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Evaluation of models for assessing Medicago sativa L. hay quality
G.D.J Scholtz, H.J van der Merwe, T.P Tylutki
South African Journal of Animal Science , 2009,
Abstract: A study was conducted to evaluate current proposed models for assessing Medicago sativa L. hay quality, using near infrared reflectance spectroscopy (NIRS) analyses and Cornell Nett Carbohydrate and Protein System (CNCPS) milk production prediction as a criterion of accuracy. Application of the theoretically-based summative total digestible nutrients (TDNlig) model of Weiss et al. (1992), using lignin to determine truly digestible NDF, explained almost all of the variation in milk yield (MY) (r2 = 0.98). However, this model involves high analysis costs to develop and maintain NIRS calibrations and several of its components were poorly predicted by NIRS and therefore, not suited for quality assessment in practice. Current available models (forage quality index (FQI), relative forage quality (RFQ); relative feed value (RFV)) for assessing Medicago sativa L. hay quality revealed lower accuracies (r2 = 0.83, r2 = 0.76, r2 = 0.61, respectively), especially when protein was included in the model (total forage quality index (TFI); r2 < 0.49). The developed empirical equation named lucerne milk value (LMV), including ADF, ash and lignin (Y = b0 – b1ADF – b2ash – b3lignin) (r2 = 0.96), proved to be the most practical, simplistic, economical and accurate quality evaluation model for commercial application.
Sample preparation of Medicago sativa L. hay for chemical analysis
GDJ Scholtz, HJ van der Merwe, TP Tylutki
South African Journal of Animal Science , 2010,
Abstract: The objective of this study was to quantify the effect of the grinding procedure on the moisture and crude protein concentration of a ground Medicago sativa L. hay sample for quality grading. An additional aim was to investigate the accuracy of electronic moisture testers (EMT). Variance of analyses revealed significant differences in moisture concentration between ground (CV = 16.1%) and unground (CV = 27.4%) samples ranging from 14.7 up to 41.1% of the unground sample. The grinding process had a non-significant influence on the CP concentration of the final grounded product. EMT failed to accurately predict moisture concentration around the moisture area of critical concern (16% and higher) where heat and/or mould damage are likely to occur. It was concluded that analytical moisture standards for Medicago sativa L. hay should be based on the original moisture concentration of samples in the unground state to be relevant for quality grading.
The nutritive value of South African Medicago sativa L. hay
GDJ Scholtz, HJ van der Merwe, TP Tylutki
South African Journal of Animal Science , 2010,
Abstract: A study was conducted to evaluate the variation and expand the existing and limiting nutritive value database of Medicago sativa L. hay (168 near-infrared reflectance spectroscopy spectrally selected samples) in South Africa. The highest moisture content recorded (140 g/kg) was safely below the critical moisture level of 160 g/kg for effective storage. Coefficient of variation (CV) ranged from 1.2% for dry matter (DM) up to 66.2% for acid detergent fibre-crude protein (ADF-CP). The average ash content was 130 g/kg (73 to 295 g/kg), indicating soil contamination. Fibre fractions varied as follows: acid detergent fibre (ADF) (213 to 473 g/kg), neutral detergent fibre (NDF) (289 to 659 g/kg), lignin (43 to 163 g/kg), cellulose (163 to 364 g/kg) and hemicellulose (53 to 199 g/kg). The mean IVOMD for both 24 and 48 h (693 and 732 g/kg DM, respectively), was representative (CV = ± 8%) of the Medicago sativa L. hay population. Crude protein (CP) (average = 207 g/kg DM) consists of 76.9% true protein. According to ADF-CP, 6% of the samples were heat damaged. High mean Ca (13.5 g/kg), P (25.3 g/kg) and Fe (874 mg/kg) values were recorded.
The nutritive value of South African Medicago sativa L. hay
G.D.J Scholtz, H.J van der Merwe, T.P Tylutki
South African Journal of Animal Science , 2009,
Abstract: A study was conducted to evaluate the variation and expand the existing and limiting nutritive value database of Medicago sativa L. hay (168 near-infrared reflectance spectroscopy spectrally selected samples) in South Africa. The highest moisture content recorded (140 g/kg) was safely below the critical moisture level of 160 g/kg for effective storage. Coefficient of variation (CV) ranged from 1.2% for dry matter (DM) up to 66.2% for acid detergent fibre-crude protein (ADF-CP). The average ash content was 130 g/kg (73 to 295 g/kg), indicating soil contamination. Fibre fractions varied as follows: acid detergent fibre (ADF) (213 to 473 g/kg), neutral detergent fibre (NDF) (289 to 659 g/kg), lignin (43 to 163 g/kg), cellulose (163 to 364 g/kg) and hemicellulose (53 to 199 g/kg). The mean IVOMD for both 24 and 48 h (693 and 732 g/kg DM, respectively), was representative (CV = ± 8%) of the Medicago sativa L. hay population. Crude protein (CP) (average = 207 g/kg DM) consists of 76.9% true protein. According to ADF-CP, 6% of the samples were heat damaged. High mean Ca (13.5 g/kg), P (25.3 g/kg) and Fe (874 mg/kg) values were recorded.
Prediction of chemical composition of South African Medicago sativa L. hay from a near infrared reflectance spectroscopy spectrally structured sample population
G.D.J Scholtz, H.J van der Merwe, T.P Tylutki
South African Journal of Animal Science , 2009,
Abstract: The near infrared reflectance spectroscopy (NIRS) to predict chemical and digestibility parameters was investigated. Samples (n = 168) representing the spectral characteristics of the South African Medicago sativa L. hay population were chemically analysed for the development of calibration equations. Values for r2 and ratio of prediction to deviation (RPD) used as estimates of calibration accuracy for these parameters were classified as follows: good for dry matter (DM) (r2 = 0.97; RPD = 4.84), crude protein (CP) (r2 = 0.97; RPD = 4.57), acid detergent fibre (ADF) (r2 = 0.95; RPD = 3.97), neutral detergent fibre (NDF) (r2 = 0.95; RPD = 3.99), lignin (r2 = 0.94; RPD = 3.61), ash (r2 = 0.93; RPD = 3.12) and chloride (Cl) (r2 = 0.95; RPD = 3.74); intermediate for NDF-crude protein (NDF-CP) (r2 = 0.91; RPD = 2.96), sugar (r2 = 0.91; RPD = 2.82), in vitro organic matter digestibility at 24 hr (IVOMD24) (r2 = 0.90; RPD = 2.84) and 48 hr (IVOMD48) (r2 = 0.89; RPD = 2.70); and low (RPD <2.31) for soluble protein (SP), ADF-crude protein (ADF-CP), fat, starch, NDF digestibility (NDFD) and the macro minerals (Ca, P, Mg, P, Na and S). The results recorded in the present study indicated that the NIRS technique is acceptable for DM, CP, ADF, NDF, lignin, ash and Cl analysis and for inclusion in quality models.
Effect of Selection for Crown Diameter on Forage Yield and Quality Components in Alfalfa (Medicago sativa L.)
B.R. Bakheit,M.A. Ali,A.A. Helmy
Asian Journal of Crop Science , 2011,
Abstract: The objective of this investigation was to study the effect of two different methods of selection (modified mass and family selection) for crown diameter on forage yield and quality in Ismailia 91 alfalfa variety (Medicago sativa L.). In 2007/2008, two hundred plants (5% intensity of selection) were selected for crown diameter, using the modified mass selection method. Equal seeds from each selected plant were bulked to form each of two selection cycles. Plants selected for C1 were also raised as half-sib families in 2008/2009 and selection was practiced between and within half-sib families for the best 10 families (5% intensity of selection). Seeds of selected half-sib families and both modified mass selection cycles C1 and C2 along with the base population were evaluated for forage yield and quality in 2009/2010 season. The realized gains after the two mass selection were 9.77, 12.68, 14.94, 14.00, 11.34,-14.91 and 12.47% for crown diameter, root length, fresh forage yield, dry forage yield, crude protein, crude fiber and ash (%), respectively over the base population. Gains from family selection as% of base population were 21.24, 16.91, 17.24, 16.00, 16.49,-16.41 and 18.90% for these traits in the same order. All studied traits were positively correlated but the correlation between crude fiber (%) and other traits were negative. However, two half sib-families (No. 1 and 6) were significantly higher than the original population for all studied traits except crude fiber (%). Results suggest that both mass and family selection for crown diameter resulted in great improvement of forage yield and quality. In addition, family selection appeared to be more rewarding than mass selection in improving yield and quality of alfalfa.
Ingestión y digestibilidad aparente de forrajes por la llama (Lama glama): I.- Heno de alfalfa (Medicago sativa) y paja de trigo (Triticum Aestivum) en diferentes proporciones Intake and apparent digestibility of forages in llamas (Lama glama): I. Alfalfa hay (Medicago sativa) and wheat straw (Triticum aestivum) at different proportions  [cached]
A. LOPEZ V,M. S. MORALES S.,R. CABRERA C.,X. URRA C
Archivos de medicina veterinaria , 2000,
Abstract: Dado el interés que están suscitando los camélidos sudamericanos como una alternativa ganadera para ambientes limitantes no altiplánicos, se decidió evaluar nutricionalmente con llamas (Lama glama), dietas que potencialmente pueden ser utilizadas por ellas. En esta primera etapa se evaluó, a través de un estudio de digestibilidad clásico con recolección total, la digestibilidad de tres dietas logradas por combinaciones de un heno de alfalfa (Medicago sativa) con paja de trigo (Triticum aestivum). Las dietas fueron: 1) 100% alfalfa (Dieta 100); 2) 75% alfalfa + 25% paja (Dieta 75/25); 3) Alfalfa y paja en proporciones de 50 y 50% (Dieta 50/50). Se obtuvieron, en todos los casos, los coeficientes de digestibilidad aparente para materia seca, materia orgánica, proteína cruda y para los diversos componentes de las paredes celulares. Los coeficientes de digestibilidad de las dietas 100, 75/25 y 50/50, fueron, respectivamente, 76,7a, 73,5a y 64,8b (p<0,05) para la PC; 42,8, 42,3, 46,5 para FDN; 39,9, 35,6, 40,9 para FDA; 51,1a, 60,4b, 60,7b (P<0,05) para hemicelulosa y, 52,6, 49,5, 55,6% para celulosa. Mientras la digestibilidad de la proteína disminuyó en las dietas de menor calidad, la digestibilidad de los diferentes constituyentes de las paredes celulares permaneció constante o aumentó en la medida en que la calidad de las dietas disminuían. Estos hechos son coherentes con la información mayoritaria de la literatura que indica la gran habilidad de estos animales para utilizar alimentos fibrosos A random block design was used to run a classical total collection digestion trial, in which eight llamas were used to study the utilization of three different diets: 1) 100% alfalfa hay (Diet 100); 2) 75% alfalfa hay plus 25% wheat straw (Diet 75/25) and 3) 50% alfalfa hay plus 50% wheat straw (Diet 50/50). The digestibility coefficients for dry matter, organic matter, crude protein, and for the components of the cell walls were obtained. The digestibility coefficients of the main nutrients for Diets 100, 75/25 and 50/50 were 76.7a, 73.5a, 64.8b % (P<0.05) for crude protein, respectively; 42.8, 42.3, 46.5% for NDF; 39.9, 35.6, 40.9 for ADF; 51.1a, 60.4b, 60.7b (P<0,05) for hemicellulose and 52.6, 49.5, 55.6% for cellulose. While crude protein digestibility decreased when the quality of diets decreased, the digestibility of the different cell wall constituents remained constant or increased. These facts agree with the general information concerning the greater ability of these animals to utilize fibrous feeds
A novel statistical method for assessing SSR variation in autotetraploid alfalfa (Medicago sativa L.)
Liu, Zhi-Peng;Liu, Gong-She;Yang, Qing-Chuan;
Genetics and Molecular Biology , 2007, DOI: 10.1590/S1415-47572007000300015
Abstract: the level of variation of simple sequence repeat (ssr) markers in cultivated alfalfa from american, australian and chinese sources was evaluated using a novel autotetraploid statistical method to calculate the effective number of alleles, the allele frequencies and heterozygosity. we used 19 ssr primers to screen seven polymorphic ssr loci in 320 plants from eight populations. the genetic distance and phylogenetic analysis (dispan) program was used to calculate the inter- and intra-population genetic relationships using the conventional binary absence/presence (0/1) method and our novel autotetraploid method. the autotetraploid method resulted in significantly higher heterozygosity (p < 0.01), average effective number (p < 0.01) and lower standard genetic distance (p < 0.01) than the binary method. our results suggest that our new autotetraploid method is a very useful tool for assessing genetic variation and genetic relationships in all autotetraploid plant species.
Effect of Autumn and Spring Sowing Dates on Hay Yield and Quality of Oat (Avena sativa L.) Genotypes
Nevzat Aydin,Zeki Mut,Hanife Mut,Ilknur Ayan
Journal of Animal and Veterinary Advances , 2012, DOI: 10.3923/javaa.2010.1539.1545
Abstract: The objective of this study was to investigate the effects of sowing on hay yield and quality of oat genotypes. Sixteen oat genotypes were grown over the consecutive four growing seasons in Samsun, North of Turkey. Hay yield and quality were significantly different between genotypes and sowing dates. Hay yield, Crude Protein (CP), Acid Detergent Fibre (ADF), Neutral Detergent Fibre (NDF), Total Digestible Nutrients (TDN), Relative Feed Value (RFV), Ca, K, P and Mg contents of hay were determined. Hay yield of the oat genotypes in the autumn sowing was higher than in the spring sowing while hay quality (CP, ADF, NDF, TDN, RFV and some elements) in the autumn sowing was lower than in the spring sowing. The hay yield of late-maturing and tall genotypes like Yesilkoy-330, Yesilkoy-1779, Faikbey and Seydisehir (12.1, 12.2, 12.4 and 12.9 t ha-1, respectively) were higher compared with the other genotypes in sowed in autumn. But quality of these genotypes in autumn sowing was lower than the other genotypes. In spring sowing, genotypes Samsun and Kupa had the highest hay yield and fairly high quality. Ca, K and P contents of hay were adequate for ruminants in both sowing dates but Mg content was not adequate. This study showed that sowing date had great effect on hay yield and quality potential of oat genotypes.
Effects of dietary inclusion of alfalfa (Medicago sativa L.) leaf meal and Xylam enzyme on laying hens' performance and egg quality
Mutahar A. Al-shami,,Mohamed E. Salih,Talha E. Abbas
Research Opinions in Animal & Veterinary Sciences , 2012,
Abstract: The experiment examined the effect of inclusion of sun-dried alfalfa leaf meal and 0.05 Xylam enzyme (ALM+X) in laying hens' diet on eggs' production and quality. Forty eight White Hisex laying hens aged 20 weeks were offered four iso-caloric and iso-nitrogenous diets (D , D , D and D of 0.0%, 2%, 5% and 7% ALM, 1 2 3 4 respectively) supplemented with Xylam enzyme (0.05%), for 8 weeks. Supplementation of ALM+X to layer hens’ diet showed insignificant differences in feed consumption, feed conversion ratio, hen-day egg production percentage, egg weight, egg albumin height and egg specific gravity when compared to alfalfa free diet. It also improved eggshell thickness, egg yolk index and egg yolk colour and reduced egg yolk cholesterol. It was concluded that, addition of exogenous enzymes to layer hen diet containing alfalfa overcomes adverse effects of alfalfa on performance parameters and egg quality characteristics.
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