Studies of rectal temperature, respiratory rates and heat tolerance in cattle in the humid tropics

ABSTRACTThe rectal temperature and respiratory rates of German Brown, Friesian, German Brown/Friesian crosses, N'Dama and German Brown/N'Dama (BN) crosses were studied with a view to establishing baseline data for cattle in the humid tropical environment of Nigeria.Mean morning (38·62°C) and late afternoon (39·19°C) rectal temperatures for the various breeds were found to differ significantly (P<0·01). However, general breed differences as well as differences between heifers, milking cows, bulls and calves were not significant. Respiratory rates (counts/min) were also significantly higher (P<0·01) in the afternoon than in the morning and appeared related to changes in atmospheric temperature and relative humidity. Breed differences in respiratory rates were also significant, being within the range 17 to 34 in N'Dama, 24 to 43 in BNs and 29 to 51 in the German Brown and Friesian.Heat tolerance indices were very high (89 to 91) for all the breeds studied but showed that the Friesian and German Brown were less heat tolerant than the BNs, and the N'Dama and White Fulani. The results indicate the need to consider diurnal changes in rectal temperature and respiratory rates in the use of these parameters for clinical diagnostic purposes.

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Genetic variation of rectal temperature and its relationship to milk production in Holstein dairy cows

Proceedings of the British Society of Animal Science ◽

10.1017/s1752756200029021 ◽

2009 ◽

Vol 2009 ◽

pp. 63-63

Author(s):

S Khalajzade ◽

N Emam Jomeh ◽

A Salehi ◽

A Moghimi Esfandabadi

Keyword(s):

Heat Stress ◽

Dairy Cows ◽

Milk Production ◽

Heat Tolerance ◽

Rectal Temperature ◽

Weather Factors ◽

And Performance ◽

Very High ◽

Selection Of ◽

Holstein Dairy Cows

Milk production is significantly decreased by thermal stress. The survival and performance of an animal during heat stress periods depend on several weather factors, especially temperature and humidity. Researchers reported dramatic decreases in milk production as temperature rose above 30 degree of centigrade. Very high environmental temperature is common during the summer months in Iran. Rectal temperature is as indicator of heat tolerance and has been the most frequently used physiological variable for estimating heat tolerance in cattle. Some dairy cows are more heat tolerant and productive when subjected to heat stress. Identification and selection of heat stress resistant cattle offers the potential to increase milk yield in tropical environment. The aim of the present study was to estimate genetic parameters of heat tolerance and its relationship to milk production in Holstein Dairy Cows in Iran.

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Heat tolerance of different genetic groups of sheep exposed to elevated temperature conditions

The Journal of Agricultural Science ◽

10.1017/s0021859600027908 ◽

1980 ◽

Vol 94 (1) ◽

pp. 63-67 ◽

Cited By ~ 8

Author(s):

M. Singh ◽

T. More ◽

A. K. Rai

Keyword(s):

Thermal Stress ◽

Elevated Temperature ◽

Heat Tolerance ◽

Rectal Temperature ◽

Physiological Responses ◽

Pronounced Increase ◽

Genetic Groups ◽

Heat Tolerant ◽

Increasing Temperature ◽

Frequency Of Respiration

SummaryIndian Chokla and Malpura and their crosses with exotic Rambouillet and pure bred Rambouillet sheep were exposed to increasing temperature (20, 25, 30, 35 and 42 °C), or to 40 °C for 6 ha day for about a week, or suddenly to 40·4 or 44·2 °C to study their relative heat tolerance. Pronounced increase in the frequency of respiration under hot conditions together with increase in rectal temperature (under 44·2 °C) of Rambouillet contrasted with the physiological responses of the native breeds of sheep. Under thermal stress the Chokla and Malpura consumed more feed than the Rambouillet or the half breds. The Rambouillet × Chokla or the Rambouillet × Malpurahalf breds were apparently more heat tolerant than the Rambouillet sheep.

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The effect of duration of heat stress during grain filling on two wheat varieties differing in heat tolerance: grain growth and fractional protein accumulation

Functional Plant Biology ◽

10.1071/pp96114 ◽

1998 ◽

Vol 25 (1) ◽

pp. 13 ◽

Cited By ~ 25

Author(s):

P.J. Stone ◽

M.E. Nicolas

Keyword(s):

Heat Treatment ◽

Heat Stress ◽

High Temperature ◽

Heat Tolerance ◽

Grain Filling ◽

Protein Accumulation ◽

Tolerant Variety ◽

Heat Tolerant ◽

Very High ◽

Individual Kernel

Two varieties of wheat differing in heat tolerance were exposed to very high temperature (40/19°C day/night) for periods of 1–10 days duration. Responses of grain dry matter, water and fractional protein accumulation to high temperature were monitored throughout grain filling in the heat- sensitive variety, and at maturity only in the heat-tolerant variety. Results are compared with controls maintained at 21/16°C day/night. As little as 1 day of heat treatment reduced kernel mass by 14% in the heat-sensitive variety (Oxley), but by only 5% in the heat-tolerant variety (Egret). In both varieties, the reduction of individual kernel mass due to high temperature increased linearly with increased duration of heat treatment, such that after the first day of heat stress, each additional day of treatment reduced mature individual kernel mass by a further 1.6%. For a given duration of heat treatment, the difference in response of the two varieties was constant (9%), indicating that the varietal difference in heat tolerance was maintained for both brief and extended periods of very high temperature. Responses of grain water content and fractional protein accumulation to duration of heat stress are discussed.

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Breed and seasonal variation in thermoregulatory paramters of some selected Nigerian indigenous cattle

Nigerian Journal of Animal Production ◽

10.51791/njap.v47i6.2867 ◽

2021 ◽

Vol 47 (6) ◽

pp. 18-31

Author(s):

H. Y. Abbaya ◽

I. I. Adedibu ◽

M. Kabir ◽

A. O. Iyiola-Tunji

Keyword(s):

Heat Stress ◽

Seasonal Variation ◽

Respiratory Rate ◽

Pulse Rate ◽

Heat Tolerance ◽

Rectal Temperature ◽

Indigenous Cattle ◽

Fréquence Cardiaque ◽

Stress Thermique ◽

Breed Differences

The study was conducted to evaluate breed differences in thermoregulatory parameters of four Nigerian indigenous breeds of cattle over two seasons (late rainy and late dry). Data on thermoregulatory parameters (rectal temperature, respiratory rate, pulse rate and Heat Tolerance Coefficient) of eighty (80) cattle, comprising 20 each of Bunaji, Rahaji, Bokoloji and Adamawa Gudali were obtained and subjected to analysis of variance of SAS software. In the pooled breed variation, breed influenced (p<0.05) all the parameters measured. Bunaji recorded the highest rectal temperature (37.92oC) in all the seasons of measurement. Respiratory rate and Heat tolerance coefficient were highest in Bokoloji while the least were in Bunaji and Adamawa Gudali. Season significantly (p<0.05) affected thermoregulatory parameters measured except (p>0.05) rectal temperature. The highest recorded values of respiratory rate (27.85 beat/min), Pulse rate (27.62breaths/min) and HTC (2.19) were in the late dry season. The effect of interaction between breed and season on thermoregulatory parameters significantly affected (p<0.05) all the thermoregulatory parameters measured. It was concluded that Bokoloji and Bunaji breeds of indigenous cattle are more reactive to Heat stress than Rahaji and Adamawa Gudali even though this could vary with seasons of the year as seen in the interaction between breed and season in this study. L'étude a été menée pour évaluer les différences entre les races dans les paramètres thermorégulateurs de quatre races indigènes de bétail nigérianes sur deux saisons (pluvieuse tardive et sèche tardive). Des données sur les paramètres thermorégulateurs (température rectale, fréquence respiratoire, fréquence du pouls et coefficient de tolérance à la chaleur) de quatre-vingts (80) bovins, comprenant 20 de chacun de Bunaji, Rahaji, Bokoloji et Adamawa Gudali ont été obtenues et soumises à l'analyse de variance du logiciel 'SAS'. Dans la variation de race combinée, la race a influencé (p <0,05) tous les paramètres mesurés. Bunaji a enregistré la température rectale la plus élevée (37,920 ° C) de toutes les saisons de mesure. La fréquence respiratoire et le coefficient de tolérance à la chaleur étaient les plus élevés à Bokoloji tandis que les plus faibles étaient à Bunaji et à Adamawa Gudali. La saison a affecté significativement (p <0,05) les paramètres thermorégulateurs mesurés sauf (p> 0,05) la température rectale. Les valeurs les plus élevées enregistrées de la fréquence respiratoire étaient (27,85 battements / min), la fréquence cardiaque (27,62 respirations / min) et le 'HTC' (2,19) étaient à la fin de la saison sèche.L'effet de l'interaction entre la race et la saison sur les paramètres thermorégulateurs était significativement affecté (p <0,05) tous les paramètres thermorégulateurs mesurés. Il a été conclu que les races Bokoloji et Bunaji de bovins indigènes sont plus réactives au stress thermique que Rahaji et Adamawa Gudali, même si cela peut varier avec les saisons de l'année, comme le montre l'interaction entre la race et la saison dans cette étude.

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Heat-tolerant hot pepper exhibits constant photosynthesis via increased transpiration rate, high proline content and fast recovery in heat stress condition

Scientific Reports ◽

10.1038/s41598-021-93697-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sherzod Nigmatullayevich Rajametov ◽

Eun Young Yang ◽

Myeong Cheoul Cho ◽

Soo Young Chae ◽

Hyo Bong Jeong ◽

...

Keyword(s):

Heat Treatment ◽

Heat Stress ◽

Heat Tolerance ◽

Transpiration Rate ◽

Stress Condition ◽

Proline Content ◽

Hot Pepper ◽

Fast Recovery ◽

Heat Stress Condition ◽

Heat Tolerant

AbstractUnderstanding the mechanism for heat tolerance is important for the hot pepper breeding program to develop heat-tolerant cultivars in changing climate. This study was conducted to investigate physiological and biochemical parameters related to heat tolerance and to determine leaf heat damage levels critical for selecting heat-tolerant genotypes. Seedlings of two commercial cultivars, heat-tolerant ‘NW Bigarim’ (NB) and susceptible ‘Chyung Yang’ (CY), were grown in 42 °C for ten days. Photosynthesis, electrolyte conductivity, proline content were measured among seedlings during heat treatment. Photosynthetic rate was significantly reduced in ‘CY’ but not in ‘NB’ seedlings in 42 °C. Stomatal conductivity and transpiration rate was significantly higher in ‘NB’ than ‘CY’. Proline content was also significantly higher in ‘NB’. After heat treatment, leaf heat damages were determined as 0, 25, 50 and 75% and plants with different leaf heat damages were moved to a glasshouse (30–32/22–24 °C in day/night). The growth and developmental parameters were investigated until 70 days. ‘NB’ was significantly affected by leaf heat damages only in fruit yield while ‘CY’ was in fruit set, number and yield. ‘NB’ showed fast recovery after heat stress compared to ‘CY’. These results suggest that constant photosynthetic rate via increased transpiration rate as well as high proline content in heat stress condition confer faster recovery from heat damage of heat-tolerant cultivars in seedlings stages.

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Breed Differences in Heat Tolerance of Day-Old Baby Chicks

Poultry Science ◽

10.3382/ps.0300625a ◽

1951 ◽

Vol 30 (4) ◽

pp. 625-627 ◽

Cited By ~ 9

Author(s):

Wilbor O. Wilson ◽

Theodore H. Plaister

Keyword(s):

Heat Tolerance ◽

Breed Differences

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Effect of Timing of Heat Stress During Grain Filling on Two Wheat Varieties Differing in Heat Tolerance. II. Fractional Protein Accumulation

Functional Plant Biology ◽

10.1071/pp9960739 ◽

1996 ◽

Vol 23 (6) ◽

pp. 739 ◽

Cited By ~ 29

Author(s):

PJ Stone ◽

ME Nicolas

Keyword(s):

Heat Stress ◽

High Temperature ◽

Grain Growth ◽

Heat Tolerance ◽

Grain Filling ◽

Size Exclusion ◽

Protein Accumulation ◽

Wheat Varieties ◽

Grain Filling Period ◽

Very High

Short periods of very high temperature (> 35�C) are common during the grain filling period of wheat, and can significantly alter mature protein composition and consequently grain quality. This study was designed to determine the stage of grain growth at which fractional protein accumulation is most sensitive to a short heat stress, and to examine whether varietal differences in heat tolerance are expressed consistently throughout the grain filling period. Two varieties of wheat differing in heat tolerance (cvv. Egret and Oxley, tolerant and sensitive, respectively) were exposed to a short (5 day) period of very high temperature (40�C max, for 6 h each day) at 5-day intervals throughout grain filling, from 15 to 50 days after anthesis. Grain samples were taken throughout grain growth and analysed for protein content and composition (albumin/globulin, monomer, SDS-soluble polymer and SDS-insoluble polymer) using size-exclusion high-performance liquid chromatography. The timing of heat stress exerted a significant influence on the accumulation of total wheat protein and its fractions, and protein fractions differed in their responses to the timing of heat stress. Furthermore, wheat genotype influenced both the sensitivity of fractional protein accumulation to heat stress and the stage during grain filling at which maximum sensitivity to heat stress occurred.

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Heat-tolerant Hot Pepper Exhibits Constant Photosynthesis Via Increased 4 Transpiration Rate, High Proline Content and Fast Recovery in Heat Stress 5 Condition

10.20944/preprints202107.0348.v1 ◽

2021 ◽

Author(s):

Sherzod Rajametov ◽

Eun Young Yang ◽

Myeong Cheoul Cho ◽

Soo Young Chae ◽

Hyo Bong Jeong ◽

...

Keyword(s):

Heat Treatment ◽

Heat Stress ◽

Photosynthetic Rate ◽

Heat Tolerance ◽

Transpiration Rate ◽

Proline Content ◽

Hot Pepper ◽

Fast Recovery ◽

Heat Damage ◽

Heat Tolerant

Understanding the mechanism for heat tolerance is important for the hot pepper breeding program to develop heat-tolerant cultivars in changing climate. This study was conducted to investigate physiological and biochemical parameters related to heat tolerance and to determine leaf heat damage levels critical for selecting heat-tolerant genotypes. Seedlings of two commercial cultivars, heat-tolerant ‘NW Bigarim’ (NB) and susceptible ‘Chyung Yang’ (CY), were grown in 42 °C for ten days. Photosynthesis, electrolyte conductivity, proline content were measured among seedlings during heat treatment. Photosynthetic rate was significantly reduced in ‘CY’ but not in ‘NB’ seedlings in 42 °C. Stomatal conductivity and transpiration rate was significantly higher in ‘NB’ than ‘CY’. Proline content was also significantly higher in ‘NB’. After heat treatment, leaf heat damages were determined as 0, 25, 50 and 75% and plants with different leaf heat damages were moved to a glasshouse (30–32/22–24 °C in day/night). The growth and developmental parameters were investigated until 70 days. ‘NB’ was significantly affected by leaf heat damages only in fruit yield while ‘CY’ was in fruit set, number and yield. ‘NB’ showed fast recovery after heat stress compared to ‘CY’. These results suggest that constant photosynthetic rate via increased transpiration rate as well as high proline content in heat stress condition confer faster recovery from heat damage of heat-tolerant cultivars in seedlings stages.

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Effect of Heat Treatment on Physiological and Recovery Growth Status of Two Tomato Cultivars With Different Heat Susceptibility

10.20944/preprints202102.0122.v1 ◽

2021 ◽

Author(s):

Sherzod Nigmatullayevich Rajametov ◽

Eun Young Yang ◽

Hyo Bong Jeong ◽

Myeong Cheoul Cho ◽

Soo-Young Chae ◽

...

Keyword(s):

Heat Stress ◽

High Temperature ◽

Stress Tolerance ◽

Heat Tolerance ◽

Fruit Set ◽

Fruit Size ◽

Seedling Stage ◽

Screening Methods ◽

Tomato Cultivars ◽

Heat Tolerant

High temperature seriously effects on plant vegetative and reproductive development and reduces productivity of plants, while to increase crop yield is the main target in most crop heat stress tolerance improvement breeding programs, not just survival, under high temperature. Our aim was to compare temperature stress tolerance in two commercial tomato cultivars “Dafnis” (big fruit size) and “Minichal” (cherry fruit size) to develop early screening methods and find out survival rate and physiological responses of tomato cultivars on high temperature (40°C and within 70% RH, day/night) in 4-5 true leaf seedling stage- (4LS) and identifies the linkage of heat tolerance with fruit set and leaf heat damage rates (LHD) in seedling stage with subsequent vegetative traits at recovery. Results showed that heat stress significantly affected on physiological-chemical and vegetative parameters of seedlings regardless of tomato cultivars. Survival and the threshold level of high temperature tolerance in the seedlings of cv. “Dafnis” and “Minichal” were identified on days 7 and 9, respectively. Our findings revealed that photosynthesis (PN, Gs, Ci, Tr) parameters were increased and CHL content persisted steady value in cv. “Minichal” during heat stress period, however EC and RPL rates were lower than cv. “Dafnis”. Heat stress reduced the SFW in both cultivars in seedling stage, but PH and RFW were significantly decreased in the heat tolerant cv. “Minichal”, whereas this parameters were not significantly ranged in the heat susceptible cv. “Dafnis”. Additionally, there no found linkage between vegetative parameters with decreasing of PN and CHL rates during HT of seedlings. In plants of cv. “Minichal” with LHD-25, 50 and 75% were no found significant differences in PH, whereas in cv. “Dafnis” significant differences were determined in plants with LHD-75%, and the significant differences in rates of SFW and RFW were observed in plants of cv. “Dafnis” having LHD-75% for 28 days of recovery at NT condition. Taken together, we concluded that heat stress affected on physiological parameters regardless of tolerance level, and to identify heat tolerant genotype in tomato breeding program, screening and selection genotypes have to be evaluated at the vegetative and reproductive stages with consideration fruit size types. Since we could not find linkage between heat tolerances in seedling stage with fruit set at the reproductive stage and fruit set cannot be used as a general predictor of heat tolerance.

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Assessment of Heat-tolerance Potential in QTL Introgressed Lines of Hybrid Rice Restorer, KMR-3R through PS-II Efficiency

International Journal of Environment and Climate Change ◽

10.9734/ijecc/2021/v11i1130540 ◽

2021 ◽

pp. 258-266

Author(s):

V. Jaldhani ◽

D. Sanjeeva Rao ◽

P. Beulah ◽

B. Srikanth ◽

P. R. Rao ◽

...

Keyword(s):

High Temperature ◽

Quantum Yield ◽

Temperature Stress ◽

Heat Tolerance ◽

Photosynthetic Apparatus ◽

High Temperature Stress ◽

Maximum Efficiency ◽

Photochemical Quenching ◽

Psii Photochemistry ◽

Heat Tolerant

Aims: To assess heat-induced PSII damage and efficiency in eight promising backcross introgression lines (BC2F6) of KMR-3R/N22 possessing qHTSF1.1 and qHTSF4.1. Study Design: Randomized Complete Block Design (RCBD) with three replications. Place and Duration of Study: ICAR-Indian Institute of Rice Research, Hyderabad India during wet/rainy (Kharif) season 2018. Methodology: Eight ILs (BC2F6) and parents were evaluated for heat tolerance. The high- temperature stress was imposed by enclosing the crop with a poly cover tent (Polyhouse) just before the anthesis stage. The fluorescence parameters viz., maximum efficiency of PSII photochemistry (Fv/Fm), Electron transport rate (ETR), effective PSII quantum yield (ΦPSII), coefficient of photochemical quenching (qP) and coefficient of non-photochemical quenching (qN) were measured under ambient and high-temperature stress. Results: The heat-tolerance potential of ILs was assessed in terms of PSII activity. The results indicated that significant differences were observed between treatments (T), genotypes (G) and the interaction between T × G. The physiological basis of introgressed QTLs controls the spikelet fertility by maintaining the productive and adaptive strategies in heat-tolerant QTL introgressed lines with stable photosynthetic apparatus (PSII) under high-temperature stress. Conclusion: The Fv/Fm ratio denotes the maximum quantum yield of PSII. The heat-tolerant QTL introgressed lines exhibited stable photosynthetic apparatus (PSII) and noted better performance under high-temperature stress. They may be used as donors for fluorescence traits in breeding rice for high-temperature tolerance.

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