine producers can directly influence these impacts through management. Heating, cooling, and ventilation are prime areas in facilities and operations where energy efficiency technology could reduce impacts. Lowering facility and operation energy inputs by 30% would decrease fossil fuel use in the system by 10% and slightly decrease GWP emissions. In the future, substituting renewable energy for fossil-based energy and using other efficiency technologies for current electricity and heating fuel needs may be able to eliminate the fossil energy needed for swine facilities and production operations.

Macroepidemiological aspects of porcine reproductive and respiratory syndrome virus detection by major United States veterinary diagnostic laboratories over time, age group, and specimen.

This project investigates the macroepidemiological aspects of porcine reproductive and respiratory syndrome virus (PRRSV) RNA detection by veterinary diagnostic laboratories (VDLs) for the period 2007 through 2018. Standardized submission data and PRRSV real-time reverse-transcriptase polymerase chain reaction (RT-qPCR) test results from porcine samples were retrieved from four VDLs representing 95% of all swine samples tested in NAHLN laboratories in the US. Anonymized data were retrieved and organized at the case level using SAS (SAS® Version 9.4, SAS® Institute, Inc., Cary, NC) with the use of PROC DATA, PROC MERGE, and PROC SQL scripts. The final aggregated and anonymized dataset comprised of 547,873 unique cases was uploaded to Power Business Intelligence—Power BI® (Microsoft Corporation, Redmond, Washington) to construct dynamic charts. The number of cases tested for PRRSV doubled from 2010 to 2018, with that increase mainly driven by samples typically used for monitoring purposes rather than diagnosis of disease. Apparent seasonal trends for the frequency of PRRSV detection were consistently observed with a higher percentage of positive cases occurring during fall or winter months and lower during summer months, perhaps due to increased testing associated with well-known seasonal occurrence of swine respiratory disease. PRRSV type 2, also known as North American genotype, accounted for 94.76% of all positive cases and was distributed across the US. PRRSV type 1, also known as European genotype, was geographically restricted and accounted for 2.15% of all positive cases. Co-detection of both strains accounted for 3.09% of the positive cases. Both oral fluid and processing fluid samples, had a rapid increase in the number of submissions soon after they were described in 2008 and 2017, respectively, suggesting rapid adoption of these specimens by the US swine industry for PRRSV monitoring in swine populations. As part of this project, a bio-informatics tool defined as Swine Disease Reporting System (SDRS) was developed. This tool has real-time capability to inform the US swine industry on the macroepidemiological aspects of PRRSV detection, and is easily adaptable for other analytes relevant to the swine industry.