Effect of chronic food restriction on pulsatile luteinizing hormone secretion and hypothalamic neuropeptide Y gene expression in castrate male sheep

1997 ◽  
Vol 152 (2) ◽  
pp. 329-337 ◽  
Author(s):  
C L Adam ◽  
P A Findlay ◽  
C E Kyle ◽  
P Young ◽  
J G Mercer
Keyword(s):  
Gene Expression ◽  
Neuropeptide Y ◽  
Pulse Amplitude ◽  
Pulse Frequency ◽  
High Energy ◽  
Low Energy ◽  
High Protein ◽  
Castrate Male ◽  
Low Protein ◽  
Male Sheep

Abstract Castrate male sheep (wethers, average liveweight 38 ± 0·6 kg) were given one of the following diets for 10 weeks followed by euthanasia (n=8/group): high-energy high-protein providing 1·5 times the energy required to maintain liveweight (maintenance) (group 1·5M), low-energy low-protein at 0·5 maintenance (0·5M), or low-energy high-protein at 0·5 maintenance (0·5M+P). 1·5M wethers gained 22% liveweight whereas 0·5M and 0·5M+P wethers lost 18 and 13% liveweight respectively. Relative to the 1·5M group, the 0·5M and 0·5M+P groups had similar plasma concentrations of glucose and cortisol throughout, but elevated non-esterified fatty acids (P<0·001) and reduced IGF-I and insulin (P<0·05, 0·01 or 0·001) from 1 week onwards. Each week blood samples were taken every 12 min for 4 h and plasma assayed for LH. Mean concentration over 4 h, LH pulse frequency and LH pulse amplitude showed no progressive change in 1·5M sheep. However, in both 0·5M and 0·5M+P groups mean LH increased (P<0·001 and P<0·01 respectively), pulse frequency decreased (P<0·01 and P<0·01) and pulse amplitude increased (P<0·001 and P<0·01) over the 10-week period. Anterior pituitary LH content was greater in 0·5M (P<0·01) and 0·5M+P (P<0·05) than in 1·5M sheep. Coronal sections (20 μm) of hypothalamic brain tissue were subjected to in situ hybridisation to determine gene expression for neuropeptide Y (NPY). NPY mRNA was concentrated in the arcuate nucleus and median eminence, with total amounts greater in both 0·5M (310%, P<0·001) and 0·5M+P (333%, P<0·01) groups than in 1·5M sheep (100%). These data reveal that chronic low dietary energy intake by long-term castrates, with high or low protein intake, reduces LH pulse frequency but increases the circulating levels of LH by virtue of an increase in pulse amplitude, and concomitantly increases hypothalamic NPY gene expression. Journal of Endocrinology (1997) 152, 329–337

scholarly journals EFFECTS OF SEVERE ENERGY VERSUS PROTEIN DEPRIVATION DURING GESTATION OF REPRODUCTIVE PERFORMANCE AND BLOOD METABOLITES OF GILTS

2021 ◽  
Vol 11 (2) ◽  
pp. 132-139
Author(s):  
F. O. I. Anugwa ◽  
W. G. Pond
Keyword(s):  
Reproductive Performance ◽  
Plasma Glucose ◽  
High Energy ◽  
Low Energy ◽  
High Protein ◽  
Feeding Rates ◽  
Glucose Levels ◽  
Low Protein ◽  
Versus Protein ◽  
Feed Costs

Diets designated as high energy, high protein (HEHP), low energy, high protein (LEHP), high energy, low protein (HELP) and low energy, low protein (LELP) were fed to gilts from breeding through farrowing. Feeding rates were 1.82 (HEHP, HELP) or 0.68 kg (LEHP LELP) of diet per gilt per day. Diets were calculated to provide 6.6 (HEHP, HELP) or 2.2 Meal (LEHP, LELP) of digestible energy and 272 (HEHP, LEHP) or 60 g (HELP, LELP) of protein per gilt per day. Protein contents of the HEHP, LEHP, HELP and LELP diets were 15, 40, 3.3 and 9%. All sows and their progeny were treated similarly after farrowing. Gilts on the high energy diets (HEHP, HELP) gained significantly more weight during gestation than the gilts on the low energy diets (LEHP, LELP). Farrowing percentages were 100, 100, 80 and 40% for the HEHP, HELP, LEHP and LELP gilts respectively. Average litter size, birth weight, number of pigs weaned per litter or weaning weights were not significantly different among treatments. At the same stages of gestation, there were no significant differences among treatments in plasma glucose levels but plasma glucose significantly increased (P<0.05) in all treatments with advancing pregnancy. Serum albumun concentrations were significantly lower (P<0.05) in the HELP group than in the other groups by the end of gestation. The data indicate that lowering protein intake during gestation may be one way of reducing feed costs without impairing reproductive performance.

Estimation of microbial protein flow from the rumen of sheep using microbial nucleic acid and urinary excretion of purine derivatives

1992 ◽  
Vol 72 (4) ◽  
pp. 821-830 ◽  
Author(s):  
R. Puchala ◽  
G. W. Kulasek
Keyword(s):  
Nucleic Acids ◽  
Energy Content ◽  
High Energy ◽  
Low Energy ◽  
High Protein ◽  
Microbial Protein ◽  
Purine Derivatives ◽  
Low Protein ◽  
Microbial Nitrogen ◽  
Sheep Rumen

Two methods for estimating the flow of microbial protein synthesized in the rumen to the duodenum were compared: one uses microbial nucleic acids entering the duodenum, and the other uses allantoin excreted in the urine. Ten ewes were fitted with rumen and duodenum cannulae, as well as Foley catheters for collection of urine. The experiment was carried out using two series of treatments with two replications each. The ewes were randomly divided into five groups, which were assigned to one of five diets. (In the second series sheep were excluded from diets received in the first series.) The diets, differing in protein and energy content, were as follows: (1) low protein, low energy (LPLE); high protein, low energy (HPLE); (3) maintenance for protein and energy (MPME); (4) low protein, high energy (LPHE); and (5) high protein, high energy (HPHE). The rates of rumen microbial protein synthesis were 3.34, 7.00, 9.44, 4.47 and 13.44 g microbial nitrogen (N) d−1 for diets 1–5, respectively. Results indicated a high correlation between allantoin and total purine derivatives (allantoin, uric acid, xanthine and hypoxanthine) excreted in the urine and the amount of microbial nucleic acids entering the duodenum. A regression equation y = exp (0.830 + 2.089x), using allantoin N (g d−1) excreted in the urine, was proposed for estimating microbial N synthesis (g d−1) in the rumen. The ratio of allantoin N to creatinine N in the urine samples collected at 6-h intervals varied markedly. Key words: Sheep, rumen, microbial protein, allantoin, purine derivatives

The effect of nutrition on the reproductive performance of first-litter sows 2. Protein and energy intakes during lactation

1984 ◽  
Vol 38 (2) ◽  
pp. 249-256 ◽  
Author(s):  
R. H. King ◽  
I. H. Williams
Keyword(s):  
Protein Intake ◽  
Live Weight ◽  
High Energy ◽  
Low Energy ◽  
High Protein ◽  
Weight Losses ◽  
Lactation Length ◽  
Low Protein ◽  
Daily Intakes ◽  
Dietary Treatments

A factorial experiment involving high (53·1 to 59·5 MJ) and low (25·4 to 27·1 MJ) daily intakes of digestible energy, and high (550 to 745 g) and low (302 to 318 g) daily intakes of crude protein during lactation, was conducted with 68 first-litter sows. Average lactation length was 32 days, and average backfat changes during lactation were +0·3, −1·4, −7·2 and −5·4 mm for the high energy/high protein, high energy/low protein, low energy/high protein and low energy/low protein combinations, respectively. The corresponding mean live-weight losses during lactation were 3·9, 32·5, 29·8 and 35·8 kg. Within 8 days of weaning, more sows receiving high intakes of both energy and protein during lactation exhibited oestrus (0·88 v. 0·53, x2 = 6·7, P < 0·01) than sows whose energy and/or protein intake throughout lactation had been restricted. Nitrogen balances of sows were determined between 18 and 22 days after farrowing. Sows receiving high intakes of both energy and protein during lactation were in positive nitrogen balance, whereas the nitrogen balances of sows on the other three dietary treatments during lactation were similar to each other but negative. Ovulation rate, subsequent litter size and embryo mortality were not significantly affected by energy or protein intake during lactation.

CARCASS QUALITY OF RAW AND SMOKED FISH FILLETS PREPARED FROM CAGE RAISED RIVER CATFISH (Hemibagrus nemurus Valenciennes, 1840) FED HIGH PROTEIN-LOW ENERGY AND LOW PROTEIN-HIGH ENERGY DIETS

2016 ◽  
Vol 78 (4-2) ◽  
Author(s):  
Bustari Hasan ◽  
Indra Suharman ◽  
Desmelati Desmelati ◽  
Dian Iriani
Keyword(s):  
Protein Composition ◽  
High Energy ◽  
Low Energy ◽  
High Protein ◽  
Carcass Quality ◽  
Commercial Fish ◽  
Overall Acceptability ◽  
Smoked Fish ◽  
Low Protein

The purpose of this study was to evaluate the effect of high protein-low energy and low protein-high energy diet on carcass quality of raw and smoked river catfish fillets. Two diets containing high protein-low energy (40 % protein, 2.75 kcal g–1 energy, diet A) and low protein-high energy (34 % protein, 3.00 kcal·g-1 energy, diet B) which produced the best growth in our previous feeding trial were fed to river catfish. The fish, 40.14 g to 42.64 g in weight were stocked in commercial fish cage at dencity of 50 fish per m3and fed the experimental diets for 90 d. At the end of the experiment, all fish was weighed for weight gain, 20 fish were evaluated for carcass quality and other 20 fish were filleted and hot smoked. Smoked fillets were assessed for smoking yield, proximate composition, sensory quality and overall acceptability. Edible flesh, dressing percentage and flesh water holding capacity  of the fresh raw were higher for the fish fed diet A; but carcass waste was higher for the fish fed diet B. Protein composition was higher for the fish fed diet A; however, fat composition was higher for the fish fed diet B. In terms of smoking yield and overall acceptability of smoked fish, there was no difference between smoked fillets prepared from the fish fed the two diets, while appearance and texture were higher for the smoked fillets prepared from fish fed diet A; and odor as well as flavor were higher for smoked fillets prepared from fish fed diet B. 

Effect of diets with different energy and protein levels on performance of grower ostriches

2008 ◽  
Vol 48 (10) ◽  
pp. 1338 ◽  
Author(s):  
P. C. Glatz ◽  
Z. H. Miao ◽  
B. K. Rodda ◽  
S. C. Wyatt
Keyword(s):  
High Protein Diet ◽  
High Energy ◽  
Bodyweight Gain ◽  
Low Energy ◽  
High Protein ◽  
Protein Diet ◽  
Daily Weight Gain ◽  
Protein Levels ◽  
Low Protein ◽  
Feed Costs

Grower ostriches that are fed more expensive diets with high energy and high protein to maximise growth can exhibit health problems. Despite this there is an ‘industry view’ that birds can be grown to slaughter weight within 8 months when high energy and protein diets are used, rather than 12–14 months using conventional diets. Given this scenario it is likely that there would be lower total feed costs associated with feeding a high energy and high protein diet for only 8 months compared with feeding a traditional diet for 12–14 months. The purpose of this experiment was to conduct an on-farm trial with grower ostriches (liveweight 48.7–50.0 kg) housed in a feedlot to examine their performance when subjected to four dietary treatments fed over 4 weeks: (i) treatment 1: birds fed a commercial grower diet with 10.7 MJ/kg and 138.0 g/kg of protein; (ii) treatment 2: birds fed a low energy (10.0 MJ/kg) and low protein (126.0 g/kg) diet; (iii) treatment 3: birds fed a high energy (12.5 MJ/kg) and medium protein (136.0 g/kg) diet; and (iv) treatment 4: birds fed a high energy (12.5 MJ/kg) and high protein (143.0 g/kg) diet in a feedlot. Birds fed on the low energy and low protein diet had the highest feed intake compared with the other treatments. Birds on treatment 2 also had a significantly higher (P = 0.01) daily weight gain (277.3 g/bird) compared with treatment 1 (50.9 g), treatment 3 (49.1 g) and treatment 4 (32.0 g), respectively. The results indicate that better daily bodyweight gain is likely if ostrich growers are fed with a lower energy and lower protein diet.

Effects of restrictions of energy, protein or both on growth and body composition of pigs

1977 ◽  
Vol 89 (3) ◽  
pp. 687-698 ◽  
Author(s):  
A. E. Carden ◽  
P. R. Goenaga
Keyword(s):  
Body Composition ◽  
Adipose Tissue ◽  
Weight Distribution ◽  
Live Weight ◽  
High Energy ◽  
Dietary Factors ◽  
Low Energy ◽  
High Protein ◽  
Control Group ◽  
Low Protein

SummaryAn experiment was carried out, using Duroc Jersey barrows, to test the hypothesis that relationships within the pig fat-free carcass remain unaltered when varying the principal dietary factors: energy, protein or both. Twelve pigs were assigned to each of the following diets: high energy-high protein (HEHP), used as control group; low energy-high protein (LEHP); high energy-low protein (HELP) and low energy-low protein (LELP). From 30 kg live weight onwards the animals were individually penned and fed once a day the experimental rations, on a restricted scale of feeding related to live weight. Compared with the control group, daily intake of metabolizable energy was approximately 37% lower in LEHP and LELP groups while daily protein intake was approximately 25% lower in HELP and LELP groups.In each group the 12 pigs were slaughtered between 60 and 110 kg. The right half carcasses were completely dissected using strictly anatomical criteria. The main growth characteristics of the four treatments were described by second degree polynomials fitted to the live weight-age data. Each treatment produced a characteristic growth curve. In every case significant differences were found in the polynomial coefficients. Data on body composition were subjected to analysis of covariance, using the linear model y = a + bx. When growth of different parts of a whole were studied the weight of that whole was used as the independent variable. When muscle:bone ratio was examined the weight of total side muscle was used as covariate in the covariance analysis for total side bone.The major treatment effects were on the relationship between fat and non-fat tissues in the carcass. Thus, in relation to dissected side weight, HELP animals had more fat and less muscle and bone than controls, while LEHP and LELP pigs had more muscle and bone and less adipose tissue. Within the fat-free carcass several differences were found on muscle weight distribution. LEHP, HELP and LELP pigs had a higher proportion of ‘expensive muscles’. However, the magnitude of these changes was small and likely to be of little commercial importance. On the other hand, only minor differences were found in bone weight distribution. These were confined to the scapula and femur. Muscle:bone ratio was not affected by the treatments. Within the adipose tissue differences were observed in growth rates from the different depots relative to total side fat. Thus, it would appear that the growth rate of the subcutaneous depot was higher and that of the intermuscular one lower in LEHP and LELP animals. The body cavity depot was less in these animals.

Effects of hormones and diets on performance and carcass characteristics of pigs during summer and winter

1970 ◽  
Vol 12 (1) ◽  
pp. 47-54 ◽  
Author(s):  
O. M. Hale ◽  
J. C. Johnson
Keyword(s):  
Carcass Characteristics ◽  
High Energy ◽  
Low Energy ◽  
High Protein ◽  
Energy Concentration ◽  
Dietary Energy ◽  
Low Protein ◽  
Dressing Percentage ◽  
High Protein Diets ◽  
Protein Diets

SUMMARYOne hundred and forty-four weanling Duroc barrows were individually fed to study effects of season (summer and winter), energy concentration of the diet (high and low), protein concentration (high and low), and orally administered hormones (none, diethylstilboestrol, and mefhyltestosterone) on performance and carcass characteristics of growing-finishing swine.In summer the rate of gain of pigs was 6% slower and yielded carcasses with 19% smaller loin-eye areas but 3% more lean cuts than in winter.Pigs fed on high-energy diets gained 13% faster, consumed 8% less feed daily and required 18% less feed per unit of weight gain than pigs fed on low-energy diets. Pigs fed on high-energy diets also had a dressing percentage 2·5 units higher and yielded carcasses 2% shorter, with 15% more backfat, than those fed on low-energy diets.Pigs fed on low-protein diets had a dressing percentage 1·6% higher and yielded carcasses with about 7% thicker backfat than pigs fed on high-protein diets. Dietary energy and protein concentrations interacted significantly in their effect on rate of gain. Pigs fed on low-energy, low-protein diets gained weight about 7% faster than pigs fed on low-energy, high-protein diets; however, pigs fed on high-energy, high-protein diets gained weight about 3% faster than pigs fed on high-energy, low-protein diets.The only significant effect of giving each pig about 2 mg of diethylstilboestrol (DES) per day was a 2% increase in weight of lean cuts. An average daily consumption of 20 mg methyltestosterone (MT) per pig decreased rate of gain, daily feed intake, dressing percentage and backfat thickness, but increased carcass length, area of the loin-eye and weight of lean cuts. Hormones and dietary energy levels interacted in their effects on rate of gain and feed efficiency. Pigs fed on low-energy diets with or without hormones gained weight at about the same rate, but high-energy diets increased rate of gain in pigs receiving no hormone or DES by about 17% and 21%, respectively, while having no effect in pigs receiving MT. Pigs fed on low-energy diets with MT required about 7% and 6% less feed per unit of gain than pigs fed on low-energy diets without hormone or with DES, respectively; whereas pigs fed on high-energy diets containing MT required about 10% and 14% more feed per unit of gain than did pigs fed on high-energy diets without hormone or with DES, respectively.

scholarly journals Hypothalamic responses to peripheral glucose infusion in food-restricted sheep are influenced by photoperiod

2005 ◽  
Vol 184 (3) ◽  
pp. 515-525 ◽  
Author(s):  
Z A Archer ◽  
S M Rhind ◽  
P A Findlay ◽  
C E Kyle ◽  
M C Barber ◽  
...  
Keyword(s):  
Gene Expression ◽  
Weight Maintenance ◽  
Plasma Concentrations ◽  
Insulin Receptors ◽  
Pulse Amplitude ◽  
Pulse Frequency ◽  
Hypothalamic Arcuate Nucleus ◽  
Maintain Body Weight ◽  
Gonadotrophin Releasing Hormone ◽  
Male Sheep

Nutritional feedback provided by systemic hormones, such as insulin and leptin, influences reproductive neuroendocrine output within the hypothalamus, yet the mechanisms and their interaction with photoperiodic cues remain unresolved in seasonal species. Here, peripheral glucose (G) infusion was used to increase endogenous concentrations of insulin and leptin in food-restricted sheep kept in either long-day (LD) or short-day (SD) photoperiod, and responses were examined in terms of pulsatile luteinising hormone (LH) (gonadotrophin-releasing hormone by inference) output and hypothalamic gene expression for nutritionally sensitive neuropeptides and receptors. We addressed the hypothesis that these hypothalamic responses were correlated and influenced by photoperiod. Oestradiol-implanted, castrated male sheep were kept 16 weeks in SD (8 h light/day) or LD (16 h light/day) and then transferred to the opposite photoperiods for 8 weeks, during which food was restricted to 90% requirement to maintain body weight (maintenance). For the final 6 days, food was reduced to 75% maintenance, and sheep in both photoperiods were infused intravenously with G (60 mM/h) or saline (S) (n=8/group). G-infused sheep had higher mean plasma concentrations of G, insulin and leptin than S-infused sheep, with no effect of photoperiod. In LD, but not in SD, G infusion increased LH pulse frequency and pulse amplitude. In LD, but not in SD, gene expression in the hypothalamic arcuate nucleus was lower in G- than S-infused sheep for neuropeptide Y (NPY) and agouti-related peptide (AGRP) and was higher in G- than S-infused sheep for pro-opiomelanocortin (POMC). Gene expression for leptin and insulin receptors was not affected by photoperiod or infusion. These results are consistent with the involvement of NPY, AGRP and POMC in mediating the reproductive neuroendocrine response to increased systemic nutritional feedback, and they support the hypothesis that hypothalamic responses to nutritional feedback are influenced by photoperiod in sheep.

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