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Infrared Thermography to Evaluate Heat Tolerance in Different Genetic Groups of Lambs.

McManus C, Bianchini E, Paim Tdo P, de Lima FG, Neto JB, Castanheira M, Esteves GI, Cardoso CC, Dalcin VC - Sensors (Basel) (2015)

Bottom Line: Heat stress is considered a limiting factor for sheep production.Forty-eight four-month-old male lambs from eight genetic groups were used.Statistical analyses included variance, correlations, factor, discrimination and regression.

View Article: PubMed Central - PubMed

Affiliation: Faculdade de Agronomia e Medicina Veterinária, Universidade de Brasília, Brasília 70910-900, DF, Brasil. concepta.mcmanus@ufrgs.br.

ABSTRACT
Heat stress is considered a limiting factor for sheep production. We used information from physiological characteristics linked to heat tolerance to determine whether infrared thermography temperatures were able to separate groups of animals and determine the most important variables in this differentiation. Forty-eight four-month-old male lambs from eight genetic groups were used. Physiological (rectal temperature-RT, heart rate-HR, respiratory rate-RR) and blood traits, infrared thermography temperatures, heat tolerance indices, body measurements, weight and carcass traits were measured. Statistical analyses included variance, correlations, factor, discrimination and regression. Observing the correlations between physiological characteristics (RT, RR and HR) with temperatures measured by infrared thermography, regions for further studies should include the mean temperature of flank, nose and rump. Results show that there are strong relationships between thermograph measurements and RR, RT and HR in lambs, which are suggested to be directly correlated with heat tolerance capacity of the different genetic groups evaluated in this study. The assessment of body surface temperature measured by the thermograph could be used as a noninvasive tool to assess heat tolerance of the animals.

No MeSH data available.


Related in: MedlinePlus

First two principal components for adaptability tests, physiological variables and infrared temperatures in lambs during the morning (A) and afternoon (B). BL: Body Length (cm); LB: Length of Back (cm); HG: heart girth (cm); SH: Shoulder Height (cm); Flank, Head, Nose, Neck, Stifle and croup: thermography temperatures (°C), HR: heart rate (beats/min); RR: respiratory rate (mov/min); RT: rectal temperature (°C), Iberia: Iberia test; Benezra: Benezra test; RY: Rauschenbach–Yerokhin test; Baccari: Baccari Jr. test.
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sensors-15-17258-f003: First two principal components for adaptability tests, physiological variables and infrared temperatures in lambs during the morning (A) and afternoon (B). BL: Body Length (cm); LB: Length of Back (cm); HG: heart girth (cm); SH: Shoulder Height (cm); Flank, Head, Nose, Neck, Stifle and croup: thermography temperatures (°C), HR: heart rate (beats/min); RR: respiratory rate (mov/min); RT: rectal temperature (°C), Iberia: Iberia test; Benezra: Benezra test; RY: Rauschenbach–Yerokhin test; Baccari: Baccari Jr. test.

Mentions: In the morning, the Iberia and Rauschenbach–Yerokhin tests, which used RT in the formula, were in different components than Benezra which also used RR (Figure 3). In the afternoon, the Baccari index passed to the second factor; that is, increasing RT decreased the Baccari index score indicating lower adaptation of the animal. In the afternoon, RT was close to zero and RR maintained its location, alongside Benezra (Figure 3).


Infrared Thermography to Evaluate Heat Tolerance in Different Genetic Groups of Lambs.

McManus C, Bianchini E, Paim Tdo P, de Lima FG, Neto JB, Castanheira M, Esteves GI, Cardoso CC, Dalcin VC - Sensors (Basel) (2015)

First two principal components for adaptability tests, physiological variables and infrared temperatures in lambs during the morning (A) and afternoon (B). BL: Body Length (cm); LB: Length of Back (cm); HG: heart girth (cm); SH: Shoulder Height (cm); Flank, Head, Nose, Neck, Stifle and croup: thermography temperatures (°C), HR: heart rate (beats/min); RR: respiratory rate (mov/min); RT: rectal temperature (°C), Iberia: Iberia test; Benezra: Benezra test; RY: Rauschenbach–Yerokhin test; Baccari: Baccari Jr. test.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4541933&req=5

sensors-15-17258-f003: First two principal components for adaptability tests, physiological variables and infrared temperatures in lambs during the morning (A) and afternoon (B). BL: Body Length (cm); LB: Length of Back (cm); HG: heart girth (cm); SH: Shoulder Height (cm); Flank, Head, Nose, Neck, Stifle and croup: thermography temperatures (°C), HR: heart rate (beats/min); RR: respiratory rate (mov/min); RT: rectal temperature (°C), Iberia: Iberia test; Benezra: Benezra test; RY: Rauschenbach–Yerokhin test; Baccari: Baccari Jr. test.
Mentions: In the morning, the Iberia and Rauschenbach–Yerokhin tests, which used RT in the formula, were in different components than Benezra which also used RR (Figure 3). In the afternoon, the Baccari index passed to the second factor; that is, increasing RT decreased the Baccari index score indicating lower adaptation of the animal. In the afternoon, RT was close to zero and RR maintained its location, alongside Benezra (Figure 3).

Bottom Line: Heat stress is considered a limiting factor for sheep production.Forty-eight four-month-old male lambs from eight genetic groups were used.Statistical analyses included variance, correlations, factor, discrimination and regression.

View Article: PubMed Central - PubMed

Affiliation: Faculdade de Agronomia e Medicina Veterinária, Universidade de Brasília, Brasília 70910-900, DF, Brasil. concepta.mcmanus@ufrgs.br.

ABSTRACT
Heat stress is considered a limiting factor for sheep production. We used information from physiological characteristics linked to heat tolerance to determine whether infrared thermography temperatures were able to separate groups of animals and determine the most important variables in this differentiation. Forty-eight four-month-old male lambs from eight genetic groups were used. Physiological (rectal temperature-RT, heart rate-HR, respiratory rate-RR) and blood traits, infrared thermography temperatures, heat tolerance indices, body measurements, weight and carcass traits were measured. Statistical analyses included variance, correlations, factor, discrimination and regression. Observing the correlations between physiological characteristics (RT, RR and HR) with temperatures measured by infrared thermography, regions for further studies should include the mean temperature of flank, nose and rump. Results show that there are strong relationships between thermograph measurements and RR, RT and HR in lambs, which are suggested to be directly correlated with heat tolerance capacity of the different genetic groups evaluated in this study. The assessment of body surface temperature measured by the thermograph could be used as a noninvasive tool to assess heat tolerance of the animals.

No MeSH data available.


Related in: MedlinePlus