scholarly journals The influence of environmental temperatures on farrowing rates and litter sizes in South African pig breeding units

2014 ◽  
Vol 81 (1) ◽  
Author(s):  
Leana Janse van Rensburg ◽  
Brian T. Spencer
Keyword(s):  
South African ◽  
Temperature Control ◽  
Environmental Temperature ◽  
Control Mechanisms ◽  
Ambient Temperatures ◽  
Commercial Breeding ◽  
Weather Stations ◽  
Main Determinants ◽  
Environmental Temperatures ◽  
Farrowing Rate

The reproductive performance of pigs is one of the main determinants of the profit farmers make from pig production. This study was undertaken to describe whether periods of high environmental temperature have an effect on the farrowing rate, litter sizes and number of stillbirths in commercial breeding units in South Africa. Data were collected weekly from four commercial breeding units with good records from December 2010 to August 2012. These data included the number of sows mated, number of sows farrowed and number of piglets born alive, as well as the number of stillbirths. Note was also taken of whether environmental temperature control mechanisms were employed. Temperature data from weather stations within 100 km of the breeding units were obtained from the South African Weather Service. In all breeding units a decrease in farrowing rate following mating during severe average temperatures (> 30 °C) when compared to the farrowing rate following mating during mild average temperatures (< 22 °C) was observed. When mating occurred at higher temperatures, the resultant litter size was marginally decreased in the breeding units that did not employ environmental temperature control, but was unaffected in the breeding units that did. In all four breeding units the trend was for the average number of piglets born alive to increase as the environmental temperature around the time of farrowing increased and the trend in three of the four breeding units was for the percentage of stillbirths per litter to decrease with increased temperature around the time of farrowing. The most significant observation in this study was the trend for farrowing rates to decrease following inseminations during times of high ambient temperatures (> 30 °C). Environmental temperature control did not negate this effect, but the breeding units employing the environmental temperature control did show higher average farrowing rates overall.

Shorn and unshorn Awassi sheep II. Pulse rate

1963 ◽  
Vol 60 (2) ◽  
pp. 169-173 ◽  
Author(s):  
E. Eyal
Keyword(s):  
Body Temperature ◽  
Pulse Rate ◽  
Environmental Temperature ◽  
Direct Sunlight ◽  
Ambient Temperatures ◽  
Awassi Sheep ◽  
Summer Temperatures ◽  
Vasomotor Activity ◽  
Environmental Temperatures ◽  
Daily Changes

1. A comparison was made between the pulse rate of shorn and unshorn sheep maintained in the shade and direct sunlight during the various seasons of the year.2. The variability of the pulse rate during the day generally agreed with the daily changes in body temperature and presumed level of metabolism. Fluctuations were greater in unshorn sheep.3. Pulse rate was lower during summer (60–100 for unshorn and 63–100 for shorn sheep) than in winter (90–130 for unshorn and 90–115 for shorn sheep). It tended to increase with a rise in ambient temperature, especially during winter and spring. A lower pulse rate accompanied a rise in environmental temperature, during summer. The slowest pulse rate of 42 per minute was observed during summer in the hot dry area.4. The pulse rate of both groups increased with a rise in rectal temperature, particularly at low ambient temperatures. At comparable rectal temperatures, a higher average pulse rate was observed in shorn sheep during winter and spring. With elevated summer temperatures, equal pulse rates were noted in both groups of equal rectal temperatures. Since the rectal temperatures of the shorn exceeded that of unshorn sheep, in high environmental temperatures, and in the sun, their pulse rate under these conditions was also higher.5. The differences in pulse rate between the two groups appeared to reflect the combined effects of metabolic rate, body temperature and the vasomotor activity, all of which vary with season and environmental temperatures.

Shorn and unshorn Awassi sheep I. Body temperature

1963 ◽  
Vol 60 (2) ◽  
pp. 159-168 ◽  
Author(s):  
E. Eyal
Keyword(s):  
Body Temperature ◽  
Relative Humidity ◽  
Heat Tolerance ◽  
Environmental Temperature ◽  
The Body ◽  
The Sun ◽  
Direct Sunlight ◽  
Ambient Temperatures ◽  
Awassi Sheep ◽  
Environmental Temperatures

1. The rectal temperatures of shorn and unshorn Awassi sheep were measured at various hours of the day and during various seasons of the year in two different locations in Israel.2. An increase in body temperature accompanied an increase in environmental temperature. A steeper temperature increase was noted in shorn sheep kept in the shade. When ambient temperatures were below 30° C. the body temperature of shorn sheep was lower than that of the unshorn sheep by an average of 0·16° C.3. When ambient temperatures were above 30° C. the body temperature of shorn sheep was equal to or higher than that of unshorn ones.4. Upon exposure to direct sunlight, the body temperature of shorn sheep exceeded that of unshorn animals. However, when the animals were transferred to the shade, or after sunset, the shorn sheep cooled at a faster rate. Their body temperature fell below that of the unshorn sheep during the cool hours of the day.5. Wind velocity, both in the shade and in the sun, had a greater effect on shorn than on unshorn sheep.6. A rise in the relative humidity of ambient temperatures above 25° C. caused body temperature to rise, particularly in unshorn animals. The body temperature of shorn sheep exceeded that of unshorn ones when the animals were maintained in a hot and dry environment.7. While the body of the shorn sheep was entirely affected by the macroclimate, the unshorn sheep were greatly influenced by the microclimate existing in the fleece. Fleece temperatures always lagged behind and were rarely equal to environmental temperatures. Since it was postulated that heat tolerance of certain animals was related to their ability to exploit cool hours of the day, it is suggested that in certain ‘tolerance tests’ records should be taken not only during exposure to heat but also during cool hours of the day.

Dealing with hot rocky environments: Critical thermal maxima and locomotor performance in Leptodactylus lithonaetes (Anura: Leptodactylidae)

2019 ◽  
pp. 155-161 ◽  
Author(s):  
Ivan Beltran
Keyword(s):  
Environmental Temperature ◽  
Extreme Temperature ◽  
Effect Of Temperature ◽  
Maximum Speed ◽  
Locomotor Performance ◽  
Extreme Temperatures ◽  
Physiological Limits ◽  
Fitness Consequences ◽  
Thermal Maximum ◽  
Environmental Temperatures

Environmental temperature has fitness consequences on ectotherm development, ecology and behaviour. Amphibians are especially vulnerable because thermoregulation often trades with appropriate water balance. Although substantial research has evaluated the effect of temperature in amphibian locomotion and physiological limits, there is little information about amphibians living under extreme temperature conditions. Leptodactylus lithonaetes is a frog allegedly specialised to forage and breed on dark granitic outcrops and associated puddles, which reach environmental temperatures well above 40 ˚C. Adults can select thermally favourable microhabitats during the day while tadpoles are constrained to rock puddles and associated temperature fluctuations; we thus established microhabitat temperatures and tested whether the critical thermal maximum (CTmax) of L. lithonaetes is higher in tadpoles compared to adults. In addition, we evaluated the effect of water temperature on locomotor performance of tadpoles. Contrary to our expectations, puddle temperatures were comparable and even lower than those temperatures measured in the microhabitats used by adults in the daytime. Nonetheless, the CTmax was 42.3 ˚C for tadpoles and 39.7 ˚C for adults. Regarding locomotor performance, maximum speed and maximum distance travelled by tadpoles peaked around 34 ˚C, approximately 1 ˚C below the maximum puddle temperatures registered in the puddles. In conclusion, L. lithonaetes tadpoles have a higher CTmax compared to adults, suggesting a longer exposure to extreme temperatures that lead to maintain their physiological performance at high temperatures. We suggest that these conditions are adaptations to face the strong selection forces driven by this granitic habitat.

Effects of Buserelin on day of service or 12 days post service on farrowing rate and litter size to first service in outdoor sows and gilts

1999 ◽  
Vol 1999 ◽  
pp. 176-176
Author(s):  
A.R. Peters ◽  
L.A. Dwyer ◽  
A. Dawson ◽  
P.A. Canham ◽  
J.D. Mackinnon
Keyword(s):  
Treatment Group ◽  
Litter Size ◽  
East Anglia ◽  
Treatment Groups ◽  
Prolonged Weaning ◽  
Breeding Herd ◽  
Commercial Breeding ◽  
Buserelin Treatment ◽  
Seasonal Infertility ◽  
Farrowing Rate

The problem of seasonal infertility in pigs has been recognised for many years. The infertility complex can may be manifested by increased returns to service, prolonged weaning to oestrus intervals and decreased litter size. The purpose of this trial was to evaluate the effects of Buserelin treatment on fertility in sows and gilts during the seasonally infertile period.A total of 1231 mixed parity sows and gilts from five outdoor herds in East Anglia were randomly assigned to one of three treatment groups. Any sows not presented for service at first post weaning oestrus were excluded. All sows and gilts judged to be in adequate health and condition to be kept in a commercial breeding herd were included. Group C sows and gilts were given no treatment. Group R1 sows and gilts were injected i.m. with 8μg Buserelin (2.0ml Receptal; Hoechst Roussel Vet UK Ltd) on the day of service.

The effects of environmental temperature and method of feeding on the performance and carcass composition of bacon pigs

1967 ◽  
Vol 9 (2) ◽  
pp. 209-218 ◽  
Author(s):  
D. W. Holme ◽  
W. E. Coey
Keyword(s):  
Environmental Temperature ◽  
Average Daily Gain ◽  
Carcass Composition ◽  
Restricted Feeding ◽  
Feed Conversion ◽  
Feeding Method ◽  
Feeding Regimes ◽  
Higher Temperature ◽  
Ad Libitum ◽  
Environmental Temperatures

A trial designed to investigate the effects of two environmental temperatures, three feeding regimes and the interactions between them is described. A temperature of 72° F. was better than one of 54° F. for bacon pigs between 40 lb. and 200 lb. weight. The higher temperature resulted in faster growth, more efficient feed conversion and increased length of carcass. Other carcass characteristics were not significantly altered. Ad libitum feeding resulted in faster growth and fatter carcasses than restricted feeding, but did not have a significant effect on efficiency of feed conversion. When feed intake was restricted, feeding pigs once daily or twice daily resulted in similar performance and carcass composition.There was a significant interaction between environmental temperature and feeding method for average daily gain in that pigs fed ad libitum grew faster at the low temperature and pigs fed restricted amounts of feed grew faster at the high temperature. No other interaction reached significant levels.

Effect of ambient temperature on protein breakdown during prolonged exercise

1988 ◽  
Vol 64 (2) ◽  
pp. 550-555 ◽  
Author(s):  
D. G. Dolny ◽  
P. W. Lemon
Keyword(s):  
Ambient Temperature ◽  
Prolonged Exercise ◽  
Respiratory Exchange Ratio ◽  
Protein Breakdown ◽  
Protein Utilization ◽  
Post Exercise ◽  
Ambient Temperatures ◽  
Environmental Temperatures ◽  
Male Subjects ◽  
H Protein

Male subjects (n = 8) cycled for 90 min in 5, 20, and 30 degrees C environments. Rectal (Tre), chest, and thigh temperatures, O2 consumption (VO2), respiratory exchange ratio (R), and venous concentrations of glucose, free fatty acids (FFA), urea N, lactic acid (LA), norepinephrine (NE), epinephrine (E), and cortisol (C) were measured before, during, and after exercise. Urea N excretion was measured in 72 h of nonexercise, in 72 h of exercise (exercise day + 2 post-exercise days) urine samples, and in exercise sweat. Calculated 72-h protein utilization (means +/- SE) was significantly greater (P less than 0.05) for the 5 (86.9 +/- 27.1 g) and 20 (82.9 +/- 22.7 g) compared with 30 degrees C (34.01 +/- 19.1 g) trial. Regardless of ambient temperature exercise increased the venous concentration of C, E, and NE. These catabolic hormones were greatest in 5, lowest in 20, and intermediate in 30 degrees C. Exercise Tre and VO2 were greatest in the 30 degrees C environment. Venous FFA concentration was significantly higher and R significantly lower in 5 vs. 20 or 30 degrees C, and venous LA concentration was significantly greater in 30 vs. 20 or 5 degrees C. Although these results indicate that exercise protein breakdown is affected by ambient temperatures, the mechanism of action is not due solely to circulating NE, E, and C. Differences in venous FFA and LA across environmental temperatures suggest that alterations in carbohydrate and fat metabolism may have contributed to the observed variable protein utilization.

scholarly journals Effects of 7°C environmental temperature acclimation during a 3-week training period

2020 ◽  
Vol 128 (4) ◽  
pp. 768-777
Author(s):  
Robert Shute ◽  
Katherine Marshall ◽  
Megan Opichka ◽  
Halee Schnitzler ◽  
Brent Ruby ◽  
...  
Keyword(s):  
Room Temperature ◽  
Environmental Temperature ◽  
Cellular Signaling ◽  
Temperature Acclimation ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor ◽  
Training Adaptations ◽  
Before And After ◽  
The Impact ◽  
Environmental Temperatures

Cold environmental temperatures during exercise and recovery alter the acute response to cellular signaling and training adaptations. Approximately 3 wk is required for cold temperature acclimation to occur. To determine the impact of cold environmental temperature on training adaptations, fitness measurements, and aerobic performance, two groups of 12 untrained male subjects completed 1 h of cycling in 16 temperature acclimation sessions in either a 7°C or 20°C environmental temperature. Fitness assessments before and after acclimation occurred at standard room temperature. Muscle biopsies were taken from the vastus lateralis muscle before and after training to assess molecular markers related to mitochondrial development. Peroxisome proliferator-activated receptor-γ coactivator 1α ( PGC-1α) mRNA was higher in 7°C than in 20°C in response to acute exercise before training ( P = 0.012) but not after training ( P = 0.813). PGC-1α mRNA was lower after training ( P < 0.001). BNIP3 was lower after training in the 7°C than in the 20°C group ( P = 0.017) but not before training ( P = 0.549). No other differences occurred between temperature groups in VEGF, ERRα, NRF1, NRF2, TFAM, PINK1, Parkin, or BNIP3L mRNAs ( P > 0.05). PGC-1α protein and mtDNA were not different before training, after training, or between temperatures ( P > 0.05). Cycling power increased during the daily training ( P < 0.001) but was not different between temperatures ( P = 0.169). V̇o2peak increased with training ( P < 0.001) but was not different between temperature groups ( P = 0.460). These data indicate that a 3-wk period of acclimation/training in cold environmental temperatures alters PGC-1α gene expression acutely but this difference is not manifested in a greater increase in V̇o2peak and is dissipated as acclimation takes place. NEW & NOTEWORTHY This study examines the adaptive response of cellular signaling during exercise in cold environmental temperatures. We demonstrate that peroxisome proliferator-activated receptor-γ coactivator 1α mRNA is different between cold and room temperature environments before training but after training this difference no longer exists. This initial difference in transcriptional response between temperatures does not lead to differences in performance measures or increases in protein or mitochondria.

LOW-TEMPERATURE ENVIRONMENTAL STRESS AND THE METABOLISM OF VITAMIN A IN THE RAT

1962 ◽  
Vol 40 (1) ◽  
pp. 491-499 ◽  
Author(s):  
W. E. J. Phillips
Keyword(s):  
Low Temperature ◽  
Vitamin A ◽  
Environmental Stress ◽  
Room Temperature ◽  
Environmental Temperature ◽  
Sprague Dawley ◽  
Vitamin A Metabolism ◽  
Environmental Temperatures

Carotene and vitamin A metabolism in the rat were studied at two environmental temperatures. The utilization of carotene is greater in animals maintained at a low environmental temperature (2°) than at room temperature (22°). This occurred within a period of 3 days. Both the hepatic storage and the rate of metabolism of orally administered vitamin A were unaffected by environmental temperature. The response of Wistar and Sprague–Dawley strains was similar.

scholarly journals Thermodynamic Analysis of Transcritical CO2 Ejector Expansion Refrigeration Cycle with Dedicated Mechanical Subcooling

Entropy ◽  
2019 ◽  
Vol 21 (9) ◽  
pp. 874
Author(s):  
Fu ◽  
Wang ◽  
Zheng ◽  
Yu ◽  
Liu ◽  
...  
Keyword(s):  
Thermodynamic Analysis ◽  
Environmental Temperature ◽  
Exergy Efficiency ◽  
Coefficient Of Performance ◽  
Refrigeration Cycle ◽  
Evaporation Temperature ◽  
Mass Ratios ◽  
Environmental Temperatures

: The new configuration of a transcritical CO2 ejector expansion refrigeration cycle combined with a dedicated mechanical subcooling cycle (EMS) is proposed. Three mass ratios of R32/R1234ze(Z) (0.4/0.6, 0.6/0.4, and 0.8/0.2) were selected as the refrigerants of the mechanical subcooling cycle (MS) to further explore the possibility of improving the EMS cycle’s performance. The thermodynamic performances of the new cycle were evaluated using energetic and exergetic methods and compared with those of the transcritical CO2 ejector expansion cycle integrated with a thermoelectric subcooling system (ETS). The results showed that the proposed cycle presents significant advantages over the ETS cycle in terms of the ejector performance and the system energetic and exergetic performances. Taking the EMS cycle using R32/R1234ze(Z) (0.6/0.4) as the MS refrigerant as an example, the improvements in the coefficient of performance and system exergy efficiency were able to reach up to 10.27% and 15.56%, respectively, at an environmental temperature of 35 C and evaporation temperature of −5 C. Additionally, the advantages of the EMS cycle were more pronounced at higher environmental temperatures.

scholarly journals Symmetric Deflection of CFRP-Based Polymeric Laminate

2011 ◽  
Vol 2-3 ◽  
pp. 966-971
Author(s):  
Wen Yi Lin ◽  
Minoru Sasaki ◽  
Hirohisa Tamagawa
Keyword(s):  
Temperature Control ◽  
Environmental Temperature ◽  
Control Method ◽  
Successful Outcome ◽  
Metal Composite ◽  
Ionic Polymer Metal Composite ◽  
Laminate Structure ◽  
Ionic Polymer ◽  
Polymer Metal ◽  
Soft Actuators

Unlike well-investigated polymer-based soft actuators such as gel, Ionic Polymer-Metal Composite, conducting polymer, a CFRP-based polymeric laminate possesses quite distinguished properties. It was previously reported that a CFRP-PVC laminate exhibited two-way deflection in accordance with environmental temperature, but it was asymmetric deflection due to the asymmetric laminate structure. In this study, we successfully fabricated a new CFRP-based polymeric laminate which can exhibit symmetric deflection. Despite such a successful outcome, there was large room to improve the degree of its deflection. Improvement of temperature control method for the newly fabricated CFRP-based polymeric laminate resulted in enhancement of the degree of its deflection.

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