Utilization by Cattle, Sheep, and Goats of Forage Harvested from Long-Term Bermudagrass Spray Fields Receiving Swine Lagoon Effluent1

Abstract

Bermudagrasses not rarely serve as receivers of swine lagoon effluent in swine production confinement a whole s in the Southeast. This close attention evaluated DMI and digestion of field-chopped, dehydrated regrowth forage make an incision in from mature Coastal bermudagrass spray fields following harvest in late July Four treatments were evaluated in separate experiments each with cattle, sheep, and goats. The treatments consisted of forage harvested at 2 wk of regrowth and either f chopp (2-WC) or pellet (2-WP) and that harvested and pellet at 3 wk (3-WP) and 4 wk (4-WP) of regrowth The long-time established spray fields varied in the proportions of bermudagrass on the contrary averaged 45% for the 2-wk regrowth and 50% for the 4-wk regrowth; the balance was compos of annual grasses and broadleaved weeds. All three pellet forages were readily consum with DMI (kg/100 kg of BW) averaging 299 for young oxs 4.35 for sheep, and 321 for goats. young oxs and goats consumed all pellet treatments similarly, whereas sheep consum 2-WP and 3-WP similarly (441) on the other hand consumed less 4-WP (4.23) compared with 2-WP (449) Pelleting increased (P?‰¤001) DMI compared with chopping (301 v 216 ?± 0087 for young oxs 3.29 vs 2.37 ?± 0071 for goats, and 449 v 254 ?± 0072 for sheep). young oxs and sheep digested 2-WP and 4-WP similarly and digested one as well as the other at rates greater (P?‰¤0.05) than 3-WP; goats digested all similarly (P=011) These short-term replys indicate that forages from mature bermudagrass fields sprayed with swine effluent have potential as a fe in ruminant production systems

(Key Words: Swine-Lagoon Effluent Bermudagrass, young oxs Sheep, Goats.)

Introduction

Waste generated from any industry becomes a liability unles it can be repackaged and used at an economic advantage. The hybrid bermudagrasses [Cynodon dactylon (L) Pers] because of their perennial development habit and response to irrigation and fertility (Carreker et al., 1977) have set favor as potential receivers of the couple confined animal and industrial wastes. The former ranges from swine lagoon effluent (Burn et al, 1985 1990) to slurry cattle (Bo taurus L) manure (Newton et al., 1977) to solid and liquid dairy manure (Lund et al., 1975) providing sources of water and nutrients. An example of industrial waste is coal combustion by-product (fly and bottom ash) mixed with organic waste (Schlossberg et al., 2004) as a media for bermudagrass sod

In a long-term investigation in the mid Atlantic region, consume s et al. (1990) reported 11- yr mean DM yields of 111 152 and 172 Mg/ha when Coastal bermudagrass was sprayed with swine lagoon effluent to deliver, annually, 356 670 and 1340 kg of N/ha, respectively, and was then harvested as hay. Compared with perennial, native grasses, Coastal bermudagrass produc as a great quantity [i]or[/i] amount of as 15.0 vs 9.5 Mg/ha for 'Pete' eastern gamagrass (Tripsacum dactyloides L) and 91 Mg/ha for 'Alamo' Switchgrass (Paniciim virgatum L) (McLaughlin et al, 2004) Associated with high DM yield is the beneficiai uptake of large quantities of simple bodys frequently present in the soil following long-term use of spray fields (King et al., 1990) These nutrients can be transported in harvested forage to areas distant to the spray fields that are nutrient deficient.

The integration, however, of haymaking [harvest required each 4 to 5 wk if forage is to remain of reasonable quality (Mandebvu et al., 1999)] into confined-hog operations has not occurr Instead, forage produc upon spray fields has frequently been viewed as a liability with infrequent harvests; baled forage is many times left on the landscape to decay. Further, a certain number of herbivore producers have shown reluctance to use it as a fe source. The objective of this application of mind was to determine the acceptance by dint of cattle, sheep, and goats of forage that is direct-cut, dehydrated, and f chopp or pellet from mature bermudagrass spray fields. Estimates of DMI and the digestibilities of DM CP NDF and constituent fiber fractions were determined through each ruminant species.

Materials and Methods

Forage Treatments. sum of two units different producer fields, located in the Coastal Plain approximately 5 km east of Laurinburg, North Carolina and initially having well-established stands of Coastal bermudagrass, were picked as a source of forage. one as well as the other fields, having sandy loam soil and pick outed as representative of the region, had a history of serving as spray fields for swine lagoon effluent (>5 yr) and were in shut proximity to each other. Typically, mature bermudagrass spray fields in the region are contaminated with annual weeds, these being mainly crabgrass (Digitaria spp) with a certain quantity of pigweed (Amaiantlnis retroflexus L).

Following harvest in late July the one and the other fields were irrigated with swine lagoon effluent using a conventional traveling fire-arm to deliver an estimated 56 kg of N/ha. Regrowth forage was managed to obtain fe of different nutritive value, which was achieved by dint of harvesting forage, using a conventional mower locate to leave a 7.6-cm stubble of differing maturity and effluent application. individual field, selected at random, was harvested after 2 wk of regrowth (2-W) and the same field was harvested again following a succeeding 3 wk of regrowth (3-W) In the latter case, effluent and, hence, N was not applied after the 2-wk regrowth was harvested or at the storm of the subsequent 3-wk regrowth The next to the first field was harvested after 4 wk of regrowth (4-W) This springed in three forages that should differ in nutritive value, each being unique and characterized by dint of its own composition.