Silage

Inoculation of maize silage with Lactobacillus buchneri (5 x 10(5) c.f.u. g(-1) of maize silage) prior to ensiling results in the formation of aerobically stable silage. After 9 months, lactic acid bacterium counts are approximately 10(10) c.f.u. g(-1) in these treated silages. An important subpopulation (5.9 x 10(7) c.f.u. g(-1)) is able to degrade 1,2-propanediol, a fermentation product of L. buchneri, under anoxic conditions to 1-propanol and propionic acid. From this group of 1,2-propanediol-fermenting, facultatively anaerobic, heterofermentative lactobacilli, two rod-shaped isolates were purified and characterized. Comparative 16S rDNA sequence analysis revealed that the newly isolated bacteria have identical 16S rDNA sequences and belong phylogenetically to the L. buchneri group. DNA-DNA hybridizations, whole-cell protein fingerprinting and examination of phenotypic properties indicated that these two isolates represent a novel species, for which the name Lactobacillus diolivo...

In the humid and sub-humid areas, agricultural production is largely rain fed and this needs to be urgently supplemented by irrigation practice if the country is to meet its food demand. A two years study was carried out at the experimental site of the Institute of Agricultural Technology and Biosystems Engineering, Johan Heinrich von Thünen Institute (vTI), Braunschweig, Germany to compare performance of maize crop for silage production using three different irrigation systems; rain fed, drip and rain-gun sprinkler. Growth parameters such as plant height, stem diameter were measured. The total yields of silage were obtained for all treatments at the harvesting. The experimental results reveal that total yields obtained from different treatments were 25.76, 24.23 and 9.30 Mg ha -1 in drip, rain-gun and rain fed irrigated maize, respectively. The results also showed that the water use efficiency reached 11.01 kg m -3 for drip irrigation in while it was 8.84 kg m -3 for rain-gun syste...

MSc. Thesis by Saja I. Abid, supervised by Prof. Dr. Ali A. Saeed
Abstract
This study was conducted to investigate the possibility of improving nutritive value of rice straw by ensiling and to make use of desired taste of good quality silage. In addition to possibility of improving chemical composition by addition of urea and ruminant manure. Samples of rice straw silage were prepared in nutrition laboratory of Animal Production Department-College of Agriculture- Alqasim Green University. Straw was chopped manually to 1-2 cm and treated with treatment solution.  This solution was prepared by addition of 10% of low quality date honey as a source of soluble carbohydrates and commercial urea as a source of non-protein nitrogen at rate of 2%. Manure was used to substitute different ratios of urea on basis of nitrogen content. Accordingly 6 combinations were formed of urea: manure, 100:0, 90:10, 80:20, 70:30, 60:40 and 50:50. Treatment solution was diluted with estimated quantity of water to adjust dry matter content to about 40%. Silage components were packed in double plastic bags which were well compressed to exclude air and were tightly closed and stored underground for 60 days.
Results revealed that samples of rice straw silage prepared by addition of sheep manure were characterized with lower (P˂0.01) dry matter loss as compared with other samples. Samples prepared with cow manure recorded higher (P˂0.01) crude protein content as compared with those treated with sheep and buffalo manure, 3.59, 3.44 and 3.26% respectively. Increase protein content was noticed in all samples prepared with addition of manure as compared with samples prepared with addition of urea only (combination 100:0). Regarding cell wall components, samples prepared by addition of sheep manure recorded (P˂0.01) lower content of acid detergent fiber (39.98%), and higher (P˂0.01) content of hemicellulose as compared with samples prepared by addition of cow and buffalo manure, 74.45, 74.31 and 72.50% respectively. Reduction (P˂0.01) in content of acid detergent fiber and cellulose was recorded with combinations of 50:50, 60:40 and 70:30 in comparison with other combinations. Increase (P˂0.01) in hemicellulose and lignin was recorded with increasing level of manure in studied combination. Results of current study revealed different trend in neutral detergent fiber, lower values (P˂0.05) were associated with samples prepared with combination of 70:30 of urea: manure.
Regarding parameters of silage fermentation, results showed improvement due to addition of sheep manure as evidenced by reduction in pH values and concentration of ammonia nitrogen (5.04 and 0.642) as compared with values of samples prepared by addition of cow manure (5.17 and 0.679) and buffalo (5.31 and 0.682 g/100 g total nitrogen).  Samples prepared with addition of cow manure were characterized with higher (P˂0.01) concentration of total vaporized fatty acids. Reduction (P˂0.01) in pH was noticed with increasing level of manure as compared with combination of 100:0 which recorded higher (P˂0.01) value (6.16) and higher (P˂0.01) concentration of ammonia nitrogen as well. Samples prepared with combinations of 70:30, 60:40 and 50:50 were characterized with higher (P˂0.01) concentration of total vaporized fatty acids, 1.994, 2.126 and 2.018 % of dry matter respectively.
In microbial evaluation, samples prepared by addition of buffalo manure were characterized with lower (P˂0.01) number of yeasts, molds, aerobic bacteria, 4.46, 3.62 and 5.84, beside higher (P˂0.01) number of lactic acid bacteria. Lower number of these microbes and anaerobic bacteria were recorded in samples prepared with combination of 100:0 of urea: manure.                     
Concerning quality parameters, samples prepared by addition of sheep and cow manure recorded higher (P˂0.01) Fleig points as compared with those prepared by addition of buffalo manure, 60/42, 55.58 and 49.59 respectively.  Reduction (P˂0.01) in this parameter was noticed in samples prepared with combination of 100:0. Regarding aerobic stability, results revealed that there was a reduction (P˂0.01) in samples prepared by addition of sheep manure by 15 and 13 hours in comparison with samples prepared by addition of cow and buffalo manure respectively. Samples prepared with combination of 100:0 were prior (P˂0.01) as compared with other samples. Results also showed increase (P˂0.01) in in vitro digestibility of organic matter in samples prepared by addition of sheep manure in comparison with samples prepared by addition of cow and buffalo manure, 49.99, 44.59 and 42.77% respectively. Samples prepared with combination of 100:0 recorded lower (P˂0.05) decrease in in vitro digestibility of dry matter as compared with combinations of 70:30 and 60:40 of urea: manure, 40.52, 45.36 and 45.94% respectively. All silage samples recorded different improvement in in vitro digestibility of organic matter as compared with straw pre-ensiling. However, better values (P˂0.01) were achieved in combinations of 50:50 and 60:40 (46.82 and 46.78% respectively).

El maíz, cultivo ampliamente utilizado en Argentina, se utiliza por su producción de grano y también como forraje. Los aportes del mejoramiento genético y la adopción de herramientas de manejo como la fertilización contribuyen con la mejora de los rendimientos de maíz. En la asignatura Genética de la FAV de la UN de Río Cuarto se han obtenido genotipos de maíz híbrido, doble y de tres líneas, con aptitud doble propósito: producción de forraje y de grano.
Los objetivos del presente trabajo fueron: i) caracterizar híbridos dobles y seleccionar híbridos dobles y de tres líneas por el comportamiento para doble propósito y ii) evaluar los híbridos selectos bajo diferentes dosis de fertilización nitrogenada. Diferentes caracteres productivos se evaluaron en dos ensayos consecutivos. En el primer año de ensayo se
evidenciaron diferencias estadísticamente significativas en quince caracteres medidos, lo que permitió seleccionar diez materiales por su aptitud doble propósito. En el segundo año de ensayo se evaluaron los híbridos selectos con diferentes dosis de fertilización nitrogenada.
Las diferentes dosis de nitrógeno no evidenciaron diferencias estadísticamente significativas, ni tampoco se manifestó interacción entre los niveles de fertilización y los híbridos evaluados. En nueve caracteres medidos los genotipos manifiestan diferencias estadísticamente significativas entre los genotipos, lo que permitió identificar aquellos con aptitud forrajera o granífera. Uno de los híbridos evaluados se destacó por su aptitud doble propósito.

MSc. Thesis by Haitham M. H. Al-Sultany, supervised by Prof. Dr. Ali A. Saeed
Abstract
    This study was conducted to investigate the possibility of improving palatability and nutritive value of reed by ensiling due to desired taste that good quality silage characterized with and improving digestion and chemical composition by addition of urea. Silages were prepared in Animal field of Animal Resources Department-College of Agriculture/Al-Qasim Green University. Where reed was treated with solution containing debis at rate of 10% as source of soluble carbohydrates and urea as a source of nitrogen at 3 rates, 0, 1 and 2%. 24 Awassi male lambs were used with 4-6 months of age and mean initial weight of 20.59 kg. Lambs were randomly distributed into 6 groups in individual pens with 4 lambs per each.
Roughages (silage and reed) were offered ad libitum, whereas, concentrate was offered at rate of 2% of body weight. This study was lasted for 10 weeks following preliminary period for 19 days.
Results revealed that dry matter (DM) and crude fiber contents were reduced and crude protein (CP), ether extract and metabolizable energy (ME) contents were increased due to ensiling. Whereas, urea treatment increased CP and ME contents. Reed was characterized with higher increase in CP as compared with silage; this increase was 3.1 and 2.74 for reed vs. 1.76 and 2.74% for silage at urea levels of 1 and 2% respectively.
Regarding silage fermentation, it was observed that pH, ammonia nitrogen (NH3-N) and total volatile fatty acids (TVFA) assumed similar trend to increase with increasing level of urea treatment, urea untreated reed silage and that treated with urea at rate of 1% recorded low pH (3.7 and 4.3, respectively) as compared with high pH value for reed silage treated with high level of urea (6.7). These values were reflected on quality parameters, where, higher Fleig points were estimated for the former two silages (132.98 and 115.46, respectively). Lower DM loss was estimated in reed silage treated with lower level of urea as compared with untreated and that treated with high level of urea, these loss ratios were 14.05, 17.73 and 22.80 respectively. Concerning aerobic stability, better values were related with level of urea. Values were 39.5, 38.5 and 31.5 hours for reed silages treated with 2, 1 and 0% respectively. Regarding buffering capacity, results showed lower values with increasing urea treatment, where, released ammonia from degradation of urea during ensiling neutralized organic acids accumulated in stored mass.
Results also revealed that lambs fed reed were significantly superior in intake of all nutrients with exception of digestible DM intake and organic matter (OM) intake, where, values did not differed significantly due to improvement in digestion caused by ensiling. Intake of OM of roughages, total nitrogen (N), total digestible N, total rumen degradable N (RDN) and RDN:ME were affected (P˂0.01) by urea treatment. Moreover, intake of all nutrients except that of total digestible OM was significantly affected by interaction between ensiling and urea treatment.
Ensiling improved digestibility coefficients of all nutrients except that of nitrogen free extract and hemicellulose, whereas, it decreased (P<0.05) CP digestibility (67.03 and 69.59% for silage and reed, respectively. Digestibility was also affected by urea treatment, where, better values were generally achieved with 1% of urea except those of fiber components, in which, 2% level of urea was superior in acid detergent digestibility (P<0.05) and hemicellulose (P<0.01), and mathematically in NDF and cellulose digestibilities.
Final weight and average total and daily gain were not affected by ensiling and level of urea, corresponding values were, 25.93, 5.52 and 78.86 for lambs fed reed silage vs. 27.18 kg, 6.07 kg and 86.83 g/day for reed respectively. Final gain was not affected by interaction between ensiling and level of urea, whereas, lambs fed reed treated with low level of urea gained higher average final and daily gain. Ensiling was significantly superior in feed conversion ratio (FCR) estimated on basis of DM intake (7.74 vs, 8.86) and digestible protein (0.09 vs. 0.11). Whereas, 0% level of urea showed significant superiority in FCR regardless to basis of estimation. Lambs fed untreated reed silage recorded better FCR in comparison with other lambs.
Regarding ruminal fermentation, results pointed out that pH was increased (P<0.01) due to ensiling, values were 6.91 vs. 6.71 for silage and reed respectively, yet it was no affected by level of urea. Higher (P<0.01) value of ruminal NH3-N was detected in samples withdrawn from lambs fed read treated with high level of urea as compared with untreated silage (10.21 vs. 11.05 mg/100 ml for silage and reed respectively). Ruminal TVFA was not affected by ensiling (5.67 vs. 5.65 mmol/100 ml) and level of urea treatment. Untreated silage and reed treated with 2% of urea recorded higher pH and NH3-N respectively. Higher pH and TVFA were recorded in samples withdrawn before feeding to be decreased at 3 hours post feeding, than it increased after 6 hrs. Higher level of NH3-N in samples withdrawn 3 hours post feeding, then it decreased at 6 hours post feeding, however, it was still higher than those recorded at before feeding.
Results of study showed that there was a significant effect (P<0.01) for treatment  with high level of urea on concentration of blood urea nitrogen (BUN), values were, 41.67, 40.88 and 48.39 ml/100 ml for 0, 1 and 2% levels of urea respectively. No significant effect was observed for ensiling and urea treatment on other blood parameters. However, a significant effect (P<0.05) was noticed for interaction between ensiling and urea treatment on concentration of total protein (TP) and NH3-N. Higher (P<0.01) blood glucose concentration was detected in samples withdrawn before feeding (79.86) as compared with those in samples withdrawn at 3 and 6 post feeding (71.92 and 69.61 mg/100 ml respectively), whereas, Higher concentrations of TP and NH3-N were detected in samples withdrawn 3 hours post feeding, values were 10.54 g/100 ml and 51.98 mg/100 ml respectively. Higher total triglycerides concentration was detected in samples withdrawn at 6 hours post feeding.

The objective of this study was to determine the feeding value of forage soybean silage (SS) for dairy cows relative to a fourth-cut alfalfa silage (AS). Forage soybean was harvested at full pod stage. Two isonitrogenous diets were formulated with a 48:52 forage:concentrate ratio. Soybean silage and AS constituted 72% of the forage in each diet, with corn silage constituting the remaining 28%. Twenty Holsteins cows in early lactation were used in a switchback design. Four lactating Holsteins cows fitted with ruminal cannulas were used to determine the effects of dietary treatments on ruminal fermentation parameters and in vivo total tract nutrient utilization. Relative to AS, SS contained 15, 28, and 25% more neutral detergent fiber, acid detergent fiber, and crude protein, respectively. Dry matter intake (23.5 vs. 25.1 kg/d) and milk yield (35.5 vs. 37.2 kg/d) were lower for cows fed SS than for those fed AS. However, energy-corrected milk and milk efficiency were similar for both ...

A meta-analysis based on published experiments with lactating dairy cows was conducted to study the effects of dietary forage and concentrate factors on apparent total diet digestibility. A data set was collected that included a total of 497 dietary treatment means from 92 studies. The diets were based on grass silage or on legume or whole-crop cereal silages partly or completely substituted for grass silage. The silages were supplemented with concentrates given at a flat rate within a dietary comparison. For the statistical evaluation, the data were divided into 5 subsets to quantify silage (digestibility, 42 diets in 17 studies; fermentation characteristics, 108 diets in 39 studies) and concentrate (amount of supplementation, 142 diets in 59 studies; concentration of crude protein, 215 diets in 82 studies; carbohydrate composition, 66 diets in 23 studies) factors on total diet digestibility. The diet digestibility of dairy cows was determined by total fecal collection or by using ...

This study investigated the effects of plant species (red clover vs. timothy-meadow fescue) and forage maturity at primary harvest (early vs. late cut silage) on rumen fermentation, nutrient digestion, and nitrogen metabolism including omasal canal AA flow and plasma AA concentration in lactating cows. Five dairy cows equipped with rumen cannulas were used in a study designed as a 5 x 5 Latin square with 21-d periods. The diets consisted of early-cut and late-cut grass and red clover silage, respectively, and a mixture of late-cut grass and early-cut red clover silages given ad libitum with 9 kg/d of a standard concentrate. Grass silage dry matter intake tended to decrease but that of red clover silages tended to increase with advancing maturity. Milk yields were unchanged among treatments, milk protein and fat concentrations being lower for red clover than for grass silage diets. Rumen fluid pH was unchanged but volatile fatty acid and ammonia concentrations were higher for red clo...

This experiment was conducted to determine the effects of corn silage hybrids and nonforage fiber sources (NFFS) in high forage diets formulated with high dietary proportions of alfalfa hay (AH) and corn silage (CS) on ruminal fermentation and productive performance by early lactating dairy cows. Eight multiparous Holstein cows (4 ruminally fistulated) averaging 36±6.2 d in milk were used in a duplicated 4 × 4 Latin square design experiment with a 2 × 2 factorial arrangement of treatments. Cows were fed 1 of 4 dietary treatments during each of the four 21-d replicates. Treatments were (1) conventional CS (CCS)-based diet without NFFS, (2) CCS-based diet with NFFS, (3) brown midrib CS (BMRCS)-based diet without NFFS, and (4) BMRCS-based diet with NFFS. Diets were isonitrogenous and isocaloric. Sources of NFFS consisted of ground soyhulls and pelleted beet pulp to replace a portion of AH and CS in the diets. In vitro 30-h neutral detergent fiber (NDF) degradability was greater for BMR...

This study was conducted in Nutrition laboratory to investigate the effect of addition of different levels of Ecosyl, a commercial inoculant of lactic acid bacteria (LAB), 0, 1×105 or 1×106 cfu/g fresh matter (FM) and four levels of debis (date honey) as a source of soluble sugars (WSC), 4, 6, 8 or 10% on dry matter (DM) basis on sensory characteristics and chemical composition of wheat straw silages (WSS). Silage samples of 400-500 g were made with 4 replicates after chopping wheat into 1-1.5 cm. Urea was added at rate of 1% to all samples to increase nitrogen (N) content of straw in all silages. Treated samples were packed in nylon bags and ensiled for 60 days. Results revealed that color of WSS samples were ranged between light and dark yellow to greenish yellow. Most inoculated samples were characterized with accepted odor. Results also showed significant (P<0.01) reduction in fibrous components, particularly, neutral detergent fiber from 43.73 to 39.40 and 37.79%, and cellulose from 29.32 to 24.60 and 22.05% were observed in samples of WSS prepared without and with addition of LAB inoculant at level of 1×105 and 1×106 cfu/g FM respectively. This reduction was correlated with significant (P<0.01) increase in hemicellulose and crude protein (CP) contents. Silages prepared with WSC at level of 10% had lower (P<0.01) contents of acid detergent fiber and cellulose, 37.48 and 23.33% respectively. However, increasing level of debis decreased contents of CP (P<0.01) and ether extract (P<0.05).

In this study, changes in the chemical composition, pH, cell wall and degradability of ensiled rice straw were investigated when treated with alkali, acid, oxidant agents (1–11 %, w/w) and a combination of an oxidant with either an alkali (ALHP) or an acid (ACHP). The findings of the study revealed that ALHP had a lower efficiency in enhancing fibre degradability compared to alkali alone. Oxidant treatment showed no detectable changes in pH, dry matter (DM) and phenolic compound (PC) solubility, or in silica and fibre content, but led to increased esterified groups formed within the cell wall constituents (hemicellulose and lignin). Increasing acid concentration led to an exponential change in both pH and solubility of DM and hemicelluloses while it quadratically increased PC and silica solubility. Moreover, crystallinity, hydrogen bonding and esterification were enhanced under high acid concentrations (11 %), but decreased under mild acid conditions (5 %). Increased alkalinity led to the linear enhancement of DM and PC solubility. Solubility of silica and hemicellulose did not exhibit any significant changes with alkali concentration above 7 %. A gradual enhancement (29 %) was observed in ruminal DM degradability with increasing oxidant concentration, whereas exponential (91 %) and quadratic (23 %) enhancements were observed with alkaline and acid treatments, respectively. Treatment with acid showed observable reductions in the degradability of both cellulose and hemicellulose, whereas oxidant treatment reduced only that of hemicellulose. Treatment with 7 % alkali (pH ∼ 12) followed by ensiling appeared to be a promising process for improving rice straw quality.

Effects of legume maturity on dry matter intake (DMI), milk production, ruminal fermentation and pool sizes, and digestion and passage kinetics, and the relationship of these effects with preliminary DMI (pDMI) were evaluated using 16 ruminally and duodenally cannulated Holstein cows in a crossover design with a 14-d preliminary period and two 17-d treatment periods. During the preliminary period, the pDMI of individual cows ranged from 22.9 to 30.0 kg/d (mean=25.9 kg/d) and the 3.5% fat-corrected milk yield ranged from 34.1 to 68.2 kg/d (mean=43.7 kg/d). Experimental treatments were diets containing alfalfa silage harvested either a) early-cut, less mature (EC) or b) late-cut, more mature (LC) as the sole forage. Early- and late-cut alfalfa contained 40.8 and 53.1% neutral detergent fiber (NDF) and 23.7 and 18.1% crude protein, respectively. Forage:concentrate ratios were 53:47 and 42:58 for EC and LC, respectively; both diets contained approximately 22% forage NDF and 27% total ND...

To increase the production of milk from forage (MF), a previous experiment with alfalfa silage showed the importance of a complementary combination of concentrates and forages offered. When corn silage is fed with alfalfa, increasing the rumen degradable protein (RDP) content in the diet should allow a better utilization of forage energy. To evaluate this hypothesis, 8 multiparous Holstein cows in early lactation were used in a replicated 4 x 4 Latin square design with 3-wk periods. Diets were fed as total mixed rations and were formulated to provide similar levels of net energy for lactation and crude protein but differing in RDP. Corn and alfalfa silages were used. Treatments were: 1) cracked corn-based concentrate providing low RDP [level recommended by the NRC (2001); RDP = 11.1% of dry matter (DM)]; 2) cracked corn-based concentrate providing medium RDP (RDP = 12.8% of DM); 3) cracked corn-based concentrate providing high RDP (RDP = 14.5% of DM); and 4) ground corn-based concen...

Milk from forage (MF) is an estimation of the milk produced solely from forage intake. It is calculated by subtracting milk production theoretically allowed by concentrates from total milk production, assuming that maintenance requirements are covered by the forage portion of the diet. Eight multiparous Holstein cows in early lactation were used in a replicated 4 x 4 Latin square design to evaluate the impact on MF of different sources of carbohydrate with forage that was high in RDP. Diets were alfalfa-based total mixed rations that were formulated to provide similar concentrations of NEL and CP while differing in rumen degradability of concentrate carbohydrates. Treatments were 1) cracked corn (control), 2) ground corn (GC), 3) GC plus wheat starch (GC+S), and 4) GC plus dried whey permeate (GC+W). The GC and the GC+S treatments increased MF as calculated on a protein basis (14.8 vs. 10.5 kg) and increased average MF production (8.6 vs. 5.5 kg) compared with the control. Protein o...

We conducted three experiments to determine the influence of mechanical processing on corn silage utilization by lactating dairy cows. Total mixed rations contained either unprocessed or processed corn silage harvested between 1/4 and 3/4 milk line. In trial 1, 12 multiparous Holstein cows were used in a replicated double switchback design with 21-d periods. Intake of dry matter (DM) was increased 1.2 kg/d by processing, but milk yield was unaffected. Processing did not affect apparent total-tract DM digestibility, but processing tended to lower starch and corn excretion in feces and reduced concentration of sieved corn kernel particles in feces. In trial 2, 42 Holstein cows were used in an 18-wk randomized complete-block design. Intake of DM and milk yield were unaffected by processing, but milk fat percent was increased 0.35 percentage units by processing. Processing tended to increase total-tract digestibility of starch, but reduced organic matter, crude protein, and neutral dete...

This study conducted according to a 4 x 4 Latin square with 28 d periods and four ruminally cannulated Finnish Ayrshire cows investigated the effect of protein supplements differing in amino acid (AA) profile and rumen undegradable protein content on postruminal AA supply and milk production. Mammary metabolism of plasma AA and other nutrients were also studied. The basal diet (Control; 13.4% crude protein) consisted of grass silage and barley in a ratio of 55:45 on a dry matter basis. The other three isonitrogenous diets (17.0% crude protein) were control + fishmeal (FM), control + soybean meal (SBM), and control + corn gluten meal (CGM). The protein supplements replaced portions of dry matter of the control diet maintaining the silage to barley ratio constant for all diets. Dry matter intake was limited to 95% of the preexperimental ad libitum intake and was similar (mean 19.8 kg/d dry matter) across the diets. Protein supplements increased milk, lactose, and protein yields but di...

Aim: The objective of this experiment was to evaluate the effect of the addition of tannin extract to Moringa and Indigofera leaf silages on their chemical composition, silage quality characteristics, and in vitro rumen fermentation parameters and digestibility.

Materials and Methods: Moringa and Indigofera leaves were cut (3 cm length) and added with either 0, 2, or 4% chestnut tannin in three replicates. The leaves were then inserted into lab-scale silos (1 L capacity) and kept for 30 days. Silage samples were subjected to silage quality determination, chemical composition analysis, and in vitro rumen fermentation and digestibility evaluation using a gas production technique. Data obtained were subjected to the analysis of variance with a factorial statistical model in which the first factor was different silage species and the second factor was tannin addition levels.

Results: Tannin addition at 4% dry matter (DM) increased neutral detergent insoluble crude protein (NDICP) and acid detergent insoluble CP (ADICP) of Indigofera silage. A similar response was observed in Moringa silage, but it required less tannin, i.e., 2% DM to increase its NDICP and ADICP. Moringa silage had lower pH than that of Indigofera silage (p<0.05), and tannin addition did not change pH of both Indigofera and Moringa silages. Higher addition level of tannin decreased total volatile fatty acid (VFA) and ammonia concentrations of both Indigofera and Moringa silages (p<0.05). A higher level of tannin addition reduced ruminal total VFA concentration, ammonia, in vitro DM digestibility, and in vitro organic matter digestibility of Indigofera and Moringa silages (p<0.05). Tannin addition also decreased ruminal methane emission of both Indigofera and Moringa silages (p<0.05).

Conclusion: Tannin extract can reduce proteolysis of high protein silage from Moringa and Indigofera leaves.

The feasibility and profitability of management-intensive grazing (MIG) in Atlantic Canada was studied. Productivity of MIG plus concentrate (1 kg:3 kg of milk) was compared with that of confinement feeding (Confined) using haylage (1996) or corn silage (1997) as 50% of dry matter (DM) in a total mixed ration (TMR). Each year, two groups of 10 Holsteins were used. In 1996, pasture CP content increased from 15.2 to 18.0% of DM, while those of acid detergent fiber (ADF) and neutral detergent fiber (NDF) decreased (33.6 to 23.8%, and 55.6 to 35.4%, respectively) between July 10 and August 28. In 1997, pasture crude protein (CP) content decreased from 30.0 to 15.7%, while ADF and NDF increased (24.9 to 35.8% and 53.5 to 67.4%, respectively) from June 16 to July 14. Because pasture biomass was reduced by winter-kill followed by drought in 1997, MIG cows were supplemented with TMR. Estimated pasture DM intakes ranged from 14.2 to 18.1 kg/d per cow. Milk yields averaged 29.5 and 30.4 +/- 0...

The objective of this study was to investigate the effects of starch varying in rate of fermentation and level of inclusion in the diet in exchange for fiber on methane (CH4) production of dairy cows. Forty Holstein-Friesian lactating dairy cows of which 16 were rumen cannulated were grouped in 10 blocks of 4 cows each. Cows received diets consisting of 60% grass silage and 40% concentrate (dry matter basis). Cows within block were randomly assigned to 1 of 4 different diets composed of concentrates that varied in rate of starch fermentation [slowly (S) vs. rapidly (R) rumen fermentable; native vs. gelatinized corn grain] and level of starch (low vs. high; 270 vs. 530g/kg of concentrate dry matter). Results of rumen in situ incubations confirmed that the fractional rate of degradation of starch was higher for R than S starch. Effective rumen degradability of organic matter was higher for high than low starch and also higher for R than S starch. Increased level of starch, but not sta...

The effects of exogenous proteolytic enzyme (EPE) on intake, digestibility, ruminal fermentation, and lactational performance were determined using 8 lactating Holstein cows in a double 4 x4 Latin square experiment with a 2 x2 factorial arrangement of treatments. Diets based on barley silage and alfalfa hay as the forage sources were formulated to maintain different forage to concentrate ratios [60:40 vs. 34:66, dry matter (DM) basis]. Four dietary treatments were tested: high forage (HF) without EPE (HF-EPE), HF with EPE (HF+EPE), low forage (LF) without EPE (LF-EPE), and LF with EPE (LF+EPE). The EPE, which contained proteolytic activity but negligible fibrolytic activity, was added to the concentrate portion of the diets after pelleting at a rate of 1.25 mL/kg of DM. Adding EPE to the diet increased total tract digestibilities of DM, organic matter, N, acid detergent fiber, and neutral detergent fiber, with larger increases in digestibility observed for cows fed LF+EPE. Effects o...

Four multiparous Holstein cows were used in a 4 x 4 Latin square experiment to study the effects of fat sources rich in omega-3 fatty acids on milk production and composition, follicular development, and prostaglandin secretion. All cows were fed a total mixed diet containing 60% grass silage and 40% concentrate. The four treatments were concentrates based either on Megalac, formaldehyde-treated whole linseed, a mixture (50:50, oil basis) of fish oil and formaldehyde-treated whole linseed, or no fat source in the concentrate but with 500 g per day of linseed oil being infused into the duodenum. Feed intakes and milk yield were similar among treatments. In general, the lowest digestibility was observed for the formaldehyde-treated whole linseed treatment. Feeding fish oil decreased milk fat and protein percentages. Alpha-linolenic acid increased from 1.0 to 13.9% of milk fatty acids with linseed oil infusion. This confirms the high potential to incorporate alpha-linolenic acid into m...