Higher Organic Matter Digestibility Research Articles

Effect of additives on fermentation characteristics, nutrient values and <i>in vitro</i> fermentation profile of <i>Neolamarckia cadamba</i> leaf silage

This study was designed to investigate the effects of additives on the ensiling characteristics of Neolamarckia cadamba leaf (NCL) silage. The NCL were allocated to six ensiling treatments, namely control (C-S), uncompacted (UC-S) (negative control), with the addition of sodium sulphite (S-S), with propionate (P-S), with citric acid plus sodium acetate (CA-S), and with glucose (G-S). Fermentation parameters, chemical compositions and in vitro fermentation profile of the silages were investigated after 60 days’ storage. Compared with the control, the application of additives improved dry matter recovery (DMR), while UC-S had a poorer DMR. All the silages increased in pH value and acetate content, except for P-S. Lactate concentration was higher in S-S and G-S, and lower in UC-S, P-S, and CA-S. P-S, CA-S, and G-S had increased water soluble carbohydrate (WSC) concentrations. Soluble crude protein was higher in UC-S and CA-S. All the treated silage had greater gas production at slower rates, except for S-S. The fermentation of S-S, P-S and CA-S resulted in higher content of short-chain fatty acids and microbial crude protein relative to UC-S. S-S (38.82%) and CA-S (37.89%) had higher organic matter digestibility relative to the control (36.43%). S-S (42.80%) and P-S (43.99%) had higher crude protein digestibility, which was lower in UC-S (30.73%) when compared with the control (37.74%). There was no difference in the predicted available energy of these silages. The low ammonium nitrogen ratio and the high proportion of true protein inferred that protein was well preserved in these silages, even the uncompacted silage. These results suggest that sulphite and organic acids, such as propionate and citrate, could be an option to improve the feed quality of NCL silage, and its great protein conservation deserves more attention. Keywords: feed quality, in vitro technique, Neolamarckia cadamba , ruminant nutrition, silage processing

Effect of dried Sesbania sesban leaves supplementation on milk yield, feed intake, and digestibility of Holstein Friesian X Zebu (Arado) crossbred dairy cows.

This experiment was conducted to investigate effect of dried Sesbania sesban leaves supplementation on milk yield, feed intake and digestibility of Holstein Frisian X Zebu (Arado) crossbred dairy cows. Twelve cows at midlactation (155.83 ± 4.49days of lactation), second parity, and 442.21 ± 3.40kg average live body weight were randomly assigned to one of four dietary treatments according to a randomized complete block design. Cows were blocked according to their daily milk yield into three blocks of four animals each. Cows were fed a basal diet (control) or a basal diet supplemented with 1.25kg/day dried Sesbania sesban leaves, 2kg/day dried Sesbania sesban leaves and 2.75kg/day dried Sesbania sesban leaves on a dry matter basis for 8weeks. Total dry matter intake, nutrient intake, milk yield, dry matter digestibility, and nutrient digestibility showed significant variation among treatments. Cows supplemented with the highest level of Sesbania sesban (2.75kg/day) had higher total dry matter and nutrient intake. Similarly, cows supplemented with 2 and 2.75kg/day had higher milk yield than the nonsupplemented cows (up to 11.3 and 16.2%, respectively). Digestibility was lower for the nonsupplemented cows compared to cows supplemented with 2 and 2.75kg/day dried Sesbania sesban leaves but statistically similar to the cows supplemented with 1.25kg/day dried Sesbania sesban leaves. Supplementation with 2.75kg/day Sesbania sesban resulted in higher organic matter digestibility (OMD) compared to the control. Crude protein digestibility (CPD), neutral detergent fiber digestibility (NDFD), and acid detergent fiber digestibility (ADFD) were significantly affected by Sesbania sesban supplementation. The nonsupplemented cows had lower CPD, NDFD, and ADFD. These results indicate that dried Sesbania sesban leaves supplementation to dairy increases total DM intake, digestibility, and milk yield.

Determination of Chemical, Nutritional and Fermentation Properties of Citrus Pulp Silages

This study was carried out to investigate the possibilities of making silage from fruit juice industry waste.For this purpose, orange, lemon and tangerine pulp silage quality have been determined by comparing silage with maize and beet pulp silage.Treatment groups; 1) orange, 2) tangerine, 3) lemon, 4) maize and 5) sugar beet pulp. The silages were evaluated after 2 months from ensiling in the following areas: subjective evaluation, pH, dry matter, organic matter, crude protein, acid detergent fiber, neutral detergent fiber, ether extract and energy values (metabolizable energy) and net energy for lactation were calculated. As a result, it was determined that fruit juice industry residues were lower in terms of dry matter, but they contained higher energy due to their high organic matter content, digestibility and low cellulose content. In addition, it was determined that citrus pulp was evaluated as silage without any contribution.

Comparative determination of digestibility and energy contents of Heliz and Parzuk with traditional forages by in vivo and in vitro methods

The aim of this study was to determine digestibility and energy contents of plants heliz (Prangos pabularia) and parzuk (Hippomarathrum microcarpum) with in vivo and in vitro methods and also to compare them to traditional. Seven male Red Karaman hoggets were used in the trial. Digestibilities of four different forages were determined with classical and two-stage digestibility methods. Moreover, energy contents of forages were also estimated using both digestibility values. In situ degradation characteristics of these forages were also evaluated. In the in vivo trial for digestibility, the degrees of digestibility of four different forage plants were determined by ‘’missing block trial pattern’’. In vivo organic matter digestibility (OMD) of parzuk and heliz (75.52% and 73.46%) were higher than those of dried meadow grass (68.94%) and dried alfalfa hays (65.81%), (P<0.05). These difference were reflected in energy contents and DE (digestible energy) (3.33 and 3.24Mcal/kg dry matter (DM)), ME (2.73 and 2.65 Mcal/kg) and NEL (net energy lactation) (1.73 and 1.68 Mcal/kg DM) values of parzuk and heliz were higher than those of meadow grass (3.04, 2.49 and 1.57 Mcal/kg DM) and dried alfalfa (2.90, 2.38 and 1.49 Mcal/kg DM) hays, (P<0.05). In the two-stage digestibility method, OMD values were 71.88, 68.85, 66.99 and 58.52% for parzuk, heliz, meadow grass hay and dried alfalfa hay, respectively (P<0.05) The highest OMD was observed in parzuk with two-stage digestibility method, while OMD of heliz and dried meadow grass were similar to that of parzuk, OMD of dried alfalfa was similar to that of dried meadow grass but less than those of parzuk and heliz (P<0.05). In in situ experiment, degradability of dried alfalfa, parzuk and heliz were rapid after 4 hours incubation but degradability of meadow grass hay were slow. Dry matter digestibility of meadow grass hay, dried alfalfa hay, parzuk and heliz was 72.45, 76.36, 88.36 and 84.21%, respectively at end of 48 hours incubation period (P<0.05). In conclusion, parzuk and heliz grown at highlands, in case of cultivation, these plants can be alternative forages to other high quality forages such as alfalfa hay.

Effect of Species on Nutritive Value and Methane Production of Citrus Pulps for Ruminants

The experiment was carried out to determine the effect of species on the nutritive value and methane production of citrus pulps. Species had a significant effects (P<0.001) on the chemical composition, gas production, methane production, metabolisable energy (ME) and organic matter digestibility (OMD) of citrus pulps. Crude protein (CP) content of Citrus paradise was significantly (P<0.001) higher than those of the other citrus species. Neutral detergent fiber (NDF) and acid detergent fiber (ADF) contents of Citrus sinensis and Citrus reticulata were significantly (P<0.001) lower than the others. Methane production from Citrus reticulata was significantly (P<0.001) higher than those of Citrus limon and Citrus paradise . The ME of pulp from Citrus reticulata was significantly (P<0.001) higher than that of Citrus limon pulp whereas OMD of pulp from Citrus reticulata was significantly (P<0.001) higher than those of pulps from Citrus limon and Citrus paradise . As conclusion, citrus pulps from different species have a high potential as forage for ruminant animals since citrus pulps have high ME and OMD. However, the CP contents of citrus pulps should be taken into consideration and diets should be fortified with additional CP sources to compensate for the low crude protein when citrus pulps are included into ruminant diets.

PENGARUH PEMBERIAN RUMPUT RAJA (Pennisetum purpupoides) DAN TEBON JAGUNG TERHADAP KECERNAAN BAHAN KERING DAN BAHAN ORGANIK PADA SAPI PO PEDET JANTAN

THE EFFECTS OF OFFERING KING GRASS (Pennisetum purpupoides) AND CORN STOVER ON DRY MATTER AND ORGANIC MATTER OF ONGOLE CROSS BREED STEER CALVES. A research has been conducted to evaluate the effects of offering king grass (Pennisetum purpupoides) and corn stover as ingredients for ration formulating on dry matter and organic matter digestibility of ongole cross breed steer calves. Five ongole cross breed steer calves with about 100 kg body weight were used in this experiment. Latin square design with 5 tereatments was used. The treatments were rasio of king grass and corn stover; R1 = 100% king grass, R2 = 75% king grass + 25% corn stover, R3 = 50% king grass + 50% corn stover, R4 = 25% king grass + 75% corn stover, R5 100% corn stover. The variables measured were dry matter and organic matter digestibility. Analysis of variance showed that there were no significant effect of treatments on dry metter and organic matter digestibility. Averages of dry matter digestibility during experiment ranged 56.27% - 59.48%. The highest was 59.48% for R5 (100% corn stover) and the lowest was 56.27% for R1 (100% king grass). Averages of organic matter ranged from 87.64% to 88.72%. The highest organic matter digestibility was on R4 (25% king grass + 75% corn stover) and the lowest organic matter digestibility was on R2 (75% king grass + 25% corn stover). It can be concluded that the best nutritive value was at combination of 25% king grass + 75% corn stover on dry matter and organic matter digestibility of ongole cross breed steer calves. keywords: king grass, corn stover, digestibility, dry matter, organic matter

The nutritive value of condensed wheat distillers solubles for cattle

The chemical composition and the energy and protein value of five batches of condensed distillers solubles (CDS) originating from wheat were determined. The net energy for lactation (NEL) was derived from digestion coefficients obtained with sheep. The true protein digested in the small intestine (DVE) and the rumen degradable protein balance (OEB) were based on the rumen degradation rate (kdD), the rumen undegradable fraction (U) and intestinal digestibility of undegraded protein (%DVBE) predicted by regression equations derived from a data set of 28 protein feeds with kdD, U and %DVBE determined in situ. The CDS is a by-product with a high, but very variable CP content (238 to 495 g/kg DM). The CP contained on average 81% amino acids, with glutamine as main component (on average 21.8% of CP) and a relatively good lysine proportion (3.0%). Further, CDS contains quite a lot of crude fat (mean±SD: 71±14 g/kg DM), glycerol (95±52 g/kg DM) and sugars (123±24 g/kg DM) resulting in a high organic matter digestibility (88.6±3.0%) and high NEL content (8.3±0.4 MJ/kg DM). The protein value showed a large variation, with DVE ranging from 122 to 244 g/kg DM and OEB from 50 to 204 g/kg DM. Wheat CDS is a rich source of minerals and trace elements with exception of calcium.

Frequent moving of grazing dairy cows to new paddocks increases the variability of milk fatty acid composition

The aim of this work was to investigate the variations of milk fatty acid (FA) composition because of changing paddocks in two different rotational grazing systems. A total of nine Holstein and nine Montbéliarde cows were divided into two equivalent groups according to milk yield, fat and protein contents and calving date, and were allocated to the following two grazing systems: a long duration (LD; 17 days) of paddock utilisation on a heterogeneous pasture and a medium duration (MD) of paddock utilisation (7 to 10 days) on a more intensively managed pasture. The MD cows were supplemented with 4 kg of concentrate/cow per day. Grazing selection was characterised through direct observations and simulated bites, collected at the beginning and at the end of the utilisation of two subsequent MD paddocks, and at the same dates for the LD system. Individual milks were sampled the first 3 days and the last 2 days of grazing on each MD paddock, and simultaneously also for the LD system. Changes in milk FA composition at the beginning of each paddock utilisation were highly affected by the herbage characteristics. Abrupt changes in MD milk FA composition were observed 1 day after the cows were moved to a new paddock. The MD cows grazed by layers from the bottom layers of the previous paddock to the top layers of the subsequent new paddock, resulting in bites with high organic matter digestibility (OMD) value and CP content and a low fibre content at the beginning of each paddock utilisation. These changes could induce significant day-to-day variations of the milk FA composition. The milk fat proportions of 16:0, saturated FA and branched-chain FA decreased, whereas proportions of de novo-synthesised FA, 18:0, c9-18:1 and 18:2n-6 increased at paddock change. During LD plot utilisation, the heterogeneity of the vegetation allowed the cows to select vegetative patches with higher proportion of leaves, CP content, OMD value and the lowest fibre content. These small changes in CP, NDF and ADF contents of LD herbage and in OMD values, from the beginning to the end of the experiment, could minimally modify the ruminal ecosystem, production of precursors of de novo-synthesised FA and ruminal biohydrogenation, and could induce only small day-to-day variations in the milk FA composition.

VLIV VEGETAČNÍHO STADIA VOJTĚŠKY SETÉ NA CHEMICKÉ SLOŽENÍ A IN SACCO STRAVITELNOST ORGANICKÉ HMOTY

The influence of the stage of maturity of alfalfa on the chemical composition and in sacco digestibility was studied in a laboratory experiment. Alfalfa plants were analysed in 8 vegetation stages harvested in regular intervals before the beginning of bud setting until the fall of blossoms. The contents of nitrogenous substances, fat, crude fibre, ADF, NDF, Ca, P, Na, K and Mg were determined in the samples, and using the in sacco method also the organic matter digestibility in the rumen. Further we assessed the energy content and calculated the N−free extractives (BNLV) value. In some stages the chemical changes were monitored in the whole plant. It was discovered that during vegetation there was a statistically significant increase in the crude fibre content and in the ADF and NDF fractions and a reduction in nitrogenous substances. A strong negative correlation was detected between the stage of maturity of alfalfa and content of crude protein and net energy for lactation (r = −0.97 and r = −0.92, respectively). In the individual stages of vegetation the differences in the content of nitrogenous substances, fibre and fat were statistically significant (P &lt; 0.05). The statistically highest content of crude protein (28.97%) was detected in the first stage before bud setting and the lowest (11.97%) in the stage after the fall of blossoms. Later vegetation also had a stronger depressive effect on the content of fat and NEL. The organic matter digestibility (P &lt; 0.05) was the lowest in alfalfa in the last stage of sampling (62.6%) when it reached a mere 85.99% of the digestibility at the beginning of bud setting. The highest organic matter digestibility (72.80%) was detected in a sample of young alfalfa prior to bud setting. In the experiment we confirmed a strong and negative correlation (r = −0.97) between the crude fibre content and organic matter digestibility. The correlation was also strong between the stage of maturity of alfalfa and the content of magnesium (Mg).

Efficiency to reach age of puberty and behaviour of buffalo heifers (Bubalus bubalis) kept on pasture or in confinement

In order to evaluate the influence of rearing system (free-ranging (FR) v. confinement (C)) on buffalo heifer efficiency to reach age of puberty and on behavioural and immune functions, two experiments were conducted from September 2010 to October 2011. In Experiment I, 32 subjects aged 8 to 9 months at the start of experiment were used. A total of 16 animals (group C) were group housed in an indoor slatted floor pen (4 m2/animal) with an outdoor paddock (4 m2/animal); 16 others grazed on a Mediterranean natural pasture of 40 ha (group FR). Behavioural data were collected and organic matter digestibility, blood metabolites and progesterone were determined. At the end of the experiment, a novel object test and a skin test were conducted, and the avoidance distance (AD) at the manger was measured. Free-ranging animals were able to express natural behaviours such as wallowing and grazing. C animals devoted more time to the novel object than FR animals, whereas AD at manger was lower in group FR than in group C (P<0.01). Cellular immune response was higher in FR heifers than in C animals (P<0.01). FR animals also showed a higher digestibility of organic matter (P<0.01). Heifers from group FR had higher plasma concentrations of non-esterified fatty acids (P<0.001) and lower concentrations of glucose than heifers from group C (P<0.001). C animals showed higher daily weight gains (P<0.01) and weight at the puberty (P<0.05), but there were no differences in terms of age of puberty between the two groups. The intakes of dry matter (DM), CP and energy to reach the age of puberty were similar in both groups. In order to verify whether the results obtained in Experiment I could be replicated in different rearing conditions (reduced pasture availability, different location and altitude), a second experiment was conducted on 26 animals, where only onset of age of puberty and metabolic profile were monitored. In Experiment II, 13 heifers grazed on a natural pasture of 5 ha, other 13 received the same space as indicated for Experiment I. Results from Experiment II generally confirmed those of Experiment I. Only the intakes of DM and energy to reach the age of puberty were higher in group C than in FR (P<0.001). A lower competition with human nutrition, reproductive performances similar to those shown by confined animals and the indications given by immune and behavioural variables, suggest that a free-range-based system may be conveniently used for buffalo heifer farming purposes.

Chemical composition and in vitro total gas and methane production of forage species from the Mid Rift Valley grasslands of Ethiopia

AbstractThere is increasing interest in sustainable land use in the tropics to optimize animal production while also reducing methane (CH4) emissions, but information on nutritive value and CH4‐emission potential of tropical forage species is limited. Samples of 24 grasses and five other forages were collected during the main rainy season on randomly positioned quadrats in semi‐arid grassland in the Mid Rift Valley of Ethiopia. Samples were pooled by species, analysed for chemical composition and incubated with rumen fluid to determine total gas and CH4‐emission potentials using a fully automated in vitro gas production apparatus. Organic matter digestibility (OMD) and metabolizable energy (ME) contents were calculated from chemical composition and gas production data. Large variability was observed among forages for all nutritional variables considered. The grasses Eleusine multiflora, Pennisetum stramineum, Dactyloctenium aegyptium, Eragrostis aspera, Cenchrus ciliaris and Eragrostis cilianensis showed relatively high OMD (68–72%) and ME values (9·1–10·2 MJ kg−1 dry matter). Melinis repens, E. multiflora and the non‐legume forb Zaleya pentandra showed relatively low CH4 to total gas ratios; these species may have potential for use in low CH4‐emission forage diets. Acacia tortilis fruits had high content of crude protein and moderate ME values, and may be an ideal feed supplement for the grazing ruminant. Sodium content was below the recommended level for ruminants in all the forage species. Overall, the pasture stand during the main growing season was evaluated as having moderate nutritional quality.

The variation in morphology of perennial ryegrass cultivars throughout the grazing season and effects on organic matter digestibility

AbstractThe grass plant comprises leaf, pseudostem, true stem (including inflorescence) and dead material. These components differ in digestibility, and variations in their relative proportions can affect sward quality. The objective of this study was to determine the change in the proportion and organic matter digestibility (OMD) of leaf, pseudostem, true stem and dead components of four perennial ryegrass cultivars (two tetraploids: Astonenergy and Bealey and two diploids: Abermagic and Spelga) throughout a grazing season. The DM proportions and in vitro OMD of leaf, pseudostem, true stem and dead in all cultivars were determined during ten grazing rotations between May 2011 and March 2012. There was an interaction between rotation and cultivar for leaf, pseudostem, true stem and dead proportions. In May and June, Astonenergy had the highest leaf and lowest true stem proportion (P &lt; 0·05). From July onwards, there was no difference in leaf or true stem proportion between cultivars. Bealey had the highest annual mean OMD (752 g kg−1) and Spelga the lowest (696 g kg−1; P &lt; 0·05). The OMD followed the order leaf &gt; pseudostem &gt; true stem &gt; dead. Bealey had the highest combined leaf and pseudostem proportion 0·92, which explains why it had the highest OMD. In this study, the tetraploid cultivars had the highest leaf and pseudostem proportion and OMD. For accurate descriptions of a sward in grazing studies and to accurately determine sward morphological composition, pseudostem should be separated from true stem, particularly during the reproductive stage when true stem is present.

Nutritive value, in vitro fermentation and methane production of perennial pastures as affected by botanical composition over a growing season in the south of Chile

Permanent pastures have been shown to produce similar herbage masses and nutrient contents to perennial ryegrass pastures. To the best of our knowledge, little research has been conducted on the ruminal fermentation of permanent pastures. Our objective was to evaluate the effect of botanical composition of four perennial pastures during a growing season in the south of Chile [winter, September 2010 ‘S1’; spring, November 2010 ‘S2’; and summer, January 2011 ‘S3’]: on in vitro fermentation products using a batch culture system. The perennial pastures studied included: permanent (PP), permanent fertilised (PFP) and renovated pastures (Lolium perenne and Trifolium repens pasture ‘RGWC’; Bromus valdivianus, Dactylis glomerata, Holcus lanatus, L. perenne and T. repens ‘MIXED’). There were strong interactions between pasture type and regrowth period for true organic matter, nitrogen (N) and neutral detergent fibre digestibility; total gas and volatile fatty acid (VFA) production; ammonia and microbial N. In general, all pasture treatments showed a high true organic matter digestibility (&gt;800 g/kg), and tended to decrease in S3. In vitro fermentation of PFP and RGWC produced the highest total VFA concentration during S1 and S2, and no differences among pastures were observed in summer. Propionate proportion of total VFA was affected by pasture type and regrowth period, being higher for RGWC and S1, respectively. In vitro microbial N was higher for MIXED in S1, and PFP in S2 and S3. No pasture and regrowth period effects were observed for methane production and its proportion of total gas production. These results indicate that the in vitro fermentation products of a permanent fertilised pasture reach similar levels to those obtained from a sown pasture, and thus may be considered as a sustainable alternative for grazing livestock systems.

Effect of water hyacinth (eichhornia crassipes) silage on intake and nutrient digestibility in cattle fed rice straw and cottonseed cake.

Four crossbred Sindhi heifers with an average body weight (BW) of 135 kg and a mean age of 17 months were used to investigate the effect of feeding different combinations of rice straw and ensiled water hyacinth (EWH) supplemented with a source of protein in the form of cottonseed cake (CSC) on intake and digestibility. Four treatments consisting of graded levels of EWH were arranged in a 4×4 Latin square. The levels of EWH were set at: 0 (EWH0), 15 (EWH15), 30 (EWH30), and 45% (EWH45) of an expected total dietary dry matter (DM) intake of 30 g total DM per kg BW per day. Rice straw was offered ad libitum, while CSC was given at a fixed level of 5 g DM/kg body weight (BW). Voluntary intake and digestibility were measured consecutively in the 4 experimental periods which each lasted 28 days. The crude protein (CP) content of EWH, rice straw and CSC were 174, 53 and 370 g/kg DM, respectively. Rice straw had the highest neutral detergent fibre (NDFom) content (666 g/kg DM), followed by EWH (503 g/kg DM) and the lowest content was 418 g/kg DM in the CSC. The actual EWH contents in the consumed diets were 0, 17, 32 and 52% for EWH0, EWH15, EWH30 and EWH45, respectively. Rice straw intake decreased with level of EWH offered from 3049 for EWH0 to 1014 g/day for EWH45. Crude protein intake was 16, 25 and 33% higher (p<0.001) in EWH15, EWH30 and EWH45 treatments, respectively, as compared to EWH0. Digestibility of organic matter (OM), CP, NDFom and acid detergent fibre (ADFom) increased with increasing level of EWH offered. The highest OM digestibility (72.2%) was found for treatment EWH45 and the lowest (47.4%) for treatment EWH0. In spite of similar dietary CP contents, CP digestibility increased by 21 (EWH15), 31 (EWH30) and 40% (EWH45) with increasing level of EWH in comparison with treatment EWH0. It is concluded that increasing level of EWH in cattle diets considerably improved CP intake and digestibility of nutrients.

The Nutritive Value of Live Yeast Culture (Saccharomyces cerevisiae) and Its Effect on Milk Yield, Milk Composition and Some Blood Parameters of Dairy Cows

This study was conducted to determine the nutritive value of live yeast culture (RumiSacc, Saccharomyces cerevisiae) and to investigate its effects on milk yield, milk composition and some blood parameters in lactating cows. Six multiparous Holstein cows were allocated to two groups of three cows and assigned randomly to one of two diets in a cross-over experiment. Daily 50 g RumiSacc was top dressed at the p.m. feeding for the treatment group. RumiSacc supplied a high protein and energy with high organic matter digestibility values (83.35%) determined by in vitro enzymatic analysis. Yeast culture supplementation significantly increased milk yield, tended to increase fat yield, protein yield and lactose yield of milk. Methylated fatty acid level of 18:3 (n-3) in milk fat was increased by yeast culture supplementation. The concentrations of methionine, phenyalanine, tyrosine, tryptophan and taurine were significantly increased with dietary inclusion of yeast culture. Live yeast culture supplementation did not affect other performance

In vitro fermentation patterns and methane production of sainfoin (Onobrychis viciifolia Scop.) hay with different condensed tannin contents

AbstractSainfoin (Onobrychis viciifolia Scop.) is a perennial legume recently reappraised for some positive characteristics leading to highly satisfactory animal performance. Sainfoin’s characteristics may be partly explained by the presence of moderate levels of condensed tannins (CTs) able to protect dietary protein from microbial degradation in the rumen. Decreased CH4 emissions have been reported for ruminants consuming CT‐containing forage. The aim of this study was to evaluate the effects of CT content on the in vitro fermentation characteristics and kinetics and methane production of four samples of O. viciifolia cut at different phenological stages. Sainfoin hays and one sample of alfalfa hay were incubated at 39°C in anaerobiosis using the in vitro gas production technique. The chemical composition, tannin content and fermentation characteristics and kinetics of sainfoin samples were significantly affected by phenological stage. After 48 h, the CH4 production in sainfoin hays showed a tendency to increase with the advancement of phenological stage [from 38·6 to 49·8 mL g−1 of degraded organic matter (OM)]. The best period to cut sainfoin for hay making is between early and late flowering, when the forage combines high OM digestibility, low CH4 production and more efficient microbial fermentation.

Enteric and manure-derived methane and nitrogen emissions as well as metabolic energy losses in cows fed balanced diets based on maize, barley or grass hay

Ruminant husbandry constitutes the most important source of anthropogenic methane (CH4). In addition to enteric (animal-derived) CH4, excreta are another source of CH4, especially when stored anaerobically. Increasing the proportion of dietary concentrate is often considered as the primary CH4 mitigation option. However, it is unclear whether this is still valid when diets to be compared are energy-balanced. In addition, non-structural carbohydrates and side effects on nitrogen (N) emissions may be important. In this experiment, diet types representing either forage-only or mixed diets were examined for their effects on CH4 and N emissions from animals and their slurries in 18 lactating cows. Apart from a hay-only diet, treatments included two mixed diets consisting of maize stover, pelleted whole maize plants and gluten or barley straw and grain and soy bean meal. The diets were balanced in crude protein and net energy for lactation. After adaptation, data and samples were collected for 8 days including a 2-day CH4 measurement in respiratory chambers. Faeces and urine, combined proportionately according to excretion, were used to determine slurry-derived CH4 and N emissions. Slurry was stored for 15 weeks at either 14°C or 27°C, and temperatures were classified as ‘cool’ and ‘warm’, respectively. The low-starch hay-only diet had high organic matter and fibre digestibility and proved to be equally effective on the cows’ performance as mixed diets. The enteric CH4 formation remained unaffected by the diet except when related to digested fibre. In this case emission was lowest with the hay-only diet (61 v. 88 to 101 g CH4/kg digested NDF). Feeding the hay diet resulted in the highest slurry-CH4 production after 7 weeks of storage at 14°C and 27°C, and after 15 weeks at 14°C. CH4 emissions were, in general, about 10-fold higher at 27°C compared with 14°C but only after 15 weeks of storage. Urinary N losses were highest with the barley diet and lowest with the maize diet. There was a trend towards similar differences in N losses from the slurry of these cows (significant at 14°C). However, contrary to CH4, slurry-N emissions seemed to be temperature-independent. In conclusion, energetically balanced diets proved to be widely equivalent in their emission potential when combining animal and their slurry, this even at a clearly differing forage : concentrate ratio. The variation in CH4 emission from slurry stored shortly or at cold temperature for 15 weeks was of low importance as such conditions did not support methanogenesis in slurry anyway.

An evaluation of two perennial ryegrass cultivars (AberDart and Fennema) for sheep production in the uplands

SUMMARYUnder lowland conditions there is evidence to indicate that animals consuming ryegrasses bred for elevated water-soluble carbohydrate (WSC) concentrations are able to utilize the protein in their diet more efficiently, resulting in increased live-weight gain, milk production and lower loss of N. The current study evaluated the effects on upland sheep production of grazing two cultivars of perennial ryegrass nominally differing in WSC content. Replicate plots (n=4) of a cultivar bred for elevated levels of WSC (AberDart) and a control cultivar (Fennema) were grazed by ewes and lambs (pre-weaning) and by lambs only (post-weaning). Target surface sward heights of 40 and 60–70 mm were maintained during the pre-weaning and post-weaning periods, respectively. No differences were found in the WSC concentration of the two swards during either the pre-weaning or post-weaning periods. However, cultivar AberDart had a significantly lower fibre concentration during both periods (P&lt;0·05), and a higher digestibility of organic matter in dry matter (DOMD) value during the post-weaning period (P&lt;0·05). There was no cultivar effect of treatment on lamb growth during the pre-weaning period, but lamb live-weight gain was significantly higher for those grazing AberDart than Fennema during the post-weaning period (200 g/d v. 125 g/d; s.e.d.=26·5 g/d; P&lt;0·01), leading to a greater proportion of lambs selected for slaughter by the end of September (0·99 v. 0·70 respectively; s.e.d.=0·062; P&lt;0·05). The improved performance for lambs grazing AberDart relative to those grazing Fennema indicates that advances in plant breeding have the potential to improve the efficiency and profitability of lamb production in the uplands. However, additional research is required to explore the extent to which growing conditions in marginal environments influence the expression of traits.

Comparison of In vitro Gas Production, Metabolizable Energy, Organic Matter Digestibility and Microbial Protein Production of Some Legume Hays

The aim of this study was to compare in vitro gas production kinetics, metabolizable energy (ME), organic matter digestibility (OMD) and microbial protein (MP) production of widely used legume hays in ruminant nutrition in Turkey. Gas production were determined at 0, 3, 6, 12, 24, 48, 72 and 96 h and their kinetics were described using the equation p = a+b (1-e -ct ). There were significant differences among legume hays in terms of chemical composition. The crude protein content of legume hays ranged from 11.7 to 18.6% of dry matter (DM); crude fat from 2.1 to 3.5% DM; neutral detergent fiber from 35.6 to 52.0% DM; acid detergent fiber from 32.0 to 35.5% DM and acid detergent lignin 1.7 to 11.0% DM. Total gas production after 96 h incubation ranged between 61.67 and 76.00 ml/0.200 g of substrate. At 24, 72 and 96 h incubation the total gas production for common vetch were significantly (p<0.01) higher than those of the other legume hays. The ME, OMD and MP of legume hays ranged from 9.09 to 11.12 MJ/kg DM, 61.30 to 75.54% and 90.35 to 138.05 g/kg DM, respectively. The ME, OMD and MP of common vetch was significantly (p<0.01) higher than those of the other hays due to low cell-wall contents and high crude protein. At the end of the experiment, differences in chemical composition of legume hays resulted in the differences in the in vitro gas production, gas production kinetics and the estimated parameters such as ME, OMD and MP. Common vetch can be recommended to hay producers and ruminant breeders, due to high ME, OMD and MP production.

Determination of Nutritive Value of Citrus Tree Leaves for Sheep Using In vitro Gas Production Technique

The nutritive values of leaves of Citrus grandis, Citrus aurantium, Citrus oranges, Citrus limon, and Citrus deliciosa were evaluated by chemical composition and in vitro gas production techniques. There were significant (p<0.001) differences among citrus species in terms of chemical composition. Crude protein (CP) contents ranged from 123.0 to 148.3 g/kg DM. Neutral detergent fibre (NDF) and acid detergent fibre (ADF) contents were varied with species in the range 219.4-355.4 and 215.0-278.8 g/kg DM respectively. Condensed tannin (CT) contents were ranged from 5.9 to 10.2 g/kg DM. The PEG addition significantly (p<0.001) increased the gas production and some estimated parameters of citrus tree leaves. However, species showed variable responses to polyethylene glycol (PEG) treatment. There were also significant (p<0.001) differences among species in terms of gas production and estimated parameters. The OMD and ME contents of citrus leaves without PEG supplementation were ranged from 66.5 to 73.3% and 9.8 to 10.9 MJ/kg DM respectively. The improvement in gas production, organic matter digestibility (OMD) and metabolizable energy (ME) with PEG emphasized the negative effect of tannins on digestibility. The increase (%) in the estimated OMD and ME contents ranged from 5.5 to 9.8% and 5.7 to 10.2% respectively. All citrus tree leaves studied in this experiment have potential nutritive values indicated by high crude protein content, OMD, ME and low fiber values.