Cold exposure of Southdown and Welsh Mountain sheep. 4. Changes in concentrations of free fatty acids, glucose, acetone, protein-bound iodine, protein and antibody in the blood

SUMMARYTwenty-four Southdown and 24 Welsh Mountain year-old female sheep, half on high-plane and half on low-plane nutrition, were shorn and given two acute cold exposures in climate chambers. For 2 weeks before and 2 weeks between exposures the sheep were kept in a subcritical (+ 8°C) or a thermoneutral (+30°C) environment. Before the temperature treatment each sheep received an injection of Brucella abortus vaccine. Blood samples were taken during exposure to + 8°C and + 30°C and during the acute cold exposures for estimation of free fatty acid (FFA), protein-bound iodine (PBI), glucose, acetone, serum protein and antibody levels. FFA and glucose levels alone were measured in 32 similarly treated Scottish Blackface sheep.1. Low plane sheep had higher PBI levels at all temperatures, and higher glucose levels during acute cold exposure than high plane sheep. Otherwise most major effects were attributable to ambient temperature.2. At +8°C the PBI, FFA, glucose, serum protein and acetone levels were higher than at + 30°C.3. Blackface sheep had lower FFA and glucose levels than Southdown and Welsh sheep at both temperatures.4. During acute cold exposure, PBI, acetone and FFA levels increased further. PBI levels were highest in sheep previously at + 30°C, and acetone highest in sheep previously at + 8°C. Very high FFA levels were recorded, especially in sheep not previously cold-acclimatized.5. Glucose levels increased initially, but fell towards the end of acute exposure, suggesting that relatively less carbohydrate and more fat was utilized for energy metabolism during this period.6. Serum protein levels fell during acute exposure, possibly because protein catabolism increased. The proportions of albumin and γ-globulin increased and decreased respectively.7. No effects of temperature on antibody levels were detected.

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Cold exposure of Southdown and Welsh Mountain sheep. 1. Effects of breed, plane of nutrition and acclimatization to cold upon resistance to body cooling

Animal Science ◽

10.1017/s0003356100026635 ◽

1969 ◽

Vol 11 (1) ◽

pp. 65-75 ◽

Cited By ~ 17

Author(s):

A. R. Sykes ◽

J. Slee

Keyword(s):

Cold Exposure ◽

Cold Resistance ◽

Temperature Treatment ◽

Cold Temperature ◽

Acute Exposure ◽

Acute Cold Exposure ◽

Similar Temperature ◽

Body Cooling ◽

Female Sheep

SUMMARY1. Twenty-four Southdown and 24 Welsh Mountain year-old female sheep, half on high plane and half on low plane nutrition, were closely shorn and given two short acute cold exposures (−20°C, 4 mph wind) in climate chambers. For two weeks before the first acute exposure half the sheep were kept at a moderately cold temperature (+8°C) and the remainder at a thermoneutral temperature (+30°C). During the next two weeks between acute exposures these temperatures were reversed for each group of sheep.2. Resistance to body cooling during acute cold exposure was significantly greater after exposure to + 8°C. This was attributed to acclimatization. No further acclimatization resulted from acute cold exposure in addition to chronic moderate cold exposure.3. Sheep which had been kept at +8°C cooled 33% more slowly than those which had been at + 30°C. High plane sheep cooled 34 % more slowly than low plane sheep. Southdowns cooled 32 % more slowly than Welsh sheep, but the Welsh sheep showed relatively greater acclimatization on low plane nutrition.4. Compared with Scottish Blackface sheep given similar temperature treatment in an earlier experiment, the Southdowns and Welsh showed less initial cold resistance and less capacity for acclimatization.

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Acclimatization of Scottish Blackface sheep to cold. 2. Skin temperature, heart rate, respiration rate, shivering intensity and skinfold thickness

Animal Production ◽

10.1017/s0003356100025903 ◽

1968 ◽

Vol 10 (1) ◽

pp. 17-35 ◽

Cited By ~ 20

Author(s):

A. R. Sykes ◽

J. Slee

Keyword(s):

Heart Rate ◽

Skin Temperature ◽

Cold Exposure ◽

Chronic Exposure ◽

Physiological Responses ◽

Skinfold Thickness ◽

Acute Exposure ◽

Heart Rates ◽

Ambient Temperatures ◽

Acute Cold Exposure

Closely shorn Scottish Blackface female sheep aged 9–14 months, half on high plane and half on low plane nutrition, were subjected, in climate chambers, to two short acute cold exposures down to −20°C. The acute exposures were separated by two weeks chronic exposure to a moderately subcriticai temperature (+8°C) or to a thermoneutral temperature (+30°C). Most of the sheep showed a greater resistance to body cooling at the second acute exposure (Slee and Sykes, 1967). This increased resistance to hypothermia, defined as acclimatization, was apparently influenced more by acute than by chronic cold exposure. The present paper deals with changes in skin temperature, heart rate, shivering intensity and skinfold thickness which also resulted from cold exposure, and accompanied acclimatization.After acute cold exposure followed by chronic exposure to +8°C the following changes in these parameters were observed:1. Extremity skin temperatures and heart rates were consistently increased at thermoneutral ambient temperatures.2. Vasoconstriction of the extremities and increased heart rate, both of which normally occur during the early stages of cold exposure, were delayed.3. Heart rates at sub-zero ambient temperatures were increased.4. Cold-induced vasodilatation at sub-zero ambient temperatures was increased.After acute cold treatment alone the intensity of shivering during the second acute exposure was reduced. Also the onset of foot vasoconstriction was slightly delayed.A highly significant relationship was observed between shivering intensity and heart rate during cold exposure.Plane of nutrition had less effect on the physiological responses to cooling than did previous cold experience.It was suggested in discussion that the physiological responses associated with acclimatization were: elevated basal metabolic rate, delayed onset of vasoconstriction and delayed metabolic response to cold, and consequent lowering of the critical temperature. Summit metabolism was also increased and shivering intensity reduced during acute cold exposure. Some of these responses could have resulted from either acute or chronic moderate cold exposure. However their persistence, once induced, appeared to depend upon continued exposure to moderate cold.

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Cold Exposure of Southdown and Welsh Mountain Sheep. 3. Changes in plasma calcium, phosphorus, magnesium, sodium and potassium levels

Animal Science ◽

10.1017/s0003356100026659 ◽

1969 ◽

Vol 11 (1) ◽

pp. 91-99 ◽

Cited By ~ 9

Author(s):

A. R. Sykes ◽

A. C. Field ◽

J. Slee

Keyword(s):

Plasma Concentration ◽

Cold Exposure ◽

Plasma Calcium ◽

Blood Samples ◽

Acute Cold Exposure ◽

Calcium Phosphorus ◽

Environmental Temperatures ◽

Female Sheep ◽

Sodium And Potassium ◽

Temperature Interactions

SUMMARYSouthdown and Welsh Mountain female sheep, equal numbers on high and low plane nutrition, were shorn and subjected to two acute cold exposures (−20°C, 4 mph wind) in climate chambers. Before the first exposure the sheep were kept in either a cool (+8°C) or a thermoneutral (+30°C) environment for two weeks. Between exposures these environmental temperatures were reversed within groups. Blood samples were withdrawn at the beginning and end of the two week exposures and on three occasions during acute cold exposure. Plasma analyses of Ca, P, Mg, Na and K were carried out. Exposure to +8°C caused a 12% reduction in plasma Mg levels of all sheep, but had no effect on Ca, Na or K levels. There were breed × temperature interactions with respect to plasma P levels. Acute cold exposure caused reductions in plasma Mg and Ca levels and an increase in plasma P levels of all groups of sheep. Changes in plasma Na and K levels could have been caused by plasma concentration.Electrolyte levels initially displaced by exposure to +8°C showed no evidence of a return to normality two weeks later. Only for Ca was there evidence that prior exposure to +8°C modified the response to acute cold exposure.

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Glucose metabolism in thyroidectomized and normal dogs during rest and acute cold exposure

Journal of Applied Physiology ◽

10.1152/jappl.1975.38.2.236 ◽

1975 ◽

Vol 38 (2) ◽

pp. 236-240 ◽

Cited By ~ 5

Author(s):

P. Paul ◽

M. Donohue ◽

W. L. Holmes

Keyword(s):

Energy Expenditure ◽

Glucose Level ◽

Cold Exposure ◽

Plasma Glucose ◽

Turnover Rate ◽

Control Period ◽

Glucose Turnover ◽

Glucose Levels ◽

Acute Cold Exposure ◽

Lower Glucose

Uniformly labeled (14C)glucose was infused iv at a constant rate into unanesthetized surgically thyroidectomized (THY) and normal dogs during the basal state at 22 degrees C and during cold exposure at 4–5 degrees C. 02 uptake, CO2 output, and plasma glucose levels were determined; from these rates of glucose turnover and oxidation were calculated. Comparison of THY with normal dogs shows that at a mean plasma glucose level of 103 mg/100 ml, a significantly lower glucose turnover rate was observed in THY dogs on the basis of a kg body weight, body surface area (m-2), but not per cal BMR. The same percentage of glucose turnover was immediately oxidized in THY and normal dogs, accounting for 16 and 15% of the total caloric expenditure, respectively. Acute cold exposure increased energy expenditure in both THY and normal dogs without a change in glucose level or turnover rate. However, the percentage of glucose turnover which was immediately oxidized as well as the amount of glucose oxidized increased significantly and proportionally to the increase in energy expenditure so that the percent of calories derived from plasma glucose oxidation remained the same as that observed during the control period.

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577-P: Increased Symptoms of Peripheral Neuropathy and Depression in Insulin-Treated Type 2 Diabetic Patients Are Associated with Reduced BDNF Serum Protein Levels and Val66Met-SNP

Diabetes ◽

10.2337/db19-577-p ◽

2019 ◽

Vol 68 (Supplement 1) ◽

pp. 577-P

Author(s):

AMIR BASHKIN ◽

AKRAM SAFADI ◽

BELLA GROSS ◽

NETANEL A. HOROWITZ ◽

RIVKA SHARON ◽

...

Keyword(s):

Peripheral Neuropathy ◽

Serum Protein ◽

Diabetic Patients ◽

Type 2 Diabetic Patients ◽

Protein Levels ◽

Type 2 Diabetic

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Cold-induction of afadin in brown fat supports its thermogenic capacity

Scientific Reports ◽

10.1038/s41598-021-89207-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Morten Lundh ◽

Ali Altıntaş ◽

Marco Tozzi ◽

Odile Fabre ◽

Tao Ma ◽

...

Keyword(s):

Cold Exposure ◽

Functional Enrichment ◽

Activation Process ◽

Target Tissue ◽

Cold Stimulation ◽

Brown Adipocytes ◽

Protein Levels ◽

Mrna Induction ◽

Metabolic Functions ◽

Brown Adipose

AbstractThe profound energy-expending nature of brown adipose tissue (BAT) thermogenesis makes it an attractive target tissue to combat obesity-associated metabolic disorders. While cold exposure is the strongest inducer of BAT activity, the temporal mechanisms tuning BAT adaptation during this activation process are incompletely understood. Here we show that the scaffold protein Afadin is dynamically regulated by cold in BAT, and participates in cold acclimation. Cold exposure acutely increases Afadin protein levels and its phosphorylation in BAT. Knockdown of Afadin in brown pre-adipocytes does not alter adipogenesis but restricts β3-adrenegic induction of thermogenic genes expression and HSL phosphorylation in mature brown adipocytes. Consistent with a defect in thermogenesis, an impaired cold tolerance was observed in fat-specific Afadin knockout mice. However, while Afadin depletion led to reduced Ucp1 mRNA induction by cold, stimulation of Ucp1 protein was conserved. Transcriptomic analysis revealed that fat-specific ablation of Afadin led to decreased functional enrichment of gene sets controlling essential metabolic functions at thermoneutrality in BAT, whereas it led to an altered reprogramming in response to cold, with enhanced enrichment of different pathways related to metabolism and remodeling. Collectively, we demonstrate a role for Afadin in supporting the adrenergic response in brown adipocytes and BAT function.

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Effect of milk replacer allowance on calf faecal bacterial community profiles and fermentation

Animal Microbiome ◽

10.1186/s42523-021-00088-2 ◽

2021 ◽

Vol 3 (1) ◽

Author(s):

Sandeep Kumar ◽

M. Ajmal Khan ◽

Emma Beijer ◽

Jinxin Liu ◽

Katherine K. Lowe ◽

...

Keyword(s):

Fatty Acids ◽

Body Weight ◽

Bacterial Community ◽

Bacterial Diversity ◽

Serum Protein ◽

Bacterial Communities ◽

Short Chain Fatty Acids ◽

Short Chain ◽

Milk Replacer ◽

Protein Levels

Abstract Background The nutrition of calves from birth until weaning is predominantly from liquid (milk or milk-based) feeds. Liquid feed allowances are often restricted during artificial rearing to accelerate the development of the rumen by promoting solid feed intake. Liquid feeds bypass the rumen and are digested in the lower digestive tract, however, the influence of different types of milk feeds, and their allowances, on the calf hindgut microbiota is not well understood. In this study, faecal samples from 199 calves raised on three different allowances of milk replacer: 10% of initial bodyweight (LA), 20% of initial bodyweight (HA), and ad libitum (ADLIB), were collected just prior to weaning. Bacterial community structures and fermentation products were analysed, and their relationships with calf growth and health parameters were examined to identify potential interactions between diet, gut microbiota and calf performance. Results Differences in the total concentrations of short-chain fatty acids were not observed, but higher milk replacer allowances increased the concentrations of branched short-chain fatty acids and decreased acetate to propionate ratios. The bacterial communities were dominated by Ruminococcaceae, Lachnospiraceae and Bacteroides, and the bacterial diversity of the ADLIB diet group was greater than that of the other diet groups. Faecalibacterium was over three times more abundant in the ADLIB compared to the LA group, and its abundance correlated strongly with girth and body weight gains. Milk replacer intake correlated strongly with Peptococcus and Blautia, which also correlated with body weight gain. Bifidobacterium averaged less than 1% abundance, however its levels, and those of Clostridium sensu stricto 1, correlated strongly with initial serum protein levels, which are an indicator of colostrum intake and passive transfer of immunoglobulins in early life. Conclusions Higher milk replacer intakes in calves increased hindgut bacterial diversity and resulted in bacterial communities and short chain fatty acid profiles associated with greater protein fermentation. Increased abundances of beneficial bacteria such as Faecalibacterium, were also observed, which may contribute to development and growth. Moreover, correlations between microbial taxa and initial serum protein levels suggest that colostrum intake in the first days of life may influence microbiota composition at pre-weaning.

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