Maize Silage Diets Research Articles

Assessing the Effects of Dietary Cadmium Exposure on the Gastrointestinal Tract of Beef Cattle via Microbiota and Transcriptome Profile.

Cadmium (Cd) is an environmental pollutant, widely existing in soil, and can be absorbed and accumulated by plants. Hunan Province exhibits the worst cadmium contamination of farmland in China. Ruminants possess an abundant microbial population in the rumen, which enables them to tolerate various poisonous plants. To investigate whether the rumen microbiota could respond to Cd and mitigate the toxicity of Cd-accumulated maize to ruminants, 6-month-old cattle were fed with 85.82% (fresh basis) normal whole-plant maize silage diet (CON, n = 10) or Cd-accumulated whole-plant maize silage diet (CAM, n = 10) for 107 days. When compared to the CON cattle, CAM cattle showed significantly higher gain-to-feed ratio and an increased total bacterial population in the rumen, but a decreased total bacterial population in the colon. CAM cattle had higher relative abundance of Prevotella and Lachnospiraceae ND3007 group in the rumen, and Lachnospiraceae NK4A136 group and Clostridia vadinBB60 group in the colon. Notably, microbial correlations were enhanced in all segments of CAM cattle, especially Peptostreptococcaceae in the jejunum. Transcriptome analysis revealed down-regulation of several immune-related genes in the rumen of CAM cattle, and differentially expressed genes in the rumen were mostly involved in immune regulation. These findings indicated that feeding Cd-accumulated maize diet with a Cd concentration of 6.74 mg/kg dry matter (DM) could stimulate SCFA-related bacteria in the rumen, induce hormesis to promote weight gain, and improve energy utilization of cattle.

Feasibility of feeding cadmium accumulator maize (Zea mays L.) to beef cattle: Discovering a strategy for eliminating phytoremediation residues

Eco-friendly and efficient strategies for eliminating cadmium (Cd) phytoremediation plant residues are needed. The present study investigated the feasibility of feeding Cd accumulator maize to beef cattle. In total, 20 cattle at 6 months of age were selected and randomly allocated into two groups fed with 85.82% (fresh basis) Cd accumulator maize (CAM) or normal maize (control [Con]) silage diets for 107 d. Feeding CAM did not affect the body weight (P = 0.24), while it decreased feed intake and increased feed efficiency of beef cattle (P < 0.01). Feeding CAM increased serum concentrations of immunoglobulin A and G, complement 3 and 4, blood urea nitrogen, and low-density lipoprotein cholesterol, decreased serum concentrations of interleukin-6 and lipopolysaccharide (P < 0.05), and caused wider lumens in the renal tubules. The Cd residue in meat was 7 μg/kg beyond the restriction for human food. In the muscle, the unsaturated fatty acids (t11C18:1 and C20:4), Lys, Arg, Pro, and Cys were decreased, while the saturated fatty acids (C10:0, C12:0, and C17:0) and Leu were increased (P < 0.05). Therefore, at the current feeding level, phytoremediation maize increased the feed efficiency of beef cattle, but did present risks to cattle health and production safety, and decreased the meat nutrition and flavor. Further research must be performed to determine whether a lower proper dose of phytoremediation maize and an appropriate feeding period may be possible to ensure no risk to cattle health and the supply of safe meat for humans.

Feeding of vegetable waste silage to lambs by replacing maize silage

ABSTRACT The study examined the vegetable waste (VW) silage as feedstuff for lambs. Therefore, mechanically shredded VW was ensiled solely (T0) or by adding molasses (95:5 ratio; T1), or molasses and either wheat bran (T2) or rice polish (T3) or rice straw (T4) at an 85:5:10 ratio in 5 replicates for 45 days for evaluation. Then, the maize silage diet of two of the three groups of lambs (5 each) of 9.92 (±1.25) kg live weight (LW) was replaced with T4 silage at 50% and 100% on a fresh basis for 90 days and supplemented with a concentrated mixture at 1.5% of LWs. The significantly different pH (5.88, 5.21, 4.34, 4.33 and 4.23, respectively), lactic acid bacteria (not detected, 5.81, 6.51, 7.48 and 6.04 log10 cfu/g, respectively), and total volatile fatty acids (21.0, 29.2, 32.4, 36.0 and 32.0 mM/L, respectively) (P < .01) indicated that T2, T3 and T4 were of good quality silage. The dry matter intake and gain of lambs fed 100% T4 silage were significantly (P < .01) higher than others (2.30, 2.30 and 2.72% LW, respectively; 110, 128 and 141 g/d, respectively). It may be concluded that T4 silage may produce higher LW gain in lambs than maize silage.

Cotton cake as an economically viable alternative fibre source of forage in a high-concentrate diet for finishing beef cattle in feedlots.

Cotton cake can be a sustainable and economically viable alternative to maize silage as an effective fibre source in the finishing diet of feedlot beef cattle. Thus, the objective was to evaluate the economic viability and the productive performance of Nellore steers finished in feedlots using cotton cake as a source of fibre, replacing maize silage in the diet. Twenty-four non-castrated Nellore steers, with an average weight of 377.8kg and an age of approximately 24months, kept in individual pens, were used. The diet was 30% roughage, in the form of maize silage, and a diet without forage containing 30% cotton cake as an effective fibre source, based on dry matter. The design used was completely randomised with two treatments and 12 replications. Effects (p < 0.05) of the dietary fibre source were observed for final body weight (BW), total weight gain, hot carcass weight (HCW) and carcass yield (CY). Revenue and net margin were higher for the treatment with cotton cake. The corn silage diet promoted higher total costs per animal (U$ 408.41 vs. U$ 336.06) and daily costs (U$ 3.65 vs. U$ 3.00). Greater differences were observed between fibre sources for the concentrate cost, and the maize silage diet had a cost U$ 98.29 higher than the treatment with cotton cake (U$ 314.04 vs. U$ 215.75). The cotton cake treatment had a higher cost of U$106.98/animal for the net margin. Cotton cake is a viable alternative and can be used as a source of fibre in forage-free diets without affecting production performance, promoting benefits in economic performance for finishing beef steers in feedlots.

Fatty acid profile and beef quality of Nellore and Angus bulls fed whole shelled corn

This study aimed to evaluate the quality traits and fatty acid profile of beef from Nellore and Angus bulls fed whole shelled corn (WSC) and ground corn plus maize silage (GC) diets. Eighteen Nellore and 18 Angus young bulls [381 ± 12 kg initial body weight (BW) and an average age of 20 ± 1.9 months] were used in a completely randomized design using a 2 × 2 factorial arrangement and were slaughtered at a final BW of 451.5 kg and 545.5 kg, respectively. Twenty–four hours after slaughter, samples of longissimus thoracis muscle were collected for the analysis of lipid oxidation, color, fatty acid profile, shear force, and cooking loss. There was no effect of diet × breed interaction on meat color, lipid oxidation, shear force, and cooking loss. Angus beef had lower shear force (p < 0.05) than Nellore beef and had a greater concentration of linoleic acid and polyunsaturated fatty acids (PUFA) (p < 0.01). Beef of bulls fed WSC tended to have greater concentration of CLA C18:2c9t11 (p = 0.09), greater concentration of CLA C18:2t10c12 (p = 0.01), and PUFA (p = 0.05), and consequently, higher oxidation levels. Angus bulls produced beef with greater tenderness and PUFA concentration. The results of fatty acid show a possible change in biohydrogenation when animals are fed the WSC diet, reducing lipogenesis, as this diet increases the C18:2t10c12 content.

Effect of feeding hay vs. silages of various types to dairy cows on feed intake, milk composition and coagulation properties

This research paper addresses the hypotheses (1) that milk produced from hay-fed cows differs from that of silage-fed cows and (2) that silage type has an important impact, too. Four diets differing in forage type but with equal estimated milk production potential and a forage:concentrate ratio of 0.85 : 0.15 were compared regarding their effect on feed intake, milk yield and milk properties. The forages tested were hay, grass silage, conventional short-chopped and long-chopped maize silage subjected to a novel processing technology (Shredlage®). Twenty-four dairy cows were fed two of the four diets in two consecutive runs in an incomplete (4 × 2) Latin-square design (n = 12 per diet). Each experimental period lasted 22 d, with 12 d of adaptation and 10 d of sampling. During sampling, feed intake and milk yield were recorded daily, milk composition and coagulation properties were determined four times. The composition of the diet ingredients was analysed weekly. Data were analysed with a mixed model considering feed, period and their interaction as fixed effects. Stage of lactation, milk yield and milk composition from the pre-experimental period were used as covariates in the model. Dry matter intake was lower with the long-chopped processed maize silage compared to the other three groups. There were some diet differences in intakes of net energy for lactation and absorbable protein in the duodenum, but this did not result in changes in milk yield. The milk fat content was higher with the grassland-based diets compared to the maize silage diets. No treatment effect on milk acidity and rennet coagulation properties was observed. In conclusion, there were no indications for specific physico-chemical properties of milk from a hay-based diet, and maize processing technology was not of large effect either. Future investigations should focus on sensory differentiation of the milk produced with different forages.

The effect of silage type on animal performance, energy utilisation and enteric methane emission in lactating dairy cows

The present study aimed to investigate the effect of silage type on dry matter (DM) intake, nutrient digestibility, energy utilisation and methane (CH4) emission. Six late lactating Holstein dairy cows were used in a replicated 3 × 3 Latin square design study with three treatments (grass silage (GS), maize silage (MS) and whole-crop wheat silage (WCWS)) and three periods (3 weeks/period). All animals were offered forage ad libitum and 5.55 kg/day of a concentrate supplement, which contained (DM basis) 66.0% rapeseed meal, 28.3% soyabean meal and 5.7% a mineral/vitamin supplement. During each period, animals were subject to digestibility, CH4 and heat production measurements during the final 6 days using calorimeter chambers. The results demonstrated that total DM intake for MS and WCWS diets were higher (P &amp;lt; 0.001) than for the GS diet. Faecal energy and heat production loss for the GS diet were lower (P &amp;lt; 0.01) than for MS and WCWS diets. In contrast, cows fed the GS diet had higher (P &amp;lt; 0.05) urine energy loss compared with MS and WCWS diets. In comparison with the GS and MS diets, WCWS diet produced a lower CH4 loss per kg DM and organic matter intake (P &amp;lt; 0.01), and CH4 energy output as a proportion of gross energy and metabolisable energy intake (P &amp;lt; 0.05). The present study demonstrates that choice of forage types affects energy utilisation and CH4 emission in dairy cows.

THE ECONOMIC ANALYSIS OF THE USE OF NONTRADITIONAL FEED IN THE DIET OF DAIRY ANIMALS IN FAYOUM GOVERNORATE

This research aims to study the economic impact of using traditional diets and non-traditional diets containing rice straw treated with ammonia and maize silage to feed dairy cattle, on dairy production. The study results showed that: - The total additional economic returns achieved as a result of the use of rice straw treated with ammonia amounted to 2602.9, and 2020.4 pounds, and as a result of the use of maize silage amounted to 3501.7, 2009.0 pounds during the season for the buffaloes and cows, respectively. - the ratio of total return value to total feeding costs after using rice straw treated with ammonia is greater compared to that used traditional feed, where amounted to about 2.29, 2.32 with an increase of about 0.84, 1.02 pounds per head of buffalo and cattle respectively, and it amounted to about 2.60, 2.24 after the use of maize silage, with an increase of about 1.15, 0.94 pounds per head of buffalo and cattle respectively. - The estimated production function for buffalo indicate that the production elasticity is about 1.41, which means the existence of increasing return to scale. The production function is statistically significant at 1%, with R2 equal to 0.86. - The optimum production that minimize the cost and maximize the profit per head of buffalo during the season is estimated to be about 2.746, 3.627 tons in the case of using traditional diet, while in the case of using rice straw treated with ammonia it is about 2.765, 3.955 tons, and in the case of using maize silage is about 1.843, 3.609 tons. - The optimum production that minimize the cost and maximize the profit per head of cow during the season is also estimated to be about 1.477, 1.977 tons in the case of using traditional diet, while in the case of using rice straw treated with ammonia is about 1.077, 1.893 tons, and in the case of using maize silage is about 1.230, 2.016 tons. - The total estimated economic impact in the case of using rice straw treated with ammonia diet, is expected to increase milk production in the country by 465.07, 233.51 thousand tons for buffalo, cows, respectively. In the case of of using maize silage diet, the expected increase in milk production is around 682.71, 293.09 thousand tons for buffalo, cows, respectively. At the level of Fayoum governorate, the increase is about 26.02, 11.22 thousand tons for buffalo, cows, respectively, in the case of using diet containing rice straw treated with ammonia, while in the case of using diet containing maize silage, the expected increase is around 38.2, 14.09 thousand tons for buffalo, cows, respectively. In light of the previous findings, the study recommends the following: - There is a need for efforts from the extension and research institutions and media channels to encourage adoption of the use of non-traditional feed at the national level. - Raising awareness of farmers and breeders about the importance of non-traditional feeds in reducing feeding costs and increasing economic returns, in addition to increasing the national output of milk. - There is a need to expand the use of rice straw treated with ammonia and maize silage, which leads to the reduction of area allocated for clover and increase area for wheat production, thereby reducing its imports. - The study recommends expanding non-traditional feed mills in countryside of Egy

An examination of two concentrate allocation strategies which are based on the early lactation milk yield of autumn calving Holstein Friesian cows

The objective of this experiment was to compare the effects of two concentrate feeding strategies offered with a grass silage and maize silage diet on the dry matter (DM) intake, milk production (MP) and estimated energy balance of autumn calved dairy cows. Over a 2-year period, 180 autumn calving Holstein Friesian cows were examined. Within year, cows were blocked into three MP sub-groups (n=9) (high (HMP), medium (MMP) and low (LMP)) based on the average MP data from weeks 3 and 4 of lactation. Within a block cows were randomly assigned to one of two treatments (n=54), flat rate (FR) concentrate feeding or feed to yield (FY) based on MP sub-group. Cows on the FR treatment were offered a fixed rate of concentrate (5.5 kg DM/cow per day) irrespective of MP sub-group. In the FY treatment HMP, MMP and LMP cows were allocated 7.3, 5.5 and 3.7 kg DM of concentrate, respectively. The mean concentrate offered to the FR and FY treatments was the same. On the FR treatment there was no significant difference in total dry matter intake (TDMI, 17.3 kg) between MP sub-groups. In the FY treatment, however, the TDMI of HMP-FY was 2.2 kg greater than MMP-FY, and 4.5 kg greater than LMP-FY (15.2 kg DM). The milk yield of LMP-FR was 3.5 kg less than the mean of the HMP-FR and MMP-FR treatments (24.5 kg). The milk yield of the HMP-FY treatment was 3.6 and 7.9 kg greater than the MMP-FY and LMP-FY treatments, respectively. The difference in MP between the HMP sub-groups was 2.6 kg, which translates to a response of 1.4 kg of milk per additional 1 kg of concentrate offered. There was no significant difference in MP between the two LMP sub-groups; however, MP increased 0.8 kg per additional 1 kg of concentrate offered between cows on the LMP-FR and LMP-FY treatments. The estimated energy balance was positive for cows on the LMP-FR treatment, but negative for cows on the other treatments. The experiment highlights the variation within a herd in MP response to concentrate, as cows with a lower MP potential are less responsive to additional energy input than cows with a greater MP potential. Cows with a greater MP capacity did not substitute additional concentrate for the basal forage, which indicates an additional demand for energy based on ability of individual cows to produce milk.

Effect of group size and maize silage dietary levels on behaviour, health, carcass and meat quality of Mediterranean buffaloes

The effects of different dietary levels of maize silage (10% v. 36% DM) and group size (7 v. 14 animals) were assessed on growth performance and in vivo digestibility of 28 male fattening buffaloes. In addition, the effects of diet on meat quality and group size on behaviour and immune response were separately evaluated. Animals were weighed and assigned to three groups. The high silage – low size group (HL) was fed a total mixed ration (TMR) containing 36% DM of maize silage and consisted of seven animals (age 12.7±2.6 months; BW 382.2±67.7 kg at the start of the study). The low silage – low size group (LL) was fed a TMR containing 10% DM of maize silage and consisted of seven animals (age 13.0±2.7 months; BW 389.4±72.3 kg). The high silage – high size group (HH) was fed the 36% maize silage DM diet and consisted of 14 animals (age 13.9±3.25 months; BW 416.5±73.9 kg). Total space allowance (3.2 indoor+3.2 outdoor m2/animal) was kept constant in the three groups, as well as the ratio of animals to drinkers (seven animals per water bowl) and the manger space (70 cm per animal). Growth performance, carcass characteristics and digestibility were influenced neither by dietary treatment nor by group size, even if the group fed 36% maize silage diet showed a higher fibre digestibility. No effect of diet was found on meat quality. Group size did not affect the behavioural activities with the exception of drinking (1.04±0.35% v. 2.60±0.35%; P<0.01 for groups HL and HH, respectively) and vigilance (2.58±0.46% v. 1.20±0.46%; P<0.05 for groups HL and HH, respectively). Immune responses were not affected by group size.

Effects of forage type and extruded linseed supplementation on methane production and milk fatty acid composition of lactating dairy cows

Replacing dietary grass silage (GS) with maize silage (MS) and dietary fat supplements may reduce milk concentration of specific saturated fatty acids (SFA) and can reduce methane production by dairy cows. The present study investigated the effect of feeding an extruded linseed supplement on milk fatty acid (FA) composition and methane production of lactating dairy cows, and whether basal forage type, in diets formulated for similar neutral detergent fiber and starch, altered the response to the extruded linseed supplement. Four mid-lactation Holstein-Friesian cows were fed diets as total mixed rations, containing either high proportions of MS or GS, both with or without extruded linseed supplement, in a 4×4 Latin square design experiment with 28-d periods. Diets contained 500g of forage/kg of dry matter (DM) containing MS and GS in proportions (DM basis) of either 75:25 or 25:75 for high MS or high GS diets, respectively. Extruded linseed supplement (275g/kg ether extract, DM basis) was included in treatment diets at 50g/kg of DM. Milk yields, DM intake, milk composition, and methane production were measured at the end of each experimental period when cows were housed in respiration chambers. Whereas DM intake was higher for the MS-based diet, forage type and extruded linseed had no significant effect on milk yield, milk fat, protein, or lactose concentration, methane production, or methane per kilogram of DM intake or milk yield. Total milk fat SFA concentrations were lower with MS compared with GS-based diets (65.4 vs. 68.4g/100g of FA, respectively) and with extruded linseed compared with no extruded linseed (65.2 vs. 68.6g/100g of FA, respectively), and these effects were additive. Concentrations of total trans FA were higher with MS compared with GS-based diets (7.0 vs. 5.4g/100g of FA, respectively) and when extruded linseed was fed (6.8 vs. 5.6g/100g of FA, respectively). Total n-3 FA were higher when extruded linseed was fed compared with no extruded linseed (1.2 vs. 0.8g/100g of FA, respectively), whereas total n-6 polyunsaturated FA were higher when feeding MS compared with GS (2.5 vs. 2.1g/100g of FA, respectively). Feeding extruded linseed and MS both provided potentially beneficial decreases in SFA concentration of milk, and no significant interactions were found between extruded linseed supplementation and forage type. However, both MS and extruded linseed increased trans FA concentration in milk fat. Neither MS nor extruded linseed had significant effects on methane production or yield, but the amounts of supplemental lipid provided by extruded linseed were relatively small.

Inclusion of glycerol in forage diets increases methane production in a rumen simulation technique system

We hypothesised that the inclusion of glycerol in the forage diets of ruminants would increase the proportion of propionate produced and thereby decrease in vitro CH₄ production. This hypothesis was examined in the present study using a semi-continuous fermentation system (rumen simulation technique) fed a brome hay (8·5 g) and maize silage (1·5 g) diet with increasing concentrations (0, 50, 100 and 150 g/kg DM) of glycerol substituted for maize silage. Glycerol linearly increased total volatile fatty acids production (P<0·001). Acetate production was quadratically affected (P=0·023) and propionate and butyrate production was linearly increased (P<0·001). Glycerol linearly increased (P=0·011) DM disappearance from hay and silage. Crude protein disappearance from hay was not affected (P=0·789), but that from silage was linearly increased (P<0·001) with increasing glycerol concentrations. Neutral-detergent fibre (P=0·040) and acid-detergent fibre (P=0·031) disappearance from hay and silage was linearly increased by glycerol. Total gas production tended to increase linearly (P=0·061) and CH₄ concentration in gas was linearly increased (P<0·001) by glycerol, resulting in a linear increase (P<0·001) in mg CH₄/g DM digested. Our hypothesis was rejected as increasing concentrations of glycerol in a forage diet linearly increased CH₄ production in semi-continuous fermenters, despite the increases in the concentrations of propionate. In conclusion, this apparent discrepancy is due to the more reduced state of glycerol when compared with carbohydrates, which implies that there is no net incorporation of electrons when glycerol is metabolised to propionate.

Effect of forage source and a supplementary methionine hydroxyl analogue on rumen fermentation parameters in lactating dairy cows offered a low crude protein diet

The objective of this experiment was to evaluate the effects of forage source (grass silage (GS) or maize silage (MS)) and a supplementary methionine hydroxyl analogue (HMBi) on rumen fermentation parameters in dairy cows offered a low-crude protein (CP) diet. Four lactating dairy cows permanently fitted with rumen cannulae were assigned to 1 of 4 diets in a 2×2 factorial, Latin square design. Diets were isoenergetic and isonitrogenous and were offered once daily as a total mixed ration. Rumen samples were taken every 2h over 48h for analysis of pH, volatile fatty acids (VFA), total lactic acid and NH3-N. Mean pH (6.21±0.03) and nadir pH (5.64±0.12) were not affected by dietary treatment. Animals offered GS based diets had higher VFA (113.69 vs. 107.55±1.53mmol/L) and NH3-N (62.82 vs. 55.54±2.38mg/L) concentrations vs. those offered MS diets. No effect of supplementary HMBi on rumen pH, VFA or NH3-N was detected in this study.

Carcass fat partitioning and meat quality of Alentejana and Barrosã young bulls fed high or low maize silage diets

This study assessed the effect of breed and diet on carcass composition, particularly fat partitioning, and meat quality in young bulls. An experiment with forty young bulls from two phylogenetically distant Portuguese bovine breeds, Alentejana and Barrosã, fed two diets with different maize silage to concentrate ratios, but isoenergetic and isonitrogenous, was carried out until the animals reached 18months of age. In the longissimus lumborum muscle, Barrosã bulls fed the low silage diet had the highest intramuscular fat (IMF) content. Bulls fed the low silage diet also had the highest IMF content in the semitendinosus muscle. Diet determined the proportions of total visceral fat and individual fat depots. Under these experimental conditions, it was shown that the genetic background is a major determinant of carcass composition and meat quality, and that the dietary differences studied had limited effect on carcass composition.

Fatty acids profile of milk from cows fed different maize silage levels and extruded soybeans

The objective of this study was to evaluate the effects of two levels of maize silage and extruded soybeans supplementation on fatty acid profile in milk fat of dairy cows. Eight Holstein cows were distributed in a double 4x4 Latin Square design with a factorial arrangement. The treatment groups were: high maize silage and low lipid, high maize silage and high lipid, low maize silage and low lipid and low maize silage and high lipid. The experimental periods lasted 21 days. Milk samples were collected on days 18 and 19 of each experimental period. The increase of lipid contents in high and low maize silage diets decreased short chain fatty acids concentrations (C4:0 - C12:0). The conjugated linoleic acid content (cis-9 trans-11 C18:2) increased from 3.72 to 4.85, and 4.6 to 5.89mg/g, when extruded soybeans was used in high and low level of corn silage, respectively. The increase in dietary lipids content resulted in higher trans-11 C18:1 fatty acid concentration. Fatty acid trans-10 C18:1 tended to increase with the elevation of the lipids content in the diet. There was significant correlation between trans-10, cis-12 C18:2 and milk fat percentage. The extruded soybeans supplementation decreased shortchain fatty acids and palmitic acid in milk. In addition, this oilseed enhanced the concentration of conjugated linoleic acid (C18:2 cis-9 trans-11) and vaccenic acid, which improved the milk quality for the human health.

Methane conversion rate of bulls fattened on grass or maize silage as compared with the IPCC default values, and the long-term methane mitigation efficiency of adding acacia tannin, garlic, maca and lupine

Abating enteric methane in ruminants by feeding is considered promising, but long-term assessments are lacking. Thirty-six growing bulls were allocated to six treatments and received either grass or maize silage and concentrate. The maize silage diet was also supplemented with acacia tannin extract, garlic bulbs, maca hypocotyls, or lupine seeds. At ages of 5, 9 and 11 months, enteric methane was measured in open circuit respiratory chambers along with feed intake and excretion. Ruminal fluid was collected at slaughter. Slurry-derived methane was determined while stored at 14 °C and 27 °C for 15 weeks. Exchanging maize for grass silage increased enteric methane only on one occasion. Total system methane emission was similar between grass- and maize-silage fed bulls. Tannin decreased methane by up to 36% and, most importantly, this suppression persisted throughout the entire experiment. Tannins did not alter slurry-derived methane. Enteric methane conversion rate and methane conversion factors in slurry were always below the IPCC default values. Grass silage increased fibre digestibility and numbers of total and cellulolytic Bacteria. The study demonstrated a long-term efficacy of acacia tannin in mitigating methane. Further, the results suggest that IPCC appears to overestimate methane from growing cattle fattened on typical European diets.

Leviers d’action pour réduire la production de méthane entérique par les ruminants

Cet article fait le point des connaissances sur différentes pistes pour réduire la production de méthane entérique par les ruminants,en privilégiant les approches in vivo, et évalue les possibilités d'application pratique. Il est connu que l'accroissement du pourcentagede concentré dans la ration réduit la production de méthane par kg de matière sèche ingérée. Cet effet est toutefois plus sensible pourdes proportions élevées de concentré. Les céréales diminuent plus la production de méthane que les concentrés riches en fibres.L'addition de lipides à la ration a un effet significatif pour réduire les émissions de méthane. Parmi les fourrages, l'ensilage de maïsentraîne des émissions plus faibles que l'ensilage d'herbe ou le foin ; mais les différences induites entre stades de végétation de l'herbeou entre graminées et légumineuses sont faibles, et parfois controversées. De très nombreux extraits de plantes et autres additifsaux modes d'action divers ont été testés. Les plantes riches en tannins et les tannins extraits des plantes sont efficaces pour réduire leméthane mais le risque de diminution de la digestibilité de la ration doit être considéré. Les autres additifs nécessitent des étudessupplémentaires pour attester leur efficacité sur le long terme. Parmi les biotechnologies, celles visant à réorienter la productiond'hydrogène vers d'autres produits que le méthane sont séduisantes, mais pas encore mises au point. L'accroissement du niveau deproduction des animaux entraîne une réduction de la production de méthane qui est particulièrement marquée quand elle estrapportée au kg de lait ou de viande. Enfin, il y a des différences entre animaux dans l'efficacité globale de production, appréciée parl'ingestion rapportée à un même niveau de production. Les animaux les plus efficaces produisent moins de méthane par kg de lait oude viande. L'article met l'accent sur la nécessité de ne pas considérer la diminution du méthane seule, mais d'évaluer l'efficacité desstratégies proposées sur l'ensemble des GES.

Fatty acid profile and oxidative stability of the perirenal fat of bulls fattened on grass silage and maize silage supplemented with tannins, garlic, maca and lupines

Carcass fat composition of cattle fed a forage-based diet might be inferior with maize silage compared to grass-silage based systems. This was quantified using complete diets with concentrate. To test whether supplements may influence carcass fat properties as well, the maize-silage diet was additionally supplemented either with Acacia mearnsii tannins, garlic, maca or lupines, feeds rich in secondary metabolites. The perirenal fat of 6 × 6 bulls fed these six diets was analysed for fatty acid profile and shelf life. The n−6/ n−3 ratio was always higher than 11 with the maize silage treatments and 2 with grass silage. The supplements did not affect the occurrence of biohydrogenation intermediates, including rumenic acid. Shelf life, being twice as long with maize compared to grass silage, was either unaffected or tended to be impaired, especially with supplementary garlic. Overall, supplementation was not efficient in improving carcass fat properties of maize-silage fed bulls.

Nutrients intake, digestibility, nitrogen balance and growth performance of sheep fed different silages with or without concentrate

The experiment was conducted to investigate the influence of maize (Zea mays), sorghum (Sorghum bicolor) and millet (Pennisetum americannum) silages with or without concentrate on nutrients intake, digestibility, nitrogen balance and weight gain in Sipli sheep. Six experimental diets were formulated having 100% maize silage (MS), maize silage and concentrate as 50:50 (MSC), 100% sorghum silage (SS), sorghum silage and concentrate as 50:50 (SSC), 100% millet silage (MiS) and millet silage and concentrate as 50:50 (MiSC), respectively. For this purpose, 24 Sipli lambs were randomly allotted to six experimental diets in a completely randomized design for 90 days, four lambs per diet. The results indicated that among various silage diets, lambs fed MS diet consumed higher dry matter (DM) than those fed SS and MiS diets. Likewise, lambs offered MSC had higher dry matter intake than those fed SSC and MiSC diets. Crude protein (CP) and neutral detergent fibre (NDF) consumed by the lambs also followed the similar trend. Higher DM, CP and NDF digestibilities were also observed in lambs fed MS and MSC diets than those fed SS, SSC, MiS and MiSC diets. Overall digestibilities of DM, CP and NDF were higher in experimental diets containing silage with concentrate. Lambs fed MS diet had 2.79 g/day and 4.45 g/day higher N retention than those fed SS and MiS, respectively. Similarly, lambs fed MSC diet had 2.24 g/day and 5.12 g/day higher N retention than those fed SSC and MiSC diets, respectively. The results showed that lambs fed MSC gained more daily weight gain had better feed conversion ratio than those fed MS, SS, SSC, MiS and MiSC diets. The findings of the present study indicated that lambs fed MSC diet had higher nutrients intake, digestibility, nitrogen balance and weight gain.

RUMINAL FERMENTATION KINETICS OF MORINGA AND PELTIPHYLLUM SUPPLEMENTS DURING EARLY INCUBATION PERIOD IN THE IN VITRO READING PRESSURE TECHNIQUE

This experiment was aimed to observe rumen fermentation kinetics of alternative supplements, i.e.Moringa oleifera and Peltiphyllum peltatum leaves added to maize silage diet as compared to aconventional supplement (barley-soya). A total of six treatments were investigated in the present study,which consisted of: maize silage (A), M. oleifera (B), P. peltatum (C), maize silage + concentrate (56:44,w/w; D), maize silage + M. oleifera (56:44, w/w; E), and maize silage + concentrate + P. peltatum(47:37:16, w/w/w; F). The feeds were incubated in vitro in three replicates (completely randomized)using the Reading Pressure Technique system. Approximately 800 mg of the feeds were mixed by 75 mlof buffered rumen liquor. The incubation was carried out up to 12 h in bottles and gas pressure wasrecorded and released in regular intervals. Repeated sampling was conducted for analysis offermentation products at 1, 6 and 12 h of incubation period. The results showed that the nutritionalquality of Moringa and its fermentation pattern was comparable to that of barley-soya concentrate. PlainMoringa incubation resulted the highest production of iso-SCFA and soluble protein concentrationamong all treatments after 12 h incubation (P<0.05). Incubation of sole Peltiphyllum peltatum highlyhampered the fermentation rate. Production of iso-SCFA both for plain Peltiphyllum and its mixturewere comparatively low. Supplementation of Peltiphyllum increased significantly soluble proteinconcentration during 12 h incubation (P<0.05). Peltiphyllum also had a very low C2+C4/C3 ratiocompared to other treatments. It could be concluded that Moringa oleifera is a potential alternativesupplement to replace either partially or completely concentrate as a conventional supplement, andPeltiphyllum peltatum supplementation could reduce excessive protein degradation and fermentation ofthe concentrate in the rumen.