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This experiment was conducted to determine the effects of molt-induction period on molting and post-molt performance of laying hens. White Leghorn hens at 64 weeks of age were used. After a 4-week preliminary period, they were divided into 5 groups (1 control and 4 treatment groups). The control-group hens were continuously fed a corn- and soybean-based layer ration ad libitum. In 1 of the 4 treatment groups, molting was induced by starvation for 2 weeks (MS group), and in the 3 others by ad libitum feeding of a molt diet (ME: 1.6Mcal/kg) based on rice hull, corn, wheat bran, and corn gluten feed for 2 (MF-2 group), 3 (MF-3 group), and 4 weeks (MF-4 group). During the post-molt production period, the hens were again fed the layer ration. During the molt-induction period, the heterophil: lymphocyte (H: L) ratio, the ovary and oviduct weight, and the energy intake were measured. Egg production, egg quality, body weight, and feed intake were measured throughout the experiment. During the treatment period, compared to the control group, the feed intake and body weight in the molted groups were significantly lower; the ovaries and oviducts of the hens in the molted groups were distinctly lighter (P < 0.01). On day 10 of molting, the H: L ratio in the MF groups was lower than that in the MS group. Additionally, egg production completely ceased within 6 d in the MS group and decreased to 3% at week 2 in the MF groups. No significant differences with regard to days required to regain 50% egg production were found between the MS and MF-3 groups. During the post-molt period, egg production and quality improved in the molted groups, the production in the MF-3 group was highest. We assume that ad libitum feeding of the molt diet for 3 weeks effectively induces molting and enhances post-molt production.

哺乳期のビタミンA給与量制限がブタの筋肉内脂肪蓄積に及ぼす影響について調査した．雌子豚10頭を2区に分け，生後3日齢から28日齢の哺乳期間中，養分要求量を満たす量を給与する区（対照区）とビタミンAのみ対照区の1/5量給与した区（低VA区）の2区に分けて授乳させ，生後28日齢でと畜した．低VA区の増体量は対照区とほぼ等しかった．また，低VA区の総血中脂質と筋肉内脂肪含量は対照区よりも低かった（P ＜ 0.001，P ＜ 0.01）．哺乳期におけるVA摂取量不足は，発育に影響を及ぼさずに，血清中脂質画分とIMF含量を低下させた．以上から，生後3日齢から28日齢のブタにおける哺乳期のビタミンA給与量制限は，筋肉内脂肪蓄積を減少させることが示唆された．

This study investigated the suitable metabolizable energy (ME) level of molt diet for hens that cease producing eggs without being subjected to great stress. During the preliminary period, White Leghorn hens were fed a corn-soybean meal-based layer ration ad libitum. After a 4-wk preliminary period, the hens were randomly divided into 3 treatment groups and 1 control group; the control group was persistently fed the layer ration. The 3 treatment groups were fed the following diets ad libitum for 4wk: (1) 100% molt diet based on corn, wheat bran, and corn gluten feed (ME 2.3Mcal/kg M100:); (2) 85% molt diet with 15% rice hull (ME 1.9Mcal/kg M85:); and (3) 70% molt diet with 30% rice hull (ME 1.6Mcal/kg M70:). During the post-molt period, the hens were returned to the layer ration. During the molting period, the heterophil: lymphocyte (H:L) ratio, ovary and oviduct weights, and MEn intake were measured. Egg production, egg weight, egg quality, body weight, and feed intake were measured throughout the experiment. During the molting period, the feed intake, body weight, and ovary and oviduct weights in the molted groups were significantly (P

This study aimed to evaluate the effects of a molt diet on molt induction and the post-molt performance of laying hens. White Leghorn hens (age, 62wk) were randomly divided into three groups (two experimental, one control). After a 4-wk preliminary period, one group (control) was continuously fed a corn-soybean-based layer ration ad libitum. Molting was induced in the other groups by starvation (MS) or with feed (MF). In the MS group, the feed was withdrawn for 2wk; this was followed by feeding of a layer ration on alternate days for 1wk and then ad libitum. The MF group was fed ad libitum a low-protein and low-energy diet based on corn, wheat bran, and corn gluten feed for 4wk; this was followed by ad libitum feeding of a layer ration. Egg production, egg quality, and feed intakes were measured throughout the experimental period; ovary and oviduct weights and heterophil: lymphocyte (H: L) ratios were measured during molting. During molting, the feed intake in the MF group was lower than that of the control; body weights of the molted groups were significantly reduced. Additionally, the MS group totally ceased egg production within 8 d; in the MF group, egg production decreased to 3.8% by d 10. On d 10 of molting, the H : L ratio of the MF group was lower than that of the MS group. On d 14, the ovaries and oviducts of the molted groups were distinctly lighter than those of the control. Throughout the post-molt period, egg production and egg shell thickness of the molted groups improved; but there were no significant differences. Additionally, the eggs of the MF group were heavier than those of the MS and control groups. This study suggests that feeding of a low-protein and low-energy diet effectively induces molting and increases post-molt production.

This experiment aimed to determine the effects of restricted feeding a molt diet on molt induction in laying hens. Single Comb White Leghorn hens (age, 61wk) were housed in individual cages and randomly divided into 3 groups (2 treatments and 1 control group). After a 4-wk preliminary period, the control group was continuously fed a layer ration based on corn and soybean meal ad libitum. Molting was induced in the treatment groups by starvation (MS) or with feeding (MF). In the MS group, the feed was withdrawn for 2wk; this was followed by feeding of the layer ration skip-a-day for 1wk and then ad libitum. The MF group was fed a low-protein and low-energy diet comprising corn, wheat bran, and corn gluten feed 60g/hen/d for 4wk; this was followed by ad libitum feeding of the layer ration. Egg production, egg quality, and feed intakes were measured throughout the experimental period; serum estradiol-17β concentration, heterophil: lymphocyte (H:L) ratio, ovary and oviduct weights, and MEn intake were measured during the molting period. During molting, body weights of the MS and MF groups were significantly (P

This experiment was carried out to compare the effect of early feed restriction of different regimens on subsequent growth performance, carcass composition, and lipid metabolism in male ducks. One hundred and twenty meat-type male ducks (White Pekin) were assigned to 4 treatments at 7 days of age, namely: ad libitum feeding (control), 50% of ad libitum intake, rice hull-diluted diet feeding, and skip day feeding. Ducks were restricted for feed between 8 to 14 days of age. During this period, dietary rice hull-treated group was given diet containing 11% CP and 1, 430 kcal ME/kg, whereas other treatment groups were offered diet containing 22% CP and 2, 900 kcal ME/kg. A commercial finisher diet for broilers (18% CP; 3, 180 kcal ME/kg) was resumed following feed restriction until 49 days of age. Compensatory growth was attained at 49 days of age irrespective of restriction regimens due largely to their fast growth rate with better nutrient utilization during recovery period. Carcass fat contents decreased in ducks fed 50% of ad libitum or diluted diet but not in those fed skip day feeding when compared with controls at 14 and 49 days of age. The activities of hepatic fatty acid synthetase (FAS) and acetyl-COA carboxylase (ACC) decreased in ducks fed 50% of ad libitum and fed diluted diet at the end of 7 days feed restriction and tended to further decrease at 49 days of age. Serum triacylglycerol concentrations also declined in ducks fed 50% of ad libitum or fed diluted diet at both 14 and 49 days of age. The results suggested that early feed restriction could be used to improve growth performance and carcass characteristic of meat-type ducks and diet dilution regimen may have an advantage for practical application in meat-type duck production.

1. Isolated hepatocytes from chicks were used to study the effects of pantethine supplementation to incubation medium on in vitro lipogenesis, CO2 production and beta-oxidation of fatty acid. 2. In vitro lipogenesis, determined by the incorporation of 1-[14C]acetate into total lipid and various lipid fractions, as depressed in concordance with the increase of pantethine concentration in the medium. 3. Incubation of isolated hepatocytes with pantethine resulted in a significant decrease (P < 0.01) in the activities of acetyl-CoA carboxylase and fatty acid synthetase. 4. The results suggest that in vitro fatty acid synthesis from 1-[14C]acetate was depressed and CO2 production was elevated in hepatocytes of chicks through pantethine addition to the medium at a low level.

To investigate the effect of driedBacillus subtilisculture on growth, body composition and hepatic lipogenic enzyme activity, female broiler chicks were fed on either no additive (control) or driedB. subtills-culture-supplemented commercial diets (215 g crude protein/kg, 12.85 MJ metabolizable energy/kg) at 10 or 20 g/kg diet for 28 d from 14 to 42 d of age. Body weight, and moisture, fat, protein and ash contents of the body were not influenced by theB. subtilisculture. Feed efficiency. N utilization, the ratio of abdominal fat or liver to body weight, acetyl-coenzyme A carboxylase (EC6·4·1·2) activity, liver and serum cholesterol contents were significantly lower in treatment groups, while fatty acid synthetase activity and serum cholesterol concentration were not significantly different, compared with the control group. Liver triacylglycerol concentration was decreased in chicks given 20 g culture·kg diet, while serum and carcass triacylglycerol concentrations were significantly lower in treatment groups than in the control group. Serum phospholipid concentration was increased but carcass phospholipid concentration was decreased in chicks given 20 gB. subtilis/kg diet, while liver phospholipid concentration was not significantly influenced. The advantages of inclusion ofB. subtilisto the broiler diet included improved feed efficiency, less abdominal fat, reduced triacylglycerol concentrations in the liver, serum and carcass and reduced cholesterol concentrations in the liver and carcass.

泌乳中ヤギに給与する飼料の変換が,皮下脂肪および乳腺組織における,脂肪酸合成能と脂肪酸合成関連酵素の活性,ならびに皮下脂肪組織における,リポプロティンリパーゼとホルモン感受性リパーゼの活性におよぼす影響を検討した.泌乳中のヤギ5頭(日本ザーネン種,体重35～46kg)を,3頭と2頭の2群に分けて供試した.第1群(3頭)は粗飼料のみを3週間給与した後,濃厚飼料多給に変換し,3週間飼育した.第2群(2頭)は,第1群と逆の処理を行なった.いずれの群においても,飼料を変換する1時間前に採血を,また直前に生検によって皮下脂肪組織と乳腺組織を,それぞれ1～2g摘出した.血清中グルコース濃度は,粗飼料給与時より濃厚飼料多給時の方が高く,一方,血清中遊離型脂肪酸濃度は,粗飼料給与時において高い値を示した.皮下脂肪組織における,脂肪酸合成能および脂肪酸合成関連酵素とリポプロティンリパーゼの活性は,粗飼料給与時に比べて,濃厚飼料多給時の方が高い値を示した.一方,ホルモン感受性リパーゼ活性は粗飼料給与時の方が高かった.乳腺組織における脂肪酸合成能は皮下脂肪組織に比べ著しく高い値を示したが,飼料変換による顕著な影響は観察されなかった.これらの結果から,泌乳中の反芻家畜への濃厚飼料多給による乳脂肪生産の低下の原因の1つは,乳腺組識での脂肪酸合成能の低下というより,血流中の脂肪酸および乳脂肪合成のための前駆物質が皮下脂肪組織の方向に流れ,乳腺組織へのこれらの取込みが減少するためであろうと推察される.

ヤギに給与する飼料を変換することによって,皮下脂肪組織における脂質合成能と脂肪酸合成関連酵素およびリポプロテインリパーゼとホルモン感受性リパーゼの活性にどのような影響があらわれるかについて検討した.乾乳中のヤギ6頭(日本ザーネン種,体重22～28kg)を,3頭づつの2群に分けて供試した.第1群は粗飼料のみを3週間給与した後,濃厚飼料多給に変換し,3週間飼育した.第2群は,第1群と逆の処理を行った.いずれの群においても,飼料を変換する1時間前に採血を,また直前に生検によって皮下脂肪組織と肝臓をそれぞれ1～2g摘出した.血清中グルコース濃度は,粗飼料給与時より濃厚飼料多給時の方が高く,一方血清中遊離型脂肪酸濃度は粗飼料給与時において高い値を示した.皮下脂肪組織における脂肪酸合成能および脂肪酸合成関連酵素とリポプロテインリパーゼの活性は,粗飼料給与時に比べて,濃厚飼料多給時の方が高い値を示した.一方ホルモン感受性リパーゼ活性は粗飼料給与時の方が高かった.これらの結果は,粗飼料給与時より濃厚飼料多給時の方が皮下脂肪組織への脂肪蓄積が増大することを裏付けているように思われる.肝臓における脂肪酸合成関連酵素の活性に対して飼料の変換による影響は観察されなかった.

炭水化物の配合量を変化させることにより,飼料中のエネルギー含量を増減させたときの鶏ヒナの肝臓における脂質合成能および脂肪酸合成に関与しているいくつかの酵素活性を検討した.肝臓中のトリグリセリド含量はME3200kcal/kgの飼料を,また全コレステロール含量はME1900kcal/kgの飼料を給与したヒナにおいて高い値を示した(P

The influence of increasing dietary protein level, at the expense carbohydrate, on alanine aminotransferase (AAT) activity in liver and kidney of growing chicks was investigated.Approximately 85% to 90% of AAT activity in kidney was associated with the particulate fraction and only 10% to 15% with the soluble fraction. In liver, approximately 65% to 80% of AAT activity was associated with the particulate fraction and 20% to 35% with the soluble fraction.Increasing dietary protein, at the expense of carbohydrate, resulted in a linear increase in AAT activity in the particulate fraction of liver and kidney, although the magnitude of change in kidney was greater than that observed in liver. AAT activity in the soluble fraction of kidney was significantly increased when the dietary protein level increased. On the other hand, AAT activity in the soluble fraction of liver tended to increase, although insignificantly, when the percentage of energy from dietary protein increased from 10% to 40%. However, chicks fed diet containing 60% energy from protein had significantly higher AAT activity in the soluble fraction of liver than those fed diets containing from 10% to 40% energy from protein.Activity of phosphoenolpyruvate carboxykinase in the particulate fraction of liver and kidney was not affected by the dietary protein level.

成長中鶏の飼料にパンテチンを添加することによって,血漿中の各脂質画分濃度および肝臓における脂質合成に及ぼす影響を検討した.コレステロール無添加および添加飼料にパンテチン200ppmを添加し,14日間飼育した時,成長中鶏の増体量,飼料摂取量および肝臓重量には大きな影響を及ぼさなかったが,腹腔内脂肪重量は低下する傾向を示した.コレステロール添加飼料を給与した鶏に比べて,コレステロール無添加飼料を給与した鶏では胆嚢重量が大きく,さらにコレステロール添加飼料にパンテチンを添加すると胆嚢重量は増大し,胆汁の分泌が促進されることが推察された.コレステロール無添加飼料給与に比べて,コレステロール添加飼料給与では肝臓中のトリグリセリドおよび総コレステロール含量は高い値を,リン脂質含量は低い値を示した.さらにトリグリセリド含量は両飼料にパンテチンを添加することにより,また総コレステロール含量はコレステロール添加飼料にパンテチンを添加することによって低下した.コレステロール無添加飼料給与に比べて,コレステロール添加飼料給与では血漿中のトリグリセリド,エステル型と遊離型コレステロールおよびLDL-コレステロール濃度は高い値を示した.またトリグリセリド濃度はユレステロール添加飼料にパンテチンを添加することによって,エステル型と遊離型コレステロール,リン脂質およびLDL-コレステロール濃度は両飼料にパンテチンを添加することによって低下した.肝臓での脂肪酸合成関連酵素であるACC活性はコレステロール添加飼料へのパンテチン添加,NADP-MDHおよびCCEの活性はコレステロール無添加飼料へのパンテチン添加によって低下した.またCCEおよびHMG-CoA還元酵素の活性は,コレステロール無添加飼料給与に比べて,コレステロール添加飼料給与の鶏の方が低い値を示した.そしてHMG-CoA還元酵素の活性は,コレステロール添加飼料にパンテチンを添加することによって増加した.以上の結果から,コレステロール添加飼料にパンテチンを添加することによる肝臓および血漿中コレステロール含量の低下は,肝臓におけるコレステロール合成の低下ではなく,胆汁を通してのコレステロール分泌の促進によるものと推察される.

The effects of dietary essential fatty acid deficiency on the rate of lipogenesis and activities of lipogenic enzymes of the liver were investigated in growing chicks.Compared with the control, chicks fed the tripalmitin-containing or fat-free diet had significantly higher liver triglyceride content. In contrast, chicks fed the EFA-deficient diets had significantly lower phospholipid content in the liver. The triglyceride and phospholipid concentrations in the serum were significantly higher in chicks fed the fat-free diets than in those fed the control diet. Likewise, chicks fed the tripalmitin-containing or fat-free diet had significantly greater total cholesterol, but significantly lower non-esterified fatty acids, concentration in the serum than the control birds.The rate of incorporation of acetate-1-14C into the fatty acids and glyceride-glycerol was significantly higher in chicks fed the tripalmitin-containing or fat-free diet than in those fed the control diet. On the other hand, chicks fed the tripalmitin-containing or fat-free diet had significantly decreased NADP-isocitrate dehydrogenase, but significantly increased glucose-6-phosphate dehydrogenase, activity in the liver. NADP-malic dehydrogenase activity in the liver was significantly higher in chicks fed the fat-free diet than in those fed the control diet.

コリン欠乏飼料およびメチオニンとビタミンB12の飼料への添加が北京ダック雛の成長および肝臓と血清中の脂質含量におよぼす影響を検討した。いずれのコリン欠乏区においても,ペローシスが観察され,また著しい成長遅延が見られた。コリン欠乏区では,肝臓中のトリグリセリド含量は増加し,リン脂質含量は低下する傾向を示した。血清中のトリグリセリド,総コレステロールおよびリン脂質濃度は,いずれのコリン欠乏区においても低下した。コリン欠乏飼料へのメチオニンとビタミンB12の添加は北京ダック雛の成長および肝臓と血清中の各脂質画分含量への影響は見られなかった。肝臓中リン脂質の組成は各処理区の間に大きな影響は観察されなかった。メチオニンあるいはビタミンB12を添加しても,アヒル雛の生体内においてコリンが充分に合成されないため,コリン欠乏飼料給与区は,いずれも対照区に比べて,血清中のトリグリセリドとリン脂質は低い値を示したものと思われる。

The changes in the concentrations of various plasma and liver lipid fractions, plasma E2 and corticosterone, and hepatic lipogenic related enzyme (LRE) activities, were determined. The relationships between the concentrations of these plasma hormones and hepatic lipoge-nesis around the onset of egg production were elucidated.E2 concentration rose gradually as the hens advanced in age, reaching a peak at the age of 150 days which was the period immediately before the onset of egg laying. Triglyceride, NEFA, total cholesterol and phospholipid levels in the plasma remained relatively constant between 90 and 140 days of age. These rose rapidly as the birds neared the age of 150 days, and reached their peaks immediately before the onset of laying. These values decre-ased, and then remained stable, upon the onset of egg production; nevertheless, even at their reduced levels, they were still comparatively higher than these obtained during the 90-140 days of pre-ovulation period.Hepatic triglyceride content rose gradually and simulataneously with the aging of the hens and reached a peak immediately before the onset of laying. It decreased when the egg laying set in, but remained at a relatively higher level thereafter.The activities of hepatic LREs increased gradually as the hens advanced in age. Fatty acid synthetase reached a peak at 130 days of age and citrate cleavage enzyme and NADP-malate dehydro-genase, 140 days of age.Statistically significant positive correlations were observed between plasma E2 concentra-tion and the grouped parameters of abdominal fat weight (P

Effects on dietary pantethine supplementation on hepatic lipid accumulation and on the activities of lipogenic-related enzymes in the liver were studied in Single Comb White Leghorn laying hens fed isocaloric and isonitrogenous diets containing corn or barley as the carbohydrate source. Addition of 200 ppm pantethine to the corn-soy (CS) basal diet significantly reduced abdominal fat weight, liver triglyceride, as well as total cholesterol and 17 beta-estradiol concentrations in the plasma. Activities of citrate cleavage enzyme (EC 4.1.3.8; CCE) and fatty acid synthetase (FAS) in the liver were significantly reduced when the CS basal diet was supplemented with pantethine, but the activities of nicotinamide adenine dinucleotide phosphate-malate dehydrogenase (EC 1.1.1.40; NADP-MDH) and glucose-6-phosphate dehydrogenase (EC 1.1.1.49; G6PDH), were not significantly affected. However, liver triglyceride, total cholesterol, and 17 beta-estradiol concentrations in plasma as well as the activities of CCE, FAS, and NADP-MDH in liver were significantly lower in laying hens fed the barley-soy (BS) basal diet than in those fed the CS basal diet. Pantethine supplementation to the BS diet failed to show any significant effect on liver triglyceride content and on the hepatic activities of lipogenic-related enzymes. There were no significant differences in liver weight, rate of egg production, and egg weight among dietary treatments. these results suggest that dietary pantethine is effective in reducing the accumulation of liver and abdominal fat in laying hens fed a CS diet.