Hay-based Diet Research Articles

Effects of two tannin extracts at different doses in interaction with a green or dry forage substrate on in vitro rumen fermentation and biohydrogenation

Extensive ruminant farming systems often face fluctuating pasture availability, resulting in two periods with very different forage quality. Tannins are natural bioactive compounds able to modify ruminants’ digestive metabolism thanks to their bioactive properties. To evaluate a differential effect of tannins in different feeding situations, according to the availability of pasture along the year, an in vitro rumen incubation trial was performed. Buffered sheep rumen content was incubated in vitro with two different substrates, vetch pasture (VP) and vetch hay (VH), in the presence of two different tannin extracts, from quebracho (QUE) and a mixture of quebracho and chestnut tannins (MIX). Each of the tannin extract was tested at 0, 15 and 30 g of tannin/kg DM. The gas production was determined at 3.5 and 24 h of fermentation. After 24 h in anaerobic conditions, volatile fatty acids (VFA), ammonia and fatty acids (FA) were analysed. Interesting significative two-way interactions with different tannin extracts were observed in some fermentation parameters. Adding MIX to VH treatment resulted in a higher depression (P < 0.050) of ammonia production and iso-VFA proportions, compared to QUE supplementation, while no differences were observed in VP treatment. QUE was more effective than MIX (P < 0.050) in reducing acetate/propionate ratio when supplemented to VH treatment. However, the MIX treatment showed a higher increase (P < 0.050) of CO2/CH4 ratio after 24 h of incubation when supplemented at 30 g/kg, compared to QUE treatment. MIX and QUE exerted similar effects on rumen biohydrogenation. Tannin extracts decreased the rumenic/linoleic acid ratio and iso-FA proportions (P < 0.050) only when added to the VH treatment. These results demonstrate that tannin extracts are more effective in modulating rumen metabolism when associated with a hay-based diet. Also, the MIX treatment was more effective in protecting proteins from ruminal degradation, a key point in grazing periods. Therefore, extensive husbandry could benefit from different strategies for using dietary tannin extracts according to season and pasture availability.

Feed intake, digestibility and growth performance of Dorper-Menz cross bred sheep fed local brewery by-product (atella) and concentrate mixture at different levels of combination

The aim of this experiment was to evaluate the effect of graded level of local brewery by-product (atella) replacement to concentrate mixture on feed intake; digestibility and body weight change of Dorper-Menz crossbred lambs fed hay basal diet. The feeding period of 90 days was preceded by 15 days of acclimatization period. The experimental design was Randomized Complete Block Design (RCBD) with five treatments: T1 [Control, hay ad libtium]; T2 [25% atella + 75% concentrate mix]; T3 [50% atella + 50% concentrate mix]; T4 [75% atella + 25% concentrate mix]; and T5 [100% atella]. Body weight changes were monitored fortnightly for 112 days. Data on feed intake, body weight change, and digestibility were subjected to Analysis of Variance (ANOVA) using the General Linear Model procedure. Partial budget analysis was performed to evaluate profitability of treatments. The crude protein content of atella was above 20% and can be used as a supplement. Atella alone or at different level with commercial concentrate mixture has significantly increased body weight gain of crossbred sheep. The positive weight gain results of atella supplemented group clearly indicate the potential of atella. Based on partial budget analysis, supplementation of dried atella could be recommended for fattening Dorper-Menz crossbred male lamb.

77 Evaluation of Models Used to Predict Dry Matter Intake in Forage-Based Diets

Abstract Data from experiments conducted at the University of Nebraska-Lincoln were pooled to compare predicted and observed dry matter intake (DMI) of growing cattle consuming foraged-based diets (corn silage, grass, alfalfa, or sorghum-hay) to determine the accuracy of current modeling systems. Experiments (n = 22) were a minimum of 84 days and included individually fed calves using the Calan gate system with 8 to 12 calves per treatment mean or pen-fed calves with 8 to 12 head per pen. Average body weight (BW) of calves ranged from 235 to 397 kg with average daily gain (ADG) between 0.16 and 1.65 kg. Cattle were fed ad libitum and mid-point BW and ADG were entered into the Beef Cattle Nutrient Requirements Model (2016) to determine predicted DMI. Simple regression was used to compare predicted and observed DMI to determine the accuracy of the prediction model. Ninety-three treatment means were evaluated and were separated into three categories: hay-based diets (n = 24), hay-based diets with distillers grains (n = 31), and corn silage-based diets (n =38). The model for observed versus predicted DMI was significant (P &amp;lt; 0.05; R2 = 0.09) when comparing all means but had a poor R2. The model was the best at predicting DMI for forage-based diets (P &amp;lt; 0.08; R2 = 0.22). Observed and predicted DMI were regressed along TDN values, calculated using book values and digestion studies. As TDN increased, observed DMI increased linearly (P &amp;lt; 0.01) and predicted DMI had a quadratic response (P &amp;lt; 0.01), increasing up to 63% and then decreasing with increasing TDN. The model over predicted DMI intake for TDN &amp;lt; 63% and under predicted DMI in forage-based diets greater than 63% TDN. Further development of the current modeling system through addition of intake data from forage fed growing cattle is needed

Effect of feeding regime on growth performance of growing Yankasa rams fed basal diet of sorghum hay or silage supplemented with concentrate

Smallholder farmers in sub-Saharan Africa offer their stocks little or no supplementary feed but depend mostly on native pastures which are in low nutrient quality. The study was aimed at evaluating the effect of feeding regime on growth performance, nutrient metabolism, rumen indices and economics of production of Yankasa rams fed basal diets of grain sorghum hay or silage supplemented with concentrate. Sixteen growing Yankasa rams weighed 17.0±0.2 kg were randomly assigned to four feeding regime treatment: T1 = Sorghum hay + concentrate daily, T2 = Sorghum silage + concentrate daily, T3 = Sorghum silage +&#x0D; concentrate after 1-day and T4 = Sorghum silage + concentrate after 2-days. The&#x0D; parameters measured were hay intake, concentrate intake, total feed intake, daily feed intake, initial weight, final weight, weight gain, daily weight gain, feed conversion ratio (FCR), apparent nutrient digestibility, nitrogen balance and costs-benefit. The result showed that hay intake (25.28 – 29.23 kg), concentrate intake (6.19 – 19.41 kg), total feed intake (35.41 – 48.47 kg), daily weight gain (0.04 – 0.05 kg) and weight gain (2.85 – 3.35 kg) were significantly (P&lt;0.05) affected by the feeding regime with rams fed silage + concentrate daily recording higher values. Better FCR was obtained in rams fed silage + concentrate after 2-days. Dry matter (79.22%), crude protein (85.59%), NDF (75.30%) and ADF (78.02%) digestibility coefficients were higher (P&lt;0.05) for rams fed silage + concentrate after 1-day (every other day). The percentage of nitrogen absorbed and retained were higher (P&lt;0.05) in rams fed silage + concentrate after 1-day (85.62 and 82.72%, respectively). The cost per kg gain of N1046.40 for rams fed hay + concentrate daily was significantly (P &lt;0.05) lower than the cost per kg gain of other feeding regimes. It can be concluded that sorghum silage could be fed alongside concentrate daily for improved feed intake and weight gain, but for better cost-efficiency, it is recommended that farmers should feed hay and supplement concentrate daily to rams.&#x0D; &#x0D; &#x0D; Les petits exploitants agricoles d'Afrique subsaharienne offrent peu ou pas d'aliments supplémentaires à leurs stocks, mais dépendent principalement de pâturages indigènes de faible qualité nutritive. L'étude visait à évaluer l'effet du régime alimentaire sur la performance de croissance, le métabolisme des nutriments, les indices rumen et l'économie de la production de béliers Yankasa nourris à des régimes basaux de foin de sorgho de grain ou d'ensilage complétés par du concentré. Seize béliers Yankasa en croissance pesaient 17,0±0,2 kg ont été assignés au hasard à quatre traitements du régime alimentaire : T1 = foin de Sorgho + concentré tous les jours, T2 = ensilage de Sorgho + concentré tous les jours, T3 de Sorgho + concentré après 1 jour et T4 = ensilage de Sorgho + concentré après 2 jours. Les paramètres mesurés étaient l'apport en foin, l'apport en concentré, la consommation totale d'aliments pour animaux, l'apport quotidien en aliments pour animaux, le poids initial, le poids final, le gain de poids quotidien, le rapport de conversion des aliments pour animaux (FCR), la digestibilité apparente des éléments nutritifs, l'équilibre azoté et les coûts-avantages. Le résultat a montré que l'apport en foin (25.28 à 29.23 kg), l'apport en concentré (6.19 à 19.41 kg), la consommation totale d'aliments (35.41 à 48.47 kg), le gain de poids quotidien (0,04 à 0,05 kg) et le gain de poids (2.85 à 3.35 kg) ont été considérablement (P&lt;0.05) affectés par le régime d'alimentation avec des béliers nourris à l'ensilage + concentré enregistrant quotidiennement des valeurs plus élevées. Un meilleur FCR a été obtenu dans l'ensilage alimenté par bélier + concentré après 2 jours. Matière sèche (79.22 %), protéines brutes (85.59 %), NDF (75.30 %) et ADF (78.02%) les coefficients de digestibilité étaient plus élevés (P&lt;0.05) pour les béliers nourris à l'ensilage après 1 jour (tous les deux jours). Le pourcentage d'azote absorbé et retenu était plus élevé (P&lt;0.05) chez les béliers nourris à l'ensilage + concentré après 1 jour (85.62 et 82.72 %, respectivement). Le gain par kg de N1046.40 pour les béliers nourris quotidiennement au foin + concentré était significativement (P &lt;0.05) inférieur au coût par kg de gain des autres régimes alimentaires. On peut conclure que l'ensilage de sorgho pourrait être alimenté aux côtés du concentré quotidien pour améliorer l'apport alimentaire et le gain de poids, mais pour une meilleure rentabilité, il est recommandé que les agriculteurs nourrissent le foin et complètent le concentré quotidiennement aux béliers

Effects of Leucaena leucocephala supplementation to basal hay on Energy and Protein metabolism in West African. Dwarf sheep

Energy and protein utilization and quantitative retention of protein, fat and energy was investigated with twelve castrated West African Dwarf (WAD) sheep averaging (23.0 h 2.4 kg BW) in nitrogen and energy balance trials. Dried leaves of Leucaena leucocephala were offered as supplement at two levels 25% (diet 2) and 50% (diet 3) of dry matter intake (DM1), replacing hay in the basal hay diet. The basal hay diet without supplementation was the control. Measurements were performed by means of nitrogen and carbon balances and with the use of indirect calorimetry The digestibility and utilization of protein were influenced (P&lt;0.05) by supplementation. Metabolisability of energy (ME/ GE) was on the average 42.9 (SEM 4.3)% being significantly (P&lt;0.05) different among treatments. Diet 2 had a higher (P&lt;0.05) retained protein (9.6 g/d) compared with the control diet and hence a superior (P&lt;0.05) protein utilization than the control and diet 3, respectively. It was concluded that Leucaena leuccocephala improved protein utilization and retention in WAD sheep.

NITROGEN RETENTION IN RAPIDLY-GROWING STEERS GIVEN UREA SUPPLEMENTED DIETS

Four calves equipped with permanent rumen and T-piece duodenal caninulus were given four diets in a Latin square experiment carried out at two stages of development. DM flow was measured by dual-phase markers. The basal diet of hay and concentrate was calculated to be low In rumen degradable N (RDN) and. tissue N. Additional RDN was provided by ad­ding 6, 12 or 18g urea/kg concentrate. Supplementary urea did not affect OM digestion either in the stomach or In the entire digestive tract. At the older age OM digestion in the stomach and the entire tract was significantly higher. On the basal diet, N retention was low. The flow of microbial N measured by the DAPA technique was not affected by diet and it was calculated that between 3 and 7g "s/d were recycled to the rumen. The addition of supplementary urea increased N retention par­ticularly at the lowest level of supplementation due to a concomitant decrease In urinary N.

Evaluation of cassava foliage as a protein supplement for sheep

Three trials were conducted to evaluate the potential of cassava (Manihot esculenta) foliage (leaves and petioles) as a protein supplement for sheep. In the first trial, nylon bag degradability of cassava foliage was studied. Proximate analysis of cassava foliage was conducted before and after the incubation. Rumen Ammonia Concentration (RAC) and pH were determined at 0, 4 and 8 hours after feeding cassava foliage diet (30%). Proximate composition of sundried cassava foliage was (%) DM 91.25, CP 18.55, NDF, 31.41, ADF, 29.2, EE, 6.6, Ash, 12.95. Nylon-bag dry matter disappearance (DMD) increased significantly (P&lt;0.05) from 15.75% to 75.5% RAC values increased significantly from 8.20mg NH3/100ml at zero hour to 11.41mg NH3/100ml at 8 hours post feeding. Rumen fluid pH was not significantly changed by the 30% cassava foliage diet. In the second trial lasting 56 days, twenty-eight Yankasa/ WAD yearling rams of initial average weight of 18kg were balanced for weight and randomly allotted to seven treatments. All rams except those on control diet were fed cassava foliage or groundnut haulms or both at 1.0% or 1.5% of body weight (BW) as supplements to a basal diet of Gamba hay. Feeding Gamba hay alone (control) resulted in weight loss (-30.5g/day) but with cassava foliage or groundnut haulms supplementation at 1.0% BW, significantly higher gains of 39.2 and 44.6g/day were achieved respectively. At 1.5%BW level of supplementation with cassava foliage or groundnut haulms higher weight gains of 41.2 and 51.7g/day were achieved while feeding the (50.50) combined supplements at 1.0 and 1.50% BW resulted in live weight gains of 65.1 and 69.3g/day respectively. The third trial consisted of a four week grazing trial followed by a metabolic study. Twenty-one Yankasa/WAD yearling rams were randomly allotted to seven treatments and were balanced for live weight. All rams were allowed to graze standing digitaria hay as basal diet, except the rams on control diet. Those on treatment were fed cassava foliage or groundnut haulms or a (50:50) combination of both at 0.5% and 1.0% (BW). The metabolic study consisted of a seven day adjustment period and a seven day total collection period. There was no significant difference (P&gt;0.05) in the live weight gains of rams on the control diet compared with those supplemented except for those supplemented with cassava foliage and groundnut haulms combined at 1% level where the weight gain was significantly higher (P&lt;0.05). Feed intake was not significantly (P&gt;0.05) affected by feeding either supplement. Supplementing digitaria hay with cassava foliage at both 0.5% and 1.0% BW did not significantly increase the nitrogen retention values, but groundnut haulms supplemented at 1.0% BW significantly (P&lt;0.05) increased the nitrogen retention values.

Daniellia oliveri as a fodder tree for small ruminant and the interaction of its tannin with ruminal ammonia

Daniellia Oliveri was examined as a potential fodder for small ruminant, using nine castrated and ruminally fistulated West African Dwarf sheep (29 kg BW) to determine rumen ammonia and nutrient digestibility. Dried leaves of Daniellia oliveri were offered at two levels (25% and 50% of DMI) as supplement to a basal hay diet. A digestibility trial of 8 days was conducted after 10 days of adaptation period. Rumen liquor was sampled one hour before, and one, three and five hours after the morning feeding for three consecutive days. Diet D50% showed a higher (P&lt;0.05) pH than both the control and D25% diets, respectively. Diet D25% had an inferior (P&lt;0.05) pH than the controls. The ruminal ammonia concentration of D25% was superior (P&lt;0.05) to D50% and the controls, respectively. Similarly, diet D50% had a superior (P&lt;0.05) ruminal ammonia concentration than the controls. There were significant increases (P&lt;0.05) in the OM, CP, NDF, ADF, ADL and cellulose intake of D50% diet compared with the controls. Similarly, inclusion level of 50% Daniellia oliveri resulted in a reduction (P&lt;0.05) in digestibility of DMI, OM, NDF, ADF and ADL, in comparison to sheep fed the control diet. Cellulose and hemi-cellulose digestibility of diet D50% was superior (P&lt;0.05) to that of the controls. It would appear that condensed tannins had inhibitory effect on organic matter and detergent fibre digestibility. It was concluded that Daniellia oliveri with a high CP and GE (165 g/kg and 20.3 kJ/g DM) respectively, could serve as a fodder tree for small ruminant in spite of its relatively high content of condensed tannin (48 g/kg DM). An inclusion range of 25 to 50% was recommended during period of scarcity.

COMPARATIVE STUDY ON THE USE OF FOUR PROTEIN SUPPLEMENTS BY WEST AFRICAN DWARF (WAD) SHEEP.

Feedblocks, poultry manure diet, gliricidia: leucaena mixture (1:1 W/W) and maize offal diet were compared as sources of protein supplements for WAD sheep fed a basal diet of elephant grass hay (Pennisetum purpureum), through a 12-week performance and digestibility study. Dry matter and organic matter intakes (DMI, OMI) of the sheep were higher (P0.05) on the gliricidia: leucaena supplement than on the other diets. DMI on poultry manure and maize offal diets were not significant (P0.05). Organic matter intake (OMI) of the animals followed the same trend as DMI. Sheep fed legume supplements excelled in intakes of crude protein (CP), acid detergent fibre (ADF) and digestibilities of dry matter (DM), organic matter (OM) and neutral detergent fibre (NDF) (P&gt;0.05). Intakes of CP and ADF by sheep on the other supplements were not significantly different (P&gt;0.05). Sheep fed on feedblock supplement consumed the least amount. (P0.05) of NDF. Variations were observed in DM,OM, and NDF digestibilities by sheep on maize offal, poultry manure and legumes supplements. Crude protein digestibility in the legumes and feedblocks supplements was higher (P0.05) than with the other two supplements. All the sheep used gained weights but those on maize offa' diet recorded higher (P0.05). weight gain (86.57g) than those on browse leaves (59.40g), feedblocks (47.80g) and poultry manure (40.44g). Rumen pH was lower (P&lt;0.05) on the gliricidia: leucaena supplement than on other diets. Total VFA recorded for sheep on maize offal diet and legumes supplements was higher (P&lt;0.05) than for the other two supplements. Blood urea nitrogen of the supplements were not significantly different (P&gt;0.05)

Effects of 00-rapeseed meal inclusion in Parmigiano Reggiano hay-based ration on dairy cows’ production, reticular pH and fibre digestibility

Hay-based diets are typically used in Parmigiano Reggiano cheese production. Parmigiano Reggiano feeding regulation prohibits 00-rapeseed dietary inclusion. The objectives of this study were to investigate the effects of substituting soybean-meal with different levels of 00-rapeseed-meal in dairy cows’ diets, to evaluate the possibility to include it in Parmigiano Reggiano regulation. The study had a Latin square design with 8 tie stall dairy cows. The isoenergetic and isoproteic dietary treatments differed in protein source (% of DM): S (0.0% 00-rapeseed-meal, 9.3% of soybean-meal), LR (3.8% 00-rapeseed-meal, 6.8% of soybean-meal), MR (8.5% 00-rapeseed-meal, 3.4% of soybean-meal), and HR (13.2% 00-rapeseed-meal, 0.0% of soybean-meal). DMI, milk production and composition, rumination and reticular-pH were recorded daily. Dietary fibre digestibility was evaluated by in vitro fermentation and milk gointrin content was quantified by liquid chromatography–tandem mass spectrometry. Statistical analysis was performed by mixed model. Milk yield, protein and casein content increased for incremental 00-rapeseed-meal dietary levels. MR treatment compared to the others resulted in higher daily reticular-pH (5.92), and fewer minutes with pH below 5.8 (467) and 5.5 (72). Goitrin was detectable in milk when 00-rapeseed-meal was included in the diet. Overall, the inclusion of 00-rapeseed-meal in the Parmigiano Reggiano type ratio did not compromise the performances of cows pointing to it as a reliable substitute for soybean-meal. Our results suggest that 00-rapeseed-meal should be tested in feeding studies to determine its effects on milk organoleptic characteristics and cheese production and quality to see if it can be included in the Italian PDO cheese regulation. Highlights 00-rapeseed inclusion on hay-based diet improve DMI, ECM and rumen health 00-rapeseed-meal introduction in Italian PDO cheese regulation is suggested

Immune and Growth Response of Indigenous Pedi Goats Vaccinated with Blanthrax to an Inclusion of Moringa oleifera (Drumstick Tree) in Cenchrus ciliaris (Buffel Grass) Hay-Based Diet

Immune and Growth Response of Indigenous Pedi Goats Vaccinated with Blanthrax to an Inclusion of Moringa oleifera (Drumstick Tree) in Cenchrus ciliaris (Buffel Grass) Hay-Based Diet

Feed intake, digestibility and growth performance of Dorper-Menz cross bred sheep fed local brewery by-product (Atella) and concentrate mixture at different levels of combination

The aim of this experiment was to evaluate the effect of graded level of local brewery by-product (atella) replacement to concentrate mixture on feed intake; digestibility and bodyweight change of Dorper-Menz crossbred lambs fed hay basal diet. The feeding period of 90 days was preceded by 15 days of acclimatization period. The experimental design was randomized complete block design with five treatments: T1 [control, hay ad libtium], T2 [25% atella + 75% concentrate mix]; T3 [50% atella + 50% concentrate mix]; T4 [75% atella + 25% concentrate mix] and T5 [100% atella]. Body weight changes were monitored fortnightly for 112 days. At the end of experiment, animals were fitted with feces collection bags and daily feces excretion was collected for seven days. Fecal output of each animal was thoroughly mixed and 20% of the voided feces were sampled to make a composite of fecal samples for each animal over the collection period. The fecal samples were stored frozen at -20°C until processing for chemical analysis. Data on feed intake, body weight change, and digestibility were subjected to analysis of variance using the General Linear Model procedure. The protein and energy contents of atella are high enough to increase intake, digestibility and could be categorized as medium protein feed. Atella alone or at different level with commercial concentrate mixture has significantly increased body weight gain of crossbred sheep. The positive weight gain results of atella supplemented group clearly indicate supplementation of dried atella could be recommended for fattening Dorper-Menz crossbred male lamb. Atella may lose some volatile nutrients during drying process and further research is needed to compare wet atella with dried one.

Wagyu–Angus cross improves meat tenderness compared to Angus cattle but unaffected by mild protein restriction during late gestation

For the spring-calving beef herds, late gestation coincides with winter and early spring, when cows are dependent on feed supplements with low quality hay, which is hard to meet their nutrient requirements. However, the effects of deficiencies of metabolizable protein intake during late gestation on offspring beef quality are unclear. Wagyu cattle have excellent marbling, and insemination with Wagyu vs Angus semen is a practical option for beef producers to improve beef quality. To test, Angus cows (621 ± 73 kg) were selected and randomly separated into two groups. Each group was inseminated with either Angus or Wagyu semen. During the last 90 days of gestation, cows in each group were further separated and received either a low protein diet (85% of the NRC metabolizable protein requirement), which was a low quality hay-based diet common in northwestern region of the U.S., or an adequate protein diet (108% NRC requirement). All progeny was managed together and harvested at a final BW of 576.5 ± 16.6 kg. Wagyu-sired offspring had higher marbling scores and quality grades than Angus (P < 0.01). Protein supplementation did not affect Slice Shear Force (SSF) in either breeds (P = 0.60). However, Wagyu-sired cattle had lower SSF than Angus-sired (P < 0.01). In addition, Wagyu-sired cattle had higher intramuscular fat (P < 0.05) and total collagen content (P < 0.05), but Angus-sired had greater mature collagen cross-links, as shown by higher contents of Pyridinoline (P < 0.01) and Ehrlich Chromogen (P < 0.01). Consistently, the mRNA expression of enzymes catalyzing collagen cross-linking was higher in Angus-sired offspring, including Plod 1 (P < 0.05), Plod 2 (P = 0.08), and P4Hα 2 (P < 0.01). In conclusion, Wagyu-sired cattle had greater tenderness and marbling score compared to Angus-sired, which was associated with lower collagen cross-links. Feeding mature grass hay-based diet with relatively low protein content during late gestation had no major effect on beef quality of subsequent cattle.

Feeding selenium-biofortified alfalfa hay during the preconditioning period improves growth, carcass weight, and nasal microbial diversity of beef calves.

We previously reported that feeding Se-biofortified alfalfa hay to weaned beef calves in a preconditioning program decreases morbidity and mortality during the feedlot period. To understand the mode of action by which supranutritional Se supplementation supports calf health, we examined the effect of agronomic Se-biofortification on nasal microbiome and fecal parasites. Recently weaned Angus-cross beef calves (n = 30) were randomly assigned to two groups and fed an alfalfa hay-based diet for 9 weeks in a preconditioning program. Alfalfa hay was harvested from fields fertilized with sodium selenate at a rate of 0 or 90 g Se/ha. Calculated Se intake from dietary sources was 1.09 and 27.45 mg Se/calf per day for calves consuming alfalfa hay with Se concentrations of 0.06 and 3.47 mg Se/kg dry matter, respectively. Feeding Se-biofortified alfalfa hay for 9 weeks was effective at increasing whole-blood Se concentrations (556 ± 11 vs 140 ± 11 ng/mL; P < 0.001) and increasing body weight (PTreatment, = 0.03) in weaned beef calves. Slaughter yield grades were higher for calves that had been fed Se-enriched alfalfa hay during the preconditioning period (PTreatment = 0.008). No significant differences were observed in fecal parasite load, which remained low. The nasal microbiome and microbiota diversity within calves and across calves expanded from weaning (week 0) to the feedlot period (week 12), which was promoted by feeding Se-biofortified alfalfa hay. Especially concerning was the expansion of nasal Mycoplasmataceae in the feedlot, which reached over 50% of the total microbiota in some calves. In conclusion, we identified dietary Se-biofortified alfalfa hay as a potential promoter of nasal microbiome genome and microbiota diversity, which may explain in part high-Se benefits for prevention of bovine respiratory disease complex in beef calves.

PSVII-10 Evaluation of different biochar sources added at two inclusion levels in a grass hay- based diet on dry matter disappearance and ruminal fermentation parameters in vitro

Abstract This study evaluated the impact of adding biochar to a grass hay-based diet on in vitro dry matter disappearance (DMD), total gas production (GP), methane production (CH4), volatile fatty acid (VFA) and ammonia nitrogen (NH3-N) concentration. Treatments were arranged in a factorial design with 7 biochar products differing in origin (pine or coconut-based) and physical properties (course, fine or loose spheres) at 2 inclusion levels (2.25% and 4.5% of DM) and a grass hay-only control. On each three successive weeks, rumen fluid was collected from 2 ruminally cannulated beef heifers fed a grass hay-based diet, pooled and mixed with a buffer solution (1:2) and treatments incubated in triplicate for 48 h. Gas pressure was recorded at 3, 6, 9, 12, 18, 24, 36 and 48 h of incubation, and gas was collected at each time to measure CH4. At 48 h, pH was measured and the supernatant sampled for determination of VFA and NH3-N, while the residue was used to estimate DMD. Dry matter disappearance decreased (P &amp;lt; 0.05) with increasing addition of biochar. Biochar did not affect GP or CH4, but did reduce (P &amp;lt; 0.05) gas production per g of DM incubated (111.7 vs 107.8 ml/g), but not per g DMD. The lower GP per g DM incubated could be related to the increased proportion of the diet as biochar, without it contributing to GP. Biochar, irrespective of level did not affect the total or molar proportions of VFA. There was a biochar x inclusion level interaction (P &amp;lt; 0.04) in NH3-N concentration. Biochar type and inclusion level in the present study had little or no significant effect on in vitro fermentation and did not mitigate CH4 production from a grass hay-based diet.

PSVIII-35 Late-Breaking Abstract: Administration of an appeasing substance at castration improves performance of pre-conditioned beef crossbred steers

Abstract Alternatives that alleviate stress-related responses and improve performance of the beef cattle herd are imperative and deserve further investigation. In previous trials, administration of the bovine appeasing substance (BAS) has improved performance of newly-weaned and feedlot received beef animals, as well as reduced the risk of dark, firm, and dry (DFD) cuts in carcass obtained from Bos indicus cattle. Therefore, this study was designed to evaluate the effects of BAS administration at castration on pre-conditioning performance of crossbred beef animals. On day 0, 390 crossbred Angus × Nellore animals were ranked by initial shrunk BW (255 ± 21.1 kg) and assigned to receive or not (CON) 5 mL/head of BAS (SecureCattle; Nutricorp, Araras, SP, Brazil) immediately before castration. From d 0 to 30, animals within treatments were maintained in 2 feedot pens with a minimum distance (300 m) to avoid contact between treatment groups and received a grass hay-based diet (70:30 roughage:concentrate ratio) ad libitum. On day 30, animals were individually weighed following 16 hours of feed and water restriction. Hence, a descriptive analysis was performed to evaluate pen dry matter intake (DMI) and feed efficiency (FE). Animal was considered the experimental unit and all data were analyzed using the PROC MIXED procedure of SAS (version 9.4; SAS Inst. Inc., Cary, NC). Bovine appeasing substance administration at castration improved ADG and BW change (P &amp;lt; 0.0001) compared with CON cohorts (0.983 vs. 1.155 kg/d and 29.5 vs. 34.6 kg for ADG and BW change, respectively). Total DMI was similar among treatments when reported as kg/d (6.70 vs. 6.75 kg) or % of BW (2.48 vs. 2.48%), whereas FE was dramatically improved in BAS-administered animals (146 vs. 172 g/kg for CON and BAS, respectively). In summary, BAS administration improved performance of crossbred beef animals for 30 days post-castration.

Determination of the optimal priming interval of rumen fluids used as inocula for the in vitro digestibility trials through radial enzyme diffusion method

Context Determination of the neutral detergent fibre digestibility is one of the important parameters to consider when formulating diets. However, the in vitro determination shows low repeatability because of the source of rumen-fluid inoculum. Priming of the rumen fluid inocula, obtained through an oesophageal probe, has been proposed to overcome this issue. Aim The objective of the study was to investigate the evolution of the microbial enzymatic activities of different rumen fluids during a priming procedure, to establish the fermentation interval that minimises the differences among rumen-fluid degradative potentials. Methods Three farms for each type of diet were involved in the study. Rumen fluids were obtained from dry and lactating cows fed the following four diet types: 100% hay or a diet with 80:20 forage:concentrate ratio (F:C) as dry-cow diets, and ad libitum hay and concentrate, or a total mixed ration (both at 60:40 F:C) as lactating-cow diets. On each farm, rumen fluid was collected from three Holstein cows by using an oesophageal probe, and mixed. Two aliquots of each rumen fluid mix were added to the medium containing the same priming substrate in an in vitro batch-fermentation system. During the incubation, the fermentation fluids were sampled in duplicate at 0-, 1-, 2-, 4-, 8-, 24- and 48-h intervals. Enzymatic activities of amylase, cellulase and xylanase were determined by radial enzyme diffusion method. Key results Initial enzymatic activities were quite variable and increased with an increasing incubation time. By 24 h, amylase showed similar values among high-concentrate diet fermentation fluids, and a lower data dispersion in comparison to the other intervals; cellulase was characterised by similar values in all the fermentation fluids derived from diets including concentrates, and xylanase showed similar activity in the fermentation fluids derived from high-concentrate diets. Development of the enzymatic activity of the fermentation fluids derived from the 100% hay diet differed from the others. Conclusions A 24-h priming procedure was needed to stabilise and equalise the enzymatic activity of the rumen fluid from cows fed high-concentrate diets. This was not observed in rumen fluid from cows fed hay-based diets. Implications The 24-h-primed rumen fluid can be used to increase the repeatability of neutral detergent fibre digestibility determination.

Effects of the substitution of soybean meal by spirulina in a hay-based diet for dairy cows on milk composition and sensory perception

The demand for protein sources alternative to soybean meal for supplementing forages low in metabolizable protein is large. The suitability of spirulina (Arthrospira platensis), a fast growing and resource-efficient blue-green microalga, as a source of metabolizable protein for dairy cows is known, but its effects on milk antioxidants and sensory properties were never investigated. Twelve cows were allocated to 2 groups and fed hay-based diets complemented with sugar beet pulp and wheat flakes in individual feeding troughs. The N content per kilogram of DM was equivalent between the 2 diets. Diet of 1 group was supplemented with 5% spirulina; the second group was supplemented with 6% soybean meal (control). After an adaptation period of 15 d, data were collected, and feed, milk, blood, and rumen fluid were sampled. Feeds were analyzed for proximate contents, and blood plasma was analyzed for total antioxidant capacity and antioxidant contents (tocopherol, phenols). Milk samples were analyzed for fatty acid profile, coagulation properties, color, and contents of fat, protein, lactose, total phenols, lipophilic vitamins, and provitamins (e.g., β-carotene). Triangle tests were performed by a trained sensory panel on 6 homogenized and pasteurized bulk milk samples per treatment. The substitution of soybean meal by spirulina in the diet did not affect feed intake, milk yield, milk fat, protein, or lactose contents compared with the control group. However, the milk from the spirulina-fed cows had a higher content of β-carotene (0.207 vs. 0.135 μg/mL) and was more yellow (b* index: 14.9 vs. 13.8). Similar to the spirulina lipids but far less pronounced, the milk fat from the spirulina-fed cows had a higher proportion of γ-linolenic acid (0.057 vs. 0.038% of fatty acid methyl esters) compared with milk fat from soybean meal-fed cows. Also trans-11 C18:1 (vaccenic acid) and other C18:1 trans isomers were elevated, but otherwise the fatty acid profile resembled that of cows fed the control diet. No sensory difference was found between milk from the 2 experimental groups. Furthermore, we observed no effects of substituting soybean meal by spirulina on total antioxidant capacity, α-tocopherol and total phenols in blood and milk. Effects on rumen fluid characteristics were minor. In conclusion, spirulina seems to be a promising protein source for dairy cows with certain improvements in nutritionally favorable constituents in milk and without side-effects on animal performance in the short term.

Influence of pelleted browse-based supplements fed with a basal diet of Andropogon gayanus hay on intake, digestibility, growth and haemato-biochemical indices in West African Dwarf goat

Influence of pelleted browse-based supplements fed with a basal diet of Andropogon gayanus hay on intake, digestibility, growth and haemato-biochemical indices in West African Dwarf goat

Effect of Feeding Graded Levels of Wild Silver Leaf Desmodium (Desmodium Uncinatum) on Growth and Bodyweight Change of Horro Sheep Fed Basal Diet of Natural Pasture Hay

Effect of Feeding Graded Levels of Wild Silver Leaf Desmodium (Desmodium Uncinatum) on Growth and Bodyweight Change of Horro Sheep Fed Basal Diet of Natural Pasture Hay