茶多酚对蛋鸡生产性能、脂类代谢及蛋品品质的影响

本研究进行了两次饲养试验。试验一选用225羽37周龄罗曼蛋鸡随机分为5个处理,在试验基础日粮中分别添加0%、0.05%、0.1%、0.2%、0.4%茶多酚（纯度40%）,试验期59天;试验二选用600羽51周龄罗曼蛋鸡随机分为4个处理,分别在试验基础日粮中添加0%、0.025%、0.055%、0.1%茶多酚（纯度40%）,试验为期8周。探讨了茶多酚对蛋鸡生产性能、脂类代谢、蛋品质量的影响。结果表明：（1）日粮中添加不同剂量茶多酚对蛋鸡产蛋率和饲料利用率有一定的改善,但未见随茶多酚添加水平的升高而提高的趋势。（2）日粮中添加0.1%茶多酚可提高蛋黄中V_E58.99%、V_A20.96%,添加0.025%茶多酚降低蛋黄中胆固醇35.28%,茶多酚对全蛋中含硫氨基酸有增高趋势,重金属指标符合无公害鸡蛋要求;产蛋后期日粮中添加0.025%~0.1%茶多酚可降低破软蛋率31.59%~47.09%。（3）日粮中添加0.4%茶多酚分别降低46周龄蛋鸡血清总胆固醇19.65%、甘油三酯19.99%、低密度脂蛋白7.69%,提高高密度脂蛋白45.35%;但添加0.025%~0.1%茶多酚对59周龄蛋鸡血脂指标未见显著影响。     

Protein quality of some Nigerian traditional diets based on the African yambean (Sphenostylis stenocarpa) and pigeon pea (Cajanus cajan)

The protein quality of Nigerian traditional diets based on the African yambean (AYB) and pigeon pea (PP) were performed by in vivo and in vitro bioassays. The individual foods were processed, cooked, dried and mixed to resemble the traditional diets. Weanling male Wistar rats (45–55 g) were used for the bioassay. The rats were fed ad libitum for 35 days of which 28 days were for growth and 7 days for N-balance. All the eleven diets including casein (control) provided 1.6 g N/100 g diet. The parameters tested include PER, growth, N-balance, BV, NPU and apparent digestibility (AD). The rats fed the AYB diets, except AYB: Agidi (Ag), showed superiority in most of the parameters tested. There were significant positive correlations between PER and NPU (r=0.925;p<0.001); PER and AD (r=0.908;p<0.001); PER and body weight gain (r=0.969;p<0.001). The in vitro protein digestibility of the diets was significantly correlated (r=0.80;p<0.01) with the in vivo apparent digestibility. These parameters were used to rank the various diets. Crayfish protein was a better supplement to legume/cereal or legume starchy staple mixtures than leguminous oil seed. However, supplementation of PP: steamed corn (SC) diet with crayfish did not prove beneficial. The result showed that diets based on the African yambean, an under-exploited legume, are nutritious. The need for its reintroduction into the fare of the populace through increased production and appropriate processing technology is stressed. The results of this study can form a base for the standardization of Nigerian diets based on these legumes.     

保健砂对文昌鸡产蛋性能及蛋壳品质的影响

为探讨保健砂在蛋鸡生产中的合理应用,将450只文昌鸡（24周龄蛋鸡）随机分为5组,每组90只。对照组饲喂基础日粮和添加剂,试验组饲喂基础日粮、添加剂和保健砂,各试验组添加比例分别为2％、4％、6％和8％。同期对照组与试验组Ⅳ的产蛋率、料蛋比差异均显著（P<0.05）,对照组与试验组Ⅰ、Ⅱ、Ⅲ的产蛋率、料蛋比差异不显著（P>0.05）,平均蛋重、蛋壳厚度以及破损率各试验组与对照组对比差异均不显著（P>0.05）。试验结果说明饲料中添加4％～6％保健砂,有助于提高文昌鸡的产蛋率、减少饲料消耗,提高养鸡生产经济     

Blue Corn Tortillas: Effects on Learning and Spatial Memory in Rats

Consumption of pigmented corn has been associated with health benefits due to its flavonoid contents (mainly anthocyanins) and antioxidant ability. Therefore, the objective of this study was to determine the effect of blue corn tortilla (BM) consumption on memory and learning ability adult rats. Eighteen adult female rats were divided into three groups and fed for 38 consecutive days with commercial food (Control group) or the commercial food plus 6 g/day of either blue corn (BM) or white corn (WM) tortillas. Memory and learning capabilities were assessed using Barnes’s labyrinth at the end of the feeding period. Short-and long-term memory was improved in the BM group, showing that consumption of blue maize tortillas improves learning and memory capabilities in adult rats.     

Performance,milk fatty acid composition and behaviour of high-yielding Holstein dairy cows given a limited grazing period

The effects of a limited grazing period on the performance, behaviour and milk composition of high-yielding dairy cows were examined. A total of 56 Holstein cows yielding 44.7 ± 0.42 kg/day were allocated to one of four treatments in one of two, 4-week periods. Treatments were as follows: control (C)—cows housed and offered TMR ad libitum; early grazing (EG)—cows grazed for 6 hr after morning milking then housed; delayed grazing (DG)—cows returned to housing for 1 hr after morning milking followed by grazing for 6 hr, then housed; restricted TMR (RT)—cows grazed for 6 hr after morning milking, then housed and fed TMR at 75% of ad libitum. Intake of TMR was highest in cows receiving C, intermediate in EG and DG, and lowest in RT at 26.9, 23.6, 24.7 and 20.3 kg DM/day respectively. Pasture intake was similar in cows receiving EG or DG, but was higher in RT at 2.4, 2.0 and 3.5 kg DM/day respectively. Milk yield was similar between cows receiving C, EG or DG, but lowest in RT at 45.7, 44.2, 44.9 and 41.7 kg/cow, respectively, while milk fat content of C18:3 n-3 was increased by grazing. Cows in C spent more than 55 min/day longer lying and had three additional lying bouts/day, while lying bouts were shorter than for cows receiving EG, RT or DG. It is concluded that high-yielding cows can be grazed for 6 hr/day with little impact on performance, provided TMR is available ad libitum when housed.     

黄秋葵叶粉对海兰褐蛋鸡部分生产性能及蛋品质的影响

研究了黄秋葵叶粉对产蛋高峰期海兰褐蛋鸡部分生产性能和蛋品质的影响，旨在找出最适宜添加量，为进一步开发新型天然饲料添加剂奠定基础。试验组黄秋葵叶粉添加量分别为3％（T3）、4％（T4）、5％（T5）、6％（T6），对照组为不添加黄秋葵叶粉组（0％，T0）。试验共进行12周，预饲期1周。结果表明：试验组蛋重较对照组均有不同程度的提高，T3、T4组的产蛋率、产蛋量比对照组有所提高，T4、T5组采食量和T4组的料蛋比较对照组有所降低；各试验组在试验鸡蛋黄的着色效果均较对照组有显著提高（p＜0.05）；各试验组哈     

Effect of silymarin on metabolic factors of food-restricted over conditioned Wistar rats

This study was conducted to evaluate the changes in serum metabolic factors of over conditioned pregnant rats treated with silymarin in food restriction condition. Sixty pregnant Wistar rats were divided into five equal groups. All rats received high energy diet before treatments. Control group were fed ad libitum (Non-FR). Rats in other groups received 50% of the food intake of Non-FR group and served as food-restricted (FR) groups. Three of five FR groups received 150, 200 and 400 mg kg(-1) silymarin, respectively (FR-150, 200, 400). Another FR group (FR-Con) and the Non-FR group did not receive any silymarin. Glucose, triglyceride, LDL and HDL cholesterol, total cholesterol, thyroid hormones and cortisol were measured in serum. All factors were significantly different between groups except free-T4 and T4. Serum glucose concentrations in FR-150 and 200 and Non-FR groups were lower than FR-Con and FR-400. Silymarin significantly increased serum triglycerides, LDL cholesterol and cholesterol contents in FR groups. The highest levels of these factors were noted in 200 mg silymarin-treated group. HDL cholesterol was highest in FR-Con; meanwhile FR-200 group had the lowest HDL cholesterol. Serum cortisol decreased in treated and untreated FR groups except FR-150 group. Free-T3 and T3 concentrations in FR-400 and FR-Con groups were higher than the other silymarin treated groups. In conclusion our results indicate that 200 mg kg(-1) of silymarin in Wistar rats is the best dosage to achieve metabolic benefits. Silymarin has positive effects on lipid metabolism and can modulate serum triglyceride and cholesterol concentrations in food restriction condition. Also, the present findings suggest that silymarin under food restriction situation exerts a decreasing effect upon peripheral conversion of T4 to T3.     

Effect of short term ingestion ofTelfaria occidentalis (fluted pumpkin) on the liver

Four groups of female mice (18–22g) were fed for at least 10 days on a control diet or diets with addedTelfaria occidentalis (10% w/w) vegetables. Group 1 were the control animals. Group 2 were fed the vegetable diet alone. Group 3 were fed the control diet and injected with aflatoxin B₁(AFB₁, 0.35 mg/kg/day) in the last 3 days. Group 4 were fed with the vegetable diet and similarly treated for 3 days with AFB₁. No effects attributable to treatment were encountered in body weight, food intake, water intake and relative liver weight (g/100 g body weight). Decreases (17–40%) in PB sleeping time in the vegetable fed animals were not significant (P>0.05) in comparison to the control. Microsomal proteins increased by 2 fold in group 2 but were apparently normal in groups 3 and 4. In group 2 the activities of liver microsomal glucose-6-phosphatase and NADH-cytochrome c reductase increased but those of NADPH-cytochrome c reductase and aniline hydroxylase decreased. Increases were observed in the activities of all of these enzymes in groups 3 and 4. The highest increases were observed in glucose-6-phosphatase activity in mice fed the vegetables and also injected with AFB₁.     

Tocotrienol and fatty acid composition of barley oil and their effects on lipid metabolism

Barley oil was extracted with hexane from the grain of a high oil waxy hull-les barley. Twelve male broiler chicks were fed corn-based diets with either 10% barley oil, 10% corn oil or 10% margarinead libitum for ten days. Total plasma cholesterol concentration of the chicks fed barley oil was 34% lower (p<0.05) than that of the chicks fed margarine. Plasma low density lipoprotein cholesterol concentration of chicks fed barley oil was 53% and 59% lower (p<0.05) than those of chicks fed corn oil and margarine, respectively. Plasma high density lipoprotein cholesterol and triglyceride concentration of the barley oil group were similar to those of the margarine but higher (p<0.05) than those of the corn oil group. Chicks fed the barley oil gained more (p<0.05) body weight than those fed the corn oil and margarine. Barley oil had an effect in suppression of TC and LDLC in chicks compared to margarine. Barley oil supressed LDLC but not HDLC in chicks compared to corn oil. A greater weight gain of the chicks fed barley oil suggested that these chicks had normally functioning digestion and absorption. -Tocotrienol and -tocotrienol content of the barley oil were 24 and 17 times greater, respectively, than those observed in the corn oil, while the same fractions were not detectable in the margarine. Polyunsaturated fatty acid content of the barley oil was more than threefold that of margarine. These data suggest that -tocotrienol and polyunsaturated fatty acids are hypocholesterolemic components in barley oil.Contribution No. J-2617, Montana Agricultural Experiment Station. This research was supported, in part, by grants from the Montana Wheat and Barley Committee, Great Falls, MT and Ross Laboratories, Columbus, OH.     

An evaluation of a high-quality grass silage for milk production

Forty British Friesian cows with a mean calving date of 28 January were used in a randomized block design experiment to evaluate a high-quality grass silage for milk production. The high-quality silage was made from two consecutive cuts of a perennial ryegrass sward after regrowth intervals of 37 days, wilted to 51% dry matter, finely chopped and ensiled using 2.2 1 t^-1 (0.5 gallons per ton) of formic acid. The resulting silage had a dry matter digestibility of 72.9% and was fed ad libitum with 3.8 kg (8.4 lb) concentrates as a supplement. A medium-quality grass silage, of lower digestibility and dry matter content (70.0 and 25.4% respectively), was also fed ad libitum in addition to either 3.8, 5.7 or 7.6 kg (8.4, 12.5 or 16.7 lb) concentrates. The feeding treatments were commenced immediately after calving and were terminated on 9 April giving a mean period of 72 d on the treatments. Over the experimental period the animals on the high-quality silage consumed 15% more silage dry matter and produced 8% more milk that those on the medium-quality silage with the same level of concentrate supplementation. From the results it was estimated that 1.9 kg (4.3 lb) of additional concentrates would be required with the medium-quality silage to give an equivalent milk output to that achieved with the high-quality silage. Milk composition, liveweight change, ration digestibility and nitrogen balance data are also presented.     

The nutritional evaluation of Italian ryegrass cultivars fed as silage to sheep and cattle

Three feeding trials with big bale silage were carried out to determine whether previously established intake differences between artificially dried Italian ryegrass cultivars could be repeated under differing conditions of food preparation and presentation. The silage was prepared in 2 consecutive years from the same field crop and fed to groups of cattle in both years. The second year silage was also fed to sheep indoors. All animals were fed ad libitum and the voluntary intakes recorded for groups of cattle and individual sheep. Chewing activity was also recorded on all groups of sheep.
The chemical composition of the two cultivars as fresh grass was similar in 1984 but there were small differences in 1983 with Tarquin showing slightly higher organic matter digestibility (DOMD) and lower dry matter and water-soluble carbohydrate compared to RvP. The only consistent differences in silage composition between cultivars was a slightly higher level of modified acid detergent (MAD) fibre in RvP compared to Tarquin. Despite these small differences the voluntary intake of cattle fed Tarquin was 19% higher than RvP in the first year and 35% in the second, while sheep showed a similar difference of 40% with the second year silage.
Recording of jaw activity with sheep showed that animals spent 40% more time eating and 27% more time ruminating RvP than Tarquin per unit of food eaten. This suggested that the intake differences, which were independent of digestibility, were related to the physical resistance of the feed to breakdown by chewing. These differences depend on the structural characteristics of the plants and were associated with differences in leaf/stem ratios and MAD-fibre content. These are less likely to be affected by the method of conservation or feed presentation and, although the degree of difference between the cultivars changed with the different procedures, the inherently higher intake of Tarquin persisted.     

An investigation on different harvesting methods on young pods of KKU # 922 maize (Zea mays L.) cultivar for baby corn production

This study aimed to search for the best indicator to be used for the harvest of maize pods for baby corn production. A Randomized Complete Block Design (RCBD) with four replications was used. The treatments are: T1 (Control) Taking sample when silks of female flower had extended from tip of pod up to 3 cm long T2, silks had extended 1 cm long T3, silks had extended 2 cm long T4, blooming of female flower for 2 days T5, blooming of female flowers for 4 days T6, blooming of female flower for 6 days T7, one third blooming of male flower T8, two third blooming of male flower and T9, full bloom of male flower. Five baby corn Characteristics were used i.e., (1) fresh weight of whole ears, (2) fresh weight of ears without husk, (3) commercial standard ears, (4) off standard ears and (5) disordered kernel-rows of ears. A range of scores from 1 to 9 was applied to judge quality and yield in each item of the five baby corn characteristics. A score of 1 = the best whilst further increases in scores indicated the decline in quality of baby corn. The results showed that an indicator for use in harvesting pods of maize for baby corn production was found with T6, i.e. the best time for the harvest of pods is when the female flowers had bloomed for 6 days after the appearance of silks.     

Influence of Different Types of Phyllostachys pubescens (Poales: Poaceae) Leaves on Population Parameters of Pantana phyllostachysae (Lepidoptera: Lymantriidae) and Parasitic Effects of Beauveria bassiana (Moniliales: Moniliaceae)

We found that Pantana phyllostachysae, a dangerous pest of moso bamboo (Phyllostachys pubescens), showed differences in growth and development after feeding on diverse types of moso bamboo leaves. The mortality rate of Pa. phyllostachysae due to Beauveria bassiana, an entomopathogenic fungus, was also affected by the varied larval diet. Larval and pupal developmental duration of Pa. phyllostachysae was longer when feeding on “off-year” bamboo leaves. Pupal weight and adult fertility were higher when feeding on “on-year” bamboo leaves. Mortality due to B. bassiana was significantly lower in larvae fed on on-year bamboo leaves than in larvae fed on off-year bamboo leaves. Larvae fed on new bamboo leaves had a shorter development period and higher survival rate than those fed on off-year bamboo leaves. However, mixed feed (mixture of new, on-year, and off-year bamboo leaves) decreased the egg production of Pa. phyllostachysae. After infection by the second generation of B. bassiana, the survival time of Pa. phyllostachysae fed on mixed feed increased significantly compared with the first generation. We also fed Pa. phyllostachysae different proportion of new bamboo leaves in mixed feed to simulate natural conditions. We found that increasing the proportion of new bamboo leaves in the food promoted pupal development and increased egg production; it also increased the resistance of larvae to the first generation of B. bassiana. The pathogenicity of the second generation of B. bassiana declined in all mixed feed treatments.     

中早熟高淀粉玉米品种百粒重变化规律的研究

针对黑龙江省东部淀粉加工企业常用的4个高淀粉中早熟玉米品种,分析其授粉后第18～63 d时百粒重的积累动态.结果表明:中早熟高淀粉玉米在授粉后第18～63 d的灌浆过程中百粒重变化呈增长趋势,增长速率因品种而不同.海玉8和四早11在第18～23 d增长最快,43 d后增长逐渐缓慢,而龙单13和红玉12分别在28～33 d和33～38 d增长最快,48 d后增长减慢.除四早11百粒重在53 d基本达到峰值,其余品种均在第58 d基本达到峰值.     

Effect of restriction of silage intake and the provision of an alternative forage on the performance of dairy cows

In three experiments the effects of restricting the silage ration of dairy cows and of offering alternative forages as buffer feeds were investigated.
In the first experiment of changeover design with 3-week periods, restricting the intake of low-quality silage to 0.62 of ad libitum had no significant effect on milk yield in spite of the large energy deficit. Offering high-quality hay as a buffer feed increased total DM intake and milk production of cows receiving either restricted or ad libitum silage.
In the second experiment of similar design, restricting the DM intake of high-quality silage to 0·58 of ad libitum significantly reduced milk yield and was associated with a large negative energy balance. Offering straw or ammonia-treated straw with the restricted silage diet did not restore milk production to the level achieved with ad libitum silage but these supplements slightly reduced the energy deficit of the cows. In the third experiment of continuous design lasting 7 weeks, restricting the silage ration to 0.85 of ad libitum had no significant effect on milk production. Offering a strawmix based on straw, barley, molasses and soya with the restricted silage ration restored total DM intake to the ad libitum silage level.
In all three experiments milk protein content was reduced by restricting the silage ration and partially restored by offering alternative forages. There were no significant effects on milk fat content and milk lactose content was only reduced by the severest restriction in Experiment 2. It is concluded that short-term minor restrictions of silage intake can be partly sustained by body fat mobilization but more severe restrictions will result in loss of milk yield. Good-quality hay and a strawmix were of benefit in restoring DM and metabolizable energy intakes, whereas straw and ammonia-treated straw were of little value.     

Protein quality of diets based on tuber,legume, and cereal in weanling rats

Weanling male rats (45–55 g) were studied to evaluate the protein quality of diets based on combinations of yam (YA); dehulled brown bean (DBB), dehulled white bean (DWB); and corn flour (PA) that provided 1.6 g N/100 g of diet. Casein served as the reference protein. Rats fed combinations of PA, DBB, and DWB had increases in food intake, weight gain, N intake, digested and retained N, and liver N compared to those of the casein control group and the other test groups (P < 0.05). Supplementation of YA with DBB or DWB reduced weight gain, protein efficiency ratio (PER), N intake, digested and retained N, NPU and liver N values of the animals when compared with those fed the casein and the other diets containing YA. Combinations of DBB or DWB with PA appear to be the best mixtures as shown by food and N intakes, digested and retained N, liver N, and weight gain. These mixtures may possibly be economic sources of N for weaning children where these are staples in the diet.     

Effects of harvest date of timothy (Phleum pratense) on its nutritive value, and on the voluntary silage intake and liveweight gain of lambs

The effects of harvest date of timothy on the chemical composition of herbage and silage, and on the voluntary intake, liveweight gain and feed conversion efficiency by finishing lambs, were evaluated. The herbage was harvested and ensiled on three dates: 16 June (before heading), 20 June and 26 June. The silages were analysed for chemical composition and degradation characteristics by an in vitro gas production (GP) technique with end-point measurements (72 h) of degradability of organic matter (OM) and neutral-detergent fibre (NDF). There were clear effects of later dates of harvest increasing the concentration of NDF, and reducing the degradability of OM and NDF, and the rate of GP, of silages made from this herbage. The silages were fed ad libitum to lambs in a feeding experiment using a Latin square design. Later harvest dates decreased the voluntary intake of silage, liveweight gain and feed conversion efficiency. Lambs fed the early-cut silage had a liveweight gain of 152 g d⁻¹ and those fed the silage harvested 10 d later had a liveweight gain of 76 g d⁻¹. Changes in the chemical composition of herbage and silage and in in vitro degradation characteristics of silages with later harvests were associated, to a large extent, with the reduction in voluntary intake and liveweight gain of lambs.     

微胚乳超高油玉米和高油115玉米的油脂积累规律研究

研究了油脂含量在微胚乳超高油玉米和高油115玉米的胚、非胚部位以及整粒玉米中的变化规律。结果表明：两种玉米胚中油脂含量的变化趋势比较一致,微胚乳超高油玉米单粒胚油重稍低于高油115;微胚乳超高油玉米非胚部位及整粒玉米的油分百分含量明显高于高油115;微胚乳玉米的非胚油重在授粉后21～28 d之后有明显的消减,最终降到其峰值的77.25%～87.71%;微胚乳超高油玉米最终整粒油重稍低于高油115;微胚乳超高油玉米胚油重比低于高油115,表明在微胚乳玉米中有更多的油脂分配在非胚部位。     

Evaluation of propionic acid-treated hay as a feed for growing sheep

Two experiments were carried out to evaluate propionic acid-treated hay as a feed for sheep in which eighteen ewes (experiment 1) and eighteen ewe lambs (experiment 2) were fed ad libitum on hay only. At feeding, the propionic acid-treated hays had higher D-values and water-soluble carbohydrate concentrations, but a lower dry matter concentration, than the untreated hays. The voluntary feed intake and liveweight gain of the sheep fed on two acid-treated hays and on an untreated hay in experiment 1 were similar. In the second experiment an acid-treated moist hay was eaten in greater amounts by the sheep and liveweight gains were greater than on the corresponding untreated hay, but were not significantly different from those of sheep fed on field-cured hay.     

The effects of feeding fodder beet to dairy cows offered silage ad libitum

In a 16-week winter feeding experiment, 48 autumn calving cows and heifers were used to compare a control diet, with two diets including fodder beet at a low and a high level. The control diet was ad libitum silage and 6 kg d^-1 of concentrates (13.4 MJ (kg DM)^-1 of ME and 197 g (kg DM)^-1 of CP). The cows offered fodder beet were fed the control diet (C) plus fodder beet at either 2 (L) or 4 (H) kg DM d^-1. Soya bean meal was offered with the fodder beet at 0.5 or 1.0 kg d^-1 for diets L and H, respectively.
Total dry matter and metabolizable energy intakes were 15.2,16.4 and 17.3 kg DM d^-1; 177, 195 and 211 MJ d^-1 for treatments C, L and H, respectively. The mean milk yields were not significantly affected by the feeding of fodder beet. There was a significant improvement in the fat and protein content of the milk and yield of constituents. The milk composition and yield of solids were: fat content 42.3,44.2 and 45.9 (s.e.d. 1.25) g kg^-1; protein content 33.0, 34.5, 35.3 (s.e.d. 0.76) g kg^-1; fat yield 964,1027,1095(s.e.d. 63.2); protein yield 757, 801, 841 (s.e.d. 48.8) for treatments C, L and H, respectively. The treatments had no significant effect on live weight or condition score change.