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Cited by 9Effects of Environmental Stressors on LivestockBuilding Energy and Comfort OptimizationThermoregulation and physiological responses

Modeling of Ambient Environment and Thermal Status Relationship of Pig’s Body in a Pig Barn

Open access
Basak, Jayanta Kumar, Arulmozhi, Elanchezhian, Khan, Fawad, Okyere, Frank Gyan, Ahmed, Jihoon Park, Ara, Ahmed, Hyeon Tae Kim* Ara·2020·Indian Journal of Animal Research
DOI 10.18805/ijar.b-1186
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Abstract

An experiment was conducted to evaluate the performance of temperature model (T model), relative humidity model (H model), temperature-humidity model (TH model), and temperature-humidity index model (THI model) in predicting pig’s body surface temperature (PBT). Infrared Sensor (IR) was used to measure PBT at different locations: left side (LS), right side (RS), forehead (FH) and back side (BS). Ambient environmental parameters inside the room such as temperature (ART), relative humidity (RRH) and CO2 concentration were measured using livestock environment management system (LEMS). THI model was selected as the best model in making more accurate prediction in both training (R2=0.72, RMSE=0.80, RSE=0.26 and MAPE=2.08) and validation (R2=0.74, RMSE=1.10, RSE=0.40 and MAPE=2.80) stages. For more precise modeling, apart from temperature and humidity data other environmental factors inside pig’s barn (CO2 concentration, wind speed, air pressure etc.) as well as growth factors (body weight, feed intake etc.) may be included in models.

AI snapshot

Written from the paper’s full text.

TL;DR

The study developed and compared temperature (T), relative humidity (H), temperature-humidity (TH), and temperature-humidity index (THI) regression models to predict pig body surface temperature (PBT) from ambient conditions in a pig barn. The THI model was selected as the best predictor in both training and validation stages.

Key findings

  • The THI model had the best performance: training R²=0.72, RMSE=0.80, RSE=0.26, MAPE=2.08; validation R²=0.74, RMSE=1.10, RSE=0.40, MAPE=2.80.
  • The H model performed poorly, with training R²=0.23 and validation R²=0.01, while the T model had training R²=0.70 and validation R²=0.72.
  • No significant differences were found among body regions at the same time (p=0.502 in 2017 and p=0.432 in 2018); forehead temperatures were slightly higher, and left/right side temperatures were lowest.
  • Ambient room temperature was strongly correlated with PBT (r=0.84 in 2017 and r=0.86 in 2018), whereas relative humidity correlations were low (r=0.48 and r=0.11).

Methods

  • Six 10-week-old Yorkshire pigs with initial body weight 30.3±0.85 kg were used in two independent experiments at Gyeongsang National University from 15 September to 15 December in 2017 and 2018.
  • PBT was measured using four infrared sensors at left side, right side, forehead, and back side every 2 hours from 9:00 am to 17:00 pm; a livestock environment management system recorded temperature, humidity, CO₂, smoke, and wind speed every five minutes.
  • Linear and multiple linear regression models (T, H, TH, THI) were developed using n=920 observations and evaluated with R², RMSE, RSE, and MAPE using SPSS and Origin Pro, with significance at P<0.05.

Limitations

  • Stated in the paper: some limitation in accuracy is inevitable, though using a large number of samples may minimize deviations; more precise modeling should include other environmental factors (CO₂ concentration, wind speed, air pressure) and growth factors (body weight, feed intake).
  • Evident from the text: the experiment used only six pigs of one breed and age across two seasonal periods, and the final models used only ambient temperature and relative humidity despite other environmental variables being measured.
  • Evident from the text: the best THI model explained about 72–74% of the variation in PBT, and the residual plot suggested error variance changed with THI and drifted slowly over the investigation.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.18805/ijar.b-1186

Cites

22 of 22 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

5 of 16 cited sources checked · 1 supported · 0 flagged · accuracy not yet measured

  • Findingown data
    § Ambient conditions and body temperature · p. 3

    The correlations between RRH and PBT were low (r=0.48 and 0.11 in 2017 and 2018, respectively).

    “The correlations between RRH and PBT were low (r=0.48 and 0.11 in 2017 and 2018, respectively).”
    Quote in the paperSubstantial claim
  • Findingown data
    § CONCLUSION · p. 5

    Evaluation of the suggested models by validation data set observed a significant positive relationship between predicted and measured data.

    “Evaluation of the suggested models by validation data set, observed a significant positive relationship between predicted and measured data.”
    Quote in the paperSubstantial claim
  • Findingown data
    § Ambient conditions and body temperature · p. 3

    Body temperature measured in 2017 ranged from 23.9 to 38.3 C, giving a variation of 14.4 C.

    “The body temperature measured in 2017 ranged from 23.9 to 38.3  C, giving a variation of 14.4  C”
    Quote in the paperNot a substantial claim
  • Findingown data
    § Ambient conditions and body temperature · p. 3

    High PBT was observed when the ART was maximum with a low RRH.

    “High PBT was observed when the ART was maximum with a low RRH.”
    Quote in the paperSubstantial claim
  • Findingnone given
    § Ambient conditions and body temperature · p. 3

    The lowest temperatures were observed in the LS and RS.

    “The lowest temperatures were observed in the LS and RS.”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim. 15
  • May combine two claims. 12
  • The quote only partly states this claim. 1

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § INTRODUCTION · p. 1

    When pigs face heat stress, they increase their heart beat rate, respiratory frequency and peripheral blood flow to promote loss of heat.

    “When pigs face heat stress, they increase their heart beat rate, respiratory frequency and peripheral blood flow to promote loss of heat (Wilson and Crandall, 2011).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Wilson and Crandall, 2011 source

      The Heart Rate and Afterload sections report increased heart rate and cutaneous vascular conductance during heat stress. But the Introduction limits the review to human passive-thermal stress; our copy does not establish these responses in pigs or report increased respiratory frequency. (LLM, conf=0.88)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation
    § INTRODUCTION · p. 1

    At high ambient temperature and low relative humidity, pigs use a well-regulated mechanism to dissipate heat to the environment and prevent the production of excess body heat.

    “However, at high ambient temperature and low relative humidity, pigs use a well regulated mechanism to dissipate heat to the environment (Morera et al., 2012) as well as to prevent the production of excess body heat (Sagonas et al., 2013).”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites Morera et al., 2012 source

      The Introduction says that, in a hot environment, thermoregulation uses dry heat exchange and evaporative heat loss to balance heat production and heat loss. It does not establish this mechanism specifically for pigs or under low relative humidity; the study's animals were mice. The separate claim about preventing excess heat production is attached to Sagonas et al., not Morera et al. (LLM, conf=0.87)

      Experimental — accuracy not yet measured
    • cites Sagonas et al., 2013 source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation
    § INTRODUCTION · p. 1

    Temperature and relative humidity are the most pivotal parameters for life and govern maximum factors of whole-animal performance and fitness.

    “Temperature and relative humidity are the most pivotal parameters for life, and governs maximum factors of wholeanimal performance and fitness (Chakraborty et al., 2018).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Chakraborty et al., 2018 source

      The available passage is the article’s header and bibliographic information (no section or page shown); it does not discuss temperature, relative humidity, performance, or fitness. Searches for those terms and the claim’s wording found no substantive passage in our copy that addresses the claim. (LLM, conf=0.71)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § INTRODUCTION · p. 1

    When pigs face heat stress, they decrease voluntary feed intake to reduce heat production within their body.

    “They also decrease voluntary feed intake to reduce heat production within their body (Renaudeau et al., 2010).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Renaudeau et al., 2010 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § INTRODUCTION · p. 1

    At low ambient temperature and high relative humidity, pigs generate heat through increasing basal metabolism and the increased thermic effect of feed.

    “At low ambient temperature and high relative humidity, pigs generate heat through increasing basal metabolism (Adair and Black, 2003) and the increased thermic effect of feed (Levine, 2004).”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites Adair and Black, 2003 source

      The Heat Production Responses section (page unavailable) says cold can increase resting metabolic heat production, but discusses humans, not pigs. The cited passages do not establish that pigs increase basal metabolism specifically under low ambient temperature and high relative humidity. The thermic effect of feed is attributed to Levine (2004), not to this source. (LLM, conf=0.85)

      Experimental — accuracy not yet measured
    • cites Levine, 2004 source

  • May combine two claims.

    Findingown data
    § Ambient conditions and body temperature · p. 2

    The average temperature and humidity in the experimental pig barn in 2017 were 23.11±0.16 C and 64.33±0.34%, respectively.

    “The average temperature and humidity (mean±SE) in the experimental pig barn in 2017 were 23.11±0.16  C and 64.33±0.34%, respectively.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Ambient conditions and body temperature · p. 3

    The mean temperature-humidity index (THI) was 70.33±0.21 in 2017 and 68.78±0.22 in 2018.

    “The mean temperature-humidity index (THI) were 70.33±0.21 and 68.78±0.22 in 2017 and 2018, respectively.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). The quote only partly states this claim.

    Findingown data
    § Ambient conditions and body temperature · p. 3

    Temperatures obtained at forehead (FH) were slightly higher compared to the left side (LS), right side (RS) and back side (BS).

    “It was observed that temperatures obtained at forehead (FH) were slightly higher as compared to the left side (LS), right side”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § ABSTRACT · p. 1

    The THI model was the best among the four models in predicting PBT, with training R2=0.72, RMSE=0.80, RSE=0.26, MAPE=2.08 and validation R2=0.74, RMSE=1.10, RSE=0.40, MAPE=2.80.

    “THI model was selected as the best model in making more accurate prediction in both training (R 2 =0.72, RMSE=0.80, RSE=0.26 and MAPE=2.08) and validation (R 2 =0.74, RMSE=1.10, RSE=0.40 and MAPE=2.80) stages.”
    • Also stated in: § Model development and sensitivity analysis · p. 3 · plain
      “The THI model had the best performance due to the least RMSE, MAPE, RSE and the highest R 2 values in both training and validation.”
    • Also stated in: § Model development and sensitivity analysis · p. 3 · plain
      “As shown in the result, the THI model with two input valuables (ART and RRH) given the best results in both training (R 2 =0.72, RMSE=0.80, MAPE=2.08 and RSE=0.26) and validation (R 2 =0.74, RMSE=1.10, MAPE=2.80 and RSE=0.40).”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The temperature-humidity index formula developed by Mader et al. (2006) is applicable to pigs.

  • May combine two claims.

    Findingown data
    § Model development and sensitivity analysis · p. 5

    There were several higher values for some samples, indicating that the error variance increases with THI, while a distribution of lower values shows that the error variance decreases with THI.

    “There were several higher values for some samples, indicating that the error variance increases with THI, while a distribution of lower values shows that the error variance decreases with THI.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Model development and sensitivity analysis · p. 3

    The selected THI model could predict PBT for training and validation with a 2.8% and 4.0% increase in R2 and a reduction of 3.6% and 5.2% in RMSE and 1.0% and 3.4% in MAPE, respectively, as compared to the T model.

    “The selected THI model could predict PBT for training and validation with a 2.8% and 4.0% increase in R 2 and a reduction of 3.6% and 5.2% in RMSE and 1.0% and 3.4% in MAPE, respectively as compared to the T model.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The temperature-humidity index formula developed by Mader et al. (2006) is applicable to pigs.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data
    § Model development and sensitivity analysis · p. 5

    The residual plot suggests that the models were drifting slowly to higher values as the investigation continued.

    “The residual plot suggests that the models were drifting slowly to higher values as the investigation continued.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Model development and sensitivity analysis · p. 3

    The THI model had an increase in R2 (2.8% in training and 2.6% in validation) and a reduction of RMSE (3.6% and 8.3% in training and validation, respectively) as well as a decline in MAPE (1.0% and 5.7% in training and validation, respectively) as compared to the TH model.

    “Moreover, it was also found that the THI model calculated with an increase in R 2 (2.8% in training and 2.6% in validation) and a reduction of RMSE (3.6% and 8.3% in training and validation, respectively) as well as a decline in MAPE (1.0% and 5.7% in training and validation, respectively) as compared to TH model.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The temperature-humidity index formula developed by Mader et al. (2006) is applicable to pigs.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationcitation
    § Ambient conditions and body temperature · p. 3

    The study's measured body surface temperature range was in agreement with the previously reported range of 17 to 35 C (Costa et al., 2010).

    “It has been reported that the body surface temperature of pig ranged from 17 to 35  C (Costa et al., 2010), which was in agreement with the result of the study.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Costa et al., 2010

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Interpretationcitation
    § Ambient conditions and body temperature · p. 3

    The range of THI (63.2-77.3) during the experimental periods indicates the absence of heat stress as proposed by Lucas et al. (2000), which states that a THI<75 generally does not cause safety problems for healthy pigs.

    “The rage of THI (63.2-77.3) during the experimental periods indicates the absence of heat stress as proposed by Lucas et al. (2000) which states that a THI&lt;75 generally does not cause safety problems for healthy pigs.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Lucas et al. (2000)

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § INTRODUCTION · p. 1

    Morales et al. (2016) reported that an increment of up to 2.0 C in body temperature exposes pigs to high ambient temperature.

    “Morales et al. (2016) reported that an increment of up to 2.0  C in the body temperature exposes pigs to high ambient temperature.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Morales et al. (2016) source

  • Classified as probably not a substantial claim.

    Premisecitation
    § INTRODUCTION · p. 1

    As homeothermic animals, pigs preserve their body temperature relatively constant over a certain range of ambient temperatures and relative humidity.

    “As homeothermic animals, pigs preserve their body temperature relatively constant over a certain range of ambient temperatures and relative humidity (Rezende and Bacigalupe, 2015).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Rezende and Bacigalupe, 2015 source

  • Probably not a substantial claim: may not pass S4 (based). May combine two claims.

    Interpretationnone given
    § INTRODUCTION · p. 1

    Regression-based models (T, H, TH and THI) for estimating body temperature can reduce sampling effort and cost and may increase precision where samples are difficult to handle.

    “Such regression based models (T, H, TH and THI) for estimating body temperature can reduce sampling effort and cost and may increase precision where samples are difficult to handle.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing).

    Interpretationnone given
    § CONCLUSION · p. 5

    Some limitation in accuracy is inevitable.

    “Some limitation in accuracy is inevitable”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation
    § Ambient conditions and body temperature · p. 3

    THI falls into alert and mild discomfort conditions when in the range of 75 to 78 and under dangerous condition in above 79.

    “THI falls into alert and mild discomfort conditions when in the range of 75 to 78 and under dangerous condition in above 79.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Lucas et al. (2000)

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Classified as probably not a substantial claim. May combine two claims.

    Interpretationown data
    § CONCLUSION · p. 5

    These models provide a very simple form, more accurate and time saving tool to predict pig's body temperature.

    “These models provide a very simple form, more accurate and time saving tool to predict pig's body temperature.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationcitation
    § Ambient conditions and body temperature · p. 3

    The present result is in close accordance with the findings of Warriss et al. (2006) who noted that temperature data obtained in the eye region using infrared thermography (IRT) were higher compared to the other parts of pig's body.

    “The present result are in close accordance with the findings of Warriss et al. (2006) who noted that temperature data obtained in the eye region using infrared thermography (IRT) were higher compared to the other parts of pig's body.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Warriss et al. (2006) source
22 of 22

  • The paper relies on this without support.

    The infrared sensor measurements at 20 cm perpendicular to the pig's body accurately represent pig body surface temperature.

    “skin surface temperature on four different body positions of each pig: left side (LS), right side (RS), forehead (FH) and back side (BS) were measured at the same time using four infrared sensors (IR sensor, model-MI3, Raytek corporation, California, USA) at a fixed distance (20 cm) and positioned perpendicularly to the pig' body”

  • The paper relies on this without support.

    The body surface temperature measured at four body locations represents the pig's overall thermal status.

    “Infrared Sensor (IR) was used to measure PBT at different locations: left side (LS), right side (RS), forehead (FH) and back side (BS).”

  • The paper relies on this without support.

    The temperature-humidity index formula developed by Mader et al. (2006) is applicable to pigs.

    “Temperature humidity index (THI) values were calculated as described by Mader et al. (2006).”
3 of 3

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Reported THI range includes an alert condition

    Minor

    The reported THI range reaches 77.3, which falls within the paper's stated alert and mild-discomfort range of 75 to 78. The range therefore does not support the stated absence of heat stress throughout the experimental periods.

1 of 1

Cites

Flagged first, then by citations

3 of the 25 references couldn’t be matched to a known paper.

Research works printed but not linked: 2

  1. Albright, J.L. (1993). Feeding behaviour of dairy cattle. Journal of Dairy Science. 76: 485-498. DOI: org/10.3168/jds.S00220302 (93)77369-5. · DOI
  2. Ramesh, V., Saseendran, P.C. (2002). Effect of enrichment of environment for better economic reproductive performance of sows. Indian Journal of Animal Research. 36(2): 98-101.

Cited by

Sorted by citations

Related

Authors
Basak, J. K., Arulmozhi, E., Khan, F., Okyere, F. G., Ahmed, J. P., & Ahmed, H. T. K. A.
Affiliations
Gyeongsang National University (KR)
ORCID
Venue
Indian Journal of Animal Research
Publisher
Agricultural Research Communication Center
Published
2020-01-23
Issue
of
ISSN
  • 0367-6722 (ISSN-L)
  • 0976-0555
DOI
10.18805/ijar.b-1186
OpenAlex
W3007565486
Semantic Scholar
df299214f4d478dfd02225a09d4861a0a9b80839
Cited by
9
References
25
Citations by year
2026: 1 · 2025: 1 · 2024: 2 · 2023: 1 · 2022: 3 · 2021: 1
FWCI
0.88
Type
journal article
Language
en
Open access
Licence
cc-by
Locations
Indian Journal of Animal Research (publishedVersion, cc-by)
Topics
  • Life Sciences › Agricultural and Biological Sciences › Animal Science and Zoology › Effects of Environmental Stressors on Livestock
  • Physical Sciences › Engineering › Building and Construction › Building Energy and Comfort Optimization
  • Health Sciences › Medicine › Physiology › Thermoregulation and physiological responses
Keywords
temperature-humidity index, thermal comfort, relative humidity, ambient temperature, infrared thermography, CO2 concentration, pig housing

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