Grass Hay Research Articles

Effects of a Bacillus-based direct-fed microbial on in vitro nutrient digestibility of forage and high-starch concentrate substrates.

Two experiments evaluated the effects of a Bacillus-based direct-fed microbial (DFM) on in vitro dry matter (DM) and neutral detergent fiber (NDF; experiment 1) and starch (experiment 2) digestibility of a variety of ruminant feedstuffs. In experiment 1, 10 forage sources were evaluated: ryegrass, alfalfa hay, leucaena, corn silage, spinifex, buffel grass, flinders grass, Mitchell grass, Rhodes grass hay, and Queensland bluegrass. Experimental treatments were control (forages with no probiotic inoculation; CON) and forage sources inoculated with a mixture containing Bacillus licheniformis and Bacillus subtilis (3.2 × 109 CFU per g; DFM). In vitro DM and NDF digestibility were evaluated at 24- and 48-h post-treatment inoculation. Treatment × hour interactions were noted for IVDMD (in vitro dry matter digestibility) and IVNDFD (in vitro neutral detergent fibre digestibility) (P ≤ 0.05). More specifically, DFM inoculation increased (P ≤ 0.03) IVDMD at 24 h in four forages and increased 48-h IVDMD (P ≤ 0.02) in alfalfa hay, ryegrass, leucaena, and Mitchell grass hay, but opposite results were observed for Queensland bluegrass (P < 0.01). A 24- and 48-h IVNDFD increased following DFM inoculation (P ≤ 0.02) in five forage sources, but reduced for Queensland bluegrass (P < 0.01). When the forages were classified according to their quality, main treatment effects were detected for IVDMD (P ≤ 0.02) and IVNDFD (P < 0.01). In experiment 2, five common cereal grains were evaluated—high-density barley (82 g/100 mL), low-density barley (69 g/100 mL), corn, sorghum, and wheat—under the same treatments as in experiment 1. In vitro starch digestibility (IVSD) was evaluated at 6- and 12-h following treatment inoculation. Treatment × hour interactions were observed for starch digestibility in three out of five concentrate sources (P ≤ 0.001). Inoculation of DFM yielded greater 24-h starch digestibility for high-, low-density barley, and wheat (P ≤ 0.02), but also greater at 48 h in wheat (P < 0.0001). Moreover, mean starch digestibility improved for corn and sorghum inoculated with DFM (P < 0.01). Using a Bacillus-based DFM (B. licheniformis and B. subtilis) improved the mean in vitro DM and NDF digestibility of different forage sources of varying qualities (based on crude protein content). Similarly, IVSD was also greater following DFM inoculation, highlighting the potential of this probiotic to improve nutrient digestibility and utilization in the beef and dairy cattle herd.

Interaction of urea with frequency and amount of distillers grains supplementation for growing steers on a high forage diet.

Two studies were conducted to determine interactions of urea inclusion to a dried distillers grains plus solubles (DDGS; 29.4% crude protein, 5.48% ether extract) supplement fed at two amounts and two frequencies to steers on a high forage diet. In Exp. 1, 120 (247 kg; SD = 20) steers were fed individually for 84 d. Steers received ad libitum grass hay (6.8% crude protein) and one of eight treatments. Treatment design was a 2 × 2 × 2 factorial. Supplement was fed daily or three times per week, amount of supplement fed was 6.36 kg dry matter (DM)/week [0.37% body weight (BW); LO] or 12.73 kg DM/week (0.74% BW; HI) and contained either no urea or 1.3% urea on a DM basis. Steer BW was measured at the start and end of the trial and hay DM intake (DMI) was measured weekly. In Exp. 2, ruminally cannulated steers (310 kg; SD = 25) were used in a row-column design with eight steers and six 14-d periods. Treatments assigned were the same as Exp. 1, except that supplement was fed at 0.4% of BW (LO) or 0.8% of BW (HI) and supplement was fed either daily (DY) or every other day (ALT). Hay DMI, rumen ammonia-N, rumen pH, in situ neutral detergent fiber (NDF) disappearance, and rumination were measured. In Exp. 1, average daily gain (ADG) was affected by amount of supplement with steers on HI gaining 0.30 kg/d more (P < 0.01) than LO. Hay DMI was reduced by increased amount of supplement (0.39 kg/d; P < 0.01) and by decreased frequency of supplementation (0.54 kg/d; P < 0.01). In Exp. 2, hay DMI was also reduced due to increased amount of supplement and decreased frequency of supplementation (P < 0.01). Rumen pH was decreased on the day of supplement feeding for steers on ALT (P < 0.01) and reduced for steers fed HI vs. LO. There was no difference in NDF digestibility between DY and ALT (P > 0.05). For ALT steers, there was reduction (P < 0.01) in in situ NDF disappearance for the HI compared to LO amount of supplementation on the day of supplementation. Infrequent supplementation of DDGS results in no difference in ADG but decreased hay DMI compared to daily supplementation. Urea had no effect on digestion or ADG, suggesting rumen degradable protein was not deficient when supplementing DDGS. There is little change in rumen fermentation parameters between frequency of supplement feeding, indicating that forage digestion is not impacted by supplementation frequency. Dried distillers grains can be supplemented infrequently without a reduction in animal performance.

Impacts of added roughage on growth performance, digestibility, ruminal fermentation, and ruminal pH of feedlot steers fed wheat-based feedlot diets containing 30% modified distillers grains with solubles.

Two experiments were conducted to evaluate the inclusion rate roughage in wheat-based diets containing modified distillers grains with solubles (MDGS) on feedlot performance (Feedlot Experiment), as well as digestibility, ruminal pH, and ruminal fermentation characteristics (Digestibility Experiment). The feedlot experiment utilized 72 Angus steers (392 ± 46.3 kg initial body weight) which were randomly assigned to 1 of 12 pens, 3 pens per treatment, to evaluate feedlot performance and carcass characteristics. Dietary treatments were 1) control; 10% roughage, 2) 12% roughage, 3) 14% roughage, and 4) 16% roughage. The digestibility experiment used four ruminally and duodenally cannulated steers (393 ± 33.0 kg) in a 4 × 4 Latin Square with either 10%, 12%, 14%, or 16% roughage as in the feedlot experiment. However, dietary roughage source was different between these two experiments and included a combination of grass hay and wheat straw (Feedlot Experiment), and corn silage (Digestibility Experiment). All data were analyzed with the Mixed Procedures of SAS. Feed intake was recorded, with duodenal and fecal output calculated using chromic oxide. Ruminal pH and fermentation were assessed. Growth performance and most carcass characteristics were not affected by increasing roughage (P ≥ 0.11). Marbling tended to decrease linearly (P = 0.10) with increasing roughage inclusion. Increasing dietary roughage content had no effect on organic matter intake (P = 0.60) in the digestibility experiment. Intake, duodenal flow, and digestibility of neutral detergent fiber and acid detergent fiber were not affected by treatment (P ≥ 0.16). Ruminal pH increased linearly (P < 0.01) as rate of roughage inclusion increased. Ruminal concentrations of acetate and butyrate increased, and propionate decreased in a linear fashion (P < 0.01) thereby increasing (P < 0.01) acetate and butyrate to propionate ratio with increasing dietary roughage. Our data indicate that increasing roughage inclusion in wheat-based diets including 30% MDGS increased ruminal pH and shifted ruminal fermentation patterns. Additionally, increasing roughage inclusion did not affect feedlot performance in steers fed wheat at 36% to 42% of dietary dry matter in combination with 30% MDGS.

PARTIAL SUBSTITUTION OF CONCENTRATE MIX WITH DRIED Leucaena leucocephala LEAF REDUCED in vitro METHANE PRODUCTION IN RAMS WITHOUT AFFECTING THE NUTRIENT INTAKE AND PERFORMANCE TRAITS

&lt;p&gt;&lt;strong&gt;Background.&lt;/strong&gt; Through &lt;em&gt;in vitro&lt;/em&gt; studies, dried &lt;em&gt;Leucaena leucocephala&lt;strong&gt; &lt;/strong&gt;&lt;/em&gt;leaf (DLL) was identified as potential candidate in mitigating enteric methane (CH&lt;sub&gt;4&lt;/sub&gt;) emission. Nevertheless, its efficiency as suitable feed for sheep has not been determined in Ethiopia&lt;strong&gt;. Objective.&lt;/strong&gt; To assess the suitability of replacing the concentrate mix (CM) with DLL on voluntary intake, growth performance in rams and &lt;em&gt;in vitro&lt;/em&gt; CH&lt;sub&gt;4&lt;/sub&gt; production. &lt;strong&gt;Methodology.&lt;/strong&gt; Thirty yearling rams were first stratified according to their initial body weight similarities and then individuals from each stratum were randomly assigned to five treatment diets with six rams each. The control diet contained CM with 346 g/head/d (T1), and treatment diets replacing the CM in the control diet with DLL at a rate of 5% (T2), 10% (T3), 15% (T4) and 20% (T5) with the corresponding CM to DLL mixture ratio of 346:0, 329:17, 311:35, 294:52 and 277:69 g/head/day. Grass hay was provided &lt;em&gt;ad libitum&lt;/em&gt; to all rams. Data were collected on fed intake and body weight. Methane (CH&lt;sub&gt;4&lt;/sub&gt;) production was determined along with 24h &lt;em&gt;in vitro&lt;/em&gt; gas production (GP). Digestible organic matter (DOM) and Metabolizable energy (ME) were estimated from 24h GP. &lt;strong&gt;Results. &lt;/strong&gt;The contents of ash, crude protein (CP), neutral detergent fiber (NDFom), acid detergent fiber (ADFom) and acid detergent lignin were higher in DLL than in the control diet while it contained the lowest EE value. The DLL had the highest Ca and K values as compared to the control diet. The feed intake, live weight and weight gain did not differ (P&amp;gt;0.05) among rams supplemented with various levels of DLL. The total intake of CP increased across treatment diets and was significantly higher for T3, T4 and T5 than T1 and T2 diets. None of the supplementation levels of &lt;em&gt;L. leucocephala&lt;/em&gt; affected the total intake of DM, NDFom and ADFom. There was a linear reduction (p&amp;lt;0.05) of &lt;em&gt;in vitro&lt;/em&gt; CH&lt;sub&gt;4&lt;/sub&gt; production as the levels of DLL in the diet were increased. It was lowest in T4 and T5 diets being significantly different from those of T1 and T2. The T5 diet showed the lowest values and differed (p&amp;lt;0.05) from those of T1, T2 and T3. The ME and DOM values were higher (p&amp;lt;0.05) in T1 and T2 diets than that of T4 and T5. No difference in ME and DOM values were observed between T1, T2 and T3 diets as well as among T4 and T5 diets. &lt;strong&gt;Implications.&lt;/strong&gt; The current findings suggest that conventional CM could be replaced with DLL up to 20% as alternative protein source in ruminant nutrition in tropical and sub-tropical regions. &lt;strong&gt;Conclusion&lt;/strong&gt;. The replacement of CM with DLL significantly reduced the &lt;em&gt;in vitro&lt;/em&gt; CH&lt;sub&gt;4&lt;/sub&gt; production across treatment diets without affecting the voluntary intake and growth performance parameters in rams.&lt;/p&gt;

Calibration of laboratory derived indices for non-target arthropod risk assessment with field data for plant protection products

The Hazard Quotient (HQ) compares field application rate to intrinsic toxicity assessed with sensitive indicator species. As a hazard indicator for risk assessment, the HQ must be calibrated against measured effects under field conditions. Because protection goals may be context specific, we analyse how choice of acceptance criteria affects setting of the HQ and calibrate HQ for various scenarios under the strict condition that no false negative conclusions may be reached. We use Non-Target Arthropod toxicity data from laboratory studies on inert (Tier 1) and on natural substrates (Tier 2) and calibrate the HQ using application rates and arthropod abundance counts from field studies in orchards, arable fields, and hay meadows in 34 locations in Western Europe. With 21 formulations (17 active substances) tested in mostly multi-rate field studies, our reference data base has 120/121 values at Tier 1/Tier 2, respectively. We use the Proportion of Affected Taxa and Duration of Effect to jointly define acceptance criteria, starting with No Observed Effects. Absence of field effects is correctly predicted with HQ < 1.3 at Tier 1 and HQ < 0.48 at Tier 2, but these settings result in a high proportion of false positive outcomes. Increasing accepted duration of effect from 0 to 4 to 8 weeks results in HQ-threshold changes from 1.3 to 6.4 to 250 for Tier 1 studies and from 0.48 to 1.1 to 5.7 for Tier 2 studies. This coincides with a clear decrease in false positive outcomes. Recovery within a year is correctly concluded for 73% of the products passing the corresponding Tier 1 HQ < 2600 and for 92% of products at Tier 2 (HQ <230). Our analysis shows that the calibration is appropriate for a broad geographical range, for in-field and off-field situations and for phytophagous and non-phytophagous species alike.

Isoflavone Containing Legumes Mitigate Ergot Alkaloid-Induced Vasoconstriction in Goats (Capra hircus).

Simple SummaryWhen endophyte-infected tall fescue is consumed by grazing livestock it can cause persistent vasoconstriction resulting in fescue toxicosis. Legumes are commonly utilized in livestock production to improve diet quality. Legumes also contain vasodilatory isoflavones that have been shown to alleviate fescue toxicosis in goats and grazing cattle. Different legumes contain varying levels and types of isoflavones. A pen study was conducted to determine if isoflavone supplementation via red clover, white clover, or soybean meal can mitigate vasoconstriction associated with fescue toxicosis in goats. Rumen fistulated Wether goats were assigned to each legume treatment at equal levels of supplementation by weight. Goats were subjected to a fescue toxicosis challenge with toxic tall fescue seed, and the carotid artery area was monitored using Doppler ultrasonography. All isoflavone treatments were able to partially mitigate vasoconstriction. Red clover, with the greatest concentration of isoflavones, was the most effective. These results demonstrate that red clover, white clover, and soybean meal supplementation can be used to reverse the vasoconstriction associated with fescue toxicosis in goats despite differences in isoflavone concentration and composition. The impact of this research is a legume-derived phytochemical that can be applied in ruminants consuming toxic tall fescue to reverse fescue toxicosis and improve animal health and productivity.Ergot alkaloids produced by a fungal endophyte that infects tall fescue (Lolium arundinaceum; (E+ TF) can induce constriction of the vasculature in ruminants, resulting in “fescue toxicosis”. Legumes contain isoflavones that have been demonstrated to prevent and reverse E+ TF vasoconstriction. Several legumes are conventionally utilized in ruminant production, but can vary in both isoflavone concentration and composition. A feeding study was conducted to determine if isoflavone supplementation via red clover (Trifolium pratense), white clover (Trifolium repens), or soybean (Glycine max) meal can alleviate vasoconstriction when wether goats were challenged with E+ TF seed. The basal diet was chopped grass hay ad libitum. Carotid luminal areas were obtained pre- and post-ruminal infusions of E+ TF seed (15 µg kg BW−1 ergovaline + ergovalanine ± red clover, white clover, or soybean meal at 2.61 mg kg BW−1). When goats were challenged with E+ TF seed, the mean carotid luminal areas decreased by 56.1% (p < 0.01). All treatments were able to partially mitigate vasoconstriction, with red clover being the most effective (+39.8%), and white clover and soybean meal eliciting an intermediate response (+30%, p < 0.01). Results indicate that legumes can relax vasoconstriction in goats consuming ergot alkaloids, despite differences in isoflavone profile and concentrations.

Intensive grazing alters the diversity, composition and structure of plant-pollinator interaction networks in Central European grasslands.

Complex socio-economic, political and demographic factors have driven the increased conversion of Europe’s semi-natural grasslands to intensive pastures. This trend is particularly strong in some of the most biodiverse regions of the continent, such as Central and Eastern Europe. Intensive grazing is known to decrease species diversity and alter the composition of plant and insect communities. Comparatively little is known, however, about how intensive grazing influences plant functional traits related to pollination and the structure of plant-pollinator interactions. In traditional hay meadows and intensive pastures in Central Europe, we contrasted the taxonomic and functional group diversity and composition, the structure of plant-pollinator interactions and the roles of individual species in networks. We found mostly lower taxonomic and functional diversity of plants and insects in intensive pastures, as well as strong compositional differences among the two grassland management types. Intensive pastures were dominated by a single plant with a specialized flower structure that is only accessible to a few pollinator groups. As a result, intensive pastures have lower diversity and specificity of interactions, higher amount of resource overlap, more uniform interaction strength and lower network modularity. These findings stand in contrast to studies in which plants with more generalized flower traits dominated pastures. Our results thus highlight the importance of the functional traits of dominant species in mediating the consequences of intensive pasture management on plant-pollinator networks. These findings could further contribute to strategies aimed at mitigating the impact of intensive grazing on plant and pollinator communities.

33 Dietary Impacts on Rumen, Vaginal, and Uterine Microbiota in Beef Heifers

Abstract This experiment investigated the effects of diet composition on rumen, vaginal, and uterine microbiota of beef heifers. Fifteen rumen-cannulated, pubertal Angus-influenced heifers were used in a replicated 3 x 3 Latin square design (28-d periods and 21-d washout intervals). Dietary treatments included diets based on (as-fed) 100% grass hay (HF), 61% grass hay + 39% corn-based concentrate (INT), or 25% grass hay + 75% corn-based concentrate (HG). Treatments were offered individually to heifers once daily at 2% BW. Heifers also received 280 g/d of a mineral mix containing melengestrol acetate. Rumen, vaginal, and uterine samples were collected on d 0 and 28 of each period for bacterial profiling of the 16S rRNA gene and pH measurement. Data were analyzed using the MIXED procedure of SAS using results from d 0 as independent covariates, and heifer as the experimental unit. Ruminal pH on d 28 was greater (P &amp;lt; 0.01) in HF compared with INT and HG, and greater (P &amp;lt; 0.01) in INT compared with HG. Uterine and vaginal pH on d 28 did not differ among treatments (P &amp;gt; 0.10). In the rumen, Bacteriodetes was the most abundant phylum with the relative abundance being significantly greater (P &amp;lt; 0.01) in HF and INT (64.9 and 62.6%, respectively) when compared with HG (53.9%). Prevotella was the most abundant genus of bacteria within the rumen but did not differ (P &amp;gt; 0.10) by dietary treatment. While there were no significant differences (P &amp;gt; 0.10) for bacterial phyla in vaginal samples, Prevotella was the most abundant genus with the relative abundance being significantly greater (P &amp;lt; 0.01) for the HG (18.62%) when compared with HF and INT (7.78 and 10.35%, respectively). There were no significant differences (P &amp;gt; 0.10) for bacterial phyla in uterine samples, and while Prevotella was the most abundant, it was unaffected (P &amp;gt; 0.10) by diet. Therefore, diet impacted rumen microbiota and appears to have an influence on vaginal microbiota of beef heifers.

132 Ranking Beef Heifers for Residual Intake Using an Unprocessed Grass Hay Diet and Its Relationship to Greenhouse Gasses

Abstract The objective of this study was to rank beef heifers for residual feed intake and greenhouse gas emissions using an unprocessed, grass hay diet. Fifty yearling Angus heifers were monitored for 62 days using the SmartFeed individual intake measuring technology (C-Lock Inc., Rapid City, SD) in drylot pens at the Oklahoma State University Range Cow Research Center located in Stillwater, OK. Means ± SD for dry matter intake (DMI; 6.76 ± 1.20 kg), average daily gain (ADG; 0.51 ± 0.21 kg), body weight (BW; 338.67 ± 55.24 kg), and residual feed intake (RFI; -0.04 ± 0.80 kg) were recorded while the heifers were fed unprocessed long-stem grass hay (10.3% CP, 2.0 Mcal ME, and 56% TDN). Additionally, a subset of 29 heifers were subjected to the collection of gas flux data using an open-circuit, portable, gas-quantification system (GreenFeed, C-Lock Inc., Rapid City, SD) to measure (means ± SD) oxygen consumption (O2; 3979.51 ± 510.32 g), carbon dioxide production (CO2; 5299.65 ± 610.89 g), and methane production (CH4; 202.656 ± 28.30 g). Using R, RFI was calculated using a multiple regression equation to predict DMI using BW0.75 and ADG (P &amp;gt; 0.05; R2 = 0.37). To analyze forage utilization efficiency, heifers were classified into three RFI categories consisting of efficient (n = 16), average (n = 16), and inefficient (n =18). The ADG was low for all RFI classifications and similar for all three categories (P &amp;lt; 0.05). Heifers classified in the top third of RFI rank consumed 22% less forage per day compared to the inefficient heifers. The phenotypic correlation between DMI with CO2, CH4, and O2 was 0.66, 0.18, and 0.49, respectively. These data suggest that progress in feed efficiency can be achieved when cattle are tested using a moderate-quality, unprocessed forage diet.

133 Ranking Mature Beef Cows for Residual Intake Using an Unprocessed Grass Hay Diet and Its Relationship to Greenhouse Gas Exchange

Abstract The objective of this study was to compare high and low residual feed intake (RFI) beef cows when consuming an unprocessed, grass hay diet (93% DM, 8.73% CP, 2.11 Mcal ME, and 59.25% TDN). Relationships of hay intake to carbon dioxide (CO2) and methane (CH4) production were also evaluated. Thirty-six mature Angus and Angus x Hereford cows were assigned randomly to five pens (n = 6 or 9) and individual feed intakes were collected for 52-d using SmartFeed intake units (C-Lock Inc., Rapid City, SD) at a stocking rate of 3 cows per feeder. An open-circuit, gas-quantification system (GreenFeed, C-Lock Inc., Rapid City, SD) was used to collect CO2 (7611.63±714.09 g) and CH4 (283.64±37.10 g) production for 9 days of collection per pen for a minimum of 20 visits per cow (n = 22 cows, 36.18±14.24 visits). Data collection on cows included (means ± SD) dry matter intake (DMI; 13.86±2.16 kg), metabolic body weight (MBW, 111.65±9.28 kg), average daily gain (ADG, 0.77±0.29 kg), and rib eye area by ultrasound (REA, 46.62±6.34 cm).To calculate RFI (0.03±1.71), a multiple regression model was used to predict DMI (PDMI = ADG + REA + MBW; R2=0.50, P = 0.001). Cows were categorized into three RFI classes: low (n = 7), moderate (n = 6), and high (n = 9). Differences between RFI and RFI class and DMI and RFI class were analyzed using PROC MIXED in SAS (SAS, Cary, NC). Low RFI cows (-1.81 kg) consumed 12.08 kg hay DM daily and high RFI cows (1.59 kg) consumed 15.27 kg hay DM daily (P &amp;lt; 0.001). Correlations between DMI and daily gas exchange were estimated using PROC CORR in SAS (SAS, Cary, NC). Pearson Correlation Coefficients were significant between DMI and CO2 (r=0.58, P = 0.004), and CH4 (r=0.70, P &amp;lt; 0.001) production. Differences in feed intake for high and low RFI rankings were similar to previously reported literature when growing cattle consumed energy-dense diets.

Effects of incremental increases in grass silage proportions from different harvest years on methane emissions, urinary nitrogen losses, and protein and energy utilisation in dairy cows.

Dairy cows, methane and global warming have become publicly related terms. However, appropriate dairy cow management may in fact be part of the climate solution when viewed as part of the biogenic carbon cycle. Accordingly, governments and consumers are encouraging more sustainable, locally produced, climate friendly dairy production that often includes grassland-based feeding. However, this system is presumed to result in greater methane emissions compared to corn silage- or concentrate-based diets. An increase in urine nitrogen, associated with increased ammonia and nitrous oxide emission potential, questions the environmental usefulness of this strategy pertaining to global warming. This study is the first to compare the effects of incremental increases of grass silage proportion on enteric methane production as well as N and energy losses in dairy cows. Twenty-four mid- to end-lactation dairy cows were each fed one of 24 different diets, from two different harvest years, gradually increasing in grassland-based feeds (grass silage and hay) from about 500 to 1000 g/kg and concomitantly decreasing in corn silage. Each cow underwent a 7-day total collection period and was housed for 48 h in respiration chambers. Incremental data were subjected to an approved parametric regression analysis approach. The dietary increase in grassland-based feeds did not impair milk yield, N and energy utilisation. Simplified regression equations revealed that, contrary to current assumptions, there was a decline in methane production from 373 to 303 g/day when increasing grassland-based feeds from 500 to 1000 g/kg diet, and there was a trend for a decline in emission intensity from 20.6 to 17.6 g/kg of energy-corrected milk. However, urine nitrogen emissions clearly increased even when related to nitrogen intake; the latter from 260 to 364 g/kg when increasing grassland-based feeds from 500 to 1000 g/kg. Methane and urine nitrogen emissions were not affected by year of harvest.

Meta-analysis of the effects of chemical and microbial preservatives on hay spoilage during storage.

A meta-analysis was performed to evaluate the effects of chemical (50 articles) and microbial (21 articles) additives on hay preservation during storage. Multilevel linear mixed-effects models were fit with response variables calculated as predicted differences (Δ) between treated and untreated samples. Chemical preservatives were classified into five groups such as propionic acid (PropA), buffered organic acids (BOA), other organic acids (OOA), urea, and anhydrous ammonia (AA). Moderators of the models included preservative class (PC), forage type (FT; grass, legumes, and mixed hay), moisture concentration (MC), and application rate (AR). Dry matter (DM) loss during storage was affected by PC × FT (P = 0.045), PC × AR (P < 0.001), and PC × MC (P = 0.009), relative to the overall effect of preservatives (-0.37%). DM loss in PropA-treated hay was numerically reduced to a greater extent in grasses (-16.2), followed by mixed hay (-1.76), but it increased (+2.2%) in legume hay. Increasing AR of PropA resulted in decrease in DM loss (slope = -1.34). Application of BOA, OOA, PropA, and AA decreased visual relative moldiness by -22.1, -29.4, -45.5, and -12.2 percentage points, respectively (PC; P < 0.001). Sugars were higher in treated grass hay (+1.9) and lower in treated legume hay (-0.8% of DM) relative to their untreated counterparts (P < 0.001). The application of all preservatives resulted in higher crude protein (CP) than untreated hay, particularly urea (+7.92) and AA (+5.66% of DM), but PropA, OOA, and BOA also increased CP by 2.37, 2.04, and 0.73 percentage points, respectively. Additionally, preservative application overall resulted in higher in vitro DM digestibility (+1.9% of DM) relative to the untreated hay (x¯=58.3%), which increased with higher AR (slope = 1.64) and decreased with higher MC (slope = -0.27). Microbial inoculants had small effects on hay spoilage because the overall DM loss effect size was -0.21%. Relative to untreated (x¯=4.63% DM), grass hay preserved more sugars (+1.47) than legumes (+0.33) when an inoculant was applied. In conclusion, organic acid-based preservatives prevent spoilage of hay during storage, but their effectiveness is affected by FT, MC, and AR. Microbial inoculants had minor effects on preservation that were impaired by increased MC. Moreover, legume hay was less responsive to the effects of preservatives than grass hay.

Productive performance and ingestive behaviour of feedlot finished Santa Ines lambs on diets containing differing fibre levels

ABSTRACT The aim of this study was to determine the ideal level of neutral detergent fibre (NDF) that maximises productive performance and to evaluate the ingestive behaviour of feedlot Santa Inês lambs. Diets consisted of Tifton 85 grass hay (Cynodon sp.), with particle size from 1 to 2 cm, and concentrate, and the treatments were represented by different NDF levels (20, 32, 44, 56 and 68% NDF dry matter). There was a quadratic effect (P < 0.05) for the intake of dry matter, organic matter and crude protein, with maximum intake estimated at 27, 26 and 27% NDF. There was a quadratic effect (P < 0.05) for digestibility of crude protein and NDF, with the lowest digestibility estimated at 40 and 37% NDF. There was a quadratic effect (P < 0.05) for weight gain, average daily gain and feed efficiency, with maximum gains estimated at 27, 29 and 30% NDF. There was an effect (P < 0.05) of NDF levels on variables of ingestive behaviour periods/day of feeding, rumination and idle. For the feedlot Santa Inês lambs fed diets based on Tifton 85 grass hay, we recommend 27 - 30% neutral detergent fibre.

Microbiological Composition of Diets of Cactus Pear-Based with Increasing Levels of Buffel Grass Hay and Relationship to Nutritional Disorders in Sheep.

Simple SummarySmall ruminants fed on cactus pear exclusively in the diet may present nutritional disorders, especially diarrhea. This is due to the high moisture requirements present in this food, related to microbiological factors inherent to poor hygienic quality, such as handling and prolonged exposure of crushed palm to the air, which can cause greater ingestion by animals of certain bacterial groups with pathogenic potential. The aim of this research was to investigate the levels of cactus associated with buffel grass hay on the microbiological quality of diets and the influence on physiological parameters in sheep. Thus, this research revealed that the participation of buffel grass hay was able to reduce the contamination of bacteria that cause diarrhea and depress animal performance.This study aimed to evaluate the microbiological composition of cactus pear-based diets with increasing levels of buffel grass hay, and its effect on the blood and physiological parameters and occurrence of diarrhea in feedlot sheep. Four diets containing different percentages of buffel grass hay were tested. Diets were composed of forage cactus, buffel grass hay and concentrate, and the treatments were represented by different levels of hay in the dry matter of the feed: 7.5% buffel grass hay; 15% buffel grass hay; 30% buffel grass hay; and 45% buffel grass hay on a dry matter basis. There was a significant effect (p = 0.0034) of inclusion levels of buffel grass hay on fecal score. Only at the 45% inclusion level diarrhea was not observed, showing that the level of buffel grass affected more the animals than the collection period, although the collection period has affected the microbial counts. Probably there was a physiological adaptation of animals over time. There were significant changes (p < 0.0001) in the blood parameters of sheep. The reduction of the proportion of cactus and the inclusion of greater than 15% buffel grass hay, on a dry matter basis, provides less contamination of the diet and animal feces by enterobacteria, such as E. coli.

Mid- and long-term responses of land snail communities to the intensification of mountain hay meadows management

BackgroundSpecies-rich semi-natural grasslands are impacted by the severe land-use changes that are affecting mountain regions, compromising their high biodiversity value. In particular, sprinkler irrigation and increased fertilisation stimulate vegetation growth, modifying and homogenising habitat conditions for ground-dwelling invertebrates. Among them, land snails have been largely understudied despite their commonness and vulnerability to small-scale habitat alteration. This study investigated the mid- and long-term responses of land snail communities to management intensification of montane and subalpine hay meadows. Mid-term effects were studied using a randomised block design experiment, mimicking an intensification gradient with different levels of irrigation and fertilisation applied during 5 years. Long-term effects were examined relying on an observational approach that consisted in comparing snail communities in meadows managed intensively for > 20 years with those from the 5-year experimental module.ResultsWe show that management intensification initially boosts snail densities, but erodes species richness by − 35% in intensively-managed meadows in the long term. Contrary to our expectations, drought-tolerant (xerophilous) snails benefitted from grassland intensification, whereas mesophilous species accounted for most species losses due to intensification in the long run, indicating that the latter may be especially sensitive to the hostile microclimate conditions abruptly prevailing in a meadow after mowing. Soil pH was also a principal determinant of land snail occurrence, with almost no specimen recorded in acidic meadows (pH < 5.5), while plant diversity favoured overall snail abundance.ConclusionsDespite the fact that xerophilous snails appear tolerant to management intensification, we found that several drought-sensitive species are lost in the long term. We conclude that the preservation of species-rich land snail communities in mountain hay meadows requires the conservation and restoration of low-input grasslands on basic soils for preventing further species losses of gastropod fauna.

Value in grass

Climate adaptation is a major challenge. Chasing the sufficient amount of hay is getting in higher priority. Distant mass hay producers give favourable offers despite long distances. Quality is also gaining position and indicators like RFQ (Relative Forage Quality) is highlighting the marketing language. Hay market as we knew no longer exists in Hungary. Most farmers produce their own hay and do not spend extra cents to buy bales. Climate change however, force them to adapt and store more bales for the future. Horse owners and dairy farmers are the main driver to convince hay producers to provide high quality forage. We gathered Hungarian regional hay-price information and evaluated the trends in this sector. The demand-driven hay-price is in contradiction with premium quality timothy grass hay. JEL code: Q11

Growth and reproductive performance responses to post-weaning supplementation of early and normally-weaned Brahman crossbred heifers raised in tropical rangelands.

This study investigated the effect of five post-weaning supplementation strategies and two weaning weight groups on long-term growth, puberty and pregnancy percentage of Brahman crossbred heifers. Early-weaned (118 ± 6 kg liveweight) and normally-weaned (183 ± 6 kg liveweight) heifers were allocated to group pens (n = 4 and n = 5/pen for early- and normally-weaned respectively) and offered one of five levels of post-weaning protein supplementation: 0, 1, 2.5, 5 and 10 g of supplement/kg liveweight.day with ad libitum access to a low quality sabi grass (Urochloa mosambicensis) hay during the first dry season (169 days) after weaning. After the post-weaning supplementation period, all heifers grazed the same pastures as a single mob until the end of the experiment and were exposed to fertile bulls from January to May 2016. During the first dry season, supplement intake had a positive linear effect on liveweight gain and hip width gain with no difference in the response between weaning groups. Overall, heifers with higher supplement intakes (i.e. 5 and 10 g/kg) had higher hip height gain (P < 0.005), hip width gain (P < 0.001), body condition score (P < 0.001), and concentration of insulin-like growth factor-1 (P = 0.001), triiodothyronine (P = 0.04) and insulin (P = 0.05) in plasma compared to unsupplemented heifers. These changes resulted in thicker proliferative and hypertrophic zones (both P = 0.03) of the tuber coxae growth plate, larger diameter of terminal hypertrophic chondrocytes (both P = 0.004) at the end of the post-weaning supplementation period when comparing the highest level of supplementation with unsupplemented group. Unsupplemented heifers from both weaning weight groups demonstrated compensatory liveweight gain over the first wet season while evidence of catch-up growth in skeletal dimensions was observed in the second wet season. The main determining factor for pregnancy status of two-year-old Brahman crossbred heifers was pre-mating liveweight (P < 0.001), the pre-mating liveweight was in turn affected by post-weaning supplementation (P = 0.02) or weaning weight group (P < 0.001). This study further demonstrated the positive relationship between premating weight and the occurrence of pregnancy, with an approximate 300 kg pre-mating liveweight required to achieve approximately 80% (67.1–90.3% for a 95% confidence interval) probability of pregnancy in two-year-old Brahman crossbred heifers mated for 4 months.

Strong conditionality in plant-fungal community assembly after soil inoculation in post-agricultural grasslands

Soil inoculation from plant species-rich into species-poor grasslands may enable the establishment of self-facilitating networks between microbes and vegetation, thereby steering ecosystem development.We conducted a three-year experiment that covered a wide range of post-agricultural grasslands to determine how succession is affected by the interactive effects of edaphic properties, grass layer removal and hay or soil fragment transfer from a late-successional donor grassland.Soil inoculation generally impacted community assembly of vegetation and fungi, but not of prokaryotes. Effects were strongest when preceded by removal of the grass layer, indicating the importance of priority effects and dispersal limitation. Inoculation enabled the establishment of putative rhizosphere-associated fungal taxa, particularly from the families Helotiaceae, Glomeraceae and Archaeorhizomycetaceae. Nonetheless, effect sizes were mostly small, as was overall resemblance of the receptor grasslands to the donor. Fungal communities were primarily shaped by environmental filters and only reached a high resemblance to the donor in nutrient-poor sites. Shifts in the vegetation were strongest in those grasslands where the mycobiome more closely resembled that of the donor.Soil inoculation generally facilitates colonization by target plant and fungal communities, where establishment success of the former can be predicted by the latter, but the final outcome of succession is environmentally determined.

Nutritive value of forages and diets in some small-scale dairy farms in Kiambu County, Kenya in the short rains season

Sixteen selected small-scale dairy farms were investigated in Kiambu County (Kenya) during the short rains seasonto develop a snapshot of the types of rations fed, milk yields obtained and sources of fodder. On average farmers had1 ha of land and 2.2 lactating cows yielding 8.93 kg milk/cow/d with feed intake of 10.5 kg DM/d. Only 35% of feedconsumed was produced on farm. Boma Rhodes grass hay and green Napier grass were the main forage components(37.9 and 28.3% of total DM). Protein forages used were the herbaceous legumes lucerne and desmodium (19.9 and15.9% CP, respectively) and leguminous shrubs (Leucaena, Calliandra and Sesbania with 21.1% CP and 43.4%aNDFom, on average). Grasses had higher aNDFom digestibility (47.1%) than legumes (39.7%). Napier grass, BomaRhodes grass, lucerne and desmodium had fiber digestibility of 51.9, 48.6, 46.8 and 32.6%, respectively. The energyand protein balances (actual vs. requirements) of the cows were on average -19.3 and -16.4%, respectively, indicatingthat cows utilized body tissues to produce the levels of milk obtained. Mutiple correspondence analysis showed that amilk yield higher than 9.1 kg/d was associated with a level of Boma Rhodes grass &lt;5 kg DM/d, concentration of nonfibrous carbohydrates in the diet &gt;22.0% (DM basis), concentrate level &gt;2.63 kg/cow/d and CP% in the ration &gt;9.1%. To improve milk yields during this season farmers should harvest grass forage at a younger age, include leguminous forage in the diets and increase the level of concentrates fed. These strategies should be demonstrated on farms to show possible benefits.

Effects of land use and climate on carbon and nitrogen pool partitioning in European mountain grasslands

European mountain grasslands are increasingly affected by land-use changes and climate, which have been suggested to exert important controls on grassland carbon (C) and nitrogen (N) pools. However, so far there has been no synthetic study on whether and how land-use changes and climate interactively affect the partitioning of these pools amongst the different grassland compartments. We analyzed the partitioning of C and N pools of 36 European mountain grasslands differing in land-use and climate with respect to above- and belowground phytomass, litter and topsoil (top 23 cm). We found that a reduction of management intensity and the abandonment of hay meadows and pastures increased above-ground phytomass, root mass and litter as well as their respective C and N pools, concurrently decreasing the fractional contribution of the topsoil to the total organic carbon pool. These changes were strongly driven by the cessation of cutting and grazing, a shift in plant functional groups and a related reduction in litter quality. Across all grasslands studied, variation in the impact of land management on the topsoil N pool and C/N-ratio were mainly explained by soil clay content combined with pH. Across the grasslands, below-ground phytomass as well as phytomass- and litter C concentrations were inversely related to the mean annual temperature; furthermore, C/N-ratios of phytomass and litter increased with decreasing mean annual precipitation. Within the topsoil compartment, C concentrations decreased from colder to warmer sites, and increased with increasing precipitation. Climate generally influenced effects of land use on C and N pools mainly through mean annual temperature and less through mean annual precipitation. We conclude that site-specific conditions need to be considered for understanding the effects of land use and of current and future climate changes on grassland C and N pools.