Foetal stunting in sheep: 2. The effects of high ambient temperature during gestation on wool follicle development in the foetal lamb

1976 ◽  
Vol 86 (3) ◽  
pp. 581-585 ◽  
Author(s):  
G. A. Cartwright ◽  
C. J. Thwaites
Keyword(s):  
High Temperature ◽  
Ambient Temperature ◽  
Feed Intake ◽  
High Ambient Temperature ◽  
Follicle Development ◽  
Apparent Effect ◽  
New Born ◽  
Wool Growth ◽  
Wool Follicle ◽  
Foetal Lamb

SummaryHotroom treatment of ewes during the last two-thirds of gestation resulted in the birth of lambs which were significantly lighter than lambs born to nutritionallydeprived ewes. Neither high temperature nor undernutrition had significant effect on the density of either primary or immature secondary wool follicles, but the total number of mature secondary follicles tended to decline in the lambs from unheated ewes as the level of nutrition declined, and was significantly reduced by a further 30 % in the hotroom group.In a second experiment, heated and unheated ewes fed to appetite were compared with unheated ewes pair-fed to the hotroom level of feed intake. High temperature had no apparent effect on maternal wool growth, but did reduce total wool follicle number in new-born lambs by approximately 50%. This effect was most marked with respect to mature secondary follicles (only 18% of unheated mean), less so in immature secondaries (56% of unheated mean), and barely discernible amongst primary follicles (93% of unheated mean). None of the differences in follicle numbers between the two unheated groups was significant.The results suggest that the effects of high temperature on wool follicle development in the sheep foetus are akin to those of extreme undernutrition.

The effect of ambient temperature on feed intake and diet selection in growing lambs

1992 ◽  
Vol 1992 ◽  
pp. 166-166
Author(s):  
M.R. Cropper ◽  
D.P. Poppi
Keyword(s):  
Ambient Temperature ◽  
Protein Content ◽  
Feed Intake ◽  
Free Choice ◽  
Environmental Temperature ◽  
Diet Selection ◽  
High Ambient Temperature

Lambs are known to change their feed intake in relation to environmental temperature (Blaxter, 1962). However, their ability to select a non-limiting diet, when free-choice fed, has only been investigated in a thermoneutral environment (Cropper, 1987). The aim of this experiment was to test the idea that, at low and high ambient temperature, (a) feed intake would increase in the cold and decrease in the hot, relative to a thermoneutral control, and that (b) the protein content of the diet selected would be lower and higher respectively.

Effects of weather and parasitic insects on behavior and group dynamics of caribou of the Delta Herd, Alaska

1997 ◽  
Vol 75 (10) ◽  
pp. 1659-1670 ◽  
Author(s):  
Frank M. Mörschel ◽  
David R. Klein
Keyword(s):  
High Temperature ◽  
Ambient Temperature ◽  
Group Dynamics ◽  
Rangifer Tarandus ◽  
High Ambient Temperature ◽  
Alaska Range ◽  
North Central ◽  
Insect Abundance ◽  
Rates Of Change ◽  
The North

The influence of weather and parasitic insects on the behavior and group dynamics of caribou (Rangifer tarandus) of the Delta Herd in the north-central Alaska Range was investigated. Data on weather, insect abundance, and caribou behavior were collected during summer in 1994 and 1995. High ambient temperature had the greatest influence on activity budgets and rates of change in activity of caribou. In the insect season, rates of activity changes and standing increased and feeding decreased with high temperature. Rates of activity changes and moving increased and feeding decreased with high temperature, even in the absence of insects. Caribou decreased feeding and increased standing in the presence of oestrid flies, and increased the rate of activity changes in the presence of mosquitoes and oestrid flies. Weather, especially high temperature, and parasitic insects, particularly oestrid flies, affected caribou mainly by decreasing foraging opportunities and increasing energy-expending activities.

scholarly journals VIL1, a Polycomb-associated protein, modulates high ambient temperature response via H3K27me3 and H2A.Z in Arabidopsis thaliana

2020 ◽  
Author(s):  
Yogendra Bordiya ◽  
Junghyun Kim ◽  
Yanpeng Xi ◽  
Dong-Hwan Kim ◽  
Youngjae Pyo ◽  
...  
Keyword(s):  
Arabidopsis Thaliana ◽  
High Temperature ◽  
Ambient Temperature ◽  
Epigenetic Regulation ◽  
Temperature Response ◽  
High Ambient Temperature ◽  
Rna Seq ◽  
Wild Type ◽  
Phd Finger ◽  
Finger Protein

AbstractAdapting to the everchanging environment is key to a successful life for an organism. Eukaryotes reprogram their transcriptome in order to adapt to an unfavorable environment. To achieve this reprogramming, plants and animals employ multiple responses including epigenetic regulation. In the search for mutations compromised in high ambient temperature response, we found that VIL1, a PHD finger protein displays aberrant development at high temperature. RNA-seq analysis shows that vil1 fails to downregulate heat suppressed genes. H2A.Z ChIP-seq showed that unlike wild type, vil1 fails to evict H2A.Z from heat responsive genes. We also found that vil1 suppresses constitutive thermo-morphogenic phenotype of arp6. Supporting this phenotype, RNA-seq analysis revealed that constitutive heat responsive transcriptome of arp6 reverted back to the wild-type levels in arp6vil1. This observation suggests an antagonistic relationship between VIL1 and ARP6. We found that this antagonism can be explained in part by interaction between H3K27me3 and H2A.Z.

scholarly journals Effects of High Ambient Temperature and Bypass Protein Supplementation on Performance of Crossbred Lambs

2019 ◽  
Vol 2 (1) ◽  
pp. 78
Author(s):  
Dahlanuddin Dahlanuddin ◽  
C.J. Thwaites ◽  
J.V. Nolan
Keyword(s):  
Weight Gain ◽  
High Temperature ◽  
Ambient Temperature ◽  
Cottonseed Meal ◽  
Dry Matter ◽  
Control Diet ◽  
Live Weight ◽  
High Ambient Temperature ◽  
Dry Matter Intake ◽  
Ad Libitum

The objective of this experiment was to study the effect of dietary supplementation with a source ofbypass protein (cottonseed meal, CSM) on the performance of growing crossbred wethers fed lowdigestibility roughage at high ambient temperature. Sixteen unshorn Border Leicester x Merino lambsaged 6 months and weighing 24.90.37 kg were allocated into a 2x2 factorial design (2 diets and 2ambient temperatures). Each group was fed either wheaten chaff + 2% urea ad libitum or wheaten chaff +1% urea ad libitum + 100g/d cottonseed meal. The results show that respiration rate and rectal temperaturewere significantly affected by ambient temperature (P<0.01), but not by diet. Total dry matter intake wassignificantly higher (P<0.01) at lower temperature than at high temperature, and significantly higher(P=0.04) on the supplemented diet than on the control diet. Water intake tended (P=0.06) to be higher onthe CSM+ diet than on the control diet, and was significantly at greater (P<0.01) high ambient temperaturethan at low temperature. The concentration of NH3-N in the rumen fluid (ranged from 310±17 to 413±20mg N/L) did not differ significantly either between diets or ambient temperatures. Blood plasma ureanitrogen concentration was significantly higher in sheep on the control diet than in those on thesupplemented diet, and at low than high temperature. The organic matter digestibility was not significantlyaffected by temperature and diet. The rate of live weight gain was significantly (P<0.01) reduced by highambient temperature and the interaction between diet and temperature was significant (P<0.01). At lowtemperature, lambs on the supplemented diet grew significantly faster than those on the control diet, butnot at high temperature. In conclusion, high ambient temperature increases respiration rate, rectaltemperature and water intake but reduces dry matter intake and live weight gain. Supplementation with100 g/d of cottonseed meal could not outweigh the depressing effects of constant high ambienttemperature and humidity imposed in this experiment.

scholarly journals Comparison of linear functions to estimate growth performance and feed intake variations pattern in growing and finishing pigs in high ambient temperature

2019 ◽  
Vol 44 (2) ◽  
pp. 177
Author(s):  
N. Lee ◽  
J. W. Choi ◽  
H. S. Ko ◽  
S. J. Ohh ◽  
Y. H. Kim ◽  
...  
Keyword(s):  
Ambient Temperature ◽  
Feed Intake ◽  
Mixed Model ◽  
Average Daily Gain ◽  
High Ambient Temperature ◽  
Linear Functions ◽  
Effect Of Temperature ◽  
Feed Ratio ◽  
Finishing Pigs ◽  
Linear Relationships

High ambient temperature (AT) is a major constraint on efficiency of farming in pig production. Results of reported studies assessing the influences of high AT on pig performance are highly variable, particularly in pigs with different body weight (BW). Therefore, a meta-analysis from ISI Web of Science and PubMed was operated to explain variations of average daily feed intake (ADFI) and average daily gain (ADG) in the reports across literatures during high AT in growing or finishing pigs. Pigs were divided to three BW categories as LOW (46 to 65 kg), MED (65< to 85 kg), and HGH (85< kg). The significant effect of AT on ADG were observed in LOW, MED, and HGH categories. The analysis of variance (ANOVA) for multiple linear regression shows significance of linear relationships between both ADG and ADFI, and AT and BW as: ADGLOW= 1260-19.9*AT+2.09*BW, ADGMED= 1546-22.5*AT-0.88*W, ADGHGH= 1893-31.9*AT-2.40*BW, ADFILOW= 1756-35.0*AT+24.6*BW, ADFIMED= 2793-49.6*AT+12.5*BW, and ADFIHGH= 4172-59.0*AT+0.74*BW. The significant effect of temperature on gain to feed ratio (G:F) was observed in LOW and HGH categories. The ANOVA for multiple regression revealed evidence on high significance of linear relationships between G:F and AT: G:FLOW =0.80+0.02*AT+0.02*BW, G:FMED= 0.95+0.02*AT+0.02*BW, and G:FHGH= 0.78+0.05*AT+0.01*BW. The overall results of mixed model analysis show that the significant interaction between BW and AT means that pigs in heavier category have lower G:F when temperature increases. In conclusion, high AT linearly decrease the ADG, ADFI, and G:F of growing and finishing pigs.

scholarly journals A Step Toward High Temperature Intelligent Power Modules Using 1.5kV SiC-BJT

2010 ◽  
Vol 645-648 ◽  
pp. 1155-1158 ◽  
Author(s):  
Dominique Tournier ◽  
Pascal Bevilacqua ◽  
Pierre Brosselard ◽  
Dominique Planson
Keyword(s):  
High Temperature ◽  
Ambient Temperature ◽  
Preliminary Analysis ◽  
High Efficiency ◽  
High Ambient Temperature ◽  
Large Power ◽  
Turn On ◽  
Power Modules ◽  
Functional Blocks ◽  
Looking Back

Looking back to the development of inverters using SiC switches, it appears that SiC devices do not behave like their silicon counterparts. Their ability to operate at high temperature makes them attractive. Developing drivers suitable for 200 °C operation is not straightforward. In a perspective of high integration and large power density, it is wise to consider a monolithic integration of the driver parts for the sake of reliability. Silicon is not suitable for high ambient temperature; silicon-oninsulator offers better performances and presents industrial perspectives. The paper focuses on a SiC BJT driver: it processes logical orders from outside, drives adequately the BJT to turn it either on or off, monitors the turn-off and turn-on state of the device, and acts accordingly to prevent failure. SiC BJT imposes specific performances different from the well known ones of SiC JFET or MOSFET. The paper addresses a preliminary analysis of a SOI driver, anticipating the behavior of SiC-BJT and the change in behavior at high temperature. A discret driver has been designed and fabricated. Elementary functional blocks have been validated, and a BJT converter successfully operated at high temperature with high efficiency ( = 88%).

Loss of potential young in the ewe due to high ambient temperature

1961 ◽  
Vol 16 (2) ◽  
pp. 253-256 ◽  
Author(s):  
C. W. Alliston ◽  
Gene E. Egli ◽  
L. C. Ulberg
Keyword(s):  
High Temperature ◽  
Embryonic Development ◽  
Ambient Temperature ◽  
Reproductive Performance ◽  
Fertilization Rate ◽  
High Ambient Temperature ◽  
Summer Temperatures ◽  
Higher Temperature

Embryonic development and other measures of reproductive performance were compared for 3 years in sheep maintained at 65°F, at prevailing summer temperatures, and at a constant, high temperature (92°F). The concentration and motility of the sperm and the fertility of the semen from control rams declined during periods of high temperature. Fertilization rate was lowered when rams were exposed to high prevailing atmospheric temperatures or ewes to a constant high temperature. A higher percentage of morphologically abnormal ova was recovered from ewes subjected to the higher temperatures. The stages of embryonic development indicated that, in ewes at the higher temperature, a loss of potential young occurs by a cessation of development during cleavage. Submitted on May 6, 1960

The energy and protein metabolism of pigs growing at a high ambient temperature

1973 ◽  
Vol 16 (2) ◽  
pp. 117-133 ◽  
Author(s):  
C. W. Holmes
Keyword(s):  
High Temperature ◽  
Ambient Temperature ◽  
Nitrogen Retention ◽  
Live Weight ◽  
High Ambient Temperature ◽  
Fat Percentage ◽  
Protein Retention ◽  
Temperature Heat ◽  
Low Levels ◽  
Urinary Nitrogen

SUMMARY1. The experiment was designed to investigate the effect of growth at a high ambient temperature, 33–35°C, on the protein and energy metabolism of pigs, compared with 25°C. The high temperature caused an increase in rectal temperature of 1·4° to 1·7°C. The animals were given two low levels of feeding while growing between 25 and 70 kg live weight; energy and nitrogen retention were measured periodically.2. The apparent digestibilities of the dietary dry matter and energy were decreased and urinary nitrogen losses were increased at the high temperature. Heat production was increased at the high temperature, by between 2% and 10%, the effect becoming more pronounced during the course of the experiment. Retention of energy and nitrogen was reduced at the high temperature.3. The net efficiency of utilization of metabolized energy above maintenance was between 63% and 67%, and was not significantly affected by live weight or temperature. The results suggested that maintenance requirement was increased at the high temperature.4. Analyses of sample joints indicated that the high temperature caused an increase in fat percentage only at the higher level of feeding; this result agreed with fat and protein retention calculated from the balances.

scholarly journals Variations in Plasma Thyroxine Concentrations Throughout One Year in Penned Sheep on a Uniform Feed Intake

1979 ◽  
Vol 32 (3) ◽  
pp. 371 ◽  
Author(s):  
ALC Wallace
Keyword(s):  
Ambient Temperature ◽  
Feed Intake ◽  
Day Length ◽  
Natural Light ◽  
Constant Amount ◽  
Wool Growth ◽  
Total Thyroxine ◽  
The Mean ◽  
One Year

Plasma total thyroxine (T 4) concentrations were measured by radioimmunoassay throughout one year in 10 sheep maintained indoors under natural light and consuming a constant amount of feed. Plasma T4 concentrations varied throughout the year, the highest and lowest values occurring in the spring and autumn months respectively. The mean of all observations was 5 �4�0�1 ,ug/dl. The changes observed did not appear to correlate with changes in ambient temperature, day length or with reported changes in wool growth.

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