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1.
There is interest in growing peanut (Arachis hypogaea L.) for forage, but little is known about the nutritive value and forage quality of modern cultivars. The objective of this study was to compare the chemical composition and in sacco degradation kinetics of three cultivars of peanuts (cv. ‘C99-R’, ‘Georgia-01R’, and ‘York’) at either stage 2 or 8 maturities when fresh and field-cured. Herbage yield was at least 3000 kg DM/ha for all cultivars at both maturities. Crude protein (CP) was greater (P < 0.0001) at R2 stage than at R8 stage; whereas, neutral detergent fiber (aNDF), acid detergent fiber, and Lignin (sa) were greater (P < 0.01) at R8 than R2 maturity stages. Water soluble carbohydrate and acid detergent insoluble nitrogen was not different (P > 0.07) among cultivars, maturity stage, or harvest forms. In vitro true digestibility was greatest (P < 0.02) for C99-R and least for York. Undegradable intake protein concentration was greatest (P < 0.04) in York and least for C99-R. Maturity had a greater effect on the degradation kinetics than harvest form or cultivar. The dry matter (DM) and CP in the soluble wash fraction (A) and insoluble but degradable fraction (B) and the effective ruminal degradability were greater among all cultivars and both harvest forms of the R2 maturity stage than the R8. The undegradable DM, aNDF, and CP in the undegradable fraction were greatest (P < 0.002) for all three cultivars at R8 maturity. The rate of degradation of DM and CP in the B fraction was faster (P < 0.001) at R2 stage than at R8 stage; whereas, rate of aNDF degradation was not different (P > 0.09) among treatments. Lag of DM, aNDF, or CP degradation was not different (P > 0.1) among treatments. The cultivars C99-R and Georgia-01R are recommended for further feeding trials.  相似文献   

2.
This study evaluated the effect of different feeding regimes from 11 weeks of age to first parturition on feed intake, leptin, non-esterified fatty acids (NEFA) and total protein serum levels, as well as productive performance in young rabbit does. In addition, body composition was estimated by bioimpedance analysis. Thirty-six 11-week-old does were randomly distributed in three groups. The AL-C group was fed ad libitum a control diet containing 350 g neutral detergent fibre (aNDFom)/kg, 11.6 MJ digestible energy (DE)/kg and 173 g crude protein (CP)/kg, and the does were inseminated at 16 weeks of age. The R-C group was fed 150 g/d of the same diet until 16 weeks of age, one week before artificial insemination (AI) at 17 weeks of age, and then fed ad libitum. The AL-F group was fed a diet containing 475 g aNDFom/kg, 9.4 MJ DE/kg and 174 g CP/kg ad libitum, and was inseminated at 17 weeks of age. During rearing (11-16 weeks), does in the R-C group had the lowest DE (1.54 MJ/d; P<0.003) and digestible protein (DP, 17.9 g/d; P<0.001) intake, as well as the lowest protein (172 g/kg; P<0.05) and energy (5.9 MJ/kg) body contents, leptin concentration at 16 weeks of age (2.48 ng/ml; P<0.001) and fertility (P<0.02) at first AI. Daily feed intake during pregnancy and lactation, as well as prolificacy and litter weight, were similar among groups. The highest percentage of body fat was observed for all the does when were inseminated for the first time (135 g/kg; P<0.001), consistent with the highest leptin (4.48 ng/ml; P<0.001) and total protein serum levels (6.87 g/dl; P<0.001) at this time. Serum NEFA level around parturition was higher (P<0.05) in groups AL-C and R-C (1.11 and 0.85 mmol/l) than in group AL-F (0.71 mmol/l), suggesting a lower lipid mobilization that tended to improve fertility rate for AL-F does on day 11 post-parturition (P<0.09). In conclusion, feed restriction during the rearing period delays reproductive development in young rabbits. In nulliparous does, ad libitum feeding during rearing with a high-fibre diet allows a similar productive performance to that of feeding with a less fibrous diet. Nevertheless, the use of high fibre diets during rearing does not affect feed intake throughout the first pregnancy and lactation.  相似文献   

3.
The purpose of this study was to evaluate the effects of various N sources in concentrates containing high levels of cassava chips, with rice straw as the basal forage, on rumen ecology, rumen microbial counts, microbial crude (CP) protein synthesis, and digestibility of nutrients. Four ruminally fistulated crossbred (Brahman × native) beef steers with initial body weight (BW) of 400 ± 40.2 kg were randomly assigned according to a 4 × 4 Latin square design. The dietary treatments were different sources of N in the concentrates and were: T1 = urea (control; urea); T2 = soybean meal (SBM); T3 = urea CaCl2 mixture (U-Cal); T4 = urea CaSO4 mixture (U-Cas). All steers were kept in individual pens and supplemented with concentrate at 5 g/kg of BW daily. The experiment was 4 periods, and each lasted 21 d. During the first 14 d, all steers were fed their respective diets ad libitum and for during the last 7 d, they were moved to metabolism crates for total urine and fecal collection. Dry matter intake ranged from 9.8 to 10.5 kg daily and was not altered by diet, while digestibility of NDF differed among treatments and was highest with U-Cas supplementation (P<0.05). Ruminal NH3 N and plasma urea N with U-Cal, U-Cas, and SBM diets were lower compared with the urea supplemented group (P<0.05). Ruminal volatile fatty acid concentrations were not altered by treatments. Total viable, and cellulolytic bacteria, differed among treatments and were highest with U-Cas (9.1 × 1011, and 4.0 × 109 cfu/mL, respectively). In addition, efficiency of rumen microbial CP synthesis based on organic matter (OM) truly digested in the rumen was increased by SBM or U-Cal supplementation, and was highest with U-Cas supplementation (18.2 g of N/kg of OM truly digested in the rumen). Supplementation of U-Cas to a concentrate containing a high level of cassava chips improved rumen ecology and microbial CP synthesis in beef cattle, suggesting that urea calcium mixtures can replace soybean meal or urea in beef cattle diets without adverse affects on rumen fermentation and other rumen parameters.  相似文献   

4.
This study was conducted to assess effects of harvest date (i.e., 40 and 60 d after planting) and N fertilization rate (i.e., 120, 180, 240 kg N/ha) on the nutritive value of amaranth forage (Amaranthus hypochondriacus) using a factorial experiment with a randomized complete block design. The content of dry matter (DM), crude protein (CP), true protein (TP), ether extract (EE), water soluble carbohydrates (WSC), ash-free neutral detergent fiber (NDFom), ash-free acid detergent fiber (ADFom), lignin(sa), ash, Ca, P, Na, K, oxalic acid and nitrate were determined. Soluble CP (SP) and protein fractions non-protein N (A), true protein rapidly degraded in the rumen (B1), true protein degraded in the rumen at a moderate rate (B2), true protein associated with the cell wall and slowly degraded in the rumen (B3) and acid detergent insoluble CP (C) were measured according to the Cornell Net Carbohydrate and Protein System. In vitro gas production (IVGP), OM disappearance (OMD) and NDFom disappearance (NDFD) were determined using a gas production technique. Results showed that the later harvest date increased (P<0.05) DM, EE, WSC, NDFom, ADFom, lignin(sa), B3 and C; while CP, TP, ash, Ca, P, K, SP, A, B1, B2, nitrate, total and soluble oxalic acid, IVGP, b (i.e., gas production from the insoluble fermentable fractions at 120 h), c (i.e., rate of gas production during incubation), OMD and NDFD decreased (P<0.05). With increasing N fertilization rate, CP, TP, EE, P, nitrate, oxalic acid, SP, A, b, OMD and NDFD increased (P<0.05), however B2 declined (P<0.05). Increasing N fertilization increased yield, CP concentration and nutrient digestibility. At 40 d after planting use of amaranth forage as a ruminant feed is limited due to its high nitrate content. However, at 60 d, although a depression in digestibility and CP content occurred, this forage has the potential as a ruminant feed due to the much lower nitrate levels.  相似文献   

5.
Safflower seed (SS), Carthamus tinctorius L., has the highest concentration of linoleic acid among 80 oilseeds. It was hypothesized that an Iranian variety of SS can be effectively fed with cottonseeds (CS) to maintain feed intake, energy metabolism and productivity of early lactation cows under negative energy balance. Our objective was to determine effects of feeding diets containing 100 g whole CS with (1) no SS (SS0), (2) 75 g CS + 25 g SS (SS25), or (3) 50 g CS + 50 g SS (SS50), per kg of dietary DM, on feed intake, rumen fermentation, blood metabolites and milk production of early lactation cows fed diets based on a uniform mixtures of alfalfa hay and corn silage. Nine multiparous early lactation Holstein cows (46 ± 7 d in milk) were used in a replicated 3 × 3 Latin square design study with three 21-d periods. Each period had 14 d of adaptation and 7 d of data collection. Dietary inclusion of SS did not affect (P>0.10) DM intake, rumen pH and concentrations of ammonia and VFA, blood concentrations of insulin, non-esterified fatty acids, urea and triglycerides, and milk production. Adding SS linearly reduced blood glucose (P=0.05) and beta-hydroxybutyric acid (P<0.05), and increased blood total cholesterol (P<0.01) and low-density lipoproteins (P<0.05) concentrations. Results demonstrated that SS as an economical and rich source of essential fatty acids can be included up to 50 g/kg of dietary DM alongside CS for early lactation cows without affecting feed intake while maintaining rumen fermentation, peripheral energy supply and milk production.  相似文献   

6.
Because starch crystallinity influences the physical, mechanical, and technological aspects of numerous starch-based products during production and storage, rapid techniques for its assessment are vital. Samples of different levels of crystallinity were obtained by debranching gelatinized cassava starch, followed by subjection to various hydrothermal treatments. The recrystallized products were further subjected to partial hydrolysis with a mixture of α-amylase and glucoamylase prior to freeze-drying. Crystallinities were determined using X-ray diffraction (XRD) and 13C CP/MAS NMR spectroscopy, and correlated with FT-Raman spectra features. XRD crystallinities ranged between 0 and 58%, and agreed with crystalline-phase fractions (R2 = 0.99) derived from the respective 13C CP/MAS NMR spectra. A strong linear correlation was found between crystallinities and integrated areas of the skeletal mode Raman band at 480 cm−1 (R2 = 0.99). With appropriate calibration, FT-Raman spectroscopy is a promising tool for rapid determination of starch crystallinity.  相似文献   

7.

Background

Although dietary treatments can successfully reduce blood lipids in hypercholesterolemic subjects, individual variation in that response has on occasion been linked to allelic differences. SNP rs12449157 has shown association with HDL-C concentrations in GWAS and falls in the glucose-fructose oxidoreductase domain containing 2 (GFOD2) locus. Of interest, previous data suggest that this SNP may be under environmentally driven selection. Thus, the aim of this study was to assess if rs12449157 may mediate the response of lipid traits to a dietary supplementation (DS) with soy protein and soluble fiber in a Mexican population with hypercholesterolemia.

Methods

Forty-one subjects with hypercholesterolemia were given a low saturated fat diet (LSFD) for 1 month, followed by a LSFD + DS that included 25 g of soy protein and 15 g of soluble fiber (S/SF) daily for 2 months. Anthropometric, clinical, biochemical and dietary variables were determined. We analyzed the gene–diet interaction between the GFOD2 genotype, with the minor allele frequency of 0.24, and the DS on total cholesterol (TC) and LDL-C concentrations.

Results

Hypercholesterolemic subjects with GFOD2 rs12449157 G allele had higher serum TC and LDL-C at the baseline and showed a greater response to the LSCD + S/SF (− 83.9 and − 57.5 mg/dl, respectively) than those with GFOD2 AA genotype (− 40.1 and − 21.8 mg/dl, respectively) (P = 0.006 for TC, 0.025 for LDL-C, respectively).

Conclusion

The observed differences in allele-driven, diet-induced changes in blood lipids may be the result of a recent environmentally driven selection on the rs12449157 minor allele. Variation in the GFOD2 gene contributes to the genetic basis for a differential response to a cholesterol- or lipid-lowering diet.  相似文献   

8.
9.
Previously starved urchins, Lytechinus variegatus, (36.0 ± 0.8 (SE) mm test diameter) were held in replicated (3) 10-L aquaria with artificial seawater at 22 ± 2  °C and 32‰ salinity and fed three diet treatments. Urchins were fed diets containing 9 : 35, 20 : 23 or 31 : 12% dry protein: % dry carbohydrate (P : C) ad libitum for a 65-day period. Gonads from urchins fed the 9 : 35 P : C diet had similar organic, lower ash, and lower water content than urchins fed the 31 : 12 P : C protein diet. Water content varied with both diet and nutritional history; consequently, water content may have limited value as a predictor of gonad nutritional status. Protein and carbohydrate concentrations in the gonad were directly related to the dietary composition of these nutrients; gonad lipids did not vary with diet. Excess carbohydrates are frequently stored as fats in fish and mammals but this does not appear to be the case in L. variegatus. Test carbohydrate storage and gut protein storage also reflected dietary composition. Image analysis of ovaries indicated decreased nutritive phagocyte volume, increased germinal epithelium volume and larger oocyte diameters in urchins fed high protein, low carbohydrate diets. Analysis of testes also indicated decreased nutritive phagocyte volume and increased gamete volume with urchins fed high protein, low carbohydrate diets, but differences among treatments were less obvious than in ovaries. This study suggests that high protein, low carbohydrate diets promote gamete growth and development. In addition, the biochemical and gametic composition of gonads can be altered by manipulating dietary composition. This could affect the quality and value of sea urchin roe for human consumption.  相似文献   

10.
In light of increasing global protein prices and with the need to reduce environmental impact of contemporary systems of milk production, the current review seeks to assess the feasibility of reducing levels of dietary CP in dairy cow diets. At CP levels between 140 and 220 g/kg DM there is a strong positive relationship between CP concentration and dry matter intake (DMI). However, such effects are modest and reductions in DMI when dietary CP is below 180 g/kg DM can be at least partially offset by improving the digestibility and amino acid profile of the undegradable protein (UDP) component of the diet or by increasing rumen fermentable energy. Level and balance of intestinally absorbable amino acids, in particular methionine and lysine, may become limiting at lower CP concentrations. In general the amino acid composition of microbial protein is superior to that of UDP, so that dietary strategies that aim to promote microbial protein synthesis in the rumen may go some way to correcting for amino acid imbalances in low CP diets. For example, reducing the level of NDF, while increasing the proportion of starch, can lead to improvements in nitrogen (N) utilisation as great as that achieved by reducing dietary CP to below 150 g/kg. A systematic review and meta-analysis of responses to rumen protected forms of methionine and lysine was conducted for early/mid lactation cows fed diets containing ⩽150 g CP/kg DM. This analysis revealed a small but significant (P=0.002) increase in milk protein yield when cows were supplemented with these rumen protected amino acids. Variation in milk and milk protein yield responses between studies was not random but due to differences in diet composition between studies. Cows fed low CP diets can respond to supplemental methionine and lysine so long as DMI is not limiting, metabolisable protein (MP) is not grossly deficient and other amino acids such as histidine and leucine do not become rate limiting. Whereas excess dietary protein can impair reproduction and can contribute to lameness, there is no evidence to indicate that reducing dietary CP levels to around 140 to 150 g CP/kg DM will have any detrimental effect on either cow fertility or health. Contemporary models that estimate MP requirements of dairy cows may require refinement and further validation in order to predict responses with low CP diets.  相似文献   

11.
The traditional Mediterranean diet (MedDiet) has shown beneficial effects on cognitive decline. Nevertheless, diet–gene interactions have been poorly evaluated. We aimed to investigate diet–gene interaction in the PREDIMED-NAVARRA randomized trial. A total of 522 participants (67 ± 6 years at baseline) enrolled in the PREDIMED-NAVARRA trial were randomly allocated to one of three diets: two MedDiets (supplemented with either extra-virgin olive oil or nuts) or a low-fat diet. They were evaluated with the Mini-Mental State Examination (MMSE) and the Clock Drawing Test (CDT) after 6.5 years of intervention. Subjects were genotyped for CR1-rs3818361, CLU-rs11136000, PICALM-rs3851179 and Apolipoprotein E (ApoE) genes. We studied MedDiet–gene interactions for cognition and assessed the effect of the MedDiet on cognition across different genetic profiles. A significant interaction (p = 0.041) between CLU-rs11136000 and the MedDiet intervention on the MMSE was found with a beneficial effect of MedDiet among carriers of the T minor allele (B = 0.97, 95 % CI 0.45–1.49). Similar effect was observed for CR1-rs3818361, but no significant interaction was observed (p = 0.335). For PICALM-rs3851179, the MedDiet intervention showed a beneficial effect in both genotype groups. No apparent interaction was found for the CDT between intervention and gene variants. Similarly, participants randomly allocated to MedDiet groups, with favorable profiles of CR1, CLU and PICALM genes, significantly improved CDT scores compared to controls with the same genetic profile. Cognitive performance was better for non-ApoE4 and for ApoE4 carriers of MedDiet groups compared to controls, but for CDT performance, we only found statistical significant differences for non-ApoE4 carriers. A MedDiet intervention modulates the effect of genetic factors on cognition. The effect of MedDiet might be greater for subjects with a more favorable genetic profile.  相似文献   

12.
Although otolith Strontium (Sr)/calcium (Ca) ratios have been widely used to reconstruct the past salinity environmental history of anguillid eels, factors affecting the Sr/Ca ratios in otoliths are incompletely understood. Japanese Eel (Anguilla japonica) elvers (mean length 54.7 ± 2.1 mm) were collected in the estuary during their upstream migration and reared at 5 different salinities (0, 5, 15, 25, and 35 psu) and 3 types of feeding conditions (formulated feed, tubifex, and starvation) for 30 days to evaluate the effects of salinity and diets on otolith Sr/Ca ratios. Ca and Sr concentrations in the ambient water significantly increased with salinity (SAL) as [Ca] water = 15.50SAL − 5.56, and [Sr] water = 0.21SAL + 0.03, respectively. Sr/Ca ratios in otoliths increased with salinity (SAL) of the rearing water as [(Sr/Ca) × 1000] otolith = 0.091SAL + 3.790. In diets, Sr/Ca ratios were 4 times higher in tubifex than in formulated feed. However, in otoliths, ANOVA indicated that Sr/Ca ratios did not differ significantly between groups fed on tubifex or formulated feed (p = 0.118). Otolith Sr/Ca ratios were negatively correlated with fish growth rates while the growth rates differed significantly among rearing conditions with different salinities and diets. Partition coefficients of the Sr/Ca ratios from ambient water to fish tissues and otoliths significantly increased with salinity. The Sr/Ca ratios of Japanese Eel otoliths thus were positively correlated with the ambient salinity and decreased with increasing fish growth rate, but was not affected by fish diet.  相似文献   

13.
This study aimed to evaluate the protein requirement of Clarias batrachus fry, were estimated at two different water temperatures, 28 and 32 °C. The influence of dietary protein level and water temperature on body composition, weight gain, food and nutrient utilization were estimated. The Asian catfish, C. batrachus fry were fed four diets containing 28% (diet 1), 32% (diet 2), 36% (diet 3) and 40% (diet 4) protein levels and reared at two water temperatures 28 and 32 °C for 60 days. Fry fed with diet 3 containing 36% protein showed the highest mean final body weight at 32 °C. Final body weight was significantly (P<0.05) affected by dietary treatments and temperatures. Clarias batrachus fry raised at 28 °C had higher feed efficiency (93.20%) than the fry reared at 32 °C (87.58%) with 28% dietary protein level. Further, feed efficiency decreased with increase in dietary protein level. Higher daily protein retention (0.089%) observed at lower (0.0217 g) daily protein intake at 28 °C than 0.0283 g at 32 °C. While, optimal (0.0282 g) daily protein intake showed higher daily weight gain at 32 °C. Productive protein value (% PPV) was maximum (1.76%) at 32 °C than at 28 °C (0.76%). Final body lipid recorded higher value than initial body lipid at both the temperatures. Hepatosomatic index (HSI) observed to have been influenced (P<0.05) by diets and temperatures, while viscerosomatic index (VSI) affected (P<0.05) by only diets and not (P>0.05) by temperatures. The study concluded that the diet 3 containing 36% protein was optimal for growth of C. batrachus fry at both the temperatures.  相似文献   

14.
This experiment determined the chemical composition, rumen degradability (aNDF in stalks and starch in kernels) and in vitro gas production of kernels from three corn hybrids treated (TT) or not treated (control, CTR) with insecticides against the European corn borer (ECB, Ostrinia nubilalis). Two whole-plant silage hybrids belonging to the FAO rating 600 and 700 maturity class (S600 and S700, respectively) and one selected for grain production (G600, FAO rating 600, Dekalb-Monsanto Agricoltura S.p.A., Lodi, Italy) were sown in two main plots (TT and CTR) of an experimental field. Two subsequent treatments of pyrethroids (25 and 1.2 g/ha of cyfluthrin and deltamethrin, respectively) were applied to the TT plots. The insecticide treatment reduced the number of damaged plants (4.5 broken plants/plot versus 0.3 broken plants/plot, P<0.01) and increased the total grain yield by 11% (13.8 t/ha versus 12.4 t/ha), while hybrids did not differ. ECB larvae which bored into the stalk tunnels modified the chemical composition of stalks and kernels. In stalks, total sugars content (i.e. glucose, fructose, sucrose) was about twice that in TT versus CTR plants (123 g/kg versus 60 g/kg DM, P<0.01), while aNDF content was higher in CTR stalks (765 versus 702 g/kg DM, P<0.01). DM degradability after 48 h of incubation of stalks was higher in TT than in CTR, both in vitro (0.360 versus 0.298, P<0.01) and in situ (0.370 versus 0.298, P<0.05), while there were no differences in aNDF degradability. Kernels from TT plots contained less DM (615 g/kg versus 651 g/kg, P<0.01) and more CP (84 g/kg and 78 g/kg DM, P<0.05) than those from CTR plots, while in situ rumen starch disappearance and in vitro gas production were similar. Corn hybrid selected for yield of grain (G600) differed from S600 and S700 due to a higher (P<0.01) content of aNDF, ADF and lignin(sa) in the stalks, and a higher starch content (696 g/kg versus 674 and 671 g/kg DM, P<0.01) and CP (87 g/kg versus 77 and 76 g/kg DM, P<0.05) in grain. The G600 hybrid produced stalks with a lower (P<0.01) aNDF rumen degradability than the S600 and S700.  相似文献   

15.
A preliminary experiment was carried out to study the effect of dietary pyridoxine (PN) on thermal tolerance of Labeo rohita fingerlings exposed to endosulfan (1/10th 96 h LC50=0.2 ppb) stress, reared at 26.0±0.5 °C to assess its culture potential in different agro-climatic zones. Two hundred seventy fingerlings were randomly distributed into six treatment groups in triplicate. Five iso-caloric and iso-nitrogenous purified diets were prepared with graded levels of pyridoxine. Six treatment groups were T0 (10 mg PN+without endosulfan), T1 (0 mg PN+endosulfan), T2 (10 mg PN+endosulfan), T3 (50 mg PN+endosulfan), T4 (100 mg PN+endosulfan) and T5 (200 mg PN+endosulfan). After feeding for 60 days, critical temperature maxima (CTmax), lethal temperature maxima (LTmax), critical temperature minima (CTmin) and lethal temperature minima (LTmin) were determined in each group. There was significant (P<0.05) effect of dietary pyridoxine on temperature tolerance (CTmax, LTmax, CTmin and LTmin) of the groups fed diets supplemented with 100 and 200 mg PN/kg diet compared to other experimental groups. Positive correlations were observed between CTmax and LTmax (R2=0.85) as well as between CTmin and LTmin (R2=0.97). The effect was more prominent on lower thermal tolerance limit (CTmin and LTmin). The overall results obtained in this preliminary study indicated that pyridoxine supplementation at 100 mg PN/kg diet enhances the thermal tolerance of endosulfan exposed L. rohita fingerlings.  相似文献   

16.
In the search for new therapeutic tools against tuberculosis two novel iron complexes, [Fe(L-H)3], with 3-aminoquinoxaline-2-carbonitrile N1,N4-dioxide derivatives (L) as ligands, were synthesized, characterized by a combination of techniques, and in vitro evaluated. Results were compared with those previously reported for two analogous iron complexes of other ligands of the same family of quinoxaline derivatives. In addition, the complexes were studied by cyclic voltammetry and EPR spectroscopy. Cyclic voltammograms of the iron compounds showed several cathodic processes which were attributed to the reduction of the metal center (Fe(III)/Fe(II)) and the coordinated ligand. EPR signals were characteristic of magnetically isolated high-spin Fe(III) in a rhombic environment and arise from transitions between mS = ± 1/2 (geff ~ 9) or mS = ± 3/2 (geff ~ 4.3) states. Mössbauer experiments showed hyperfine parameters that are typical of high-spin Fe(III) ions in a not too distorted environment. The novel complexes showed in vitro growth inhibitory activity on Mycobacterium tuberculosis H37Rv (ATCC 27294), together with very low unspecific cytotoxicity on eukaryotic cells (cultured murine cell line J774). Both complexes showed higher inhibitory effects on M. tuberculosis than the “second-line” therapeutic drugs.  相似文献   

17.
It is commonly assumed that because males produce many, tiny sperm, they are cheap to produce. Recent work, however, suggests that sperm production is not cost-free. If sperm are costly to produce, sperm number and/or viability should be influenced by diet, and this has been documented in numerous species. Yet few studies have examined the exact nutrients responsible for mediating these effects. Here, we quantify the effects of protein (P) and carbohydrate (C) intake on sperm number and viability in the cockroach Nauphoeta cinerea, as well as the consequences for male fertility. We found the intake of P and C influenced sperm number, being maximized at a high intake of diets with a P : C ratio of 1 : 2, but not sperm viability. The nutritional landscapes for male fertility and sperm number were closely aligned, suggesting that sperm number is the major determinant of male fertility in N. cinerea. Under dietary choice, males regulate nutrient intake at a P : C ratio of 1 : 4.95, which is midway between the ratios needed to maximize sperm production and pre-copulatory attractiveness in this species. This raises the possibility that males regulate nutrient intake to balance the trade-off between pre- and post-copulatory traits in this species.  相似文献   

18.
The experiment was conducted to determine the protein requirement of Cirrhinus mrigala fry at three different water temperatures, 28, 30 and 32 °C, and to investigate the influence of dietary protein levels and water temperatures on weight gain, body composition, food and nutrient utilization. The 36% protein concentration in the diet yielded highest weight gain at all temperatures from 28 to 32 °C. However, daily protein intake was lower at 28 °C than at 30 and 32 °C. The diet with 36% dietary protein and 32.17% carbohydrate produced the best weight gain and gross conversion efficiency (GCE) at 30 °C. The protein-sparing effect was observed at temperatures 30 and 32 °C in diets 1 and 2, having carbohydrate levels 37.36–44.91%. Highest protein efficiency ratio (PER) was recorded at 28% dietary protein level, while it was lowest at 40% dietary protein level in all three temperatures. Lipid in the body of fishes increased at the end of the experiment in comparison to the initial body lipid. The body protein was found to be related to daily protein intake at 30 and 32 °C. Significant difference (P<0.05) was also noted between temperatures, the hepatosomatic index (HSI) and viscerosomatic index (VSI). The diet with 36% dietary protein and 32.17% carbohydrate was observed to be the best diet for C. mrigala fry at 28–32 °C.  相似文献   

19.
Entomopathogenic nematodes, Heterorhabditis indica and Steinernema riobrave, were tested for virulence and reproductive yield in Tenebrio molitor that were fed wheat bran diets with varying lipid- and protein-based supplements. Lipid supplements were based on 20% canola oil, peanut, pork or salmon, or a low lipid control (5% canola). Protein treatments consisted of basic supplement ingredients plus 0, 10, or 20% egg white; a bran-only control was also included. Some diet supplements had positive effects on nematode quality, whereas others had negative or neutral effects. All supplements with 20% lipids except canola oil caused increased T. molitor susceptibility to H. indica, whereas susceptibility to S. riobrave was not affected. Protein supplements did not affect host susceptibility, and neither lipid nor protein diet supplements affected reproductive capacity of either nematode species. Subsequently, we determined the pest control efficacy of progeny of nematodes that had been reared through T. molitor from different diets against Diaprepes abbreviatus and Otiorhynchus sulcatus. All nematode treatments reduced insect survival relative to the control (water only). Nematodes originating from T. molitor diets with the 0% or 20% protein exhibited lower efficacy versus D. abbreviatus than the intermediate level of protein (10%) or bran-only treatments. Nematodes originating from T. molitor lipid or control diets did not differ in virulence. Our research indicates that nutritional content of an insect host diet can affect host susceptibility to entomopathogenic nematodes and nematode fitness; therefore, host media could conceivably be optimized to increase in vivo nematode production efficiency.  相似文献   

20.
This study measured the effects of replacing corn silage and vetch hay by soy hulls in total mixed rations (TMRs) fed to 25 pairs of cows through 90 d in milk, on dry matter (DM) intake, in vivo digestibility, milk yield and composition, onset of normal estrous activity, body condition score (BCS), health and the energy balance of lactating cows. The partitioning of metabolizable energy (ME) intake between heat production (HP) and retained energy (RE) in milk and body change of each cow was measured. The two TMRs differed in the content of forage and forage aNDFom [235 g/kg versus 350 g/kg; and 128 g/kg versus 187 g/kg DM, in the experimental (EXP) and control (CON) diets, respectively]. This was reflected by an increase in voluntary DM intake by 7.2% (P=0.02) in the EXP group as compared with the CON. In vivo DM and aNDFom digestibility were 4.9% (P=0.03) and 22.7% higher (P=0.01), respectively, in the EXP group than in the CON. The higher DM intake and digestibility of the EXP TMR were reflected by a concomitant increase of 7.4% in milk yield and 10.8% in RE (P=0.01) of the EXP cows as compared with the CON. The two dietary groups expressed similar somatic cell counts, and metabolic disorders (i.e., ketosis and/or lameness), as well as pedometer activity (steps/h) suggesting similar udder health, behavior and animal welfare. A trend to an earlier return to normal ovarian activity occurred in the EXP cows as reflected by fewer days to 1st ovulation and advanced outset of estrous cycle. Despite the higher RE of the EXP cows, the HP of both groups was maintained at an upper level of 141–136 MJ/cow/d during the 90 d of the experiment.  相似文献   

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