Mixed Grass Research Articles

Growth performance of goats (Capra hircus L.) on forage legumes mixed with guinea grass (Megathyrsus maximus)

Proper feed optimization is vital for the health and growth of goats, with fodder quality being a central factor. This study evaluated the impact of feeding goats guinea grass mixed with various tree legumes on their growth and feed consumption. Nine upgraded goats were used for this research, divided equally among three treatment groups. Each treatment was repeated three times, with one goat per repetition. The experimental treatments included guinea grass paired with Gliricidia (T1), Indigofera (T2), or Ipil-ipil (T3). The results showed that the T2 (Guinea grass + Indigofera tinctoria) combination resulted in the highest feed intake at 29.94kg over five weeks, a finding significant with a p-value of 0.04. Nutrient analysis demonstrated a significant intake of crude protein for T2 with a p-value of 0.038. Moreover, T2 exhibited the most substantial total weight gain (3016.67g) and an average daily gain of 86.19g/day, with p-values of <0.001 and 0.013 respectively. In conclusion, the mix of Guinea grass and Indigofera tinctoria offers the best results in terms of feed intake and goat growth performance. Keywords: Goat feed optimization, guinea grass, Indigofera, Gliricidia, Leucaena

Формирование структурно-функциональной организации молодняков сосны обыкновенной (Pinus sylvestris L.) смешанного искусственно-естественного происхождения в условиях сосняков ягодникового и разнотравного Среднего Урала

Restoration of forests, the study of the processes of formation of their structure and productivity, is currently one of the most urgent tasks. The features of the formation of 12-year-old forest plantations and the concomitant natural regeneration of Scots pine (Pinus sylvestris L.) were studied under the conditions of berry pine forest and forb pine forest of the Middle Urals, on trial plots established in accordance with the existing requirements. For each Scotch pine (Pinus sylvestris L.) tree, the diameter at the middle height and height were measured, and the volume of the trunk in the bark was calculated. The rank distribution of trees was carried out by calculating their reduction numbers, determining the amplitude of the reduction numbers and subsequent distribution into 5 main classes. In the 12th year after planting, the survival rate in the berry pine forest was 47.0%, and in the forb pine forest - 35.3%. In the berry pine forest, taking into account the concomitant natural regeneration of Scots pine (Pinus sylvestris L.), a pine forest of artificial and natural origin is being formed, and in the forb pine forest, a pine forest of natural and artificial origin is being formed. The process of natural renewal of Scotch pine (Pinus sylvestris L.) took place over several years. Scots pine (Pinus sylvestris L.) trees of natural origin are 2-7 years younger in biological age than trees of artificial origin. Pine trees of artificial origin in the berry pine forest significantly exceed the average diameter at the middle of the height, height and trunk volume of the same trees in the forb pine forest. Pine trees of natural origin in the berry pine forest are significantly superior in average diameter at the middle of the height to trees in the forb pine forest, but they are significantly inferior to them in the average trunk height and practically do not differ in the average volume of the tree trunk. Trees of artificial origin in terms of diameter at the middle of the height, height and volume of the trunk significantly exceed trees of natural origin both in the berry pine forest and in the mixed grass pine forest. The distribution of trees by diameter and height in young forests of artificial and natural origin, both in the berry pine forest and in the forb pine forest, is characterized by a distribution close to normal. The distribution of trees of artificial and natural origin in the berry pine forest and the forb pine forest in terms of trunk volume is distinguished by left-sided asymmetry and sharpness. When distributed by rank height classes, a significant reduction in the level of variability of biometric indicators is provided. However, in natural young stands, a very high level of variability in stem volume in the bark remains. Both in artificial and natural young stands, the main (86.3-97.5%) stock of trunk wood in the bark falls on trees of I-III height classes. In the forb pine forest, artificial and natural young stands had almost the same reserve values, which confirms the formation of young pine stands of natural artificial origin. In the berry pine forest, birch renewal does not represent significant competition to pine. In the forb pine forest, birch creates serious competition for pine and, probably, the formation of deciduous-coniferous plantations and oppression of pine.

Inoculation of cold-adapted microbial consortium screened from alpine meadows promotes the growth of mixed grasses by changing soil properties and enzyme activity

The objective of this study was to investigate the effect of co-inoculation of three PGPR strains and inoculation ratio on the growth characteristics and soil properties of mixed grasses. In this study, we used 3 strains of PGPR for the material, which were Acinetobacter calcoaceticus called HMAJ1, Pseudomonas piscium called HMAJ5, and Pseudarthrobacter psychrotolerans called NCZ1, with nitrogen fixation and phosphorus solubilization ability. By mixing the bacteria in a different ratio, the effect of inoculating with a microbial consortium on the plant and soil properties of mixed grasses (Elymus nutans Griseb, Festuca sinensis, and Poa pratensis L.) was evaluated and the best microbial inoculants ratio was selected. The results showed that inoculating with a microbial consortium increased the soil organic carbon , available phosphorus, ammonium and nitrate nitrogen content, and the activities of soil alkaline phosphatase, sucrase, peroxidase, and urease, which promoted the plant height and biomass of mixed grasses. Pearson correlation analysis showed that plant characteristics were differently correlated with soil properties. Grey correlation analysis of plant biomass, soil properties, and soil enzyme activity revealed that T7 (HMAJ1:NCZ1 = 3:7) was the most effective in improving mixed-grasses biomass and soil quality. Our results indicated that the positive interaction of nitrogen-fixing bacteria with phosphorus-solubilizing strains may become a novel and effective bio-inoculant to achieve sustainable pulse productivity.

Does skin prick test response intensity predict symptom severity and efficacy of subcutaneous immunotherapy in allergic rhinitis?

To investigate the effect of response intensity of allergen skin prick test (SPT) on symptom severity and long-term efficacy of dust mite subcutaneous immunotherapy (SCIT) in allergic rhinitis (AR). AR Patients diagnosed with dust mite allergy and completed 3years of SCIT were collected and classified into three groups: grade 2 (SPT of + +), grade 3 (SPT of + + +) and grade 4 (SPT of + + + +). Comparisons between groups were performed to examine the associations of SPT categories and symptom severity and the long-term efficacy of SCIT in AR. 181 AR patients were included. There was no significant difference in the baseline TNSS, SMS, RQLQ and VAS, and particularly to symptom severity grading among three SPT grade groups (P > 0.05). The moderate-severe AR was more likely to be smoking and accompany with asthma and had higher prevalence of sensitization to cockroach, mixed grass and tree pollen than mild AR (P < 0.05). Prevalence of sensitization to cockroach, mixed grass, ragweed and animal dander was increased in AR patients with asthma and allergic conjunctivitis (P < 0.05). Furthermore, after 3years of SCIT, no statistical differences in TNSS, SMS, RQLQ, VAS and long-term efficacy were observed among the three SPT grade groups (P > 0.05). Similarly, long-term outcomes of patients with different SPT grades did not differ among different clinical characteristics and different efficacy determination criteria (P > 0.05). The SPT response intensity cannot be used as an objective evaluation index for symptom severity and the long-term efficacy of SCIT in AR patients.

Efficacy of S-metolachlor + glyphosate for Weed Control in Different Levels of Eucalyptus Straw

The occurrence of weeds in eucalyptus plantations can cause losses in productivity. Chemical control is widely used, but the efficiency of herbicides depends on management and environmental factors. This study aims to evaluate the efficiency of S-metolachlor + glyphosate in the control of grasses in different densities of eucalyptus straw and with simulated rainfall after application of the product. The experiment was conducted in a randomized block design, factorial, with four replications. The first factor represented 0; 1.06 + 0.79 e 2.12 + 1.59 kg i.a. ha−1 of the commercial dose of S-metolachlor + glyphosate, the second 0; 5 and 10 tons ha−1 of straw and, the third 25 and 50 mm of water depth applied in soil with a mix of grasses previously sowed. The evaluations carried out were fresh mass, dry mass, and visual analysis of the control percentage. The fresh and dry mass and the grasses’ dry mass/water ratio decreased with increasing herbicide dosage and straw density. The treatments without straw and with the herbicide application had the highest percentages of control, the highest in the dosage of 2.12 + 1.59 kg i.a. ha−1 of S-metolachlor + glyphosate. Applying different water depths (25 mm or 50 mm) did not influence the control. In conclusion, it was observed that the isolated straw promoted the control of grasses. However, in treatments that included straw and herbicide, there was a decrease in the efficiency of the product, which suggests an antagonism between the vegetation cover and S-metolachlor + glyphosate.

Fractionation of mixed grass and clover stands using a leaf stripper

AbstractLeys are an important part of northern European livestock production, particularly for ruminants since monogastric animals are limited in their ability to digest the fibres of the forage. Crop fractionation methods are a promising option to make forages more beneficial for monogastric animals and decrease the amount of imported protein feed. A leaf stripping harvesting technique was evaluated at Röbäcksdalen in northern Sweden in mixed grass‐clover leys over 2 years. The PremAlfa Mini leaf stripper (Trust'ing‐Alf'ing, Nantes, France) worked well in mixed stands, harvesting on average a third of the available forage biomass, primarily in the form of leaves and soft stems from the clover plants. It proved successful in producing a forage fraction that had a significantly higher crude protein (CP) concentration (+39.1%) and lower neutral detergent fibre (aNDFom) concentration (−21.4%) than the pre‐harvest mixed sward (all significant at p &lt; .05 level). Due to the remaining high level of aNDFom in the leaf stripper fraction, it is more suited for use as an energy source for monogastrics rather than as a protein supplement. Alternatively, the leaf stripper fraction could be used to increase digestibility and CP content in the feed rations of high producing dairy cows.

Ecosystem multifunctionality and soil microbial communities in response to ecological restoration in an alpine degraded grassland.

Linkages between microbial communities and multiple ecosystem functions are context-dependent. However, the impacts of different restoration measures on microbial communities and ecosystem functioning remain unclear. Here, a 14-year long-term experiment was conducted using three restoration modes: planting mixed grasses (MG), planting shrub with Salix cupularis alone (SA), and planting shrub with Salix cupularis plus planting mixed grasses (SG), with an extremely degraded grassland serving as the control (CK). Our objective was to investigate how ecosystem multifunctionality and microbial communities (diversity, composition, and co-occurrence networks) respond to different restoration modes. Our results indicated that most of individual functions (i.e., soil nutrient contents, enzyme activities, and microbial biomass) in the SG treatment were significantly higher than in the CK treatment, and even higher than MG and SA treatments. Compared with the CK treatment, treatments MG, SA, and SG significantly increased the multifunctionality index on average by 0.57, 0.23 and 0.76, respectively. Random forest modeling showed that the alpha-diversity and composition of bacterial communities, rather than fungal communities, drove the ecosystem multifunctionality. Moreover, we found that both the MG and SG treatments significantly improved bacterial network stability, which exhabited stronger correlations with ecosystem multifunctionality compared to fungal network stability. In summary, this study demonstrates that planting shrub and grasses altogether is a promising restoration mode that can enhance ecosystem multifunctionality and improve microbial diversity and stability in the alpine degraded grassland.

Single and Multispecies Cover Crop Effects on Corn Production and Economic Returns

AbstractThe adoption of cover crops (CCs) has gained popularity in the continuous corn (Zea mays L.) production system due to their multiple benefits including scavenging or fixing nitrogen (N) in the soil. However, a CC's ability to develop early cover, scavenge N, and provide N to the following cash crop is species‐dependent and affected by environment. A field study was conducted in three diverse environments to determine growth characteristics of nine CC treatments (i.e., monocultures or mixes of grasses, legumes, and brassica), and their effect on the following corn crop was compared to no cover crop treatment (noCC). Cover crops significantly differed for above‐ground biomass, plant tissue carbon (C) and N concentrations, carbon to nitrogen ratio (C/N), and total N uptake (TNU). Among monocultures, grasses had the highest biomass and C/N ratio, and legumes had the highest N concentrations and TNU. Corn grain yield was highest following radish, whereas lowest corn yield was found following cereal rye + crimson clover mix in environment 1. Cover crops varied for C/N ratios in all three environments, but only affected corn plant height (PH) and grain yield in one environment. Cover crops belonging to the same species also exhibit different responses for characteristics measured, depending upon the environment. The expected returns were also variable, especially in CC mixes. The study provides valuable information on the species‐specific functionality of CCs in continuous corn under variable environmental conditions. The information will benefit future studies to explore a high diversity mixture of CCs that may outperform across all three environments.

Influence of irrigation and supplementation on performance and ingestive behavior of beef cattle on mixed grass pastures

Influence of irrigation and supplementation on performance and ingestive behavior of beef cattle on mixed grass pastures

Evaluation of the toxicity of forb hay by biotesting method using &lt;em&gt;Paramecium caudatum&lt;/em&gt;

Today, the topic of assessing the toxicity of feed is relevant. In Russia, the production of environmentally friendly products is one of the priority areas in agriculture. Eating feed contaminated with industrial waste, pesticides, mycotoxins by domestic and farm animals can adversely affect their health. In this work, the quality of mixed grass hay was assessed by biotesting using Paramecium caudatum test organisms. The essence of the method lies in the preparation of aqueous extracts and aqueous solutions of acetone extracts of the sample and the effect of the obtained extracts on Paramecium caudatum. This method is convenient because you can quickly get the necessary results regarding the toxicity of the sample. The study was carried out on the basis of the laboratory of the Department of Biochemistry and Physiology of the St. Petersburg State University of Veterinary Medicine. Less than 50% of Paramecium caudatum survived in an aqueous extract and an aqueous solution of an acetone extract, the toxicity of the sample was established according to GOST 31674- 2012 «Feeds, compound feeds, material for compound feeds. Methods for the determination of common toxicity»

Improving acidic sandy soil properties for plant growth with dam reservoir sediments in the face of soaring fertiliser prices

Recent actions aimed at creating an environmentally sustainable economy, as well as very high inorganic fertiliser prices, have begun a ‘renaissance’ of alternative fertilisation. It includes utilisation of dam reservoir (DR) sediments. The aim of our study was to evaluate the agricultural value of non-toxic material to be dredged from a dam reservoir in the face of changing mineral fertiliser prices. The quality of sediments was established based on pot experiment: four different sediment dosages (5 %, 10 %, 20 %, 40 %) and three plants in rotation (maize, mustard and grass mix) were tested. Application of DR sediments into sandy soil improved its texture (depending on dose 4–31 % less sand, 50–412 % more silt and 40–70 % more clay) and sorption properties, increased pH (the soil was acidic). The content of total organic carbon increased 1.4–4.3 times, total nitrogen (N) 1.4–4.7 times, ammonium nitrogen 1.3–5.2 times, nitrate nitrogen 1.7–11.8 times, total phosphorus (P) ∼1.4 times and available phosphorus ∼2.0; most changes were statistically significant. Yield of all three plants increased significantly correspondingly to the sediment application. It shows that DR sediments might be a good alternative to chemical fertilisers. Since the catchment of the analysed reservoir is mostly agricultural, N and P compounds accumulated in sediments originated from farming. Therefore, using DR sediments as fertilisers closes the cycle of these elements; N and P compounds can be used by plants. Additionally, this alternative fertiliser is cheap – since the analysed reservoir has to be dredged, large amounts of sediments will be obtained as a ‘side-effect’ of this process. Agricultural application of this nutrient-rich material would transform sediments from waste into a resource. Recent steep increase of mineral fertilisers prices – in Poland, the prices in 2022 were 2–3 times higher than in 2018 – showed that we have to diversify fertiliser sources. Low cost, ecological sustainability and good physical and chemical properties make DR sediments, if not a substitute, a good addition to the traditional methods of agricultural fertilization.

The spatial placement of the steppe marmot (&lt;i&gt;Marmota bobak&lt;/i&gt; Muller, 1776) in the Pervomaisky District of the Orenburg Region

This paper deals with the spatial placement of the marmot in the Pervomaisky District of the Orenburg Region within the steppe zone of the Southern Urals. The spatial structure of steppe marmot settlements is characterized by a typical ravine-girder (ribbon) type of territorial distribution of family groups and is determined mainly by the presence of habitable areas. The settlements of marmots on this territory are located mainly along ravines and gullies of small rivers and streams, and to a lesser extent on agricultural land. It has been revealed that marmots prefer to settle on the gentle slopes of the southern exposure mainly in the middle part of the gullies occupied by fescue-feather grass steppe, sagebrush-grass steppe and mixed grass communities used as pastures. The results of the research show that the burrow mound of the marmot, located in different parts of the studied territory and having different degrees of anthropogenic load, differ both in height and diameter of the burrows, and the distance between the burrows. At the same time, there is a clear, direct dependence of the degree of anthropogenic impact on the aggregation of marmot settlements. A significant factor in the distribution of marmot settlements and its spatial structure of populations is the degree of impact on the territory of the anthropogenic press.

Comparison of alternative neutral detergent fiber methods to the AOAC definitive method

Neutral detergent fiber (NDF) is the most commonly reported metric for fiber in dairy cattle nutrition. An empirical method, NDF is defined by the procedure used to measure it. The current definitive method for NDF treated with amylase (aNDF) is AOAC Official Method 2002.04 performed on dried samples ground through the 1-mm screen of a cutting mill with refluxing and then filtration through Gooch crucibles without (AOAC-; reference method) or with (AOAC+) a glass fiber filter filtration aid. Other methods in use include grinding materials through the 1-mm screen of an abrasion mill, using filtration through a Buchner funnel with a glass fiber filter (Buch), and use of the ANKOM system (ANKOM Technology, Macedon, NY) that simultaneously extracts and filters samples through filter bags with larger (F57) or smaller (F58) particle size retentions. Our objective was to compare the AOAC and alternative methods using samples ground through the 1-mm screens of cutting or abrasion mills. Materials analyzed were 2 alfalfa silages, 2 corn silages, dry ground and high-moisture corn grains, mixed grass hay, ryegrass silage, soybean hulls, calf starter, and sugar beet pulp. Samples were run in duplicate in replicate analytical runs performed on different days by experienced technicians. Compared with cutting mill-ground samples, the aNDF% of dry matter results from abrasion mill-ground samples were or tended to be lower for 8 of 11 samples. Method affected aNDF% results for all materials, with method × grind interactions for 6 of 11 samples. For ash-free aNDF% assessed with cutting mill-ground materials, a priori selected contrasts showed that the number of materials for which methods differed or tended to differ from the AOAC methods were 4 (Buch), 8 (F57), and 3 (F58); and 3 for AOAC- versus AOAC+. However, statistically different does not necessarily mean substantially different. For a given feed and grind, a positive value for the absolute difference between the AOAC- mean and an alternative method mean minus 2 times the standard deviation of AOAC- suggests that values for the alternative method fall outside of the range of results likely to be observed for the reference method. The number of observed positive values for materials processed with cutting and abrasion mills, respectively, were 0 and 2 (AOAC+); 2 and 2 (Buch); 8 and 10 (F57); 4 and 7 (F58); and 0 and 4 (AOAC-). With the materials tested, methods in order of agreement with the reference method were Buch, F58, and F57, which often gave lower values. The AOAC+ gave results similar to AOAC-, substantiating it as an allowed modification of AOAC-. Best agreement between the reference method and variant NDF methods was achieved with the 1-mm screen cutting mill grind. The 1-mm abrasion mill grind produced more aNDF% results that were lower than the reference method but with fewer differences when filter particle retention size was smaller. The use of filters that retain finer particles could be explored to improve comparability of variant NDF methods and grinds. Further evaluation with an expanded set of materials is warranted.

Recovery of dry mixed grass prairie well sites 15 years after reclamation

In the mixed grass prairie region of North America, well sites and their associated infrastructure have many ecological effects, including changes to soil physical, chemical and biological properties, loss of vegetation cover, altered plant species composition and habitat fragmentation. Reclamation of disturbed grassland is a challenge faced by many rangeland and conservation managers. The objective of this research was to examine the effect of time on reclaimed grassland well site soil properties and plant communities in southern Alberta. Seeding with three mixes of different numbers of species and proportions of native wheatgrasses (Triticeae tribe) was compared to natural recovery and undisturbed prairie after 15 years. Chernozemic soil was more similar to undisturbed prairie than Solonetzic soil, where soil chemical properties and plant species composition were less resilient following disturbance in some revegetation treatments. All reclaimed treatments had significantly lower soil organic matter, organic carbon and total nitrogen than undisturbed prairie. Vegetation cover and species richness in reclaimed sites did not usually differ from undisturbed prairie. An increase in the proportion of native wheatgrass cultivars in a seed mix did not result in a community dominated by them. Multivariate analysis showed species compositional differences in seeded and natural recovery relative to undisturbed prairie on Solonetzic soil, with no difference on Chernozemic soil except with the dominant wheatgrass seed mix. Thus recovery may require longer than 15 years for Solonetzic soil and revegetation with a dominant wheatgrass seed mix. Presence of early to late successional species indicated natural recovery could be a potential option for mixed grass prairie well site reclamation.

Aeroallergens sensitization pattern in atopic patients in Qatar: A retrospective study.

Allergic respiratory diseases (allergic rhinitis and asthma) are major health problems with high prevalence causing significant patient morbidity as well as an economic burden (1). Sensitization to inhaled allergens is a major factor in the pathogenesis of allergic respiratory diseases (2). This study aims to determine the commonest aeroallergen sensitization in patients with allergic symptoms who attended an Adult Allergy Clinic in Qatar. This retrospective study reviewed the skin prick test results database of 20 aeroallergens performed between January 1st to December 31st, 2022, at an Adult Allergy clinic in Qatar. Based on skin test results, the most prevalent aeroallergens were determined. A total of 554 patients (43% males, 57% females), aged between 12-87 years, 36±13.8 (mean ± SD), underwent skin prick test, of which 378 patients (68%) had positive results. There were no significant sex differences in the frequency of atopy (males: 60% versus females: 65% p= .076). Of the total 554 patients, 62% were diagnosed with Allergic rhinitis, 19% with non-allergic rhinitis, 32% with asthma, 6.7% with chronic urticaria, and 6.5% with atopic dermatitis. The frequency of sensitivity to aeroallergens was Dermatophagoides pteronyssinus 49.5%, Dermatophagoides farina 38.6%, Cat 37.3%, American Cockroach 25.9%, Russian thistle 24%, German cockroach 20%, Rough pigweed 19%, Bermuda grass 11%, and 8% to seven grass mix. 61 % were sensitized to indoor aeroallergens and 31% to different pollens (outdoor). Of the 378 patients who were sensitized, 145 patients (38%) were monosensitized, and 233 (62%) were polysensitized (≥2 allergens). There were no significant differences in the frequency of polysensitization between males and females (M:F: 1:1, p=0.938). Insects (house dust mites and cockroaches) and animal protein (cat hair) were the most prevalent positive aeroallergen by skin tests. However, weed, tree pollens (Russian thistle, Rough pigweed, Mesquite tree), and grass pollens (Bermuda and seven grass mix) were also positive for a minority of patients. 62% of patients were polysensitized to aeroallergens.

112 Effects of storage-handling methods on nutrient analysis of mixed-grass pasture samples

Forage should be the basis of any equine diet, even for those with insulin dysregulation (ID). Fresh and preserved forage low in nonstructural carbohydrates (NSC) is recommended for ID animals, indicating the need for an accurate forage analysis. It remains to be fully understood how handling fresh forage samples pre-analysis impacts nutrient values. The objectives of this study were to compare 5 pasture sample storage-handling methods, analyzed after 24h and 1wk, on various nutrients including crude protein (CP), water soluble carbohydrates (WSC), ethanol soluble carbohydrates (ESC), starch and NSC. In October 2022, forage samples were manually harvested to ground height between 0800 and 0900 from a mixed-grass pasture after a rest period. Subsamples were mixed to create triplicate samples for analysis at both time periods (24h vs 1 wk) and the following 5 storage-handling methods: microwave-oven (70s then stored at −20°C; MO), room temperature (RT), 3°C, −20°C, and −80°C, totaling 30 samples. All forage samples were shipped on ice to a commercial laboratory for wet chemistry and NIR analysis (Equi-Analytical, Ithaca, NY). Data were analyzed using 2-way ANOVAs in JMP with fixed effects of storage method, time and storage by time interactions as well as storage-handling method by laboratory analysis method and method by storage interactions.Statistical significance was declared at P ≤ 0.05. All data reported are from wet chemistry analysis as there were no significant differences between the 2 analysis techniques. Storage by time interactions were statistically different for some nutrients measured from the mixed grass when stored at RT. Specifically, the WSC (9.2 ± 0.4% DM vs. 5.4 ± 0.9% DM; P = 0.009) and ESC (5.4 ± 0.4% DM vs. 3.6 ± 0.6% DM; P = 0.001) content decreased from 24h compared with 1wk. The remaining storage-handling methods of MO, 3°C, −20°C, and −80°C, however, showed no statistical differences across time for WSC, Starch or NSC indicating these methods were appropriate for storing forage for this time. A decrease in CP content from 24h compared with 1wk was, however, shown when stored at −80°C (12.7 ± 0.6% DM vs. 11.2 ± 0.3% DM; P = 0.02), yet no other statistical differences in CP were detected. These results demonstrate that samples kept at RT or −80°C for one week before nutrient analysis may not accurately represent the nutrient content of the forage. Storage-handling method and time did affect the nutrient content of fresh forage thus, samples should be either immediately dried, kept at 3°C, or frozen (−20°C) preceding analysis.

155 Survey of equine veterinarians: Part 1—Hay selection and evaluation

Few nutrition-related surveys of equine veterinarians have been conducted. This survey investigated the perspectives of veterinarians on selecting and evaluating hay for horses. A survey link (Qualtrics, Provo, UT) was sent to members of Kentucky Association of Equine Practitioners and distributed by equine practices located in Lexington, KY. Descriptive and inferential statistics were performed in SPSS V28. There were 41 responses with 34 completed surveys. The majority of veterinarians (93%) worked in equine-specialized practices (>90% equine), with the main practice areas relating to breeding (44%), performance (12%), recreational horses (2%), or a combination of equine specializations (42%). Veterinarians were confident in identifying hay types (78% very confident or confident) and evaluating hay quality based on sensory characteristics such as color and smell (73.2% very confident or confident), but only 41.5% were very confident or confident in evaluating hay quality based on forage analysis. Stage of maturity (52%) and texture (29%) were most selected as characteristics used to evaluate hay quality. Fiber (neutral-detergent fiber or crude fiber) was reported by 84% of respondents as the most useful chemical component to evaluate digestibility. Most veterinarians (85.3%) indicated that educational materials on selecting hay for differenthorse types, sensory evaluation of hay, and interpreting a forage analysis would be useful to share with clients. When asked to rank the likelihood of recommending certain hay types for different classes of horses, alfalfa hay and mixed alfalfa grass hay were less likely to be recommended for sedentary horses compared with breeding and growing and performance horses (P < 0.001). Veterinarians in breeding farm practices tended to be less likely to recommend cool-season grass hays for breeding and growing horses compared with veterinarians in other practice types (P = 0.09). Hay sampling and analysis services were not routinely offered to clients, but 50% of veterinarians had submitted a sample for analysis, with the most selected reason being to evaluate nonstructural carbohydrates (35%). When asked where they would refer clients requesting this service, 11% of veterinarians were unsure, while 67% selected county extension agent and 19% commercial lab. This group of veterinarians displayed understanding of key principles of selecting and evaluating hay for horses. This preliminary survey provides valuable information regarding nutrition-based interactions between veterinarians and their clients that can be used to develop educational materials.

105 Botanical composition, yield, horse preference, and forage and soil nutrient values of grass pastures treated with different soil amendments

Forage is the foundation of a horse's diet, therefore, pasture management is critical to improve horse health and pasture productivity. The objective of this study was to evaluate botanical composition, horse preference, yield, and forage and soil nutrient values of pasture treated with horse manure, horse compost, commercial urea fertilizer, and a no amendment control. Researchers hypothesized soil amendments would increase soil nutrients and yield with minimal effects on botanical composition, preference and forage nutrient value. Replicated (n = 3) plots of established cool-season mixed grass pasture were 3 × 6 m and located in St. Paul, Minnesota. The soil was a Waukegan silt loam with a pH of 6.4 and 47 g kg–1 organic matter. Urea was applied based on initial soil test recommendations, 0.64 cm of compost was applied based on common recommendations, and manure was applied at a rate to represent horse manure deposition in May 2022. Sample collection and grazing periods occurred in May, June, July, August, and October 2022, each over a 2-d period. Botanical composition, average forage height and maturity, soil samples, forage samples, and forage yield were taken immediately before grazing. Horses were allowed to graze all plots for 4 h with preference visuallyassessed at 2- and 4 h post-grazing based on percent removal. Data were analyzed as a randomized complete block design using PROC MIXED in SAS with significance set at P ≤ 0.05. Season-long yield ranged from 2,690 to 3,363 kg DM ha-1 and did not differ across treatments (P > 0.05). Botanical composition differed across treatments with the control having the most weeds (32%) and the least amount of grass (62%) while manure treatments resulted in the most bare ground (11%; P ≤ 0.05). The soil nutrients magnesium and phosphate were highest in compost-treated plots and nitrate-nitrogen and sodium were highest in manure-treated plots (P ≤ 0.05). Forage nutrient content did not differ across treatments (P > 0.05). Horses did not prefer pasture treated with manure and only 15 and 33% of forage was consumed after 2 and 4 h, respectively (P ≤ 0.001). All other treatments averaged 53 and 78% removal after 2 and 4 h, respectively. Based on differences observed in botanical composition and horse preference, commercial fertilizer and compost appear to be the most beneficial soil amendments for horse pastures.

61 Rapid changes in fecal pH in horses fed either a mixed diet or pasture

Horses need to maintain a stable microbial population to support proper digestion and nutrient absorption, and most changes in feeding are done over a 5–7-d period to minimize digestive upset. A healthy gastrointestinal system typically has a pH of 6.5–7.0, and fiber fermenting bacteria like Streptococcus spp and Lactobacillus spp create an optimal environment for digestion and useable energy production. The objective of this study was to compare spring pasture grazing to a mixed diet to see the influence of diet on fecal pH within a short period of time. Nine mature geldings were used to measure the changes in fecal pH between the 2 diets for a period of 4 d. Horses were assigned to a control group (n = 5) maintained on pasture only, and a restricted group (n = 4) on a dry lot with access to mixed grass hay and a textured concentrate. Approximately 200g of feces were collected from each horse to produce 30mL of fecal liquid. The change in fecal pH, which was defined as the difference in the pH levels between d 4 and d 0 (baseline), was calculated for each horse. The averagechange in pH for the mixed diet group was 0.312 (standard deviation (SD) = 0.295), while the average change in pH for the pasture group was −0.678 (Standard deviation (SD) = 0.227). Since the size of each treatment group was small, the assumption of normality required for the independent measures t-test could not be reliably assessed. Therefore, the non-parametric Mann-Whitney U test was used, which showed that the change in fecal pH was significantly larger in the mixed diet group (Median (Mdn) = +0.295) than in the pasture group (Mdn = - 0.700), U = 20, P = 0.016, using an exact sampling distribution for U. In conclusion, horses on a dry lot fed a mixed diet had an increase in fecal pH compared with a decrease in fecal pH for pastured horses, with both changes occurring within 4 d. No horses exhibited any digestive or behavioral problems, which suggests that bacterial population and activity changes may safely occur more quickly than previously thought.

70 Ahiflower (Buglosoides Arvensis) oil supplementation alters whole blood and muscle fatty acid profile in mature horses

The omega-3 (n-3) profile of common plant-based ingredients are derived from α-linolenic acid (ALA). Previous research has indicated that horses lack the ability to convert ALA or other short-chain polyunsaturated fatty acids (SC-PUFA) into the biologically relevant docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Ahiflower (Buglossoides Arvensis) oil is a novel plant-based source of omega-3 fatty acids derived from n-3 stearidonic acid (SDA), and gamma-linolenic acid (GLA), an omega-6 fatty acid (see Table 1 for fatty acid profile). The objective of this trial was to evaluate how supplementation of Ahiflower oil to horses would alter whole blood and muscle fatty acid composition. Mature Quarter Horses (n = 20) were balanced by age, BW, and BCS and assigned to one of 4 treatment groups. LOW (n = 5; BW = 507.12 ± 2.3kg; BCS = 5.4 ± 0.3) was offered 30mL/day of Ahiflower oil. HIGH (n = 5; BW = 517.45 ± 4.5kg; BCS = 5.7 ± 0.1) was offered 60mL/day of Ahiflower oil. FLAX (n = 5; BW = 497.25 ± 3.5kg; BCS = 6.1 ± 0.7) was offered a flaxseed pellet (CP = 15.42%, Total omega-3 = 3.75%) formulated to provide the same amount of total omega-3′s as LOW was offered. PAST (n = 5; BW = 508.14 ± 3.6kg; BCS = 5.2 ± 0.6) was allowed free-choice access to mixed grass pasture (CP = 16.0%, Total omega-3 = 0.79%). All horses were offered 1.81kg/d of Purina® Strategy GX® (CP = 14.24%, Total omega-3 = 0.44%) daily. LOW, HIGH, and FLAX were housed in drylots by treatment group and were offered 2.0% BW as Timothy grass hay (CP = 10.10%, Total omega-3 = 0.35%). On d 0, 30, and 60 blood samples were collected along with a mid-gluteal muscle sample (∼1g). Samples were analyzed for fatty acid profile via LC-HPLC (UF ATCL).Data were analyzed via ANOVA (SAS 9.4). Horses in the LOW group had a 12.5% increase in total omega-3, while horses in HIGH had a 40.1% increase. Similar differences were observed for EPA (LOW = 19.2%; HIGH = 40.1%), and GLA (LOW = 60.1%; HIGH = 167%). Horses in HIGH had a greater increase from baseline in muscle EPA + DHA compared with all other groups (250%). All differences were significant at P < 0.05. Taken together these data indicate that horses had the ability to convert the PUFA's in Ahiflower oil into EPA. Increased EPA in whole blood and muscle tissue potentially allows for increased production of anti-inflammatory eicosanoids and prostaglandins. Further research is necessary to elucidate the mechanism by which this conversion occurs.