The effect of grain type and processing on equine chewing time

Abstract

SummaryAn experiment was conducted to study the hypothesis that increased grain NDF and feed particle size result in increased chewing time in horse. Three adult Standardbred horses (Group I) and 3 adult Icelandic horses (Group II) were fed 3 daily meals during 3 consecutive days in two 3 x 3 completely randomized block design experiments. Meals of (Group I: 1.0 kg and Group II: 0.5 kg) oats, barley and wheat were fed whole, rolled and ground at 10 am, 12 pm, 2 pm. Chewing activity was measured using a special chewing halter. The basic chewing rate is estimated as jaw movements (JM) per min. Efficient chewing time (EPTIME) in min per kg DM is chewing time corrected for pauses. Regularity of JM is standard deviation of time intervals between individual JM. Faecal particle size was analysed using sieving technique and image analysis. The mean EPTIME was 22 and 15 min/kg DM grain (P<0.01) for Icelandic and Standardbred horses, respectively. The basic chewing rate, chewing regularity and faecal particle size did not differ between horses. The EPTIME for whole grain was 18 min/kg DM but not systematically shorter than for ground grain (20 min/kg DM). EPTIME for oats was 21 min/kg DM but not significantly longer than wheat (18 min/kg DM). Jaw movements were systematically more regular during intake of whole grain as compared to ground grain (P<0.01). In conclusion, the presumed hypothesis could not be accepted. The achieved results indicate that regularity of jaw movements during eating provide a new method for quantifying cereal grain characteristics. The achieved results indicate that regularity of jaw movements during eating provide a new biological method for quantifying cereal grain characteristics.Keywords: chewing, grain characteristics, NDF, Icelandic horse, Standardbred, faecal, particle size Auswirkung von Getreideart und -verarbeitung auf die Kauzeit beim PferdDie Hypothese des Experiments war, dass höhere NDF-Gehalte in Getreide und gröbere Vermahlung beim Pferd in einer längeren Kauzeit resultieren. Drei erwachsene Traberpferde (Gruppe I) und drei erwachsene Islandpferde (Gruppe II) wurden drei Mal täglich, während drei aufeinander folgenden Tagen gefüttert. Des Experiment wurde als 3 x 3 Block-Design organisiert. Die Mahlzeit (Gruppe I: 1.0 kg und Gruppe II: 0.5 kg) bestand aus Hafer, Gerste und Weizen. Es wurde als ganzes, walzenförmig und gemahlen um 10 Uhr, 12 Uhr und 14 Uhr verabreicht. Die Kauaktivität wurde mit einem speziellen Halfter gemessen. Die Standardkaufrequenz ist angegeben als (JM) pro Minute. Die effektive Kauzeit (EPTIME) in Minuten pro kg TS ist die Kauzeit berichtigt um die Pausen. Die Gleichmäßigkeit des JM ist die Standardabweichung von Zeitintervallen zwischen den einzelnen JM. Die Größe der Kotpartikel wurde analysiert unter Anwendung der Siebtechnik und Bildanalyse. Der Mittelwert des EPTIME war zwischen 22 und 15 min/kg TS Korn (P<0.01) für Islandpferde beziehungsweise Traber. Die Standardkaufrequenz, die Gleichmäßigkeit des JM und die Größe der Kotpartikel waren nicht verschied...

Effect of feed type and essential oil product on equine chewing activity

“…The time spent for eating muesli meals (minutes/kg DM) was significantly longer than other concentrate meals in this research, and muesli is generally touted by the horse feed industry to increase eating time. The results obtained are in contrast to the earlier published results by the author (Brøkner et al., 2006). The physical form of the ground oats, whole oats and feed pellet meals used in this research are more homogenous than muesli and without the clumps of feed particles seen in the muesli product.…”

“…The physical form of the ground oats, whole oats and feed pellet meals used in this research are more homogenous than muesli and without the clumps of feed particles seen in the muesli product. The muesli used in the present research contained large pieces of alfalfa chaff (30%) and greenhay (5%) whereas the muesli product used in Brøkner et al (2006) was more homogeneous (3.5% alfalfa chaff). The significantly longer eating duration (per kg DM) is not the result of the selectivity in the muesli product as effective eating time only includes jaw movements and not time spent nuzzling the feed.…”

“…Time spent eating during the 4 days of sampling was visually observed and jaw movement oscillation values (JMOV) (Nørgaard and Hilden, 2004) were recorded by using a special chewing halter (Brøkner et al., 2006). The JMOV were sampled at 25 Hz by a data logger harnessed on the back.…”

“…Equine preference and aversion for various feeds have previously been estimated based on video recordings, personal observations and calculated feed intake (Cairns et al, 2002;Goodwin et al, 2005). Brøkner et al (2006) demonstrated a method to quantify chewing activity in equine fed different grains processed by different methods. Horses are sensitive to organoleptic properties of feed and are capable of selecting against repellent odours and flavours.…”

Equine pre-caecal and total tract digestibility of individual carbohydrate fractions and their effect on caecal pH response

“…Such disappearance can take place independent of digestive processes and may lead to overestimation of the in vivo digestibility. In the present study, feedstuffs were ground to imitate equine chewing activity (Brøkner et al 2006), and attempts were made to avoid that particles were lost from or entered the bags by using 11 mm pore size. Efforts were also made to ensure free exchange of fluid between the bag content and gut content by keeping the weight to surface area (0.22-0.89 mg/mm 2 ) below the recommended 1 mg/mm 2 (Macheboeuf et al 1996).…”