Evidence map›Paper›PMID 33583422›Full record

ReviewJournal of animal science and biotechnology2021

Review of the impact of heat stress on reproductive performance of sheep.

William H E J van Wettere, Karen L Kind, Kathryn L Gatford, Alyce M Swinbourne, Stephan T Leu, Peter T Hayman, Jennifer M Kelly, Alice C Weaver, David O Kleemann, Simon K Walker

Open access · goldAbstract readReview
PubMed Full text at PMC Publisher
In one paragraph

Review in Journal of animal science and biotechnology, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 73 papers.

0numbers the graph read from it
0cells of the map it votes in
73citing papers in PubMed
21.4field-weighted citation impact, top 1% of its field
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

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

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

73 citing papers in PubMed, 174 citations in OpenAlex.

  1. Article
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  9. Review
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  13. Review
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  15. Breed and Season: Key Determinants of Efficiency in Large-Scale CommercialAnimals : an open access journal from MDPI · 2025
    Article
  16. Article
  17. Article
  18. Genomic Insights into the Origin, High Fecundity and Environmental Adaptation of Hu Sheep.Advanced science (Weinheim, Baden-Wurttemberg, Germany) · 2025
    Article
  19. Article
  20. Article

13 more citing papers are in PubMed but not listed here.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

10 authors at 2 institutions in 1 country.

William H E J van WettereThe University of Adelaide, School of Animal and Veterinary Sciences, Davies Livestock Research Centre, Roseworthy Campus, Mudla Wirra Rd, Roseworthy, South Australia, 5371, Australia. william.vanwettere@adelaide.edu.au.
Karen L KindThe University of Adelaide, School of Animal and Veterinary Sciences, Davies Livestock Research Centre, Roseworthy Campus, Mudla Wirra Rd, Roseworthy, South Australia, 5371, Australia.
Kathryn L GatfordThe University of Adelaide, Robinson Research Institute, Adelaide Medical School, North Terrace, Adelaide, South Australia, 5000, Australia.
Alyce M SwinbourneThe University of Adelaide, School of Animal and Veterinary Sciences, Davies Livestock Research Centre, Roseworthy Campus, Mudla Wirra Rd, Roseworthy, South Australia, 5371, Australia.
Stephan T LeuThe University of Adelaide, School of Animal and Veterinary Sciences, Davies Livestock Research Centre, Roseworthy Campus, Mudla Wirra Rd, Roseworthy, South Australia, 5371, Australia.
Peter T HaymanThe University of Adelaide, School of Agriculture, Food and Wine, Waite Research Institute, Urrbrae, South Australia, 5064, Australia.
Jennifer M KellyThe University of Adelaide, School of Animal and Veterinary Sciences, Davies Livestock Research Centre, Roseworthy Campus, Mudla Wirra Rd, Roseworthy, South Australia, 5371, Australia.
Alice C WeaverThe University of Adelaide, School of Animal and Veterinary Sciences, Davies Livestock Research Centre, Roseworthy Campus, Mudla Wirra Rd, Roseworthy, South Australia, 5371, Australia.
David O KleemannThe University of Adelaide, School of Animal and Veterinary Sciences, Davies Livestock Research Centre, Roseworthy Campus, Mudla Wirra Rd, Roseworthy, South Australia, 5371, Australia.
Simon K WalkerSouth Australian Research and Development Institute, Primary Industries and Regions SA, Reproductive Biology, Livestock Sciences, Turretfield Research Centre, 129 Holland Rd, Rosedale, South Australia, 5350, Australia.
University of Adelaide · AUSouth Australian Research and Development Institute · AU

Funding

Meat and Livestock Australia L.LSM.0024
6 · The paper itself

Abstract

Heat stress significantly impairs reproduction of sheep, and under current climatic conditions is a significant risk to the efficiency of the meat and wool production, with the impact increasing as global temperatures rise. Evidence from field studies and studies conducted using environmental chambers demonstrate the effects of hot temperatures (≥ 32 °C) on components of ewe fertility (oestrus, fertilisation, embryo survival and lambing) are most destructive when experienced from 5 d before until 5 d after oestrus. Temperature controlled studies also demonstrate that ram fertility, as measured by rates of fertilisation and embryo survival, is reduced when mating occurs during the period 14 to 50 d post-heating. However, the contribution of the ram to heat induced reductions in flock fertility is difficult to determine accurately. Based primarily on temperature controlled studies, it is clear that sustained exposure to high temperatures (≥ 32 °C) during pregnancy reduces lamb birthweight and will, therefore, decrease lamb survival under field conditions. It is concluded that both ewe and ram reproduction is affected by relatively modest levels of heat stress (≥ 32 °C) and this is a concern given that a significant proportion of the global sheep population experiences heat stress of this magnitude around mating and during pregnancy. Despite this, strategies to limit the impacts of the climate on the homeothermy, behaviour, resource use and reproduction of extensively grazed sheep are limited, and there is an urgency to improve knowledge and to develop husbandry practices to limit these impacts.

Indexed as

FertilityHeat stressOogenesisPregnancySheepSpermatogenesis

Identifiers

PMID33583422
PMCPMC7883430
OpenAlexW3131377205

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

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 OpenQuestion graph.