Effect of sex on lipogenic activity in swine adipose tissue

Adipose tissue was obtained from male, female and male pigs castrated either at birth, 2 or 4 mo of age. Pigs were biopsied at 11 and 20 wk of age to obtain adipose tissue samples. Lipogenic capacity was assessed by measurement of in vitro glucose incorporation into lipids of adipose tissue slices. At 20 wk of age, males were less fat than females or males castrated either at birth or 20 mo of age. Adipocyte volume at 20 wk of age was smaller in males, females and recently castrated males (4 mo) than males castrated at birth or 2 mo of age. Lipogenic rate at 20 wk of age was lower in males than in castrated pigs; females had intermediate lipogenic rates. The results provide a partial metabolic explanation for the difference in subcutaneous fat deposition in the sexually diverse groups. There was no effect of estradiol-17 beta or testosterone in vitro on adipose tissue lipogenesis, suggesting that sex hormone effects in vivo may not be involved in short-term regulation of lipogenesis.     

Effects of body condition score at parturition and postpartum supplemental fat on adipose tissue lipogenic activity of lactating beef cows

Three-year-old Angus x Gelbvieh beef cows nutritionally managed to achieve a BCS of 4 +/- 0.07 (479.3 +/- 36.3 kg of initial BW) or 6 +/- 0.07 (579.6 +/- 53.1 kg of initial BW) at parturition were used in a 2-yr experiment (n = 36/yr) to determine the effects of BCS at parturition and postpartum lipid supplementation on cow adipose tissue lipogenesis. Beginning 3 d postpartum, cows within each BCS were randomly assigned to be fed hay and a low-fat control supplement or supplements with either cracked high-linoleate safflower seeds or cracked high-oleate safflower seeds until d 60 of lactation. Diets were formulated to be isonitrogenous and isocaloric, and safflower seed diets provided 5% DMI as fat. Adipose tissue biopsies were collected near the tail-head region of cows on d 30 and 60 of lactation. Dietary treatment did not affect (P > or = 0.43) adipose tissue lipogenesis. Body condition score at parturition did not affect acetate incorporation into lipid (P = 0.53) or activity of acetyl CoA carboxylase (P = 0.77) or fatty acid synthase (P = 0.18). Lipoprotein lipase activity and palmitate incorporation into triacyl-glycerol tended to be greater (P = 0.06), and palmitate esterification into total acylglycerols was greater (P = 0.01) in cows with a BCS of 4 at parturition. Mean activity of acetyl-CoA carboxylase (P < 0.001), lipoprotein lipase (P = 0.01), and rate of palmitate incorporation into monoacylglycerol (P = 0.02), diacylglycerol (P = 0.001), triacylglycerol (P = 0.003), and total acylglycerols (P = 0.002) were greater at d 30 than d 60, suggesting a greater proclivity for fatty acid biosynthesis and esterification by adipose tissue at d 30 of lactation. Although dietary lipid supplementation did not affect adipose tissue lipogenesis, results suggest that cows with a BCS of 4 at parturition have a greater propensity to deliver exogenously derived fatty acids to the adipocyte surface and incorporate preformed fatty acids into acylglycerols as stored adipocyte lipid. Additionally, cows in early lactation seemed to be able to synthesize and incorporate more fatty acids into stored lipid than cows during peak lactation.     

Changes in activities of lipogenic enzymes in adipose tissue and liver of growing goats.

The lipogenic capacity of omental adipose tissue and liver was measured in vitro from samples obtained at slaughter from 33 young male goats. The animals were slaughtered either on the day of weaning (d 0) or 2, 14, or 56 d after weaning. Ages at weaning were 4 wk (early weaning) or 6 or 8 wk (late weaning). Blood samples from the jugular vein were taken before slaughter to measure the concentrations of plasma glucose and nonesterified fatty acids. There was a 30% decrease in glucose concentration after weaning. Nonesterified fatty acid concentration increased fourfold between d 0 and 2 after weaning. By d 14 after weaning, nonesterified fatty acids returned to basal concentration. The lipoprotein lipase (LPL) activity of adipose tissue declined markedly (90%) on d 2 after weaning. Lipoprotein lipase activity returned to preweaning values by d 56 after weaning in those goats that had ad libitum access to feed. In adipose tissue, nicotinamide adenine dinucleotide phosphate (NADP)-malate dehydrogenase activity fell by only 17% by d 2 after weaning and to 63% by d 14 after weaning. Lipoprotein lipase activity was closely related to metabolizable energy intake the day before slaughter. Acetyl-coenzyme A carboxylase activity was low in adipose tissue and it increased only slightly by d 56 after weaning. The data indicated that LPL played a preponderant role in the restoration of lipid stores after weaning. High NADP-malate dehydrogenase activity together with a high concentration of plasma glucose by d 56 after weaning suggested that this enzyme activity could be enhanced by high glucose availability in goat kids. Activities of lipase, acetyl-coenzyme A carboxylase, NADP-malate dehydrogenase, and glucose-6-phosphate dehydrogenase in liver were essentially unaffected by weaning. The extent and rapidity of change of lipogenic enzymes of goat kids was much more pronounced in adipose tissue than in liver.     

Effect of nutritional status on swine adipose tissue lipolytic activities

Young swine (28 days of age) were fed an isocaloric and isonitrogenous diet with either a high fat or a low fat content for 3 to 4 weeks. The adipose tissue lipolytic rate was higher in the group fed the high fat diet. However, there was no effect of diet on the activities of several of the enzymes controlling the lipolytic process, i.e., adenylate cyclase, phosphodiesterase and hormone-sensitive lipase. No effect of diet on the activity of lipoprotein lipase was detected. Fasting for 72 hr, but not for 24 or 48 hr, caused an increase in the lipolytic rate. There was also a decrease in cell size after a 72-hr fast (P greater than .05) such that the increased rate was not significant when the data were expressed on a cell basis. Inexplicable transient changes in adenylate cyclase activity, as well as a decrease in the activity of the low affinity phosphodiesterase (doubtful physiological significance), were detected during starvation. Starvation depressed the adipose tissue lipoprotein lipase activity but had no effect on the hormone-sensitive lipase activity.     

Lipopigment in the adipose tissue of slaughtered swine

After feeding rests of slaughtered poultry together with whey, tapioca and residues of stark production to pigs 70% of the slaughtered pigs were refused by the meat inspection because of yellow fat and yellow hair. The occurrence of bile pigment, carotenoids and synthetic colours could be excluded while acid fast pigments were demonstrated in the fat tissue, liver and skeleton muscle. This could be confirmed by the peroxide number, acid number and the content of malondialdehyde and vitamin E. The results were discussed in the view of meat inspection laws.     

早期断奶对猪生产性能的影响

通过综述早期断奶对仔猪的消化吸收和免疫抗病,对母猪的发情、受胎、产仔以及繁殖寿命的影响,提示在研究和应用早期断奶技术时,要充分遵循生物学规律,才能取得最大限度的经济效益。     

Effect of chicken egg yolk antibody against adipose tissue plasma membranes on carcass composition and lipogenic hormones and enzymes in pigs

Chicken egg yolk antibody against pig adipose tissue plasma membranes (AIgY) was raised and used in the present experiment to evaluate the effect of dietary AIgY supplementation on pig growth and carcass composition. 160 crossbred (Duroc–Jersey × Landrace·Meishan) pigs, with initial live body weight of 27.5 ± 2.4 kg, were treated with AIgY or non-immunized control egg yolk powder (NIgY) at the inclusion level of 75 mg/kg diet. Following a 104-day trial, the pigs were slaughtered for analyzing the carcass and meat quality traits. The perirenal, mesenteric and subcutaneous fat depots were weighed and the diameter of adipocytes from different fat depots was measured with histological methods. Serum concentrations of insulin and leptin as well as the activities of malic enzyme (ME) and lipoprotein lipase (LPL) in adipose tissue were measured. Dietary supplementation of AIgY enhanced average daily gain and feed efficiency by 13.03% (P < 0.01) and 7.49%, respectively, with no influence on feed consumption. AIgY increased the lean mass by 10.3% (P < 0.01) without affecting the dressing percentage. Backfat thickness at 6th–7th rib and the weights of perirenal, mesenteric and subcutaneous fat depots were reduced by 24.14% (P < 0.01), 27.27% (P < 0.05), 20.42% (P < 0.01) and 29.21% (P < 0.01), respectively. Dietary supplementation of AIgY reduced the size of adipocytes in all the three fat pads (P < 0.05). The meat color was improved whereas the marbling score, the intramuscular fat content, and pH₄₅ of the longissimus muscle remained unaffected. Serum concentration of non-esterified fatty acids (NEFA) was significantly increased (P < 0.01) while urea-N content was reduced (P < 0.05). No alterations were detected for the serum levels of triacylglycerides (TG) and glucose. Serum concentrations of insulin and leptin were decreased by 26.19% (P < 0.05) and 26.53% (P < 0.05), respectively. LPL activity in adipose tissue was depressed significantly (P < 0.05) without affecting ME activity. This study demonstrates that dietary supplementation of AIgY can effectively improve growth and carcass composition of pigs and the changes of serum insulin and leptin levels as well as the tissue LPL activity may be involved in the acting mechanism.     

Behavior of back fat thickness, the activity of NADP-dependent dehydrogenases from adipose tissue and adipose tissue constituents fat and protein and their evidence for energy metabolism in dairy cows

Studies were conducted into 60 Friesian dairy cattle in the GDR for determination of dorsal fat thickness (DFT), activities of glucose-6-phosphate dehydrogenase (GPDH) and isocitrate dehydrogenase (ICDH) in adipose tissue, concentrations of fat and protein in adipose tissue, 2 weeks ante partum as well as 0, 2, 4, 6, 8, 12, 16, 20, 28, 36 weeks post partum, and liver fat levels, 2 and 4 weeks post partum. DFT, ICDH, GPDH, ICDH-GPDH ratio, fat level, fat-protein quotient, changes in DFT, GPDH, and fat-protein quotient exhibited significant relations with the weeks of lactation. The above 60 experimental cows were subdivided by 6 groups of half-siblings consisting of 10 animals each. Significant differences were found to exist between these groups of half-siblings with regard to DFT, GPDH, ICDH-GPDH ratio, and fat-protein quotient. Within each of the half-sibling groups, significant differences were found to exist between individuals for DFT, ICDH, GPDH, ICDH-GPDH ratio, and fat-protein quotient. The above parameters can be used to describe the energy metabolism of dairy cow via quantitative and temporal curves of fat mobilisation and fat deposition. In the context of both animal health and breeding, more attention should be given to determination of mobilisation and deposition of fat as well as to the post partum energy deficit.     

Effect of limited feed intake on growth of subcutaneous adipose tissue layers and on carcass composition in swine

Little is known about the function of individual backfat layers in swine. Our objective in this study was to evaluate differential growth of each backfat layer in pigs fed different amounts of the same diet. Relationships of growth of backfat layers to deposition of carcass protein and ether extract were also studied. Feed intake levels were ad libitum, 92.5% of ad libitum, and 85% of ad libitum for 36 barrows averaging 95 d of age and 37.8 kg of weight at the start of the study. Chemical composition of the carcass soft tissue was determined at the end of the 84-d study. Daily gain tended to decrease (P less than .10) and conversion of feed to gain improved (P less than .15) as feed intake decreased. The daily depositions (g/d) of protein and ether extract were 62.9 and 205 for the ad libitum group, 61.1 and 176 for the 92.5% intake group, and 59.3 and 153 for the 85% intake group, respectively. The compositional effect of limiting feed intake for 84 d was to produce less carcass soft tissue of greater lean content. Overall backfat depths were 31.5, 29.6, and 27.8 mm for the ad libitum, 92.5, and 85% intake groups, respectively. The outer backfat layer differed among groups; the 92.5 and 85% groups were thinner than the ad libitum group. Relative to the ad libitum group, the change in depth of the middle backfat layer was 86 and 75% for the 92.5 and 85% intake groups (P less than .01). The inner backfat layer was not affected significantly by level of feed intake.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of starter feeding program on growth performance and gains of body components from weaning to market weight in swine

Three experiments were conducted to test the hypothesis that different starter feeding programs (High, high quality; Low, low quality) will affect growth performance and body composition of pigs from weaning to market weight and that this effect may be influenced by gender (barrows or gilts) and breed (F, Yorkshire-Duroc x Hampshire; P, PIC Camborough 15 x PIC line 405). In Exp. 1, 21 +/- 4-d-weaned F pigs (n = 90) were used in a 2 (High or Low) x 2 (barrows or gilts) factorial design. In Exp. 2, 21 +/- 3-d-weaned pigs (n = 184) were used in a 2 (F or P) x 2 (High or Low) x 2 (barrows or gilts) factorial design. In Exp. 3, 21 F pigs from each gender and feeding program treatment were killed at d 0, 3, 7, 14, 42, 82, or 152 postweaning for evaluating body composition. Two starter feeding programs (High or Low) were applied to pigs for 6 wk postweaning. Pigs from both High and Low treatments were provided the same corn-soybean meal-based diets for the growing and finishing periods. Although the ADG of all pigs receiving the High treatment during the early starter period were higher (P < .01) than those of the Low, the terminal BW of F barrows were similar between High and Low (Exp. 1 and 2) and those of gilts were similar between High and Low (Exp. 2) (P > .80). However, the BW of P pigs receiving the High treatment, regardless of gender, tended to be heavier than those receiving the Low (Exp. 2) and F barrows receiving the High treatment tended to be heavier than those receiving the Low (Exp. 1). For the first 7 d postweaning, the High-fed pigs gained more protein (P < .05) and lost less fat (P < .05) than Low-fed pigs. During the growing-finishing period, the Low-fed pigs exhibited compensatory protein gain and achieved a body protein content similar (P < .60) to High-fed pigs by termination. Protein gains from weaning to termination between High- and Low-fed pigs were not different in Exp. 2 and 3. The protein gain of gilts was higher (P < .05) than that of barrows. Similarly, fat gain within genders was not affected by starter feeding program. Fat gain of gilts, however, was lower (P < .08) than that of barrows in Exp. 3. In conclusion, the nutritional quality of the starter feeding program affected growth performance immediately after weaning but did not affect protein gain over the entire production period.     

Effect of dietary concentrations of fat and energy on fat deposition in broilers divergently selected for high or low abdominal adipose tissue

1. Fat deposition in abdominal, mesenterial, sartorial and gizzard adipose tissues (AT), liver, breast muscle, skin and carcase was studied in male broilers, selected for high (HF) and low (LF) abdominal fat and fed on diets differing in energy density and total fat content. 2. There were no significant differences in body weight in the experimental groups. The relative weight (g/kg body weight) of the dissected adipose tissues was higher in HF than in LF birds. Fat concentration in the AT (sartorial excepted), skin and body was higher in the HF compared with the LF birds. The lines did not differ significantly in liver and breast muscle fat content. 3. Abdominal AT was affected by selection or dietary fat more than other AT and total body fat. 4. In the HF birds increasing energy density from 12.3 to 13.4 MJ/kg (dietary fat kept constant: 5.46 g/MJ) significantly increased the weight of the abdominal, mesenterial and sartorial AT. Increasing dietary fat (at both energy densities) decreased the weight of the AT, whereas increasing both energy and fat did not affect it. In the LF birds, similar but milder and insignificant trends were observed. It is suggested that this interaction has biological significance.     

Alterations with age in composition and lipolytic activity of adipose tissue from male and female chickens

The composition and lipolytic activity of adipose tissue from male and female chickens between 4 weeks of age and maturity was studied. The triglyceride to DNA ratio doubled in male adipose tissue during this time but increased seven‐fold in females, suggesting that the latter had larger adipocytes. The protein to DNA ratios were constant throughout.

The lipolytic sensitivity of adipocytes to glucagon did not alter with age but the concentration of glucagon producing a maximal response decreased. Noradrena‐line sensitivity, never very great, was lost after 16 weeks but re‐appeared in the adult male. The total lipolytic response of the tissue decreased, in terms of the dry weight (representing triglyceride content), but was constant in terms of the DNA content of the tissue, suggesting that the cell protoplasm was equally active at all ages from 12 weeks to maturity.     

Assessment of body fat in the pony: part I. Relationships between the anatomical distribution of adipose tissue, body composition and body condition

Reasons for performing study: Evaluation of equine body fat content is important for nutritional and clinical purposes. However, our understanding of total body fat and its regional distribution in the body is sparse. Currently, body fat evaluation relies on the subjective assessment of body condition score (BCS), which has never been validated against ‘gold standard’ chemical analysis or dissection measurements in ponies. Objectives: To define the relationships between subjective (BCS), objective (morphometric) indices of body fat and ‘gold standard’ measurements of actual body composition. Hypotheses: BCS and morphometry offer valid, noninvasive methods for determination of body fat in equids. Methods: Seven mature (mean ± s.e. 13 ± 3 years, 212 ± 14 kg, BCS 1.25–7/9), Welsh Mountain pony mares, destined for euthanasia (for nonresearch purposes), were used. For all ponies, body mass (BM), BCS and various morphometric measurements were recorded. Following euthanasia, all ponies were systematically dissected. Discrete white adipose tissue (WAT) depots were independently described. Gross, body chemical composition was determined by proximate analyses. Results: Total somatic soft tissues increased linearly (r²= 1.00), whereas body WAT content (1–26% live BM) increased exponentially (r²= 0.96), with BCS. WAT was equally distributed between internal and external sites in all animals irrespective of BCS. Nuchal fat was a poor predictor of total WAT (r²= 0.66). Periorbital WAT did not alter with BCS (r²= 0.01). Heart girth:withers height and ultrasonic retroperitoneal fat depth were closely associated with total, chemically‐extracted lipid which comprised 1–29% live BM (r²= 0.91 and 0.88, respectively). Conclusions and potential relevance: The exponential relationship between BCS and total body WAT/lipid suggests that BCS is unlikely to be a sensitive index of body fat for animals in moderate‐obese states. Morphometric measurements (body girths and retroperitonel fat depth) may be useful to augment subjective BCS systems.     

纱棘提取物对断奶仔猪生长和脂肪代谢的影响

试验选用(28±2)日龄东北民猪和"长×大"二元杂交断奶仔猪各24头,分别随机分为两个处理组,每组3个重复,每个重复4头猪(公母各半).试验组添加1 000 mg/kg沙棘提取物,研究沙棘提取物对断奶仔猪生产性能和脂肪代谢的影响.结果表明:①沙棘提取物对东北民猪和"长×大"猪平均日增重和料重比的影响不显著(P>0.05);②沙棘提取物提高了民猪试验组血清GH水平,降低了民猪试验组的血清TC、LDL、HDL含量和"长×大"猪血清INS水平.