Suitability of biocompost as a bedding material for stabled horses: respiratory hygiene and management practicalities

REASONS FOR PERFORMING STUDY: Bedding material in stables has an important influence on air hygiene and information on the suitability of biocompost and wood shavings is incomplete. OBJECTIVES: To compare the suitability and benefit of biocompost and wood shavings as bedding in horse stables and to determine key air factors for the evaluation of the potential impact of these materials on respiratory health. METHODS: The study was conducted in a naturally ventilated stable with 4 horses. Air hygiene parameters were measured 24 h/day for 7 days with each bedding type: ammonia (NH3), inhalable and respirable dust, endotoxins, colony forming units (CFU) of total mesophilic bacteria, fungi, actinomycetes and thermophilic actinomycetes. Both bedding materials were analysed for general chemical composition, particle size distribution and natural microbial content. The animals' behaviour was monitored by video cameras, and their health and cleanliness status determined by clinical and visual examination. RESULTS: Concentrations of NH3, dust, endoxins and fungi were significantly higher during the monitoring period with wood shavings than with biocompost. In contrast concentrations of mesophilic bacteria, mesophilic actinomycetes and thermophilic actinomycetes microbial pollutants were highest with biocompost. The water content of bulk biocompost was considerably higher than that of wood shavings. Particles < or = 0.4 mm were not detectable in bulk wood shavings. The concentration of thermophilic actinomycetes by weight in raw biocompost was 639 times higher than in raw wood shavings. No significant differences were observed in the time spent by the horses lying down. The biocompost material tended to adhere more intensively to the animals' hair coat. Horses showed no clinical signs indicating any adverse effects of the biocompost material during the trials. CONCLUSIONS: Biocompost cannot be recommended as bedding material for horses in stables, because the concentration of thermophilic actinomycetes and other agents that elicit and maintain recurrent airway obstructions was significantly higher with biocompost than with wood shavings. To ensure the well-being of horses, any new bedding material must be tested very carefully before it is introduced to the market.     

Effects of Different Bedding Materials on the Behavior of Horses Housed in Single Stalls

The effects of three different bedding materials (straw, wood shavings, and straw pellets) on the behavior of six warmblood horses (four mares, two of them with foals) housed in single stalls were analyzed. Each material was used for 2 weeks in three consecutive runs. The behavior of the horses was videotaped and analyzed on the first and last 3 days for each bedding alternative in the last of the three runs. The time budgets for the behaviors including standing, eating, lying, occupation with bedding material, and other were generated. Compared with straw pellets and wood shavings, the application of straw bedding led to a significantly higher frequency and longer duration of occupation with bedding material and in turn, shorter fractions of standing and other behaviors. The total duration of lying was significantly longer on straw than on straw pellets. Straw pellets resulted in the least mean recumbency duration per occurrence of this behavior. Because occupation is one of the important functions that bedding material is supposed to fulfill, we concluded that in regard to horse behavior, straw bedding was the best among the three materials analyzed. Further investigations with a more homogeneous group of probands are necessary to verify the observed behavioral reactions.     

Effects of bedding type on compost quality of equine stall waste: implications for small horse farms

Our objective in this study is to compare 4 of the most common bedding materials used by equine operations on the chemical and physical characteristics of composted equine stall waste. Twelve Standardbred horses were adapted to the barn and surrounding environment for 2 wk before the start of the study. Groups of 3 horses were bedded on 1 of 4 different bedding types (wood shavings, pelletized wood materials, long straw, and pelletized straw) for 16 h per day for 18 d. Stalls were cleaned by trained staff daily, and all contents removed were weighed and stored separately by bedding material on a level covered concrete pad for the duration of the study. Compost piles were constructed using 3 replicate piles of each bedding type in a randomized complete block design. Each pile was equipped with a temperature sensor and data logger. Water was added and piles were turned weekly throughout the 100-d compost process. Initial and final samples were taken, dried, and analyzed for DM mass, OM, inorganic nitrogen (nitrate-N and ammonium-N), electrical conductivity, and soluble (plant-available) nutrients. Data were analyzed using the GLM procedure, and means were separated using Fischer's protected LSD test (P < 0.05). No significant temperature differences were observed among the bedding materials. The composting process resulted in significant reductions (P < 0.05) in DM mass for each of the 4 bedding materials. The composting process resulted in significant reductions (P < 0.05) in OM and C:N ratio for all 4 bedding materials. The composted long straw material had greater concentrations of total Kjeldahl nitrogen (P < 0.05), nitrate-N (P < 0.05), and ammonium-N (P < 0.05) than the composted wood shavings. This study demonstrated that incorporating a simple aerobic composting system may greatly reduce the overall volume of manure and yield a material that is beneficial for land application in pasture-based systems. The straw-based materials may be better suited for composting and subsequent land application; however, factors such as suitability of the bedding material for equine use, material cost, labor, and availability must be considered when selecting a bedding material.     

The influence of bedding on the time horses spend recumbent

To determine if bedding has any influence on the time horses spend recumbent, 8 horses kept on straw and 8 kept on wood shavings were observed from 10:00 to 5:30 for two successive nights. Observations were conducted using time-lapse video recordings. Lying down and rising behavior, as well as frequency and duration of bouts spent in lateral and sternal recumbency, was registered. The results showed that horses on straw were lying in lateral recumbency three times longer than horses on shavings (P < .001), whereas the time horses spent in sternal recumbency did not differ. The longest period of noninterrupted lateral recumbency was longer for horses on straw than for those on shavings. Because horses must lie down, preferably in lateral recumbency, to achieve paradoxical sleep, the reduced time spent in lateral recumbency in horses on wood shavings may affect their welfare and performance. Independent of the bedding, we further observed that, as the horses got up from recumbency, most of them made attempts to roll over before rising. This behavior appeared to be caused by some difficulty in rising, possibly due to the box size, and might have a connection with the fact that horses sometimes get stuck against the box wall.

Introduction

Many riding horses spend the majority of their life in an artificial environment. Horse owners keep their horses under certain conditions because of tradition, because they want to make the horse feel comfortable from a human point of view, or to reduce the amount of work involved in horse husbandry. Often the choice of bedding substrate is made from a subjective point of view without assessing both short-term and long-term effects of the bedding. Part of the reason is that only few studies have analyzed horses' preferences for different bedding substrates and their effect on the time horses spend recumbent. In one study comparing straw and wood shavings, no significant preference was found.[1] In another study comparing plastic, wheat straw, and wood shavings, the time horses spent standing, sleeping, or lying down was not affected significantly by the bedding substrates. [2] Mills et al [3] found that horses, given a choice between straw and wood shavings, spent significantly more time on straw. Whereas the substrates had no significant effect on behaviors such as eating, lying, and standing alert, horses spent more time performing bedding-directed behaviors on straw but more time dozing on shavings. Finally, it has been reported that the use of nonstraw bedding may increase the risk of abnormal behaviors such as weaving. [4]As far as bedding properties are concerned, Airaksinen et al[5] concluded that air quality in the stable and utilization of manure can be improved by selecting a good bedding material. According to Reed and Redhead, [6] both straw and shavings are economical and easy to obtain, and they make a bright, comfortable bed. Straw bales are convenient to store, but may be eaten by the horse, are labor intensive, and may be dusty or contain fungal spores. Wood shavings are not eaten by the horse and are good for respiratory problems but need to be kept very clean because they are porous. In addition, they are not as warm as straw because they do not trap air the way straw does.Electroencephalographic (EEG) studies in cats have demonstrated that sleep can be divided into two stages of differing electrocorticographic (EcoG) patterns, ie, slow-wave-sleep (SWS) and paradoxical sleep (PS).[7] During PS, bursts of rapid eye movements (REM) can be seen at irregular intervals. [8] In humans, dreaming occurs during this stage. [9 and 10] Horses are able to sleep while standing, [11] but in this position they only go into SWS. [14, 15 and 16] During PS there is a complete abolition of muscular tone of antigravity muscles and of neck muscles, as shown in cats. [17] In horses, there is a gradual loss of muscular tone until the middle of the recorded SWS period, whence it decreases to a negligible amount during PS. [15] Consequently, muscular tone disappears entirely at the onset of PS. [18] Horses are unable to complete a sleeping cycle without lying down to enter PS. [8, 19 and 20] They normally fall asleep while standing and, when they feel confident about their environment, lie down in sternocostal recumbency. [8] Thereafter, they proceed to lateral recumbency and enter PS. [14 and 19] Dallaire and Ruckebusch [18] demonstrated that the SWS state was infrequent in the standing animal and most often occurred during sternocostal recumbency with the head resting or not on the ground. PS occurred in both sternocostal and lateral recumbency, although the animal frequently had to readjust its position into sternocostal recumbency due to the disappearance of neck muscular tone.The sleep pattern of horses depends on many circumstances, such as age,[21, 22 and 23] diet, [16] and familiarity with the environment. When horses are put outdoors it may take some days before they lie down. If one horse that is familiar with the environment lies down, the others usually follow. [8 and 13] Dallaire and Ruckebusch [16] subjected three horses to a four-day period of perceptual (visual and auditive) deprivation. After this period total sleep time increased due to an augmentation of both SWS and PS. Finally, there is large individual variation between horses in the time they spend recumbent and sleeping. [15]Horses spend 11% to 20% of the total time in recumbency.[11 and 15] Lateral recumbency represents about 20% of total recumbency time, and uninterrupted periods of lateral recumbency vary from 1 to 13 minutes (mean, 4.6 min). [14 and 16] Steinhart [11] found that the mean length of uninterrupted lateral recumbency periods was 23 minutes, the longest period being one hour. Total sleeping time in the stabled horse averages 3 to 5 hours per day or 15% of the total time. [8, 13 and 16] Keiper and Keenan [24] found similar time budgets in feral horses that were recumbent approximately 26% of the night. PS is about 17% to 25% of total sleeping time, and the mean length of a single PS period is 4 to 4.8 minutes. [13 and 18]In stabled horses sleep is mainly nocturnal and occurs during three to seven periods during the night.[8, 13 and 16] Ruckebusch [13] observed that neither sleep nor recumbency occurred during daytime in three ponies observed for a month and, in another experiment conducted on horses, PS occurred only during nighttime. [15] A group of ponies observed for more than a month between 8:45 and 4:45 spent only 1% of the daytime recumbent.[25] The maximum concentration of sleep occurs from 12:00 to 4:00 .[8, 16, 18 and 24]The purpose of this study was to examine two groups of horses in a familiar environment, one group kept on a bedding consisting of straw, and the other kept on wood shavings, and to determine if there was any difference between the two groups in the time they spend recumbent.

Materials and methods

Housing. The study was conducted in one of the biggest riding clubs in Denmark, housing about 150 horses. The 18 horses used in the study stood in three different parts of the stable. They were all stabled in boxes measuring 3 × 3 m and subjected to the same feeding and management routine. They were unable to see their next-door neighbor because of a tall wooden board, but they were able to see the horses stabled on the opposite side of the corridor through bars. Nine horses were stabled on wheat straw (15 cm long, dry matter content 87-88%) and nine on oven-dried wood shavings (80% spruce and 20% pine, dry matter content 82%).Animals. All horses used in the study were privately owned. They had been kept in the boxes in which they were observed a minimum of three weeks. Three of the horses were mares and 15 were geldings. Most of them were Danish Warmblood used for dressage riding. Their ages ranged from 5 to 18 years (mean, 10.6 y) and their height ranged from 1.60 to 1.76 m (mean, 1.68 m). All horses wore a blanket. Age and sex distribution between the two groups is shown in Table 1.     

Chick Edema Disease Syndrome in Young Turkey Poults

Two feeding bioassays were conducted to study the mortality pattern, incidence of edema and ascites formation and plasma composition of turkey poults fed diets containing varying levels of toxic fat (fat contaminated with polychlorinated dibenzo-p-dioxins) and/or salt. No significant changes in plasma concentrations of electrolyte and total protein and packed cell volume were observed in slaughtered poults fed diets containing toxic fat compared with poults fed a normal diet. However, a positive dose-response relationship between levels of dietary toxic fat (0,2 and 5%) and incidence of mortality with edema, ascites and hydropericardium was observed in poults fed diets containing 1% salt. The toxic effects of polychlorinated dibenzo-p-dioxins were accentuated by increasing the level of salt (0.5, 1 and 3%) in the diet. Mortality started at nine days of age and increased on days 10 and 11. The present experiments demonstrated that gross pathological changes similar to those reported for “chick edema disease” caused by feeding polychlorinated dibenzo-p-dioxins, could also be produced in young turkey poults. The etiology of the toxic effects of these organic compounds in edema formation is discussed.     

Chopped palm leaves as an acceptable bedding material for broiler production

An experiment was conducted to examine the suitability of chopped palm leaves to utilize as a bedding material, compared to wood shavings or wheat straw, on growth performance, immune response, and air quality for broiler production. Three bedding materials were used: wood shavings, chopped palm leaves, and wheat straw. A total of 3,240 one-day-old broiler chicks (Ross 308) was randomly distributed into 3 litter groups (1,080 birds each). Each group had 6 replicate pens (180 birds/pen). All birds were kept under similar environmental conditions, except for bedding material. The obtained results revealed that the growth performance and total mortality rate were not significantly affected by bedding material type. However, using chopped palm leaves as bedding material significantly reduced (P < 0.05) ammonia emission compared to wood shavings and wheat straw (4.1, 7.3 and 8.4 ppm, respectively). A similar trend was observed for settled dust concentration (4.0, 10.3, and 5.9 g/m², respectively). Moreover, an improvement in cell-mediated immunity was observed in boilers kept on chopped palm leaves. Carcass characteristics were not significantly affected by bedding material. It was concluded that chopped palm leaves are a good alternative bedding material to wood shavings and wheat straw in commercial broiler production.     

Investigating duration of nocturnal ingestive and sleep behaviors of horses bedded on straw versus shavings

Horses are stabled overnight for a number of practical reasons; however, there is little research quantifying nocturnal equine behavioral patterns or the extent to which different environments influence nocturnal behavior. The aim of this study was to establish whether differences in duration of sleep and ingestive behaviors were apparent for horses bedded on straw (group 1) or shavings (group 2). Ten geldings of mixed breed (mean age: 7.3 ± 3.53 years) bedded on either shavings (n = 5) or straw (n = 5) were observed between 7 pm and 7 am. Duration of behaviors according to a predefined ethogram was recorded in minutes using a video recorder and continuous focal sampling. Mann–Whitney U tests were used to identify whether any significant differences in duration of ingestion and sleep behaviors occurred for horses bedded on straw compared with shavings. Of the total observation period, group 1 spent, on average, 29.3% of their time budget engaged in recumbent behaviors, compared with 12.2% for group 2. However, no significant differences in duration were established between horses bedded on straw or shavings for standing sleep, sternal recumbency, and lateral recumbency behaviors (P > 0.05). Ingestive behaviors occupied approximately one-third of the time budget, with no significant difference (P > 0.05) observed between groups. On average, group 1 spent a longer proportion of the observation period ingesting bedding (8.1%) compared with group 2 (1%). Duration of bedding ingestion appeared to peak between 1 am and 7 am for both groups. Although not quantified, general observations revealed horses were motivated to alternate between eating hay and bedding in both groups, owing to the prevalence of bedding ingestion. The results indicate that straw bedding facilitates the display of ingestive and sleep behaviors, whereas horses bedded on shavings spent a greater proportion of their nocturnal time budget engaged in “other” behaviors. Further research is required to investigate the extent to which different types of bedding material enrich the environment of horses that are stabled overnight.     

Effect of bedding types and different nutrient densities on growth performance,visceral organ weight,and blood characteristics in broiler chickens

The principal objective of this study was to assess whether bedding types could influence the growth performance of broiler chickens fed on high and low nutrient density diets. The broilers were bedded with clean hulls or shavings. Four hundred eighty male broiler chickens (Ross) were divided into 6 treatment groups, including 1) a high-density diet with rice hulls, 2) a high-density diet with wood shavings, 3) a high-density diet with coconut hulls, 4) a low-density diet with rice hulls, 5) a low-density diet with wood shavings, and 6) a low-density diet with coconut hulls. Weight gain, feed intake, G:F, visceral organ relative weight, red blood cells, white blood cells, and lymphocyte concentrations were evaluated. The bursa of Fabricius, liver, and abdominal fat relative weight, white blood cells, and lymphocyte concentrations were not altered consistently by any of the treatments. For the overall period, weight gain and feed intake were greater in the coconut hull treatment groups as compared with the wood shavings treatments (P < 0.05). Feed intake was also greater in the low-density diet than in the high-density diet treatment groups (P < 0.05). The concentration of red blood cells in blood was reduced significantly by wood shavings bedding compared with the rice hull treatments (P < 0.05).     

Horse hair coat cleanliness is affected by bedding material: A comparison of clean and used wheat straw, wood shavings and pelleted newspaper

Wheat straw, wood shavings and pelleted recycled newspaper were used as bedding materials and compared in maintaining horse hair coat cleanliness. Each material was sampled prior to use and after use having been wetted with urine in a bedding study conducted with 4 adult horses in box stalls. Because feces were removed daily during stall maintenance, frehhly voided feces were also collected so that all components in a used bedding (clean portion, wetted portion, feces) were represented. Hair coat cleanli-ness was measured in vitro by exposing a tanned pony hide with hair to clean and wet beddings as well as feces. Cleanliness was evaluated in terms of the amounts of moisture, volatile-N and solid matter transferred from each component and type of bedding material to the haired hide. Transfers to wool flannel were also measured as a comparison to the haired hide. Woolen products are used in the horse industry and also come into contact with components of used bedding. Freshly voided feces and used beddings transferred more (P<.05) moisture (85 and 54%, respectively) than clean beddings. Wheat straw transferred less (P<.05) solid matter (86 and 64%, respectively) than wood shavings or pelleted newspaper. Wood shavings transferred more (P<.05) solid matter than wheat straw or pelleted newspaper to wool flannel resulting in a statistically significant used bedding X surface interaction. These data indicate that type as well as components of used beddings affect hair coat cleanliness. The ability of a bedding material to maintain hair coat cleanliness should also be a factor (e.g., cost, availability, moisture holding capacity, nontoxicity) in its consideration for use as a bedding for animals.     

Suspected wood poisoning caused by Simarouba amara (marupá/caixeta) shavings in two dogs with erosive stomatitis and dermatitis

Two male Labrador retrievers developed bleeding erosions/ulcerations involving the oral mucosa, mucocutaneous junctions of the lips, nose, prepuce and anus, ulcerated nodules on the chin, and crusting lesions on the elbows, hocks and scrotum. One of the dogs was anorexic and depressed, had haematological abnormalities consistent with damage to the liver and signs of neurological disease. As these dogs had recently been exposed to bedding containing Simarouba amara shavings and because of the striking similarities of clinical signs to those described for horses, a probable diagnosis of wood poisoning was made. This assumption was supported by the clinical course as healing of skin lesions occurred when the dogs were no longer exposed to the bedding.     

Generation of Airborne Particles from Different Bedding Materials Used for Horse Keeping

Among other factors (eg, feed), bedding material has an important effect on stable air quality with respect to airborne particle formation. This study was designed to establish which material is suited to create an improved stable environment for horses. First, the following materials were analyzed under standardized conditions in a laboratory experiment: wheat straw, dry wood shavings, hemp shives, linen shives, wheat straw pellets, paper cuttings (unprinted newspaper). The second investigation was carried out under in situ conditions in which three of these bedding materials (wheat straw, wood shavings, and straw pellets) were analyzed under practical conditions. In both experiments, airborne particle concentrations were detected online with the gravimetrically measuring analyzer TEOM 1400a (Rupprecht & Patashnick Co., Franklin, MA). In the laboratory experiment, the TEOM was equipped successively with different inlets to measure the particle fractions PM₁, PM_2.5, PM₁₀, and PM₂₀. During the in situ experiment, only the fraction PM₁₀ was detected. In the laboratory experiment, hemp and linen had the highest generation of airborne particles in all fractions. The lowest particle generation was detected with straw pellets. Results of the in situ investigation supported results of the laboratory experiment with respect to mean particle generation of straw pellets. With an average of 111.2 ± 149.2 μg/m³, it was significantly lower than the mean particle generation of wheat straw with 227.5 ± 280.8 μg/m³. The particle generation of wood shavings had an average of 140.9 ± 141.9 μg/m³ and also was significantly lower than the generation by wheat straw. An activity-correlated variation of particle concentrations was found. In conclusion, taking both experiments into consideration, straw pellets seemed to be suitable for horse stables, to promote an improvement in the stable climate in relation to airborne particle formation.     

Air hygiene in stables. 1: Effects of stable design, ventilation and management on the concentration of respirable dust

The concentration of fungal spores, the main constituents of respirable dust in stables, is determined by rates of release from fodder and bedding and rate of clearance, principally by ventilation. This paper outlines the principles that govern the application of natural ventilation to the control of air hygiene in barns and individual boxes for horses. When release rates are low, ventilation rates over four air changes per hour are satisfactory. Ventilation was satisfactory in individual boxes but usually unsatisfactory in barns and specific recommendations are made for improvement. Preliminary observations in stables with clean, well-managed bedding revealed only small differences between straw, wood shavings and paper. In these circumstances hay tended to be the major source of respirable spores.     

Higher Chlorinated Dioxins Implicated in the Mortality of Young Pigs Kept on a Pentachlorophenol-treated Wooden Floor

Young pigs raised on a pentachlorophenol-treated wooden floor showed a high mortality. The deaths ceased when the original treated wood was covered with untreated plywood. Analysis of the wood, mother's milk, and young pig tissues was carried out for pentachlorophenol and chlorinated dibenzo-p-dioxins. Pentachlorophenol was found in the wood and mother's milk but not in the young pig tissues. Concentrations of the higher chlorinated dioxins were found in the wood at the ppm level, in the mother's milk at the low ppt level and in the skin and liver of the young pigs at the ppb level. A comparison of the concentrations of hexa-and hepta-dioxin isomers in the wood, and in the piglet skin and liver indicated that a selective absorption and/or metabolism of these isomers had occurred. The results of this case history implicate the higher chlorinated dioxins in the mortality of the young pigs and underline the danger of using technical pentachlorophenol for wood treatment in association with food producing animals.     

Effect of less intensive rearing conditions on litter characteristics, growth performance, carcase injuries and meat quality of broilers

1. The objective was to compare the effect of two litter types (wheat straw and wood shavings) and two different rearing conditions (Treated and Control) on welfare indicators, broiler performance, carcase injuries, particularly hock and foot pad dermatitis (FPD), litter characteristics and meat quality. 2. Treated conditions were characterised by a low stocking density (11 birds/m(2)), short photoperiod (16 h light: 8 h dark) and a large amount of litter (3 to 4.5 kg/m(2), respectively, for wheat straw or wood shavings). Control conditions were a high stocking density (14 birds/m(2)), long photoperiod (23 h light:1 h dark) and small amount of litter (2.3 to 3 kg/m(2), respectively, for wheat straw or wood shavings). In addition, the effects of two widely used litter materials, wheat straw and wood shavings, were investigated. 3. The combined effects of lower stocking density, greater amount of litter material and a photoperiod similar to the natural one, reduced the occurrence of FPD in Treated groups keeping the FPD score under the European threshold. 4. Improved rearing conditions led to faster growth rate associated with inferior feed efficiency, whereas litter type exerted negligible effects on broiler performance. 5. Litter moisture content, nitrogen and ammonia released by the litter were lower in Treated groups than Control groups. The use of wood shavings resulted in lower moisture and nitrogen concentrations in the litter.     

Some preliminary observations on the possible relationship between ammonia production from soiled bedding in calf rearing sheds and calf illness

A limited field study of covered facilities used for raising dairy calves suggested that respiratory disorders and death rates were highest when calves were continuously housed on bedding composed of wood shavings, where ventilation was poor and where automatic feeders were installed. High concentrations of ammonia were found in the urine-soaked bedding following overnight incubation. A prolific growth of mixed micro-organisms isolated from the shavings rapidly colonised plates of selective urea medium. Death rates of 10% and 13.5% were observed on two properties. Respiratory distress was common and lung disease was intractable to treatment on these farms. A histopathological diagnosis of subacute purulent pneumonia with distal necrotising bronchiolitis was made, similar to lung lesions produced experimentally in cats, guinea pigs and rabbits exposed to ammonia gas.     

Chronic obstructive pulmonary disease in the horse. 2: Therapy

The therapy of equine chronic obstructive pulmonary disease (COPD) essentially entails minimising the horse's exposure to the aetiological antigens which are predominantly thermophilic actinomycetes and moulds occurring in hay and straw. This can be achieved, for example, by keeping affected horses permanently out of doors, or when stabled, using shredded paper, wood shavings or peat moss as bedding and feeding a complete cubed diet. There should be no supplementary hay feeding apart from dust-free vacuum-packed hay. Applying such measures generally allows horses to become asymptomatic in seven to 14 days. Bronchodilators and corticosteroids bring about a marked, but temporary, improvement and can be of value in the treatment of acute attacks. The use of oral bronchodilators in combination with environmental control measures may hasten the remission of clinical signs in affected horse. Inhaled sodium cromoglycate can be used prophylactically in asymptomatic horses to prevent the onset of COPD when unavoidable antigen exposure is anticipated.     

Water Absorption Capacity of Flax and Pine Horse Beddings and Gaseous Concentrations in Bedded Stalls

It can be a challenge to find suitable horse bedding materials that provide higher moisture absorption, better animal comfort, greater fertilizer values, and improved indoor environment. Our first objective was to determine the water absorption capacity (WAC) of two bedding materials, flax shive (FS) and pine wood shavings (PWS), commonly used by equine facilities. The second objective was to measure ammonia (NH₃), hydrogen sulfide (H₂S), and greenhouse gas (GHG) concentrations emitted from these bedded stall surfaces. In this study, the WAC of bedding materials were measured at 0.5, 1, 2, 3, 4, 6, 8, 12, and 24 hours in the laboratory. A total of eight horses were used for a 14-day study period. Of these, four horses (group-1) were bedded with FS and the other four (group-2) were bedded with PWS for week-1. In week-2, bedding materials were switched between the two groups. Ammonia and H₂S were measured in situ. For GHG measurement, air samples (methane [CH₄], carbon dioxide [CO₂], and nitrous oxide [N₂O]) were collected 152 mm above the bedded stall surface in Tedlar bags using a vacuum chamber and analyzed for GHG using a gas chromatograph. The WAC of FS was 56% greater than the PWS. There were no significant differences in NH₃, H₂S, CH₄, CO₂, and N₂O concentrations between the two bedding materials (P > .05). Nutrient contents between fresh and soiled bedded samples for each bedding type were different (P < .05). Measured nutrient contents between fresh FS and PWS and bedded FS and PWS bedding materials were similar (P > .05).     

Effect of Feeding Endophyte-Infected Feed and Bedding on the Performance of Broilers

Two varieties of chopped grass seed straw, tall fescue (Festuca arundinaces L.) and perennial ryegrass (Lolium perenne L.), were identified as alternative sources to wood sawdust or shavings as bedding for use by Pacific Northwest broiler producers. However, some broiler growers expressed concern that straw may be contaminated with endophytes, symbiotic fungi that are known to be toxic to livestock. The primary toxic compound of concern for livestock in endophyte infected grass straw is ergovaline.Two experiments were conducted to determine if broiler performance was affected by either the feeding of endophyte infected grass seed containing ergovaline, or rearing broilers on endophyte infected grass seed straw. The exposure of broilers to either endophyte-infected chopped straw as bedding and/or feeding endophyte infected ground grass seed in the diet with ergovaline levels as high as 423 ppb, did not significantly affect performance or the micro anatomy of kidney or liver tissues.     

Evaluation of Factors Influencing the Generation of Ammonia in Different Bedding Materials Used for Horse Keeping

Bedding material is an important factor in determining stable air quality in terms of ammonia formation. The objective of this study was to analyze different bedding materials used for horse stables under standardized conditions, to determine which material is best suited for improving the climate of a stable. The particular concern was a reduction in gaseous ammonia concentrations. Therefore, the following materials were examined: wheat straw, wood shavings, hemp shives, linen shives, wheat straw pellets, and paper cuttings. Twelve containers were constructed in an environmentally controlled room, and the same material was placed into two containers, with the amount of material used being determined by its carbon content. A defined ratio of horse manure/urine mixture was added daily to each container over a period of 14 days. The concentrations of gaseous ammonia, carbon dioxide, nitrous oxide, and water vapor were measured continuously above the bedding within the containers. Means of gaseous ammonia were found to be 178.0 mg/m³ for wheat straw, 155.2 mg/m³ for wood shavings, 144.6 mg/m³ for hemp, 133.7 mg/m³ for linen, 60.3 mg/m³ for straw pellets, and 162.6 mg/m³ for paper cuttings. In conclusion, the results of this study have shown that straw pellets are suitable for horse stables, not only to improve air quality but also, first and foremost, in relation to ammonia binding and ammonia transformation within the bedding material, respectively. However, straw pellets may also have disadvantages. The high substrate temperatures that were measured in straw pellets could favor the growth of pathologic germs that can adversely affect animals' health.     

Airborne dust and aeroallergen concentrations in different sources of feed and bedding for horses

Summary

Standardized methods were used to make quantitative and qualitative assessments of respirable dust and aeroallergens in feed and bedding for horses. Concentrations of airborne dust were measured by using a Rion particle counter, and levels of major aeroallergens implicated in chronic obstructive pulmonary disease were measured by using an Andersen sampler. Laboratory conditions allowed comparison of the different sources of forage, supplements, and bedding without external influences such as ventilation, external temperature and horse activity affecting the result. Crass silages of approximately 50 % dry matter and alfalfa pellets appeared to be very good sources of forage with low levels of dust and aeroallergens. The studied good quality straw was significantly less dusty with fewer allergens than the wood shavings. Supplements, such as whole grains and molassed concentrates, contained many respirable particles and aeroallergens. Rolled grains were significantly more dusty than good hay.