Evidence map›Paper›PMID 42837012›Full record

ArticleInternational journal of biometeorology2026

The effect of Temperature-Humidity Index (THI) on the number of stillbirths and stress-to-comfort ratio of sows at different parities in a tropical environment.

Amanda Aparecida Brito, Natascha Almeida Marques da Silva, Edmilson Rodrigues Pinto, Ana Luísa Neves Alvarenga Dias, Mara Regina Bueno de Mattos Nascimento

Abstract read
In one paragraph

Article in International journal of biometeorology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0cells of the map it votes in
0citing papers in PubMed
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1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

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4 · The record

Corrections and comments

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5 · Who and what money

Authors and funding

5 authors.

Amanda Aparecida BritoFaculty of Veterinary Medicine and Zootechnics, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil. amanda.brito@ufu.br.ORCID http://orcid.org/0000-0003-0042-2484
Natascha Almeida Marques da SilvaFaculty of Veterinary Medicine and Zootechnics, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil.ORCID http://orcid.org/0000-0003-2318-1791
Edmilson Rodrigues PintoInstitute of Mathematics and Statistics, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil.ORCID http://orcid.org/0000-0003-3673-9328
Ana Luísa Neves Alvarenga DiasFaculty of Veterinary Medicine and Zootechnics, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil.ORCID http://orcid.org/0000-0002-2790-614X
Mara Regina Bueno de Mattos NascimentoFaculty of Veterinary Medicine and Zootechnics, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil.ORCID http://orcid.org/0000-0003-4324-5262

Funding

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Finance Code 001
6 · The paper itself

Abstract

It is well known that heat stress negatively affects the productivity, reproduction, and welfare of pigs. However, the role of thermal environments and stress-to-comfort (S/C) ratios in predicting stillbirths has not been studied in tropical regions. Therefore, this study aimed to model and estimate the impact of the maximum Temperature-Humidity Index (THImax) on the number of stillborn piglets and to calculate the S/C ratio. A total of 36,880 farrowings from sows on a commercial farm in Brazil were analyzed. The females were grouped by parity into gilts, primiparous, and multiparous with 2-5 and ≥ 6 farrowings. On the day of farrowing, THImax was classified as follows: ≤74 (thermal comfort), 75-78 (mild stress), 79-82 (moderate stress), and > 82 (severe stress). The effect of THImax on the number of stillbirths per day was estimated using quasi-Poisson regression. The models were adjusted using the quasi-Akaike information criterion (QAIC) and Pearson's residual variance to select the most appropriate model for the data. Also to analyze the mean number of stillbirths per farrowing by THImax category using one-way ANOVA. Then, the S/C ratio was calculated by THImax category. Of the 1,826 total days, 14.95% were classified as comfortable. According to the model, multiparous sows (≥ 2 farrowings) had more stillbirths per day under THImax > 82, while in primiparous sows, ITUmax < 74 is associated with the highest number of stillbirths per day, with a reduction as ITUmax approaches 74. With the severe S/C ratio, an increase in stillbirths per litter was observed in gilts (20%), primiparous (7%), 2-5 parities (14%), and ≥ 6 parities (19%). The quasi-Poisson model indicated an increase in daily stillbirths in multiparous sows (≥ 2 farrowings) under THImax > 82. The severe S/C ratio was greater than 1 in all parity groups, indicating an increase in the average number of stillbirths per farrowing, mainly under THImax > 82.

Indexed as

HumidityStillbirthAnimalsBrazilFemaleParityPregnancyStress, PhysiologicalSwineTemperatureThermal ComfortTropical ClimateHeat stressPigPigletReproductive performanceThermal comfortThermoneutral zone

Identifiers

PMID42837012
PMCPMC13642494

What Socratic holds

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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.