DOI: 10.5061/dryad.76hdr7t55
title: Rearing pigs with play opportunities: viral load and clinical, behavioural, performance, and immune data

description: Positive emotions can reduce disease susceptibility during
 infectious challenges in humans, and emerging evidence suggests
 similar effects in farm animals. Because play behaviour may
 support a positive emotional state in pigs, this study
 investigates whether rearing pigs with regular intermittent play
 opportunities enhances disease resilience when challenged with
 porcine reproductive and respiratory syndrome virus (PRRSV).
 Litters were assigned to either play (PLY; n = 5 L) or control
 (CON; n = 4 L) treatments at birth. In PLY, play was promoted
 with extra space and enrichment items for three hours daily from
 five days of age (doa). At weaning (25 ± 2 doa; mean ± SD), 28 pigs
 (14/treatment) were selected for a disease challenge, based on weight,
 sex, and sow. The pigs were transported to a disease containment
 facility and at 43 ± 2 doa (day 0 post-inoculation, DPI)
 inoculated with PRRSV. Skin lesions, blood, rectal temperature,
 clinical signs, body weight, and behaviour were collected pre-
 and post-inoculation. Play opportunities for PLY continued every other
 day until euthanasia of all pigs at 65 ± 2 doa (22 DPI). PLY pigs
 exhibited fewer skin lesions following transport and throughout
 the infection compared to CON. Although the viral load did not
 differ between treatments, PLY pigs had a lower probability of
 experiencing moderate and severe respiratory distress, with
 a shorter duration. PLY also performed better throughout the
 infection, showing higher ADG and greater feed efficiency. The
 immune response differed as well. PLY pigs had fewer monocytes on
 8 DPI than CON, with levels returning to baseline by 21 DPI,
 whereas CON levels exceeded baseline. Regardless of day of infection,
 lymphocyte counts tended to be lower in PLY than in CON, and white blood
 cells and neutrophils were also lower, but only in slow-growing pigs. PLY
 pigs continued to play during the infection, demonstrating less
 sickness behaviour and emphasizing the rewarding properties of
 play. Results suggest that PLY pigs were less affected by PRRSV
 and developed increased resilience to PRRSV compared to CON.
 This study demonstrates that rearing pigs in an environment
 supporting positive experiences through provision of play
 opportunities can enhance resilience against common modern
 production challenges, underscoring the value of positive welfare
 in intensive pig farming.
description: Animal measures in detail, including tables, are described in the
 published paper. Citation: Steinerová K, Harding JC,
 Parker SE, Wilson HL, Nery Finatto A and Seddon YM (2024) Rearing pigs
 with play opportunities: the effects on disease resilience in pigs
 experimentally inoculated with PRRSV. Front. Vet. Sci. 11:1460993. doi:
 10.3389/fvets.2024.1460993 <strong>Behaviour and
 skin lesions</strong> The duration of play
 (locomotor, social and object) and exploratory behaviour (Table 2) were
 scored with continuous sampling within the initial 10 min of the play
 sessions only in the PLY treatment at -2 (baseline), 3, 7, 11, 16 and 20
 DPI. The scoring commenced after an experimenter exited the playpen and
 closed the gate. On the same days, to assess pig activity during the
 challenge, the frequency of active, inactive, and feeding behaviours
 (Table 2) in the PLY and CON treatments were assessed through
 instantaneous sampling within the first half of the play sessions at 5-min
 intervals (90 min, 18 scans/pig/DPI). Additionally, scans were collected
 at 10-min intervals when no play sessions were occurring for two 90-min
 periods without human presence in the pen, in the morning (between 7:30 –
 9:30 AM) and evening (between 5:00 – 7:00 PM), totalling 180 min per day
 (18 scans/pig/DPI). In the chosen periods, human presence in the BSL2 was
 recorded only in the AM, and when it happened, an experimenter continued
 scanning but noted a person in the room. The pigs were individually marked
 with spray paint (Raidex GmbH, Dettingen/Erms, Germany) at least two hours
 before video recording. All behaviours were videotaped
 with Lorex cameras (4K Ultra HD IP Security Camera, Lorex Technology,
 Markham, ON, Canada) in the farrowing room (one camera/two neighbouring
 home pens), the nursery room (one camera/home pen, one camera/two
 playpens) and the BSL2 room (one camera/pen; Figure 1). The behaviours
 were scored from the video recordings by one experimenter using the
 Observer software XT14 (version 14.2.1127, Noldus, Leesburg, VA, USA). The
 experimenter could not be blinded to the treatments due to clear
 distinctions between treatments in the experimental set up (playpens in
 PLY) and restricted number of trained personnel allowed to access to the
 disease containment facility. Skin lesions were scored
 as a proxy measure of aggression (Turner et al., 2006) two days
 pre-weaning (age: D23 ± 2 (days); mean ± S.D.), one-day post-weaning (age:
 D26 ± 2), one day before transport (age: D33 ± 2), one day after transport
 (age: D35 ± 2), pre-inoculation (-2 DPI, age: D40 ± 2) and at the end of
 the trial (21 DPI, age: D64 ± 2). The body was divided into six regions:
 ears, face, front (neck, shoulders, and front legs), middle (the body
 after the shoulders up to the frontal tip of the hind legs), rear (the
 hind legs), and tail[1]
 (modified from Turner et al., 2006). Each body region was scored
 individually and was assigned a score from 0 to 3: score 0 (none) = no
 lesions; score 1 (mild) = less than five superficial scratches; score 2
 (moderate) = 5-10 superficial scratches and/or less than three deep
 wounds; score 3 (severe) = more than 10 superficial scratches and/or more
 than three deep wounds. A total body skin lesion score was calculated by
 summing all body region scores per pig and day (maximum score of
 18/pig/day). One experimenter, who could not be blinded to the treatments,
 directly scored the skin lesions while standing outside the pen.
 <strong>Rectal temperature and body
 weight</strong> Rectal temperature (RT) was taken
 on 0 (baseline), 2, 4, 8, 13, 17, and 21 DPI using a digital thermometer
 with a flexible tip and a resolution of 0.1ºC. On 0 DPI, a baseline RT was
 measured pre-inoculation. However, due to technical difficulties with the
 thermometer, the initial baseline data were discarded, and the baseline RT
 was recorded three hours post-inoculation before the onset of detectable
 viremia (6-48 hours post-exposure; Zimmerman et al., 2019a) using a new
 thermometer that was used thereafter. The pigs were weighted on 0, 8, 13,
 17, and 21 DPI on a digital scale with a resolution of 0.1 kg. The ADG
 post-inoculation was calculated between each subsequent weigh period per
 pig. <strong>Blood collection and clinical
 signs</strong> Blood (serum, EDTA) was collected
 from the jugular vein with the pig restrained in a supine position on -1,
 2, 4, 8, 13, 17, and 21 DPI. Tubes with EDTA were gently inverted 8-10
 times to ensure thorough mixing with the anti-coagulant and stored on ice.
 Rectal temperature, body weight, and blood were collected between 8 to 10
 am in the aforementioned order. To prevent
 cross-contamination, the negative control pigs in the BSL1 were blood
 sampled (serum, EDTA), and weighted and their RT was collected on -1
 (blood) or 0 (weight, RT), 13, and 21 DPI before the pigs in the
 BSL2. The pigs in the BSL2 were monitored for PRRSV
 clinical signs with scores assigned based on severity (0: not present, 4:
 severe) in the AM and PM. The negative control pigs in the BSL1 were
 monitored in the AM only by a separate team, from the first day in the
 acclimation period until 21 DPI. Monitored clinical signs included:
 respiratory distress (RD), coughing, responsiveness, appetite, colour of
 the skin, consistency of the faeces, body condition, and additionally
 lameness as a clinical sign not specific to PRRSV (see description in
 Table 2 in the suppl. mat.). <strong>Pen feed
 intake</strong> Pen feed intake was recorded in
 the PM pre-inoculation on -8, -5, and -1 DPI, and post-inoculation on 2,
 6, 9, 13, 16, 20, and 21 DPI. Feed intake was divided into periods:
 pre-inoculation (DPI -8 to -1; 8 days), one-week post-inoculation (DPI 0
 to 6; 7 days), second-week post-inoculation (DPI 7 to 13; 7 days),
 third-week post-inoculation (DPI 14 to 21; 8 days), from which the average
 feed intake per pig per day in a given period was calculated. Feed-to-gain
 ratio (F:G) was calculated per pen (total (from 0 to 21 DPI) feed intake
 per pen / total gain per pen) and averaged per treatment.
 <strong>Gross lung lesions</strong>
 At necropsy, lungs were rinsed with water and carefully placed on
 a tray, and their ventral and dorsal surface showing left and right
 cranial (CR), middle (M), caudal (CA), and accessory (A) lobes were
 photographed for later examination of pathomorphological changes. A
 consistent observer utilized a lung drawing from Halbur et al. (1995) to
 shade areas on the lobes exhibiting the colour change observed in the
 photographs. Lung lesions typical of interstitial pneumonia and differing
 in severity with colour ranging from tan to dark red and purple (Zimmerman
 et al., 2019b) were identified. A 9 mm by 9 mm grid was placed on the
 shaded lung drawing to calculate the proportion of the affected lobes
 (number of shaded grid squares (with a precision of ¾ of a square) / total
 number of grid squares). This proportion was then multiplied with a
 pre-defined score assigned to each lobe (ventral left and right – CR: 10,
 M: 10, CA: 25, A: 5; dorsal left and right – CR: 10, M: 10, CA: 30; Halbur
 et al. 1995), resulting in an estimate of the percentage of the affected
 lobe, and thereafter summed to determine the total affected area of the
 lungs. Other characteristics of the gross lung lesions, such as the
 consistency of the lungs (slightly firm to rubbery) (Zimmerman et al.,
 2019b) were not possible to record from the photographs.
 <strong>Lab analyses</strong>
 Immediately after the blood collection, whole blood (-1, 2, 4, 8,
 13, 17, and 21 DPI) was submitted to Prairie Diagnostic Services (PDS) for
 a total count of white blood cells (WBC) and differential counts of
 lymphocytes, neutrophils, and monocytes counted in a haematology analyser
 (Advia 2120i, Siemens Healthcare Diagnostics, Erlangen, Germany). Serum
 was extracted from serum-separating tubes
 (Vacutainer<sup>®</sup> SST<sup>™</sup>) by
 centrifuging 1500 <em>g</em> for 10 min at 4°C, aliquoted to
 vials and stored at -80°C until further analysis. Serum samples (-1, 2, 4,
 8, 13, 17, and 21 DPI) were analysed for total circulating
 triiodothyronine (T3), and PRRSV RNA. Triiodothyronine was quantified in
 PDS in the IMMULITE® 2000 Systems Analyser (Siemens Healthcare
 Diagnostics, Erlangen, Germany). The samples were assayed in duplicate
 with a calibration range of 0.61 to 9.2 nmol/L and analytical sensitivity
 of 0.29 nmol/L, with the protocol followed without any
 modifications. <strong>Quantification of PRRSV
 RNA</strong> The concentration of PRRSV strain
 NVSL 97-7895 RNA was determined using an in-house quantitative reverse
 transcription PCR assay (qRT-PCR). Each sample was individually assessed
 for the presence of target PRRSV RNA copies/mL. RNA was extracted from 140
 µL of serum using the QIAamp Viral RNA mini kit (Qiagen Inc., Toronto, ON)
 according to the manufacturer’s instructions. The concentration (A260) and
 purity (A260/A280) of the extracted viral RNA were determined using
 spectrophotometry (NanoDrop 2000c, Thermo Fisher Scientific).
 To quantify PRRSV RNA levels in the serum of pigs, a probe-based
 qRT-PCR assay previously described by Ladinig et al., (2014) was employed.
 The primers and probe targeted the highly conserved region at the
 C-terminal end of ORF7 of NVSL 97-7895. The primer sequences were as
 follows: PRRS-2F primer 5’-TAA TGG GCT GGC ATT CCT-3’, PRRS-1R primer
 5’-ACA CGG TCG CCC TAA TTG-3’, and the probe 5’-HEX-TGT GGT GAA TGG CAC
 TGA TTG RCA-BHQ2-3’. A dilution series (1.8 x 108 to 1.8 x 102 copies/µL)
 of HindIII linearized plasmid, pCR2.1TOPO-NVSL, containing a 446 bp
 sequence of ORF7, was used as a standard curve. The standards were run in
 triplicate on each PCR plate, while the tested samples were run in
 duplicate. All qRT-PCR reactions were performed on a 96-well plate
 (Hard-Shell 96-Well PCR Plate, Applied Biosystems), sealed with a
 Microseal ‘B’ PCR Plate Sealing Film (Applied Biosystems), and analysed on
 a Step-One Plus Real-Time PCR System (Bio-Rad Laboratories). Each qRT-PCR
 reaction consisted of 2 µL of sample or standard, 6 µL of RNAse-free
 water, 10 µL of iTaq Universal Probes 1-step kit (Bio-Rad Laboratories),
 10 µM of PRRS-2F primer, 10 µM of PRRS-1R primer, 10 µM of PRRS-P1 probe,
 and 0.5 µL of iScript reverse transcriptase (Bio-Rad Laboratories). The
 thermocycling protocol included a reverse transcription step at 50°C for
 30 min, followed by an initial activation step at 95°C for 10 min, and 40
 cycles of denaturation (30 sec at 95°C) and annealing/extension (30 sec at
 59°C). Individual samples were re-run if the cycle quantification (Cq)
 standard deviation between duplicates was &gt;1.0 or if one of the
 duplicates had no cycle threshold (Ct) value. The results were reported as
 PRRSV RNA concentration per mL of serum. The limits of quantification were
 determined based on the least and most concentrated standards. Samples
 were considered negative if the target RNA was not detected or DNQ
 (detected, but not quantifiable).
description: # Rearing pigs with play opportunities: viral load and clinical,
 behavioural, performance, and immune data
 [https://doi.org/10.5061/dryad.76hdr7t55](https://doi.org/10.5061/dryad.76hdr7t55) ## Description of the data and file structure This study is a part of a PhD in Swine behaviour and welfare at the University of Saskatchewan. This PhD focusses on improvement of the quality of life of farmed pigs in intensive production on Canadian farms using affordable and practical approaches. It is investigated if play behaviour can be used as a tool to improve resilience and robustness of farmed pigs. This study used disease challenge in pigs reared with play and explored whether pigs reared with play exhibit greater disease resilience. For methodology on how play was promoted and description of pig treatments, see the published paper. Because play behaviour may support a positive emotional state in pigs, this study investigates whether rearing pigs with regular intermittent play opportunities enhances disease resilience when challenged with porcine reproductive and respiratory syndrome virus (PRRSV). Skin lesions, blood, rectal temperature, clinical signs, body weight, and behaviour were collected pre- and post-inoculation with PRRSV. All datasets provided are in Microsoft Excel and include the exact variables that were used for statistical analysis. For details about the analysis, please, read the published paper. Abbreviations of variables are denoted in the relevant dataset. ### Files and variables Rearing pigs with pig opportunities: viral load and clinical, behavioural, performance, and immune data: data used for statistical analysis. All datasets contain the following variables describing the experimental unit, the pig: * Pigid: individual number (id) of each pig * Trt (+ trt_code): treatment; CON (control), PLY (play), sentinel * Pen (+ pen_code): pen number where the pig was housed * Sow (+ sow_code): sow number, origin of the pig * Sex (+ sex_code): gender of the pig, f (female/gilt), m (male/barrow) * Dpi: day post-inoculation * d3wg: birth weight of the pig taken on day 3 after farrowing, unit kilogram (kg) * dpi0wg: weight of the pig on day post-inoculation 0 (0 DPI) taken before the inoculation took place, unit kilogram (kg) * adgd3d26: average daily gain (ADG) pre-weaning, calculated from birth weight and day 26 weight, unit kilogram (kg) * adgd3dpi0: average daily gain (ADG) calculated from birth weight and weight of the pig on day post-inoculation 0 (0 DPI) taken before the inoculation took place, unit kilogram (kg) Other important information: * Cells with unavailable and missing information (e.g., sample lost, or pig died) are coded with “null”. * Cells with information that is not applicable to the specific cell (e.g., pig deliberately not measured, equipment not used) are coded as "na" (not applicable). * Binary variable yes/no is coded: yes=1, no=0. * Negative control pigs (not inoculated pigs) are coded as sentinel. #### File: PRRSV\_Play\_study\_Clinical\_signs\_\_rectal\_temperature\_and\_medical\_treatments.xlsx **Description:** Post-inoculation with PRRSV: Clinical signs and their duration in days and probability to occur, rectal temperature and medical treatments. Excel file has multiple tabs with additional variables. The full name of the variables is given first, followed by the abbreviation in brackets, and full description. **Tab name: Clinical signs number of days** The layout of the tab: row 1 gives full name of the variables, row 2 gives abbreviations of the variables Variables: * \# days of respiratory rate &gt;0 (1-4), (drate0): number of days the pig spent experiencing respiratory rate between score 1 to 4; * \# days of respiratory rate &gt;1 (1.5-4), (drate1): number of days the pig spent experiencing respiratory rate between score 1.5 to 4; * \# days of respiratory rate &gt;1.5 (2-4), (drate15): number of days the pig spent experiencing respiratory rate between score 2 to 4; * \# days of respiratory rate &gt;2 (3-4), (drate2): number of days the pig spent experiencing respiratory rate between score 3 to 4; * \# of days responsiveness &gt;0 (1-3), (dresp0): number of days the pig spent experiencing responsiveness between score 1 to 3; * \# of days responsiveness &gt;1 (2-3), (dresp1): number of days the pig spent experiencing responsiveness between score 1 to 3 **Tab name: Clinical signs probability** The layout of the tab: row 1 gives full name of the variables, row 2 gives abbreviations of the variables Variables: * Responsiveness score (resp): the pig scored this score; * Responsiveness &gt;=1 (resp&gt;=1): score more or equal to 1 (yes/no); * Responsiveness &gt;=2 (resp&gt;=2): score more or equal to 2 (yes/no); * Responsiveness probability of being 1 (respprob1): probability of the pig to experience this score (yes/no); * Responsiveness probability of being 2 (respprob2): probability of the pig to experience this score (yes/no); * Skin colour score (skincol): the pig scored this score; * Skin colour &gt;=1 (skincol&gt;=1): score more or equal to 1 (yes/no); * Skin colour &gt;=2 (skincol &gt;=2): score more or equal to 2 (yes/no); * Skin colour probability of being 1 (skincolprob1): probability of the pig to experience this score (yes/no); * Skin colour probability of being 2 (skincolprob2): probability of the pig to experience this score (yes/no); * Coughing score (cough): the pig scored this score; * Coughing &gt;=1 (cough&gt;=1): score more or equal to 1 (yes/no); * Coughing &gt;=2 (cough&gt;=2): score more or equal to 2 (yes/no); * Coughing probability of being 1 (coughprob1): probability of the pig to experience this score (yes/no); * Coughing probability of being 2 (coughprob2): probability of the pig to experience this score (yes/no); * Respiratory Rate score (rrate): the pig scored this score; * Respiratory Rate &gt;=1 (rrate&gt;=1): score more or equal to 1 (yes/no); * Respiratory Rate &gt;=1.5 (rrate&gt;=1.5): score more or equal to 1.5 (yes/no); * Respiratory Rate &gt;=2 (rrate&gt;=2): score more or equal to 2 (yes/no); * Respiratory Rate &gt;=2.5 (rrate&gt;=2.5): score more or equal to 2.5 (yes/no); * Respiratory rate probability of being 1 (rrateprob1): probability of the pig to experience this score (yes/no); * Respiratory rate probability of being 1.5 (rrateprob15): probability of the pig to experience this score (yes/no); * Respiratory rate probability of being 2 (rrateprob2): probability of the pig to experience this score (yes/no); * Respiratory rate probability of being 2.5 (rrateprob25): probability of the pig to experience this score (yes/no); * Body Condition score (bc): the pig scored this score; * Body Condition&gt;=1 (bc&gt;=1): score more or equal to 1 (yes/no); * Lameness score (lam): the pig scored this score; * Consistency of the feces score (feces): the pig scored this score; * Appetite score (appet): the pig scored this score; * Treated with meloxicam (mel, +mel_code): the pig treated (yes/no); * Treated with excenel (exc, +exc_code): the pig treated (yes/no) **Tab name: Clinical signs scores described** Variables: * Health observation: name of clinical signs; * score: score given; * clinical signs: description of the clinical sign. **Tab name: Rectal temperature** The layout of the tab: row 1 gives full name of the variables, row 2 gives abbreviations of the variables Variables: * Final rectal temperature (units: °C), (temp): the rectal temperature of the pig in degrees Celsius; * Temp Braun (setting 0-3) only used for negative control pigs after 0 DPI, (tempbraun): the rectal temperature and thermometer used for negative control pigs; * Treated with meloxicam (mel, +mel_code): treated yes/no; * Treated with excenel (exc, +exc_code): treated yes/no. **Tab name: medical treatments yesno** Variables: * treated(y/n): treated yes (y)/no (n); * treated_code: code for yes (1)/no (0). **Tab name: medical treatments – detailed** Variables: * date: date of treatment; * time: time of treatment; * medical treatment: name of the medical treatment and its dosage in mL; * medtrt_code: code for the medical treatment (1=meloxicam, 2=excenel); * day of treatment: day of treatment; * rectal temperature: rectal temperature the pig measured at the time of treatment. #### File: PRRSV\_Play\_study\_Immune\_cells\_and\_T3.xlsx **Description:** Post-inoculation with PRRSV: Immune cells determined from blood sampling, and triiodothyronine(T3) from serum. The full name of the variables is given first, followed by the abbreviation in brackets, and full description. **Tab name: T3 WBC final** The layout of the tab: rows 1 and 2 give reference interval x 10^9/L for variables below, row 3 gives full name of the variables, row 4 gives abbreviations of the variables. Variables: * T3 (nmol/L), (t3): laboratory results of triiodothyronine (T3) with units (nmol/L); * T3 (nmol/L) &lt;0.62 coded 0.3, (t3_code3): laboratory result from of the triiodothyronine (T3) with units (nmol/L) with levels under 0.62 coded as 0.3; * WBC, (wbc): laboratory results of white blood cells (WBC), unit 10^9/L; * WBC Out of range lower (1) higher (2), (wbcoor): white blood cells out of range, 1 lower, 2 higher than the range; * Segmented neutrophils (seg): laboratory results of neutrophils, unit 10^9/L; * Segmented neutrophils relative %, (seg%): relative percentage of neutrophils from the total count of wbc; * Segmented neutrophils Out of range lower (1) higher (2) (segoor): neutrophils out of range, 1 lower, 2 higher than the range; * Lymphocytes, (lym): laboratory results of lymphocytes, unit 10^9/L; * Lymphocytes relative %, (lym%): relative percentage of lymphocytes from the total count of wbc; * Lymphocytes Out of range lower (1) higher (2), (lymoor): lymphocytes out of range, 1 lower, 2 higher than the range; * Monocytes (mon): laboratory results of monocytes, unit 10^9/L; * Monocytes relative %, (mon%): relative percentage of monocytes from the total count of wbc; * Monocytes Out of range  lower (1) higher (2), (monoor): out of range, 1 lower, 2 higher than the range. #### File: PRRSV\_Play\_study\_Skin\_lesion\_scores.xlsx **Description:** Post-inoculation with PRRSV: Skin lesions score as proxy of aggression between pigs. Excel file has multiple tabs with additional variables. **Tab name: Skin lesions long format** Variables:   * day: experimental day; * lesions ears, (ears): the score the pig was given for the body region; * lesions face, (face): the score the pig was given for the body region; * lesions neck, shoulders, front legs, (front): the score the pig was given for the body region; * lesions middle, (mid): the score the pig was given for the body region; * lesions hind legs, bum, (hind): the score the pig was given for the body region; * lesions tail, (tail): the score the pig was given for the body region; * total lesion score (max 18): the total lesion score, all regions summed together. **Tab name: scoring criteria** This tab provides information about the scoring criteria. #### File: PRRSV\_Play\_study\_Preweaning\_piglet\_and\_sow\_info\_\_\_prewean\_average\_daily\_gain.xlsx **Description:** Piglet and sow information from preweaning period. Excel file has multiple tabs with additional variables. **Tab name: Preweaning info** This tab provides information about piglets selected for the disease trial. Variables show the descriptive information about piglets. Variables: * from Sow: from which sow the pig comes from; * Litter notch ID: identification notch of the litter; * Born: date born; * Weight D3 of age (kg): birth weight (kg); * Weight exp. D26 (kg): weight on day 26; * Frequency of total play D21: frequency of total play the pig played on day 21; * Treatment: control, play or sentinel treatment, where the pig belongs; * Farrowing Pen: original farrowing pen to which the pig was born to; * Piglet notch ID: piglet notch identification; * Pig tag ID: pig tag ID given by experimenter, from now on only pigID; * Pen group: pen group for disease challenge The remaining variables describe the ages of the pigs on various days: * Age (days) at weaning (D28); * Age (days) at transport (D37); * Age (days) at inoculation (D45); * Age (days) at euthanasia (D67). The calculation is in the cell and the final results is in row 2 as mean and standard deviation of the mean. **Tab name: Sow farrowing info** This tab provides information about the sows. Variables show the descriptive information about sows. Variables: * Parity: the number of parity the sow is at; * Sow Genetics: genetic line of the sow; * Pen; * Farrowing date: date when the sow farrowed; * Litter id: identification of the litter; * Born alive: number of piglets born alive; * Stillborn: number of stillborn; * Mummified: number of mummified piglets #### File: PRRSV\_Play\_study\_Viral\_load\_RNA.xlsx **Description:** Post-inoculation with PRRSV: Viral load: concentration of PRRSV RNA detected in qPCR and isolated from serum.  Excel file has multiple tabs with additional variables. **Tab name: long stata final log10** Variables: * SQ mean (1ml): laboratory results from quantitative polymerase chain reaction (qPCR) standard quantity (SQ) mean per 1mL; * log10rna/ml: transformed values into logarithms 10 of the target virus (PRRSV) RNA per 1mL. Note: for dpi-1 for all pigs and dpi21 for pig 15 and pig 30: Logarithm of 0 to the base 10 (log10 0) is coded undefined but is coded as 0 for statistical purposes. **Tab name: log10 calc** This tab provides calculations from the standard quantity into the logarithms 10 for each pig and day post-inoculation. The formulas are in the cell. Variables: * dpi2_sq1ml: the standard quantity per 1 mL measured on 2 DPI; * dpi2_log10_sq1ml: the logarithms 10 of the standard quantity per 1 mL measured on 2 DPI, formula in the cell; * same for all subsequent days. Note: for dpi-1 for all pigs and dpi21 for pig 15 and pig 30: Logarithm of 0 to the base 10 (log10 0) is coded as undefined. **Tab name: AUC** Variable: auc: area under the curve calculated over time per pig from the statistical software #### File: PRRSV\_Play\_study\_Play\_\_exploratory\_\_active\_\_inactive\_\_feeding\_behaviours.xlsx **Description:** Post-inoculation with PRRSV: Pig behaviours collected with continuous and scan sampling. Excel file has multiple tabs with additional variables. The full name of the variables is given first, followed by the abbreviation in brackets, and full description. The layout of the tab: row 1 gives full name of the variables, row 2 gives abbreviations of the variables **Tab name: Play and exploratory behaviours** Variables: * Duration (second) of total play (loc, soc, obj combined), (durplay): Duration (second) of total play (locomotor, social object play combined); * Duration (sec) of locomotor play, (durloc): Duration (seconds) of locomotor play; * Duration (sec) of object play, (durobj): Duration (seconds) of object play; * Duration (sec) of social playm (dursoc): Duration (seconds) of social play; * Duration (sec) of exploratory behaviour, (durexp): Duration (seconds) of exploratory behaviour; * Duration (sec) of other behaviours, (durother): Duration (seconds) of other behaviours, for definition of other behaviours, see the published paper; * Duration (sec) observed (exposure), (durobserved): Duration (seconds) the pig was observed used as exposure for statistical analysis. **Tab name: Active Inactive Feeding behave** * Play behaviour AM, (play_am): scans of the behaviour per pig recorded in the AM * Play behaviour PM, (play_pm): scans of the behaviour per pig recorded in the PM * Exploratory behaviour AM, (expl_am): scans of the behaviour per pig recorded in the AM * Exploratory behaviour PM, (expl_pm): scans of the behaviour per pig recorded in the PM * Walking AM, (walk_am): scans of the behaviour per pig recorded in the AM * Walking PM, (walk_pm): scans of the behaviour per pig recorded in the PM * Standing AM, (stand_am): scans of the behaviour per pig recorded in the AM * Standing PM, (stand_pm): scans of the behaviour per pig recorded in the PM * Sitting AM, (sit_am): scans of the behaviour per pig recorded in the AM * Sitting PM, (sit_pm): scans of the behaviour per pig recorded in the PM * Feeding behaviour AMPM disturbance, (feed_ampmdist): scans of the behaviour per pig recorded in the AM and PM, included when the pigs were disturbed * Drinking AM, (drink_am): scans of the behaviour per pig recorded in the AM * Drinking PM, (drink_pm): scans of the behaviour per pig recorded in the PM * Active lying AM, (lieact_am): scans of the behaviour per pig recorded in the AM * Active lying PM, (lieact_pm): scans of the behaviour per pig recorded in the PM * Sleeping AM, (sleep_am): scans of the behaviour per pig recorded in the AM * Sleeping PM, (sleep_pm): scans of the behaviour per pig recorded in the PM * Active behaviour AM, (active_am): scans of the behaviours per pig recorded in the AM, see the publication for description what includes active behaviour * Active behaviour PM, (active_pm): scans of the behaviours per pig recorded in the PM, see the publication for description what includes active behaviour * Inactive behaviour AM, (inactive_am): scans of the behaviours per pig recorded in the AM, see the publication for description what includes inactive behaviour * Inactive behaviour PM, (inactive_pm): scans of the behaviours per pig recorded in the PM, see the publication for description what includes inactive behaviour * Feeding AMPM with disturbance, (feeding_ampmdist): scans of the behaviour per pig recorded in the AM and PM, including when the pigs were disturbed * Exposure feeding disturbance, (exposure_feeddist): the total number of scans the pigs were observed and scored feeding in the AM and PM, used as exposure for statistical analysis * Exposure AM, (exp_am): the total number of scans the pigs were observed and scored performing active or inactive behaviours in the AM, used as exposure for statistical analysis * Exposure PM, (exp_pm): the total number of scans the pigs were observed and scored performing active or inactive behaviours in the PM, used as exposure for statistical analysis #### File: PRRSV\_Play\_study\_Lung\_lesions.xlsx **Description:** Post-inoculation with PRRSV: Gross lung lesions collected at pig necropsy. The full name of the variables is given first, followed by the abbreviation in brackets, and full description. **Tab name: Lung lesions final result** The layout of the tab: row 1 gives full name of the variables, row 2 gives abbreviations of the variables. Variables: * left dorsal points (max 25), (ld_points): the number of points (maximum 25) the pig scored on the left dorsal lung area; * ld_comment: any relevant comments aiding the scoring; * right dorsal points (max 25), (rd_points): the number of points (maximum 25) the pig scored on the right dorsal lung area; * rd_comment: any relevant comments aiding the scoring; * left ventral points (max 22.5), (lv_points): the number of points (maximum 22.5) the pig scored on the left ventral lung area; * lv_comments: any relevant comments aiding the scoring; * right ventral points (max 22.5), (rv_points): the number of points (maximum 22.5) the pig scored on the right ventral lung area; * rv_comment: any relevant comments aiding the scoring; * middle lobe ventral (max 5), mv_points: the number of points (maximum 5) the pig scored on the middle lobe lung area; * mv_comment: any relevant comments aiding the scoring; * mottled areas (no 0, yes 1), (mottled): mottled lung, 1=yes, 0=no; * colour (pink 0, purple 1), (colour): what colour of the lung, 0=pink, 1=purple; * % lungs affected, (totalpoints): the total percentage the pig scored for the entire lungs; * % dotted areas, (totaldots): the total number of dotted area the pig had on the lungs. #### File: PRRSV\_Play\_study\_Post-inoculation\_average\_daily\_gain\_\_feed\_intake\_\_feed\_to\_gain.xlsx **Description:** Post-inoculation with PRRSV: Performance of pigs: gain, feed intake, feed efficiency. Excel file has multiple tabs with additional variables. The full name of the variables is given first, followed by the abbreviation in brackets, and full description. **Tab name: ADG post-inoc final results** Variables: ADG: average daily gain (kg) calculated per pig per days post-inoculation (DPI) period **Tab name: ADG post-inoc calculation** The layout of the tab: row 1 gives information to which pigs are considered in the calculation, row 2 gives information to which DPI periods are considered in the calculation, row 3 shows the name of the variables Variables: * Weight (kg): weight of the pig on the particular DPI; * ADG_0: calculation of the average daily gain (kg) per inoculated pig from 0 DPI to 21 DPI, formula in the cell; * ADG_1: calculation of the average daily gain (kg) per inoculated pig for DPI period 1, formula in the cell; * ADG_2: calculation of the average daily gain (kg) per inoculated pig for DPI period 2, formula in the cell; * ADG_3: calculation of the average daily gain (kg) per inoculated pig for DPI period 3, formula in the cell; * ADG_4: calculation of the average daily gain (kg) per inoculated pig for DPI period 4, formula in the cell; * ADG_1a: calculation of the average daily gain (kg) per negative control (sentinel) pig 1a for DPI periods, formula in the cell; * ADG_2a: calculation of the average daily gain (kg) per negative control (sentinel) pig 2a for DPI periods, formula in the cell. **Tab name: Feedgain_feed intake** This tab provides calculation of the total feed intake per pen used for the calculation of gain to feed ratio. Variables: * pigs: number of pigs; * period: period number; * days: days in the period; * Total consumption/period: Total consumption per period (kg); * pen: pen for which the feed intake is calculated; * total feed intake (kg)/pen: total feed intake (kg) per pen, formula in the cell. **Tab name: Feedgain_Pig weight** This tab provides calculation of the total gain per pen used for the calculation of gain to feed ratio. Variables: * Total gain/pig (kg): Total gain per pig (kg) post-inoculation (0 DPI to 21 DPI); * pen: pen for which the total gain is calculated; * total gain (kg)/pen: the total gain (kg) per pen. **Tab name: Feedgain_results calculation** This tab provides the results of the feed to gain ratio using the calculation results from the Feedgain_feed intake and Feedgain_Pig weight tabs. Variables: * pen: pen; * total gain/pen: total gain (kg) per pen; * total feed intake/pen: total feed intake (kg) per pen; * FCR: feed conversion ratio (kg), formula in the cell; * Feed to gain: feed to gain (kg), formula in the cell; * Total growth days: total number of days allocated to growth; * Total pig growth days: total number of days all pigs in the pen had to grow; * Average gain/day/pig (based on pen calculations): average gain per day per pig (kg), formula in the cell; * Comments: comments; * treatment average feed:gain/ treatment: final result of average feed to gain (kg) per treatment; * Standard deviation (SD): standard deviation of the mean of the final result, formula in the cell. **Tab name: Feedgain_DPI periods** This tab provides the chart with dates and days for days post-inoculation (DPI) periods. Visual orientation for feed to gain, not used for calculations. **Tab name: Feedintake final results** Variables: consumption/pig/day: feed intake (kg) per pig per day **Tab name: Feedintake calculations** The layout of the tab: row 1 explains columns with or without corrections, and shows the column with the final result for the analysis Variables: * pig days: number of days the pen had for pigs to grow per period, formula in the cell; * consumption/period: consumption of feed (kg) per pen and per period; * period_2: period version two used statistical analysis; * Feed consumption/pig/from pig days: feed consumption (kg) per pig calculated from pig days, formula in the cell; consumption/pig/ * day_period2: feed consumption (kg) per pig per day per period version 2, formula in the cell. **Tab name: Feedintake_DPI periods** This tab provides the chart with dates and days for days post-inoculation (DPI) periods. Visual orientation for feed intake, not used for calculations. ## Code/software Microsoft Excel ## Access information Other publicly accessible locations of the data: * not applicable Data was derived from the following sources: * original research