Hay-based Diet Research Articles

Omega-3 Long-Chain Fatty Acids in the Heart, Kidney, Liver and Plasma Metabolite Profiles of Australian Prime Lambs Supplemented with Pelleted Canola and Flaxseed Oils.

The objective of the study was to ascertain whether human health beneficial omega–3 long-chain (≥C20) polyunsaturated fatty acid (n-3 LC-PUFA) content in heart, kidney and liver can be enhanced by supplementing prime lambs with graded levels of canola and flaxseed oil. Health status of the lambs, as a consequence of the supplementation, was also investigated by examining their plasma metabolites. Sixty purebred and first-cross lambs were allocated to one of five treatments of lucerne hay basal diet supplemented with isocaloric and isonitrogenous wheat-based pellets without oil inclusion (Control) or graded levels of canola oil at 2.5% (2.5C), 5% (5C), flaxseed oil at 2.5% (2.5F) and 5% (5F) in a completely randomised design. Pre-slaughter blood, post-slaughter kidney, liver and heart samples were analysed for plasma metabolite and fatty acid profiles. Summations of docosapentaenoic acid and docosahexaenoic acid, and total n-3 LC-PUFA were enhanced in the liver and kidney of 5F supplemented lambs with a marked decrease in n-6/n-3 ratio and significant breed differences detected. There were generally no deleterious impacts on animal health status. A combination of 5% oil supplementation and lamb genetics is an effective and strategic management tool for enhancing n-3 LC-PUFA contents of heart, kidney and liver without compromising lamb health.

Ground Juniperus pinchotii and urea in supplements fed to Rambouillet ewe lambs: I. Feedlot growth traits, blood serum parameters, and fecal characteristics.

Ground woody products and urea are low-cost roughage and N sources. Rambouillet ewe lambs ( = 48, 6 lambs/treatment; initial BW = 42 kg ± 3.8) were used to evaluate effects of using ground (juniper) and urea in supplements on feedlot lamb growth traits, blood serum parameters, and fecal characteristics. In a randomized complete block design (40 d), lambs were individually fed an ad libitum basal sorghum-Sudangrass hay diet, which was fed separate from 1 of 8 supplemental diets (6 lambs/diet; 533 g of supplement/d, as-fed basis). Treatment structure was a 4 × 2 factorial: 4 concentrations of ground juniper (JN: 15%, 30%, 45%, or 60% of DM) and 2 concentrations of urea (UR: 1 or 3% of DM). Lamb growth traits were evaluated on d 0, 5, 12, 19, 26, 33, and 40; blood serum was evaluated on d 6 to 8, 20 to 22, and 34 (at h 3 and 6), and feces was evaluated on d 35. Compared to lambs fed all of the other treatments, lambs fed JN60UR1 or JN60UR3 had reduced supplement DMI (negative quadratic, = 0.007). Hay and total DMI were variable across day (JN × UR × day, < 0.04), but no linear or quadratic trends were detected ( > 0.10). A JN × day interaction was detected ( < 0.001) for lamb BW and the JN × day negative quadratic trend ( = 0.02) for BW was influenced by reduced ADG (linear decrease, < 0.001) of lambs fed JN60. Lambs supplemented with UR3 vs. UR1 tended ( = 0.06) to have reduced BW but had similar ( > 0.17) ADG and G:F. Lamb G:F fluctuated across day (JN × day, = 0.007), but the JN × day quadratic trend ( < 0.001) was mainly due to reduced G:F in lambs fed JN45 or JN60 diets. As the percentage of JN increased in the supplement, serum IGF-1 linearly decreased ( = 0.04), and serum urea N quadratically increased ( < 0.001). The UR × hour interaction ( < 0.001) for serum urea N resulted from a greater decline from 3 to 6 h after feeding in lambs supplemented with UR1 vs. UR3. Increasing JN concentration tended to quadratically increase ( = 0.09) fecal DM and linearly decrease ( = 0.002) fecal N, but an effect due to dietary UR was not detected ( > 0.34). Results indicated that daily supplement DMI was restricted only by using JN60. However, a 60% JN-based supplement will not make an effective rangeland supplement for growing ewe lambs, and using 3% UR should not be considered, especially since daily UR intake was not restricted enough to be considered safe.

534 Effect of Acacia karroo leaf meal inclusion level on carcass characteristics, physico-chemical and sensory attributes and histological parameters of pedi goats fed on a Setaria verticillata grass hay-based diet

534 Effect of Acacia karroo leaf meal inclusion level on carcass characteristics, physico-chemical and sensory attributes and histological parameters of pedi goats fed on a Setaria verticillata grass hay-based diet

Plant Community Chemical Composition Influences Trembling Aspen (Populus tremuloides) Intake by Sheep.

Nutrients and plant secondary compounds in aspen (Populus tremuloides) may interact with nutrients in the surrounding vegetation to influence aspen use by herbivores. Thus, this study aimed to determine aspen intake and preference by sheep in response to supplementary nutrients or plant secondary compounds (PSC) present in aspen trees. Thirty-two lambs were randomly assigned to one of four molasses-based supplementary feeds to a basal diet of tall fescue hay (N=8) during three experiments. The supplements were as follows: (1) high-protein (60% canola meal), (2) a PSC (6% quebracho tannins), (3) 25% aspen bark, and (4) control (100% molasses). Supplements were fed from 0700 to 0900, then lambs were fed fresh aspen leaves collected from stands containing high (Experiment 1, 2) or low (Experiment 3) concentrations of phenolic glycosides (PG). In Experiment 2, lambs were simultaneously offered aspen, a forb (Lathyrus pauciflorus), and a grass (Bromus inermis) collected from the aspen understory. Animals supplemented with high protein or tannins showed greater intake of aspen leaves than animals supplemented with bark or the control diet (P<0.05), likely because some condensed tannins have a positive effect on protein nutrition and protein aids in PSC detoxification. Overall, animals supplemented with bark showed the lowest aspen intake, suggesting PSC in bark and aspen leaves had additive inhibitory effects on intake. In summary, these results suggest that not only the concentration but also the types and proportions of nutrients and chemical defenses available in the plant community influence aspen use by herbivores.

Utilization of concentrate supplements containing varying levels of cassava leaf pellet by growing goats fed a basal diet of pangola hay

The objective of this study was to evaluate the effect of varying levels of cassava leaf pellet (CLP) on feed intake, digestibility and rumen fermentation of goats fed with pangola hay as roughages. Eight growing crossed (Thai native x Anglo-Nubian) goats between 10 to 12 months of age and pre-trial average body weight of 18.5 + 2.5 kg were allotted into two groups on the basis of body weight in a randomized double 4 x 4 Latin square design to investigate the utilization of concentrate mixtures of varying levels of CLP. The four concentrate mixtures had CLP included at 0% (control), 10 % (CLP1), 20% (CLP2) and 30% (CLP3) in concentrate as replacing soybean meal (SBM) with CLP as 25 %CP, 50%CP and 75%CP, respectively. On average, all parameters measured, including dry matter intake (DMI), nutrients digestibility, ruminal ammonia-N (NH3-N), ruminal total volatile fatty acid (total VFA), individual VFAs concentration (mM/L), microbial N supply, and N retention increased (P less than 0.05) with the addition of CLP in concentrate up to 20% (CLP2) in concentrate, thereafter decreased (P less than 0.05) in goats fed CLP 30% (CLP3). The results indicated that replacing SBM with CLP as 50 %CP (CLP2), resulted in higher animal performance as a consequence of improved ruminal fermentation, microbial yield and N balance, but decreased (P less than 0.05) with 30% CLP diet. It is concluded that cassava leaf pellet can successfully replace soybean meal 50% CP as a protein source in growing goats.

English

A study was conducted to evaluate the effects of supplementation of a leaf based concentrate consisting of a 1:1 leaf mixture of Vernonia amygdalina and Tithonia diversifolia (VATD) as a direct replacement for brewers dried grains (BDG) on feed intake, growth performance and digestibility by West African Dwarf (WAD) goats on a basal diet of Panicum maximum hay. Twenty five growing WAD goats weighing between 8.07 - 9.60 kg were allotted into five dietary treatment groups in a completely randomized design with five goats per treatment. The mixed leaf meal (VATD) were included in the diets at 0% (T1), 5% (T2), 10% (T3), 15% (T5), and 20% (T5) of the total diet. The experiment lasted for twelve weeks. Results showed that dry matter (DM) intake (g/kg W0.75/day) was lowest (P<0.05) in control diet T1 (72.02), and higher in T3 (92.78) than T2, T4 and T5 (88.69, 86.61 and 86.70, respectively). Crude protein (CP) intake (g/kg W0.75/day) peaked at T3 and progressively reduced thereafter in T4 (15.10), T5 (14.83) and T2 (14.16). CP intake was higher (P<0.05) in T3 than T1. Daily weight gain (g/day) of goats ranged from 32.97 (T4 and T5) to 38.40 (T3). Crude protein digestibility was higher (P<0.05) in T5 (89.49%) than T1 (84.23%) and T4 (84.19%) but similar in T2 (85.47%) and T3 (86.10%). Better nitrogen intake (15.10 g/day) was observed in goats fed T4 compared to those fed T1 (14.32) and T2 (14.16). Rumen pH values were higher in T1 than T2, T3, T4 and T5. Ammonia N content (mg/100ml) of the rumen was similar in goats fed T2 (9.92), T3 (10.07) and T5 (9.80) but higher (P<0.05) than those fed T1 (8.19). The result suggests that WAD goats fed VATD leaf meal based concentrates perform better on diets with levels of mixed concentrates not exceeding 10%. Key words: Growth, Leaf meal, nitrogen utilization, Tithonia diversifolia, Vernonia amygdalina, WAD goats.

Effect of tanniniferous Acacia karroo leaf meal inclusion level on feed intake, digestibility and live weight gain of goats fed a Setaria verticillata grass hay-based diet

ABSTRACTThis study aimed to investigate the effects of tanniniferous Acacia karroo leaf meal inclusion level on performance of goats fed on a Setaria verticillata grass hay-based diet. Twenty indigenous male Pedi goats with an average initial live weight of 17.44 ± 2 kg were allocated, in a completely randomized design, to five dietary treatments containing Acacia karroo leaf meal inclusion levels of 20%, 25%, 30%, 40% and 50% of the total diet. Daily dry matter intakes were similar (P > .05) across the treatments. Acacia karroo leaf meal inclusion improved (P < .05) dry matter, organic matter, crude protein, neutral detergent fibre and acid detergent fibre digestibility coefficients. Dietary treatments had no effect on final live weights of goats. However, live weight gains were higher (P < .05) in goats fed a diet containing 50% Acacia karroo leaf meal inclusion level. Dry matter, crude protein and neutral detergent fibre digestibility coefficients were optimized at Acacia karroo leaf meal inclusion levels of 69.4%, 48.3% and 42.7%, respectively. Acacia karroo leaf meal inclusion improved nutrient digestibility and live weight gain of the goats and thus has potential to be utilized as a protein supplement when low-quality roughage is used as a basal diet.

Effects of early experience and alternative feeds on medusahead (Taeniatherum caput-medusae ssp. asperum) intake by sheep

The goals of this study were to test the effects of early experience at grazing medusahead – an invasive unpalatable weed – and the availability of forage alternatives on intake of medusahead later in life by sheep. The study involved two experiments of 10 days each. During Experiment 1, 29 yearling sheep were penned individually in a 2×2 factorial design with early experience at grazing medusahead (yes [n=15], no [n=14]) and alfalfa hay availability (yes, no) as the main factors. All animals were fed ad libitum amounts of freshly harvested medusahead daily from 10:00 to 13:00h; additionally, eight experienced and seven inexperienced sheep received alfalfa hay (0.31% body weight) at the same time. All groups had a basal diet of tall fescue hay. Intake of the forages, NaCl and trace-mineralized salt blocks was measured. In Experiment 2, sheep were then clustered into nine groups of three yearlings each (n=5 early experience; n=4 experience gained during Experiment 1) and one group of two yearlings (experience gained during Experiment 1) and grazed 10 plots of medusahead-infested rangeland. Grazing events were recorded daily at 5min intervals from 08:30 to 11:00h and from 16:00 to 17:00h, and the defoliation proportion of medusahead tillers was determined every five days. During Experiment 1, medusahead intake was not affected by early experience or alfalfa availability (P>0.05) but medusahead intake across days was cyclic with more pronounced intake peaks at the beginning and end of the experiment for inexperienced animals (P<0.05). Experienced sheep showed a greater gain-to-feed ratio (P<0.05), and tended to have greater average daily body weight gains and salt intake (P<0.10) than inexperienced sheep. Sheep fed alfalfa tended to eat less trace-mineralized salt blocks than sheep that did not receive this forage (P<0.10). During Experiment 2, the proportion of grazing events recorded on medusahead by both groups (yes/no early experience) of animals was almost nil, although experienced animals tended to defoliate more medusahead tillers than inexperienced animals (P=0.10). In conclusion, when sheep were fed ad libitum amounts of medusahead, intake was low and cyclic with a more even consumption of the weed by experienced animals. Under these conditions, early experience also favored animal performance. However, it is likely that such high exposure to medusahead attenuated the subsequent use of the weed during grazing.

Comparison of wet brewers' grains or dried distillers' grains as supplements to conserved bermudagrass forage as winter feeding options for beef cows

The objective of this study was to examine the use of 2 byproduct supplements and conserved warm-season forage as winter feeding options for primiparous beef cows. Gestating Angus ( = 48) and Brangus ( = 24) 2-yr-old cows were stratified by BW and breed to 1 of 12 pens. Pens were randomly assigned 1 of 2 supplements, wet brewers' grains (WBG) or dried distillers' grains (DDG). Coastal bermudagrass hay or round bale silage (RBS) was fed free choice (6 pens each) and cows received WBG or DDG supplements at a daily rate of 0.05% BW (DM basis) prorated for feeding 3 d/wk. Total BW and BCS changes did not differ ( = 0.65 and = 0.93, respectively) between DDG- and WBG-supplemented cows. Total amount of forage DM offered and mean calculated daily forage DM offered did not differ ( = 0.59 and = 0.20, respectively) between supplement treatments. Estimated daily mean and total supplement DM offered was greater ( < 0.001) for WBG than for DDG treatments. The same 2 supplements and forage sources were used in an unbalanced 6 × 4 design to measure intake, digestibility, and rumen parameters in ruminally fistulated steers. Supplement did not affect forage DMI of hay ( = 0.31) or RBS ( = 0.63). Total DMI was not different ( = 0.37 and = 0.73) for hay-based and RBS-based diets, respectively. Total tract digestibility tended to be greater ( = 0.06) for DDG than for WBG in hay diets but was not different ( = 0.76) for RBS diets. Daily mean ruminal pH was greater ( = 0.03) for WBG than for DDG when supplemented to hay-based diets. In RBS diets, a supplement × hour interaction ( = 0.05) existed for ruminal pH. Daily mean ruminal ammonia N concentration was greater ( < 0.001) for WBG-supplemented diets compared with DDG-supplemented diets. A supplement × hour interaction existed for ruminal ammonia in hay- ( < 0.001) and RBS- ( = 0.09) based diets. Ruminal pH and ammonia N concentrations stayed in ranges adequate to support ruminal metabolism and cattle performance. Marginal differences in ruminal measures between high-moisture and dry byproduct supplements resulted in no differences in cow performance when offered with hay or high-moisture forage. High-moisture forage sources can be coupled with high-moisture byproduct supplements.

Influence of pumpkin seed cake and extruded linseed on milk production and milk fatty acid profile in Alpine goats

The aim was to determine the effect of substituting pumpkin seed cake (PSC) or extruded linseed (ELS) for soya bean meal in goats’ diets on milk yield, milk composition and fatty acids profile of milk fat. In total, 28 dairy goats were divided into three groups. They were fed with concentrate mixtures containing soya bean meal (Control; n=9), ELS (n=10) or PSC (n=9) as main protein sources in the trial lasting 75 days. Addition of ELS or PSC did not influence milk yield and milk gross composition in contrast to fatty acid profile compared with Control. Supplementation of ELS resulted in greater branched-chain fatty acids (BCFA) and total n-3 fatty acids compared with Control and PSC (P<0.05). Total n-3 fatty acids were accompanied by increased α-linolenic acid (ALA, C18:3n-3; 0.56 g/100 g fatty acids) and EPA (C20:5n-3; 0.12 g/100 g fatty acids) proportions in milk of the ELS group. In contrast, ELS and PSC resulted in lower linoleic acid (LA, C18:2n-6; 2.10 and 2.28 g/100 g fatty acids, respectively) proportions compared with Control (2.80 g/100 g fatty acids; P<0.05). Abovementioned resulted in lower LA/ALA ratio (3.81 v. 7.44 or 6.92, respectively; P<0.05) with supplementation of ELS compared with Control or PSC. The PSC diet decreased total n-6 fatty acids compared with the Control (2.96 v. 3.54 g/100 g fatty acids, P<0.05). Oleic acid (c9-C18:1), CLA (c9,t11-18:2) and t10-,t11-C18:1 did not differ between treatments (P⩾0.08), although stearic acid (C18:0) increased in ELS diets compared with Control (12.7 v. 10.2 g/100 g fatty acids, P<0.05). Partially substituted soya bean meal with ELS in hay-based diets may increase beneficial n-3 fatty acids and BCFA accompanied by lowering LA/ALA ratio and increased C18:0. Pumpkin seed cake completely substituted soya bean meal in the diet of dairy goats without any decrease in milk production or sharp changes in fatty acid profile that may have a commercial or a human health relevancy.

Effect of Feeding Leucaena leucocephala Leaves and Pods on Feed Intake, Digestibility, body Weight Change and Carcass Characteristic of Central-Highland Sheep Fed basal Diet Wheat bran and Natural Pasture Hay in tigray, Ethiopia

Feed intake, digestibility, body weight change, carcass characteristics and profitability of supplementing 20 yearling central-highland sheep (17±1.5 kg) fed basal diet of natural pasture hay (NPH) and wheat bran with dried Leucana leucocephala leaves (LLL) and pods (LLP) and their mixture were evaluated after 84 d of feeding trial followed by 7 d of fecal collection and carcass analyses. Treatment diets(partial DM basis) were: T1 (control) = 90g wheat bran +3 g salt; T2=90g wheat bran +3 g salt +207 g LLL; T3= 90g wheat bran +3 g salt +207 g LLP; T4= 90g wheat bran +3 g salt+103.5 g LLL +103.5 g LLP with NPH offered ad libitum for all treatments. Lambs were assigned to each treatment in RCBD. The crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) contents of LLL were 21.8, 20.2 and 9.9%/DM, respectively and that of LLP 18.9, 42.1 and 25.7%/DM, respectively. The total DM intake was highest for T2, T3 and T4 as compared to the control group. However, the total CP and digestible CP intakes were highest (P 0.05) in total NDF and ADF intakes among the treatments. Coefficient of DM digestibility (P<0.05) of T2, T3 and T4 was higher than that of T1. Dressing percentage (DP) calculated onthe basis of slaughter body weight (SBW) was higher (P<0.05) for T2 and T4 than T1. Rib eye muscle area (REMA) and hot carcass weight were higher (P<0.05) for T2 followed by T4 and T3 but T1 was least. Thus, T2 (LLL supplementation) gave better nutrient digestibility, feed conversion efficiency and carcass characteristics and is recommended. However, all leucaena meal supplemented animals performed better than the control, thus can be used as supplements.

Effect of Substituting Dried Mulberry (Morus alba) Leaves for Concentrate Mixture on Growth Performance and Carcass Characteristics in Lambs Fed a Natural Pasture Hay Based Diet

This study evaluated the effect of substituting dried mulberry (Morus alba) leaves for concentrate mixture (CM; wheat bran and noug/niger (Guizotia abyssinica) seed cake mixture in 2: 1 proportion) on performance and carcass characteristics of sheep fed a basal diet of natural pasture hay. Thirty local yearling male sheep with an initial body weight (BW) of 18.2±1.61 kg were assigned to treatments in a completely randomized block design. Treatments were iso-nitrogenous supplements of 100% CM offered at 250 g DM/sheep/d (T1), 67% CM and 33% dried mulberry leaves (ML: T2), 33% CM and 67% ML (T3), 100% ML (T4) and 100% dried Leucaena leucocephala (LL) leaves (T5). The feeding and digestibility trials lasted for 90 and 7 days, respectively. Carcass of each experimental animal was evaluated at the end of the digestibility trial. The highest (P<0.05) DM intake was observed in treatment T4 (868.8±60.7) while the lowest intake was found in T1 (756.4±84.2) and T5 (763.5±115.6). The digestibility of nutrients (DM, OM, CP, NDF and ADF), average daily gain and carcass characteristics were similar in different treatments. Therefore, mulberry leaves could serve as a complete alternative replacement for wheat bran and niger-seed cake based conventional concentrate mixtures in lambs under Ethiopian smallholder farming conditions.

Effect of Biochar Type and Size on&amp;lt;i&amp;gt; in Vitro &amp;lt;/i&amp;gt;Rumen Fermentation of Orchard Grass Hay

Biochar, a byproduct from the biofuels industry, may be a potential feed additive in ruminant diets due to possible improvements in microbial fermentation. Therefore, the objective of this study was to determine the nutritive value, in vitro digestibility, volatile fatty acid (VFA) production, and gas production of biochar inclusion to an orchard grass (Dactylis glomerata) basal diet. The study was designed as a 3 × 2 factorial arrangement with 3 different biochar sources and 2 biochar processed sizes as the main effects factors. Experimental treatments were biochar from 3 different tree types: 1) Chestnut Oak (Quercus prinus L.; CO), 2) Yellow Poplar (Liriodendron tulipifera; YP), or 3) White Pine (Pinus strobus L.; WP), and processed at 2 different biochar particle sizes: a) 178 μm (Coarse). Biochar was added to the basal diet of orchard grass hay (872.35 g/kg of DM, 98.31 g/kg of CP, and 704.02 g/kg of aNDF, DM basis) at a rate of 81 g/kg DM. Biochar residual ash content was greater (P P P = 0.01) with lower aNDF content in both WP sizes compared with their respective biochar type and size. Gas production was not influenced (P = 0.23) by biochar tree type; however, gas production was increased (P = 0.05) by Fine particle size compared with Coarse biochar. The in vitro true digestibility (IVTD) of orchard grass hay was increased (P = 0.01) by the inclusion of Fine biochar particle size compared with Coarse particle size. Additionally, in vitro CP true digestibility (DCP) exhibited a type × size interaction (P = 0.01). Crude protein digestibility was lower for Fine particle-sized CO and WP biochar sources compared with Coarse particle-sized CO and WP (P ≤ 0.004). However, DCP was not different between Coarse and Fine particle-sized YP biochar (P = 0.70). Volatile fatty acids (acetate, propionate, and butyrate) were not altered by biochar type (P ≥ 0.66) or particle size (P ≥ 0.19). These results indicate that both tree type and particle size of biochar may need to be carefully considered before incorporating into a ruminant diet. Furthermore, Fine particle-sized biochar may be the most effective to incorporate as a feed additive in a ruminant diet based on digestibility parameters.

Blood profiles of indigenous Pedi goats fed varying levels of &lt;i&gt;Vachellia karroo&lt;/i&gt; leaf meal in &lt;i&gt;Setaria verticillata&lt;/i&gt; hay-based diet

Vachellia karroo ( Acacia karroo ) is promising fodder for goats in the critical dry season in communal rangelands. The only limitation to the use of this fodder tree is the presence of phenolic compounds, such as condensed tannins. A study was conducted to investigate the effects of tanniniferous V. karroo leaf meal feeding on blood profiles of indigenous Pedi goats fed a basal diet of Setaria verticillata grass hay. Twenty indigenous Pedi goats, weighing 18 ± 2 kg, were allocated in a completely randomized design to five dietary treatments containing V. karroo leaf meal at 20% (S 80 A 20 ), 25% (S 75 A 25 ), 30% (S 70 A 30 ), 40% (S 60 A 40 ) and 50% (S 50 A 50 ) of the total diet in a 22-day trial. Twelve ml of blood were collected from the jugular vein from each goat before and after the experiment for haematological and serum biochemical assays. Daily dry matter intake (DMI) was similar across treatments, ranging from 633 g to 765 g per goat per day. There was no difference in initial and final bodyweights of goats consuming various experimental diets. However, bodyweight gains were significantly higher in goats fed a diet with 50% leaf meal as compared with other treatment groups. There were no differences in haematological indices of Pedi goats except for mean corpuscular haemoglobin (Hb) concentration. Goats fed 50% leaf meal had significantly lower mean corpuscular haemoglobin concentration (MCHC) values as compared with other treatment groups. Similarly, there were no differences in the blood serum chemistry of goats that consumed various inclusion levels of V. karroo , except for serum total protein (TP) and alanine aminotransferase (ALT). Goats fed 50% leaf meal had depressed serum TP, while serum enzyme Alanine aminotransferase (ALT) concentration decreased significantly in goats fed 25% leaf meal as compared with those on the 20% dietary treatment. Tannin concentration of 8.2 g/kg dry matter (DM) had no toxic effect on experimental animals. A 40 % inclusion of V. karroo in a Setaria verticillata hay-based diet may be fed to indigenous Pedi goats without compromising the immunity system and health of the animals. Keywords: Condensed tannin, fodder, haematology, serum

Effect of fibrous diets on chemical composition and odours from pig slurry.

ObjectiveIncorporating high fibre ingredients into pig diets has the potential to reduce odour emissions from of pigs. The current study was carried out to determine effect of diets containing 0, 80 and 160 g/kg of each of lucerne hay, maize cobs and sunflower husks on the chemical characteristics and odours from pig slurries.MethodsTwenty eight pigs averaging 18±2.0 kg were kept in individual cages, over four weeks. All pigs were fed ad libitum. Faeces and urine were collected, mixed in a 1:2.3 ratio (w/w), stored and fermented for 16 days in a temperature controlled room at 22°C±2.3°C. The slurry was sampled twice (on day 1 and on day 16) of the fermentation period and analysed for pH, chemical oxygen demand (COD), nitrogen and short chain fatty acids (SCFA) concentration, on wet basis. All samples were tested for odour offensiveness using 18 panelists. A scale of 1 to 5 was used to rank the odour severity, (1 = not offensive, 5 = extremely offensive).ResultsSlurry pH and COD varied with fibre source (p<0.05). On day 16, COD for lucerne hay, sunflower husk and maize cobs were 369, 512, and 425 (standard error of the mean = 34.2) mg of oxygen per litre. Total SCFA concentration was higher at day 16 than day 1 (p< 0.05). Odour offensiveness varied with fibre source across both incubation periods (p<0.05). Sunflower husks and lucerne hay-based diets were rated as less offensive (mean rank = 2.2) than maize cob diets (mean rank of 4.3) (p<0.05).ConclusionIt was concluded that different fibre sources and incubation period influence chemical composition and odour of the slurry. There is, thereby, a need to incorporate locally available fibrous feeds in the diet of pigs because they have an economical and environmental relevance to pig management.

Impact of dynamics of faecal concentrations of plant and synthetic n-alkanes on their suitability for the estimation of dry matter intake and apparent digestibility in horses

SUMMARYIn horses, the quantity of faeces and the faecal concentrations of plant and synthetic alkanes are inconsistent throughout the day. The estimation of feed intake and digestibility can additionally be limited by irregular and incomplete faecal recovery of alkanes that are used as dietary markers. The correction of alkane concentrations minimizes the bias of estimates, but requires the determination of faeces quantity by total collection. However, in consideration of the dynamics of alkane concentrations in faeces, sampling at selected timeframes throughout a day may be useful in avoiding such correction. Five adult horses were fed a hay-based diet offered three times a day in equal amounts. Horses received a bolus with similar quantities of n-octacosane (C28), n-dotriacontane (C32) and n-hexatriacontane (C36) synthetic alkanes twice a day. Total faeces were quantified over 3 consecutive days. Dry matter intake (DMI), output (DMO) and digestibility (DMD) were determined from the total collection trial and additionally estimated for each of 12 equal timeframes throughout the day. The diurnal patterns of the single faeces quantity (SFQ) and faecal alkane concentrations were similar between horses and were repeated from day to day. The intra-day dynamic of SFQ was pronounced. The dynamic of the faecal concentration was much more pronounced when the alkane was administered twice instead of three times a day. The faecal recovery of alkanes that has been calculated from the total collection trial ranged from 82 ± 4·1% for C36 to 108 ± 11·1% for C28. Measured DMI was 12·0 kg/day, measured DMO was 5·9 kg/day and measured DMD was 0·51. Reliable estimates were obtained for DMI with 12·3 ± 0·79 kg/day for the combination of n-nonacosane (C29) and C28 and 12·1 ± 1·01 kg/day for the combination of n-tritriacontane (C33) and C28 at 2 h after administration, and 12·1 ± 0·96 kg/day for the combination of n-hentriacontane (C31) and C32 at 2 h prior to the morning meal, which included the first bolus administration. When calculated from DMO and DMD, DMI was 12·2 ± 0·89 kg/day for C29 and 12 ± 1·0 kg/day for C33 between 5 and 6 h after the morning meal. Estimates of DMD were unbiased between the 3rd and 4th hour after the morning meal with 0·52 ± 0·014 for C29 and 0·51 ± 0·021 for C33, respectively. The DMO was 5·7 ± 0·34 kg/day and 6·1 ± 0·43 kg/day when estimated 3–4 h after the 2nd meal, or prior to the 2nd bolus administration, using the product of SFQ and the daily defecation frequency or the synthetic alkanes, respectively. Knowledge of defecation dynamics might be helpful for simplifying experimental trials. They specifically followed intake dynamics, which can prospectively be used to select sampling timeframes. Based upon current results, a selection of two to three spot samples of faeces that are evenly distributed between 2 h before and 6 h after the morning meal, which was the time of bolus administration, allows for the greatest reliability. Defecation dynamics are probably less influenced by ration/bolus type, rate of exercise, or gut peristalsis, which nevertheless can result in individual shifts of optimal timeframes.

A meta-analysis and meta-regression of the impact of particle size, level, source and preservation method of forages on chewing behavior and ruminal fermentation in dairy cows

A meta-analysis of the impact of forage particle size (FPS) on chewing activity, rumen pH and volatile fatty acids (VFA) in dairy cattle was conducted following a search of the literature. A meta-regression was conducted to test the additional effect of forage level, source and preservation method on the heterogeneity of the results of FPS on the same target variables. A total of 42 papers and 86 trials with the change of FPS in the diet of dairy cattle were identified. Decreasing of FPS in the diet from an average of 10.0±4.9–6.7±4.11mm lowered eating (P<0.01), rumination (P<0.01), and total chewing time (P<0.01) by 19, 28, and 44min/d, respectively. A similar effect and heterogeneity were observed for all these variables when expressed as min per kg of DMI. Meta-regression analysis revealed forage level as an important source for this heterogeneity. Accordingly, this analysis indicated that eating time (P=0.04) and total chewing time (P<0.01) per kg of DMI decreased with lowering FPS in high level of dietary forage inclusion (>500g/kg forage). Forage preservation method was another source of variation accounting for high heterogeneity in the results of FPS in which eating (P=0.03), rumination (P=0.01), and total chewing (P=0.02) activity decreased only in silage-based diets but not in hay-based diets. Total VFA concentration (P<0.01) and butyrate proportion (P=0.03) increased by 25 and 9%, respectively, with decreasing of FPS. Forage level also was an important source of the variability in which rumen pH dropped (P<0.01) with decreasing of FPS only in low level of forage feeding. In contrast, VFA concentration (P=0.02) and propionate proportion (P<0.01) increased with decreasing FPS in high level of forage inclusion. As result, the A:P ratio lowered (P=0.04) with decreasing of FPS in high level of forage feeding. Moreover, rumen pH decreased (P<0.01) with decreasing of FPS in silage-based diet, but acetate proportion increased (P<0.01) with decreasing FPS in hay-based diet, resulting in greater (P<0.01) A:P ratio with decreasing FPS in hay-based diet. In conclusion, the study confirms enhancing effects of feeding long FPS on chewing activity and ruminal fermentation; however, these effects were strongly modulated by forage level and preservation method of forages, with decreasing FPS being more influential in high level of forage inclusion and in hay-based diets.

Influence of the calf presence during milking on dairy performance, milk fatty acid composition, lipolysis and cheese composition in Salers cows during winter and grazing seasons.

The milking of Salers cows requires the presence of the calf. The removal of the calf would simplify the milking routine, but it could also modify the milk yield and the milk and cheese composition. Therefore, the aim of this experiment was to evaluate the effect of calf presence during milking during sampling period (winter or grazing periods), on dairy performance, milk fatty acid (FA) composition, lipolysis and cheese yield and composition. Nine and 8 Salers lactating cows were milked in the presence (CP) or absence (CA) of their calves respectively. During winter, the cows were fed a hay-based diet and then they only grazed a grassland pasture. Calf presence during milking increased milk yield and milk 16:0 concentration and decreased milk fat content and milk total odd- and branched-chain FA (OBCFA) concentrations. Calf presence only increased initial lipolysis in milk collected during the winter season. Milk from CP cows compared to CA cows resulted in a lower cheese yield and ripened cheeses with lower fat content. Milk from the grazing season had lower saturated medium-chain FA and OBCFA concentrations and higher 18:0, cis-9-18:1, trans-11-18:1 and cis-9, trans-11-CLA concentrations than that from the winter season. Initial milk lipolysis was higher in the winter than in the grazing season. These variations could be due to seasonal changes in the basal diet. Furthermore, the effect of calf presence during milking on milk fat composition was lower than that on dairy performance, cheese yield and composition. Removing the calf during the milking of Salers cows seems feasible without a decrease in milked milk, and with a positive effect on cheese yield and fat content, under the condition that we are able to select cows having the capacity to be milked easily without the calf.

Amino acid utilization of lactating dairy cows when diets are changed from an alfalfa-based diet to cereal straw-based diets

This experiment assessed the utilization of amino acids (AA) by the mammary gland of cows when diets are changed from an alfalfa hay-based diet (AH) to cereal straw-based diets using corn stover (CS) or rice straw (RS). Thirty multiparous Holstein dairy cows were selected and randomly assigned to 1 of 3 treatments (n=10). After 13 weeks’ feeding, arterial and venous plasma were collected every 6h over 2days and AA concentrations measured. The cows fed the CS or RS diet had lower milk and protein yield despite similar dry matter intake. The digestive AA flow was predicted to be lower in the cows fed CS or RS than in AH-fed cows. The arterial concentration of methionine and valine was lower in the cows fed RS than in cows fed AH. The mammary uptake of most essential AA, especially branched-chain AA, methionine, and arginine, was greater in the AH-fed cows than in cows fed CS or RS. The ratio of mammary uptake to milk output of methionine was lower in the RS-fed cows than that in the cows fed AH, with a value below 1 for both. In summary, the insufficient supply of free AA from arterial plasma presented to the mammary gland and lower mammary plasma flow restrict the mammary AA uptake for milk protein synthesis when energy is limited. On the other hand, the utilization of leucine and methionine may be a limiting factor for milk protein synthesis and lactation performance when corn stover or rice straw is fed to dairy cows.

Effects of flaxseed and chia seed on ruminal fermentation, nutrient digestibility, and long-chain fatty acid flow in a dual-flow continuous culture system.

Flaxseed (FS) and chia seed (CS) are oilseeds rich in omega-3 fatty acids, which may change meat and milk composition when added to ruminants' diets and may have health benefits for humans. Literature on the effects of CS supplementation on ruminal metabolism is nonexistent. A dual-flow continuous culture fermenter system consisting of 6 fermenters was used to assess the effect of FS and CS supplementation in an alfalfa hay-based diet on ruminal fermentation, nutrient digestibility, microbial protein synthesis, and long-chain fatty acid flow. Diets were randomly assigned to fermenters in a replicated 3 × 3 Latin square design, with 3 consecutive periods of 10 d each, consisting of 7 d for diet adaptation and 3 d for sample collection. Each fermenter was fed a total of 72 g of DM/d divided in 6 equal portions. Treatments were 1) alfalfa hay + calcium soaps of palm oil fatty acid (MEG; 69.3 g DM/d of alfalfa hay plus 2.7 g DM/d of calcium soaps of palm oil fatty acid), 2) alfalfa hay + FS (FLAX; 68.4 g DM/d of alfalfa hay plus 3.6 g DM/d of ground FS), and 3) alfalfa hay + CS (CHIA; 68.04 g DM/d of alfalfa hay plus 3.96 g DM/d of ground CS). Dietary treatments had similar amounts of total fat, and fat supplements were ground to 2-mm diameter. Effluents from the last 3 d of incubation were composited for analyses. Data were analyzed using the MIXED procedure of SAS. Ruminal apparent and true nutrient digestibility of all nutrients did not differ ( > 0.05) among treatments. Compared with MEG, FLAX and CHIA increased the flows of C18:3 -3, C20:4 -6, and total PUFA ( < 0.01). Both CHIA and FLAX treatments had greater ruminal concentrations of C18:0, indicating that both CS and FS fatty acids were extensively biohydrogenated in the rumen. The NH-N concentration, microbial N flow, and efficiency of microbial protein synthesis were not affected ( > 0.05) by treatments. Lastly, there were no differences ( > 0.05) among diets for total VFA concentration and molar proportions of individual VFA. Results from this study indicate that FS and CS supplementation did not impair ruminal fermentation, digestibility, microbial efficiency, and ruminal N metabolism. Overall, CS appears to be as effective as FS as a fat source when added to ruminants' diets using a dual-flow continuous culture system.