Tear staining in pigs: a potential tool for welfare assessment on commercial farms

H. Telkänranta, J. N. Matchant-Forde, A. Valros

Research output: Contribution to journalArticleScientificpeer-review

Abstract

Tear staining or chromodacryorrhea refers to a dark stain below the inner corner of the eye, caused by porphyrin-pigmented secretion from the Harderian gland. It has been shown to be a consistent indicator of stress in rats and to correlate with social stress and a barren environment in pigs. The current study was, to our knowledge, the first to test it on commercial pig farms as a potential welfare indicator. The study was carried out on three commercial farms in Finland, in connection to a larger study on the effects of different types of manipulable objects on tail and ear biting and other behavioural parameters. Farm A was a fattening farm, on which 768 growing-finishing pigs were studied in 73 pens. Farm B had a fattening unit, in which 656 growing-finishing pigs were studied in 44 pens, and a farrowing unit, in which 29 sows and their litters totalling 303 piglets were studied in 29 pens. Farm C was a piglet-producing farm, on which 167 breeder gilts were studied in 24 pens. Data collection included individual-level scoring of tear staining; scoring of tail and ear damage in the growing-finishing pigs and breeder gilts; a novel object test for the piglets; and a novel person test for the growing-finishing pigs on Farm B and the breeder gilts on Farm C. On Farm A, tear staining was found to correlate with tail damage scores (n=768, r s =0.14, P<0.001) and ear damage scores (n=768, r s =0.16, P<0.001). In the growing-finishing pigs on Farm B, tear staining of the left eye correlated with tail damage (n=656, r s =0.12, P<0.01) and that of the right eye correlated with ear damage (n=656, r s =0.10, P<0.01). On Farm A, tear-staining sores were lower in the treatment with three different types of manipulable objects as compared with controls (mean scores 3.3 and 3.9, respectively, n=31, F29=4.2, P<0.05). In the suckling piglets on Farm B, tear staining correlated with the latency to approach a novel object (n=29, r p =0.41, P<0.05). Although correlations with tail and ear damage were low, it was concluded that tear staining has promising potential as a new, additional welfare indicator for commercial pig farming. Further research is needed on the mechanisms of tear staining.
Original languageEnglish
JournalAnimal
Volume10
Issue number2
Pages (from-to)318-325
Number of pages8
ISSN1751-7311
DOIs
Publication statusPublished - 2016
MoE publication typeA1 Journal article-refereed

Fields of Science

  • 413 Veterinary science
  • pig
  • tear staining
  • tail biting
  • ear biting
  • enrichment
  • HARDERIAN-GLAND
  • EXPLORATORY-BEHAVIOR
  • LABORATORY RATS
  • TAIL
  • STRESS
  • ENRICHMENT
  • PORPHYRIN

Cite this

@article{87923ca364c04184810fd831dc4f04d2,
title = "Tear staining in pigs: a potential tool for welfare assessment on commercial farms",
abstract = "Tear staining or chromodacryorrhea refers to a dark stain below the inner corner of the eye, caused by porphyrin-pigmented secretion from the Harderian gland. It has been shown to be a consistent indicator of stress in rats and to correlate with social stress and a barren environment in pigs. The current study was, to our knowledge, the first to test it on commercial pig farms as a potential welfare indicator. The study was carried out on three commercial farms in Finland, in connection to a larger study on the effects of different types of manipulable objects on tail and ear biting and other behavioural parameters. Farm A was a fattening farm, on which 768 growing-finishing pigs were studied in 73 pens. Farm B had a fattening unit, in which 656 growing-finishing pigs were studied in 44 pens, and a farrowing unit, in which 29 sows and their litters totalling 303 piglets were studied in 29 pens. Farm C was a piglet-producing farm, on which 167 breeder gilts were studied in 24 pens. Data collection included individual-level scoring of tear staining; scoring of tail and ear damage in the growing-finishing pigs and breeder gilts; a novel object test for the piglets; and a novel person test for the growing-finishing pigs on Farm B and the breeder gilts on Farm C. On Farm A, tear staining was found to correlate with tail damage scores (n=768, r s =0.14, P<0.001) and ear damage scores (n=768, r s =0.16, P<0.001). In the growing-finishing pigs on Farm B, tear staining of the left eye correlated with tail damage (n=656, r s =0.12, P<0.01) and that of the right eye correlated with ear damage (n=656, r s =0.10, P<0.01). On Farm A, tear-staining sores were lower in the treatment with three different types of manipulable objects as compared with controls (mean scores 3.3 and 3.9, respectively, n=31, F29=4.2, P<0.05). In the suckling piglets on Farm B, tear staining correlated with the latency to approach a novel object (n=29, r p =0.41, P<0.05). Although correlations with tail and ear damage were low, it was concluded that tear staining has promising potential as a new, additional welfare indicator for commercial pig farming. Further research is needed on the mechanisms of tear staining.",
keywords = "413 Veterinary science, pig, tear staining, tail biting, ear biting , enrichment , HARDERIAN-GLAND , EXPLORATORY-BEHAVIOR , LABORATORY RATS , TAIL , STRESS , ENRICHMENT , PORPHYRIN",
author = "H. Telk{\"a}nranta and Matchant-Forde, {J. N.} and A. Valros",
year = "2016",
doi = "10.1017/S175173111500172X",
language = "English",
volume = "10",
pages = "318--325",
journal = "Animal",
issn = "1751-7311",
publisher = "Cambridge University Press",
number = "2",

}

Tear staining in pigs: a potential tool for welfare assessment on commercial farms. / Telkänranta, H.; Matchant-Forde, J. N.; Valros, A.

In: Animal, Vol. 10, No. 2, 2016, p. 318-325.

Research output: Contribution to journalArticleScientificpeer-review

TY - JOUR

T1 - Tear staining in pigs: a potential tool for welfare assessment on commercial farms

AU - Telkänranta, H.

AU - Matchant-Forde, J. N.

AU - Valros, A.

PY - 2016

Y1 - 2016

N2 - Tear staining or chromodacryorrhea refers to a dark stain below the inner corner of the eye, caused by porphyrin-pigmented secretion from the Harderian gland. It has been shown to be a consistent indicator of stress in rats and to correlate with social stress and a barren environment in pigs. The current study was, to our knowledge, the first to test it on commercial pig farms as a potential welfare indicator. The study was carried out on three commercial farms in Finland, in connection to a larger study on the effects of different types of manipulable objects on tail and ear biting and other behavioural parameters. Farm A was a fattening farm, on which 768 growing-finishing pigs were studied in 73 pens. Farm B had a fattening unit, in which 656 growing-finishing pigs were studied in 44 pens, and a farrowing unit, in which 29 sows and their litters totalling 303 piglets were studied in 29 pens. Farm C was a piglet-producing farm, on which 167 breeder gilts were studied in 24 pens. Data collection included individual-level scoring of tear staining; scoring of tail and ear damage in the growing-finishing pigs and breeder gilts; a novel object test for the piglets; and a novel person test for the growing-finishing pigs on Farm B and the breeder gilts on Farm C. On Farm A, tear staining was found to correlate with tail damage scores (n=768, r s =0.14, P<0.001) and ear damage scores (n=768, r s =0.16, P<0.001). In the growing-finishing pigs on Farm B, tear staining of the left eye correlated with tail damage (n=656, r s =0.12, P<0.01) and that of the right eye correlated with ear damage (n=656, r s =0.10, P<0.01). On Farm A, tear-staining sores were lower in the treatment with three different types of manipulable objects as compared with controls (mean scores 3.3 and 3.9, respectively, n=31, F29=4.2, P<0.05). In the suckling piglets on Farm B, tear staining correlated with the latency to approach a novel object (n=29, r p =0.41, P<0.05). Although correlations with tail and ear damage were low, it was concluded that tear staining has promising potential as a new, additional welfare indicator for commercial pig farming. Further research is needed on the mechanisms of tear staining.

AB - Tear staining or chromodacryorrhea refers to a dark stain below the inner corner of the eye, caused by porphyrin-pigmented secretion from the Harderian gland. It has been shown to be a consistent indicator of stress in rats and to correlate with social stress and a barren environment in pigs. The current study was, to our knowledge, the first to test it on commercial pig farms as a potential welfare indicator. The study was carried out on three commercial farms in Finland, in connection to a larger study on the effects of different types of manipulable objects on tail and ear biting and other behavioural parameters. Farm A was a fattening farm, on which 768 growing-finishing pigs were studied in 73 pens. Farm B had a fattening unit, in which 656 growing-finishing pigs were studied in 44 pens, and a farrowing unit, in which 29 sows and their litters totalling 303 piglets were studied in 29 pens. Farm C was a piglet-producing farm, on which 167 breeder gilts were studied in 24 pens. Data collection included individual-level scoring of tear staining; scoring of tail and ear damage in the growing-finishing pigs and breeder gilts; a novel object test for the piglets; and a novel person test for the growing-finishing pigs on Farm B and the breeder gilts on Farm C. On Farm A, tear staining was found to correlate with tail damage scores (n=768, r s =0.14, P<0.001) and ear damage scores (n=768, r s =0.16, P<0.001). In the growing-finishing pigs on Farm B, tear staining of the left eye correlated with tail damage (n=656, r s =0.12, P<0.01) and that of the right eye correlated with ear damage (n=656, r s =0.10, P<0.01). On Farm A, tear-staining sores were lower in the treatment with three different types of manipulable objects as compared with controls (mean scores 3.3 and 3.9, respectively, n=31, F29=4.2, P<0.05). In the suckling piglets on Farm B, tear staining correlated with the latency to approach a novel object (n=29, r p =0.41, P<0.05). Although correlations with tail and ear damage were low, it was concluded that tear staining has promising potential as a new, additional welfare indicator for commercial pig farming. Further research is needed on the mechanisms of tear staining.

KW - 413 Veterinary science

KW - pig

KW - tear staining

KW - tail biting

KW - ear biting

KW - enrichment

KW - HARDERIAN-GLAND

KW - EXPLORATORY-BEHAVIOR

KW - LABORATORY RATS

KW - TAIL

KW - STRESS

KW - ENRICHMENT

KW - PORPHYRIN

U2 - 10.1017/S175173111500172X

DO - 10.1017/S175173111500172X

M3 - Article

VL - 10

SP - 318

EP - 325

JO - Animal

JF - Animal

SN - 1751-7311

IS - 2

ER -