叶酸对哺乳仔猪生长性能及母猪血清生化指标的影响

选用带仔数至少为10头的健康长大二元母猪30头,随机分为5个处理,整个泌乳期(21 d)分别饲喂叶酸添加量为0、12.5、25、50和100 mg/kg的日粮,观察其对哺乳仔猪生长性能和泌乳母猪血清生化指标的影响.结果表明,叶酸可提高哺乳仔猪的平均个体日增重,并存在一定的量效关系;当叶酸添加量为125和25 mg/kg时可显著降低母猪血清尿素氮含量(P<0.05);叶酸可提高血清总蛋白含量;不同水平叶酸对泌乳母猪的糖代谢无影响;当叶酸添加量为12.5 mg/kg时可抑制胆固醇的吸收,当添加量为50和100 mg/kg时,则对胆固醇的吸收无影响.     

Efficacy of Chromium(III) Supplementation on Growth,Body Composition,Serum Parameters,and Tissue Chromium in Rats

Chromium(III) is often claimed to have a positive effect on body composition, while the responses in researches with supplementation of different chemical form of chromium are various and inconsistent. We have studied the effects of 6 weeks of treatment with three different forms of chromium (300 μg/kg) as chromium chloride, chromium tripicolinate, and chromium nanocomposite (CrNano) on growth, body composition, serum parameters, and tissue chromium in rats. The supplementataion of CrNano significantly increased average daily gain, food efficiency, and lean body mass and decreased fat mass and body fat proportion and serum levels of glucose, urea nitrogen, triglyceride, and insulin. Chromium contents in liver, kidney, and hind leg muscle were increased significantly with the addition of CrNano in diet. The results indicate that chromium nanocomposite has higher efficacy on growth and body composition compared to the traditional chromium agents.     

Effect of Chromium Picolinate Supplementation on Growth Performance and Meat Characteristics of Swine

The purpose of this study was to evaluate the effect of supplemental chromium (Cr) in the form of chromium picolinate (CrPic) on swine growth performance, meat quality, and protein deposition in skeletal muscle. Forty-eight piglets were divided into three groups randomly, fed with three different dietary levels of Cr (common basal feedstuff supplemented with a dose of 1.61 μg/g or 3.22 μg/g CrPic, which corresponded to 0.2 and 0.4 μg/g Cr). Results indicated that during the growing period (1–35 days), pigs fed with the diet supplemented with CrPic showed no improvement in body mass, average daily gain (ADG), feed consumption, or feed conversion rate (FCR) (P?>?0.05). During the finishing period, a supplementary dose of 0.2 μg Cr/g improved daily weight gain significantly (P?<?0.05), while the situation had no significance with 0.4 μg Cr/g (P?>?0.05) supplemented. For the entire growing-finishing period, body mass increased by 3.86%, ADG rose by 6.08%, and the FCR decreased by 3.30%; levels of total muscular pigment and that in the ribeye areas significantly improved (P?<?0.05) when supplementation with 0.2 μg Cr/g (P?<?0.05) was employed. However, there were no significant changes when supplemented with 0.4 μg Cr/g. While there were no changes in yield of carcass, back fat, water holding capacity, or levels of muscular crude protein and fat (P?>?0.05) in treatment, the ratio of fat-lean and RNA/DNA increased significantly supplemented with 0.2 μg Cr/g (P?<?0.05), but there were no significance with 0.4 μg Cr/g supplementation. In addition, the muscular levels of cholesterol had slightly decreased and the content of DNA in skeletal muscle showed no marked changes with 0.2 or 0.4 μg/g Cr supplementation. In conclusion, the present results suggested that dietary Cr supplementation in the dose of 0.2 μg/g could promote the growth performance, carcass characteristics, and protein deposition.     

Effect of Chromium Supplementation on Productive and Reproductive Performances and Some Metabolic Parameters in Late Gestation and Early Lactation of Dairy Cows

The objective of this study was to determine the effect of supplemental chromium as chromium-L-methionine (Cr-Met) on productive and reproductive performances and some metabolic parameters in late gestation and early lactation of dairy cows. Sixty multiparous Holstein dairy cows according to prior lactation, parity, body mass (682?±?33?kg), and expected calving date were divided equally (30 cows/treatment) and were randomly allocated to one of the two groups. One group received basal diet without Cr (control group) and another group received Cr-Met supplement added at manufacturer's recommended level (8?mg of "Cr"/head per day) from 21?days before expected calving date until 21?days of lactation. Supplemental Cr tended to increase milk yield (P?=?0.08) while percentage of lactose and lactose yield increased (P??0.05). Percentage of cyclic cows at 36?days postpartum and estrous behavior before AI was higher in the supplemented group.     

Dietary Chromium Picolinate Supplementation Affects Growth,Whole-Body Composition,and Gene Expression Related to Glucose Metabolism and Lipogenesis in Juvenile Blunt Snout Bream,Megalobrama amblycephala

Biological Trace Element Research - An 11-week feeding trial was carried out to investigate the effects of supplemented chromium picolinate (Cr-Pic) on the growth, whole-body composition, and...     

The Effects of Dietary Chromium(III) Picolinate on Growth Performance, Vital Signs, and Blood Measurements of Pigs During Immune Stress

This experiment used 24 pigs (26.0 kg) to investigate the effects of dietary chromium (Cr) on pigs challenged with lipopolysaccharide (LPS). Following 35 days of diet exposure, the immune stress treatments were: (1) phosphate-buffered saline (PBS) injection and no Cr, (2) LPS injection and no Cr, (3) LPS injection and Cr 1,000 ppb, and (4) LPS injection and Cr 2,000 ppb. At 0 h, PBS or LPS was injected intraperitoneally in each pig. During the first 12 h post-injection, pigs challenged with LPS lost 951 g, while the PBS group gained 170 g (p?<?0.001). Compared with the PBS group, LPS-challenged pigs consumed less feed (p?<?0.01) during the first 24 h. The LPS group had higher rectal temperature at 2 and 4 h and higher respiratory rate at 1.3 and 8.5 h than the PBS group (p?<?0.05). Plasma collected at 3 h had higher cortisol (p?<?0.001) and lower glucose (p?<?0.05) concentrations in the LPS group than the PBS group. However, supplemental Cr did not affect the response variables. Overall, the LPS challenge affects growth performance, vital signs, and plasma variables, but dietary Cr is unable to moderate stress-related effects associated with an LPS challenge.     

Effect of Dietary Supplementation of Organic Chromium on Performance, Carcass Traits, Oxidative Parameters, and Immune Responses in Commercial Broiler Chickens

An experiment was conducted to study effect of supplementing graded concentrations (0, 100, 200, 300, or 400 μg/kg diet) of organic chromium (Cr) on performance, carcass traits, oxidative stress, and immune responses in commercial broiler chickens reared in open-sided poultry house under tropical climatic conditions. Each diet was fed ad libitum to eight replicates consisting of six birds in each pen from 1 to 42 days of age. Body mass gain and feed efficiency at 21 and 42 days of age and relative mass of liver, abdominal fat, and ready to cook yields at 42 days of age were not affected (P > 0.05) by supplementing organic Cr in broiler diet. Body mass loss during pre-slaughter holding period (12 h) reduced and relative breast mass increased nonlinearly (P < 0.01) with concentration of Cr in diet. Lipid peroxidation decreased, while activities of glutathione peroxidase and glutathione reductase in plasma increased nonlinearly with Cr supplementation. The ratio between heterophyl and lymphocyte was not affected (P > 0.05) with Cr supplementation in broiler diet. Relative mass of lymphoid organs (bursa, spleen, and thymus) and antibody production to Newcastle disease vaccination were not affected (P > 0.05) by the treatments employed. The cell-mediated immunity (lymphocyte proliferation ratio) increased nonlinearly with dietary Cr concentration. The results of the present study indicated that supplementation of organic Cr did not influence body mass and feed efficiency. However, supplementation of the Cr reduced pre-slaughter holding losses, increased the relative mass of breast, and increased antioxidant status and lymphocyte proliferation in broilers reared in tropics.     

Effects of Short-term Supplementation of Clinoptilolite in Colostrum and Milk on the Concentration of Some Serum Minerals in Neonatal Dairy Calves

In recent years, the use of both natural and synthetic zeolites in animal nutrition has increased mainly to improve their performance, health, and to protect against mycotoxin intoxication. Thirty calves were used in the present study for the determination of some physiologic effects of clinoptilolite supplementation. The animals were divided equally into three groups (control, test 1, and test 2). The three groups of calves were homogeneous for parity of dams, sex, and month of birth. For group test 1, clinoptilolite in the concentration of 2% of each colostrum meal was added for 48 h, and for group test 2, clinoptilolite in the concentration of 2% was added to each colostrum and milk meal for 14 days. Blood samples were taken from all calves 12 h after birth and at the end of the first, second, third, forth, fifth, and sixth weeks of life. Calcium (Ca), phosphorus (P), magnesium (Mg), iron (Fe), sodium (Na), and potassium (K) were determined in the serum. For statistical analysis of data, a repeated measures approach using analysis of variance (ANOVA) with mixed linear models was used. Clinoptilolite supplementation had significant effect on the concentrations of calcium, phosphorus, sodium, and iron. The concentrations of Fe significantly higher in test group 2 than other trial groups (p < 0.05). Calcium concentrations were significantly higher in serum of clinoptilolite-treated than control calves (p < 0.05). The concentrations of phosphorus were significantly lower in test groups than control group (p < 0.05). Sodium concentrations were significantly higher in clinoptilolite-supplemented groups than control calves (p < 0.05). Potassium and magnesium concentrations were not affected by clinoptilolite supplementation. Clinoptilolite supplementation could promote iron levels in serum and better hemopoiesis and prevent pathologic or physiologic drop of red blood cell (RBC) parameters in supplemented calves during a first few weeks of life. According to higher need and utilization of Ca in growing animals, clinoptilolite supplementation could increase available Ca. Based on the results of the present study and the importance of dietary phosphorus in many physiologic processes, the level of phosphorus in diet of neonatal dairy calves must be considered and adapted when clinoptilolite was supplemented. With an adequate supply of good quality drinking water, cattle can tolerate large quantities of dietary sodium chloride. Thus, it seems that significant increase in serum Na concentration during short-term supplementation of clinoptilolite in neonatal calves could be well tolerated without any adverse effects.     

Effects of Dietary Chromium (III) Picolinate on Growth Performance,Respiratory Rate,Plasma Variables,and Carcass Traits of Pigs Fed High-Fat Diets

We investigated the effects of supplemental chromium (Cr) as Cr (III) picolinate on pigs fed high-fat diets (HFD) in a 56-day experiment. Thirty-two crossbred pigs (9.6 kg) were allotted to four treatments with four blocks and two pigs/pen. Treatments included: (1) low-fat diet (fat < 3.5%; LFD) with no Cr, (2) HFD (fat > 30%) with no Cr, (3) HFD with 1,000 ppb Cr, and (4) HFD with 2,000 ppb Cr. Pigs fed HFD gained weight faster, consumed less, and had lower feed:gain (p < 0.05). Pigs fed HFD had higher respiration rates than pigs fed LFD on d 41 (p < 0.05). Plasma insulin on d 14 linearly decreased with Cr (p = 0.05). Plasma cholesterol concentrations were higher in the pigs fed HFD than those fed LFD, but were largely unaffected by supplemental Cr. Consumption of HFD resulted in greater carcass weight, perirenal fat, and backfat measures (p < 0.01) compared with the LFD group. Cr resulted in linear reductions of hot carcass weight (p = 0.08) and average backfat (p < 0.05). The effects of Cr on carcass fat measures were more pronounced in castrated males than in females. These results indicate that Cr attenuates some effects of a HFD, mainly body fat accretion of pigs, and especially in castrated pigs.     

Performance,Egg Quality Traits,and Serum Metabolite Concentrations of Laying Hens Affected by Dietary Supplemental Chromium Picolinate and Vitamin C Under a Heat-Stress Condition

A 3?×?2 factorial experiment consisting three levels (0, 200, and 400 μg/kg) of chromium (chromium picolinate) and two levels (0 and 250 mg/kg) of vitamin C was employed to evaluate the effects of these dietary supplements on performance, egg quality traits, and serum biochemical parameters of heat-stressed laying hens (Lohmann LSL-Lite) from 66 to 74 weeks of age. Feed intake increased when birds were given either 400 μg/kg chromium or 250 mg/kg vitamin C (P?<?0.05), but the birds that received both chromium and vitamin C consumed feed similar to those that received only chromium. Dietary treatments had no effect on egg production, egg mass, egg volume, feed conversion ratio, and body mass (P?>?0.05). The birds that fed on diet with chromium or vitamin C produced eggs with higher shell mass and thickness compared to the control. Both eggshell mass and thickness decreased when vitamin C and chromium were supplemented simultaneously, and birds given the diet supplemented with 400 μg/kg chromium and 250 mg/kg vitamin C had eggshell mass and thickness similar to those of the control group. The serum concentration of chromium increased due to increasing level of dietary chromium (P?<?0.05). The birds that received diet with chromium and vitamin C had higher serum concentrations of chromium compared to those that received only chromium (P?<?0.05). Similarly, the hens that received chromium and vitamin C had higher serum concentrations of calcium and phosphorus compared to the hens fed with other treatments (P?<?0.05). The birds given with supplemental chromium exhibited lower serum glucose, total cholesterol, and triglycerides concentrations but higher serum albumin and total protein concentrations compared to the other groups (P?<?0.05).     

Lack of Effect of Dietary Chromium Supplementation on Growth Performance and Serum Insulin, Glucose, and Lipoprotein Levels in Broilers Reared Under Heat Stress Condition

This study evaluated the effects of supplemental dietary chromium (Cr) on the performance, carcass traits, and some serum parameters of broilers under a heat stress (23.9 to 37 °C cycling) condition. A total of 150 1-day-old broiler chicks (Cobb 500) according to a completely randomized design were assigned into five treatment groups. Each treatment consisted of three replicates and each replicate contained ten chicks. Treatments were supplemented with 0 (control), 600, and 1,200 μg kg^?1 Cr in the form of Cr chloride (CrCl₃) and Cr L-methionine from 1 to 49 days of age. Blood samples were collected from two birds in each replicate to determine serum parameters at 35 and 49 days of age. The body mass, feed intake, and conversion ratio were not influenced by dietary Cr (P?>?0.05). Dietary supplementation of Cr from either CrCl₃ or Cr L-methionine caused increased serum concentrations of Cr (P?<?0.05), but had no effect on serum insulin and glucose concentrations at both sampling times (P?>?0.05). Serum triglycerides, very low-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol were also not significantly affected (P?>?0.05) by dietary treatments, whereas total cholesterol concentration decreased in chicks fed Cr L-methionine compared to the control (P?<?0.05).     

Effect of Different Selenium Sources on Productive Performance,Serum and Milk Se Concentrations,and Antioxidant Status of Sows

The experiment was conducted to study the effects of different selenium (Se) sources on productive performance, serum and milk Se concentrations, and antioxidant status of sows. A total of 12 sows (Landrace×Yorkshire) with same pregnancy were randomly divided into two groups; each group was replicated six times. These two groups received the same basal gestation and lactation diets containing 0.042 mg Se/kg, supplemented with 0.3 mg Se/kg sodium selenite or selenomethionine (i.e., seneno-dl-methylseleno), respectively. The feeding trial lasted for 60 days, with 32 and 28 days for gestation and lactation period, respectively. Compared with sodium selenite, maternal selenomethionine intake significantly increased (P < 0.05) the weaning litter weight and average weight of piglet. The Se concentration in the serum, colostrum, and milk of sows were significantly higher (p < 0.05) in the selenomethionine-treated group. The antioxidant status was greatly improved in sows of selenomethionine-treated group and was illuminated by the increased total antioxidant capability (T-AOC; P < 0.05) and decreased malondialdehyde (MDA; P < 0.01) level in the serum of sows, increased T-AOC (P < 0.05), glutathione (GSH) peroxidase (P < 0.05), superoxide dismutase (P < 0.05) and GSH (P < 0.05), and MDA (P < 0.05) level in the colostrum and milk of sows. These results suggested that maternal selenomethionine intake improved Se concentration and antioxidant status of sows, thus maintain maternal health and increase productive performance after Se was transferred to its offspring.     

Effects of Dietary Supplementation of Zinc Oxide and Zinc Methionine on Layer Performance,Egg Quality,and Blood Serum Indices

The objective of this study was to evaluate the effectiveness of dietary zinc oxide (ZnO) and zinc methionine (Zn-Met) supplementation on layer performance, quality of egg, some blood constituents, and oxidative status in blood of laying hens. A total of 120 laying hens (Hisex Brown) 22-week-old were indiscriminately allotted into five groups of 24 hens with six replications (four birds/replicate). A complete randomized design experiment was performed including control (basal diet), two levels of ZnO (50 and 100 mg/kg basal diet), and two levels of Zn-Met (50 and 100 mg/kg basal diet) through 22 to 34 weeks of age. Supplementation of 100 mg of Zn-Met significantly (P = 0.001) increased feed intake compared to other treatment groups. The groups supplemented with 50 mg of ZnO and 100 mg of Zn-Met reported the significantly higher egg production rate (P = 0.002) and egg mass (P < 0.001) compared to other treated groups. All traits of egg quality were not statistically (P < 0.05 or 0.01) affected by ZnO or Zn-Met supplementation except shell thickness, Haugh unit score, and yolk to albumin ratio. Dietary supplementation of either ZnO or Zn-Met did not affect the oxidative parameters in serum except the activity of Cu-Zn-SOD. Serum triglyceride, total cholesterol, and LDL cholesterol (low-density lipoprotein) were significantly (P < 0.05) affected by Zn supplementation, while HDL cholesterol (high-density lipoprotein) did not affect. Compared to the control group, supplementation of ZnO or Zn-Met increased serum content of zinc with no differences among supplemental zinc doses. It could be concluded that dietary inorganic (ZnO) and organic (Zn-Met) supplemented up to 50 and 100 mg/kg, respectively, can be used as effective supplements to improve productivity of laying hens, serum zinc level, lipid profile (triglyceride and LDL cholesterol), and activity of Cu-Zn-SOD.     

Effects of Chromium Picolinate on Oxidative Damage in Primary Piglet Hepatocytes

A proven photocatalyst, titanium dioxide in the form of nano-anatase, is capable of undergoing electron transfer reactions under light. In previous studies, we had proven that nano-anatase could absorb ultraviolet light (UV-B) and convert light energy to stable chemistry energy finally via electron transport in spinach chloroplasts.The mechanisms by which nano-anatase promotes antioxidant stress in spinach chloroplasts under UV-B radiation are still not clearly understood. In the present paper, we investigate the effects of nano-anatase on the antioxidant stress in spinach chloroplasts under UV-B radiation. The results showed that nano-anatase treatment could significantly decrease accumulation of superoxide radicals, hydrogen peoxide (H₂O₂), and malonyldialdehyde (MDA) content, and increase activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), guaiacol peroxidase (GPX), and elevate evolution oxygen rate in spinach chloroplasts under UV-B radiation. Together, nano-anatase could decrease the oxidative stress to spinach chloroplast caused by UV-B radiation.     

不同精氨酸添加水平对哺乳仔猪生长性能的影响

为了研究日粮中不同精氨酸(Arg)水平对哺乳仔猪生长性能的影响,试验选用70头7日龄健康哺乳仔猪(长×大),按照所饲日粮精氨酸添加水平的不同(分别为0、0.2%、0.4%、0.6%和0.8%),随机分为5组,每组14头,单栏饲养,试验期为14 天,并分别于7、14和21日龄空腹称重,记录每周采食量;并在采食后1 h颈静脉采血,检测血浆中氨基酸、血浆尿素氮、胰岛素和生长激素浓度.结果表明:7～21日龄段,试验组血浆精氨酸浓度随日粮精氨酸添加水平增大而升高,与对照组相比,0.6%和0.8%精氨酸添加组血浆尿素氮水平分别降低(P<0.05)30%～40%,生长激素和胰岛素的浓度提高(P<0.05)24%～27%,平均日增重分别提高了(P<0.05)42.2%和41.4%;各组采食量在整个试验期内无显著差异.本试验结果表明7～21日龄,仔猪日粮中精氨酸适宜添加水平为0.6%.     

Efficacy of Dietary Chromium (III) Supplementation on Tissue Chromium Deposition in Finishing Pigs

The study was conducted to evaluate the efficacy of different forms of trivalent chromium (Cr) supplementation on tissue chromium deposition in finishing pigs. A total of 96 pigs with an initial average body mass 65.57±1.05 kg were blocked by body mass and randomly assigned to four treatments with three replicates. Pigs were offered one of four diets including a control diet or the control diet supplemented with 200 μg/kg chromium from either chromium chloride (CrCl(3)), chromium picolinate (CrPic) or chromium nanocomposite (CrNano) for 40 days. During the trial, all pigs were given free access to feed and water. After feeding trial, eight pigs from each treatment were slaughtered for samples collection. The results showed that supplemental CrNano increased Cr content in blood, longissimus muscle, heart, liver, kidney, jejunum, and ileum (P<0.05). Supplemental Cr from three sources increased Cr excretion from all feces (P<0.05). Urinary Cr excretion was increased by CrNano or CrPic supplementation significantly. These results suggested that chromium nanocomposite exhibited more effective on tissue Cr deposition in pigs, which indicated higher absorption compared with CrCl(3) and CrPic.     

Effects of Chromium Picolinate on Micronucleus Frequency and Morphology of Lymphocytes in Calves

We report the effects of chromium picolinate (CrPic) on micronucleus frequency, morphology of lymphocytes, and lipid peroxidation in calves. Twenty-four Holstein calves were selected for the study. They were kept in a farm and were fed a commercially available calf diet and alfalfa, ad libitum. The animals were divided into three groups of eight subjects each and were treated as follows: The first group was supplemented with a daily dose of 200 μg Cr as chromium picolinate; a second group received 400 μg Cr per day and a third group that served as control received no supplemental chromium. After 12-week supplementation, blood samples were collected to determine the micronucleus frequency, the apoptotic cell percentage, and the malondialdehyde (MDA) and blood chromium levels. In both supplemented groups, the cells had irregularly shaped and segmented nuclei. Supplementation also increased the percentage of apoptotic cells (p < 0.001) and serum MDA (p < 0.01) and slightly increased the chromium levels. The animals supplemented with 400 μg showed a significant increase of micronucleus frequency (p < 0.01). The results of this study suggest that supplementation with 200 and 400 μg chromium as chromium picolinate may lead to cytotoxicity. The higher level of supplementation may also have genotoxic effects. However, further studies investigating the mechanism of the action of CrPic are required.