Annual ryegrass (Lolium rigidum) seed survival and digestibility in cattle and sheep

Abstract

A trial was conducted to investigate the survival and digestibility of annual ryegrass (ARG) seed (Lolium rigidum L.) eaten by sheep and cattle. Sheep (n= 8) and cattle (n = 8) were fed a basal diet containing 1:1 lucerne chaff:oaten chaff with (ARG) or without (control) the inclusion of 20% total dry matter of annual ryegrass seed in a changeover design. Intake was restricted to 17 g/kg liveweight. Digestibility of the control diet was lower (P<0.01) for sheep than cattle. Annual ryegrass seed was present (P<0.01) in the faeces of both sheep and cattle within 24 h of first ingestion. Some 10.8 and 32.8% of seed ingested was excreted by sheep and cattle respectively, with 3.9% (sheep) and 11.9% (cattle) remaining germinable. Annual ryegrass seed continued to be excreted by both sheep and cattle up to 5 days after removal from the diet. Dry matter digestibility of the annual ryegrass diet was 53% in cattle.

Opportunities and challenges for harvest weed seed control in global cropping systems

“…Although some seed present in the chaff heaps will remain viable after being consumed by livestock, several studies have shown that only a proportion of grass seeds (< 10%) remain viable after passing through the gut of sheep and cattle . Even when their diet consists of an unusually large proportion of ryegrass seed (20%, ∼79 000 seeds d −1 ), less than 4% of it germinated after being consumed by sheep …”

“…71 Although some seed present in the chaff heaps will remain viable after being consumed by livestock, several studies have shown that only a proportion of grass seeds (< 10%) remain viable after passing through the gut of sheep and cattle. [72][73][74][75] Even when their diet consists of an unusually large proportion of ryegrass seed (20%, ∼79 000 seeds d −1 ), less than 4% of it germinated after being consumed by sheep. 74 HWSC systems where the weed seeds and any harvest grain losses are either removed from the field (bale direct) or destroyed (iHSD) severely limit the nutritional potential of the stubbles when grazed by livestock.…”

“…[72][73][74][75] Even when their diet consists of an unusually large proportion of ryegrass seed (20%, ∼79 000 seeds d −1 ), less than 4% of it germinated after being consumed by sheep. 74 HWSC systems where the weed seeds and any harvest grain losses are either removed from the field (bale direct) or destroyed (iHSD) severely limit the nutritional potential of the stubbles when grazed by livestock. However, if the farmer uses a summer feed lot to maintain ground cover or defer grazing on newly germinated pastures then the bale direct system would provide a ready source of both roughage and some nutrition to their animals.…”

Ecosystem functioning in relation to species identity, density, and biomass in two tunneller dung beetles

“…The percentage of seeds found in dung that are still viable is species-dependent (Milotic & Hoffmann, 2016a,b,c). There are no data on Lolium multiflorum survival through the cow digestive duct, but it is known that only 12% of Lolium rigidum seeds ingested remained viable once it ended up in cattle dung (Stanton et al, 2002). Considering the low rate of L. rigidum seed survival along the digestive tract of cows, we preferred not to place seeds in dung pats (i.e.…”

Survival of weed seeds subjected to sheep rumen digestion

“…Seed dissemination and germination of many crops, grasses and weeds have been reported in the faeces of domesticated and wild animals (Heady, 1954; Lacy et al. , 1992; Stanton et al ., 2002, 2003; Schoenbaum et al. , 2009).…”