Impact of lighting regimes on reproductive performance and sperm ultrastructure in rabbit bucks under very severe heat stress conditions

Abstract. This study was conducted to determine the effects of methionine (Met) supplementation on productive and reproductive performance, immune response and antioxidant status in breeder quails reared under heat stress (HS). A total of 125 breeder quails were divided into five groups. One group was kept in an environmentally controlled room at 22 ∘C and considered as thermoneutral, and four groups were kept at 34 ∘C and fed a basal diet (heat stressed) or a basal diet with Met concentrations 1.15, 1.30 and 1.45 times the quail requirements per NRC (1994) recommendations. HS decreased egg production in birds fed the basal diet (P < 0.05). Higher feed intake (P < 0.05), egg production (P < 0.05), improved feed efficiency (P < 0.05) and Haugh unit and hatchability variables (P < 0.05) occurred in Met supplemented groups. Birds receiving Met under HS had higher maternal serum IgG, egg yolk IgY and offspring serum IgG (mg mL−1). Quails receiving the Met supplementation diets exhibited higher (P < 0.05) plasma levels and liver activity of superoxide dismutase, catalase and glutathione peroxidase as well as lower (P < 0.05) plasma and liver levels of malondialdehyde compared to the HS group fed the basal diet. All breeder quails receiving the Met supplement had lower (P < 0.05) heterophil and H∕L ratios as well as higher (P < 0.05) lymphocytes than quails fed the basal diet under the same stress conditions. Our results suggest that dietary supplementation with Met could improve the performance, immunity and antioxidant status of quails by reducing the negative effects of HS.

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Productive and reproductive performance, behavior and physiology of cattle under heat stress conditions

Journal of Animal Behaviour and Biometeorology ◽

10.26667/2318-1265jabb.v5n3p91-96 ◽

2017 ◽

Vol 5 (3) ◽

pp. 91-96 ◽

Cited By ~ 4

Author(s):

José Romero Alexandre Alves ◽

◽

Thiago Antunes Adriano de Andrade ◽

Daniel de Medeiros Assis ◽

Thyago Araújo Gurjão ◽

...

Keyword(s):

Heat Stress ◽

Reproductive Performance ◽

Stress Conditions ◽

Performance Behavior

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Reproductive efficiency of Pelibuey and Romanov × Pelibuey ewes synchronized with synthetic progesterone and low doses of PMSG under a hot environment

Czech Journal of Animal Science ◽

10.17221/7089-cjas ◽

2013 ◽

Vol 58 (No. 12) ◽

pp. 546-553 ◽

Cited By ~ 3

Author(s):

U. Macías-Cruz ◽

J.L. Ponce-Covarrubias ◽

F.D. Álvarez-Valenzuela ◽

A. Correa-Calderón ◽

C.A. Meza-Herrera ◽

...

Keyword(s):

Heat Stress ◽

Reproductive Performance ◽

Stress Conditions ◽

Reproductive Efficiency ◽

Gestation Length ◽

Low Doses ◽

Hot Environment ◽

Pregnant Mare Serum Gonadotropin ◽

Genotype Interaction ◽

Serum Gonadotropin

Thirty-nine multiparous ewes (19 Pelibuey and 20 Romanov × Pelibuey) treated with fluorogestone acetate impregnated intravaginal sponges were used to evaluate the effects of low pregnant mare serum gonadotropin (PMSG) doses and genotype on their reproductive efficiency under heat stress conditions. The sponge treatment lasted for 12 days, and 24 h before sponge removal, ewes of each genotype were injected with 140 or 280 IU of PMSG. Ewes showing estrus were naturally mated twice. Reproductive performance was not affected (P > 0.05) by the dose × genotype interaction. All treated ewes presented estrus signs within a 48-h period after sponge removal. Shorter (P < 0.05) estrus interval and higher (P < 0.05) fecundity were observed in ewes treated with 280 IU of PMSG compared to those treated with 140 IU. Pelibuey ewes exhibited shorter (P < 0.01) estrus interval and greater (P < 0.01) fertility as compared with Romanov × Pelibuey ewes. The response to estrus, gestation length, prolificacy, and percentage of single and multiple lambing were not affected (P >  0.05) by dose or genotype. In conclusion, under heat stress conditions, low PMSG doses as 140 or 280 IU can be used to successfully induce and/or synchronize the estrus in Pelibuey ewes and their crosses with Romanov, regardless of reduced fertility observed in crossed Pelibuey ewes. If a more predictable and compact estrus is required, administration of 280 IU of PMSG is recommended.

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The Effect of Personal Cooling Systems on Performance under Heat Stress

Proceedings of the Human Factors Society Annual Meeting ◽

10.1177/154193128202600205 ◽

1982 ◽

Vol 26 (2) ◽

pp. 128-131

Author(s):

Dan Zakay ◽

Yair Shapiro ◽

Yoram Epstein ◽

Shay Bril

Keyword(s):

Heat Stress ◽

Future Development ◽

Cooling System ◽

Stress Conditions ◽

Cooling Systems ◽

The Future ◽

Severe Heat Stress ◽

Fan Cooling ◽

Personal Cooling

The effect of personal cooling systems on performance under heat stress was examined. Nine subjects were tested in severe heat stress conditions with seven types of personal cooling systems. It was found that, excluding the fan cooling system, all personal cooling systems enabled better performance as compared to performance under heat stress conditions without such a system. However, differences on several parameters among the various cooling systems were found. These differences are analyzed and the future development of such systems is discussed.

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Melatonin Treatment at Dry-off Improves Reproductive Performance Postpartum in High-producing Dairy Cows under Heat Stress Conditions

Reproduction in Domestic Animals ◽

10.1111/rda.12128 ◽

2012 ◽

Vol 48 (4) ◽

pp. 577-583 ◽

Cited By ~ 23

Author(s):

I Garcia-Ispierto ◽

A Abdelfatah ◽

F López-Gatius

Keyword(s):

Heat Stress ◽

Dairy Cows ◽

Reproductive Performance ◽

Stress Conditions ◽

Melatonin Treatment

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Protein synthesis and protein phosphorylation during heat stress, recovery, and adaptation.

The Journal of Cell Biology ◽

10.1083/jcb.109.4.1467 ◽

1989 ◽

Vol 109 (4) ◽

pp. 1467-1481 ◽

Cited By ~ 132

Author(s):

R F Duncan ◽

J W Hershey

Keyword(s):

Protein Synthesis ◽

Heat Stress ◽

Stress Proteins ◽

Elevated Temperatures ◽

Stress Conditions ◽

Initiation Factor ◽

Mild Heat ◽

Inhibition Of Protein Synthesis ◽

Adaptation Response ◽

Severe Heat Stress

Incubating cells at elevated temperatures causes an inhibition of protein synthesis. Mild heat stress at 41-42 degrees C inhibits the fraction of active, polysomal ribosomes from greater than 60% (preheating) to less than 30%. A return to 37 degrees C leads to an increase in protein synthesis, termed "recovery." Continuous incubation at 41-42 degrees C also leads to a gradual restoration of protein synthesis (greater than 70% of ribosomes reactivated by 2-4 h), termed "adaptation". Protein synthesis inhibition and reactivation is prestressed, recovered cells that contain elevated levels of the heat stress proteins occur to the same extent and at the same rate as in "naive" cells. The adaptation response requires transcription of new RNA whereas recovery does not. A large number of phosphorylation changes are induced by severe heat stress and occur with kinetics similar to the inhibition of protein synthesis. These include phosphorylation of eukaryotic protein synthesis initiation factor (eIF)-2 alpha and dephosphorylation of eIF-4B and eIF-4Fp25 (eIF-4E). However, the extent to which the modification occurs is proportional to the severity of the stress, and, under mild (41-42 degrees C) heat stress conditions, these initiation factor phosphorylation changes do not occur. Similarly, under conditions of severe heat stress eIF-2 alpha and eIF-4B frequently recover to their prestress phosphorylation state before the recovery of protein synthesis. eIF-4E dephosphorylation likewise does not occur under mild heat stress conditions. Therefore, these changes in phosphorylation states, which are thought to be sufficient cause, are not necessary for the inhibition of protein synthesis observed.

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IMPACT OF USING CHAMOMILE FLOWER AS A FEED ADDITIVE ON REPRODUCTIVE PERFORMANCE AND PHYSIOLOGICAL RESPONSES OF FARAFRA EWES DURING HEAT STRESS CONDITIONS

Egyptian Journal of Nutrition and Feeds ◽

10.21608/ejnf.2018.75758 ◽

2018 ◽

Vol 21 (3) ◽

pp. 635-643

Author(s):

A. Saleh ◽

G. Abozed

Keyword(s):

Heat Stress ◽

Reproductive Performance ◽

Physiological Responses ◽

Stress Conditions ◽

Feed Additive ◽

Chamomile Flower

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Exploring Morpho-Physiological Variation for Heat Stress Tolerance in Tomato

Plants ◽

10.3390/plants10020347 ◽

2021 ◽

Vol 10 (2) ◽

pp. 347

Author(s):

Samikshya Bhattarai ◽

Joshua Harvey ◽

Desire Djidonou ◽

Daniel Leskovar

Keyword(s):

Heat Stress ◽

Chlorophyll Fluorescence ◽

Open Field ◽

Electrolyte Leakage ◽

Leaf Gas Exchange ◽

Total Yield ◽

Stress Conditions ◽

Heat Injury ◽

Injury Index ◽

Heat Tolerant

Texas tomato production is vulnerable to extreme heat in the spring-summer cropping period, which is exacerbated by the lack of superior genetic materials that can perform well in such environments. There is a dire need for selecting superior varieties that can adapt to warm environments and exhibit high yield stability under heat stress conditions. This research aimed at identifying heat-tolerant varieties under heat-stress conditions in controlled and open-field environments and was carried out in three stages. For the first experiment, 43 varieties were screened based on yield responses in natural open-field environment. From those, 18 varieties were chosen and exposed to control (greenhouse: 26/20 °C) and constant heat-stress (growth-chamber: 34/24 °C) conditions for three months. Measurements were done for chlorophyll fluorescence, chlorophyll content (SPAD), plant height, stem diameter and heat injury index (HII). The last experiment was conducted in an open field with a pool of varieties selected from the first and second experiments. Leaf gas exchange, leaf temperature, chlorophyll fluorescence, SPAD value, electrolyte leakage, heat injury index and yield were assessed. From the combined studies, we concluded that heat-tolerant genotypes selected by using chlorophyll fluorescence and HII in controlled heat-stress conditions also exhibited heat-tolerance in open-field environments. Electrolyte leakage and HII best distinguished tomato varieties in open-field environments as plants with low electrolyte leakage and HII had higher total yield. 'Heat Master,' 'New Girl,' 'HM-1823,' 'Rally,' 'Valley Girl,' 'Celebrity,' and 'Tribeca' were identified as high heat-tolerant varieties. Through trait correlation analysis we provide a better understanding of which traits could be useful for screening and breeding other heat-tolerant tomato varieties.

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