No abstract

The aim of this study was to evaluate the effects of processed dietary supplements derived from two seaweeds, Saccharina latissima (SL) and Ascophyllum nodosum (AN), on microbial methane production and fermentation profile using in vitro methods. Four dual-flow continuous culture fermenters were utilized in a 4x4 Latin Square design to assess these 4 supplements: unwashed, coarsely milled SL (UNW), 3-min rinsed SL (3MR), 20-sec blanched SL (20SB), and a crude phlorotannin extract from AN (PHLT). Treatments were randomly assigned to fermenters and were top dressed on the total mixed ration (TMR) at 5% of total dry matter (DM). Four, 10-d experimental periods were conducted, consisting of a 7-d equilibration period followed by a 3-d sampling period. Vessel pH was continually measured, and effluent samples were collected for volatile fatty acid (VFA) analysis and calculation of DM, organic matter (OM), neutral detergent fiber (NDF) and acid detergent fiber (ADF) digestibilities. Methane was measured prior to the first AM and PM feedings during the 3-d sampling period. Data were analyzed using the PROC MIXED procedure of SAS (9.4) with fermenter as the random effect and period and treatment as fixed effects. Processed treatments (3MR= 7.86, 20SB= 5.75, PHLT= 10.46 mg/dL) yielded less methane (P < 0.02) than unprocessed (UNW= 24.06 mg/dL). Apparent digestibilities of DM, OM, NDF and ADF were not affected by treatment. Total VFA (mM) was greater (P = 0.02) in 3MR than PHLT. The acetate to propionate ratio (A:P) was greater (P < 0.01) in PHLT compared with 20SB, 3MR and UNW (5.62 vs 1.47, 1.27 and 1.54, respectively). Time spent below pH 5.8 during fermentation was not affected by treatment. These results indicate that seaweed processing method can affect methane production in vitro without negatively impacting rumen fermentation and should be further investigated using in vivo models.

Per unit energy, fiber is among the most expensive components of the ruminant diet. Wastes from human enterprises may represent the next step in feedstuff investigation. In an effort to minimize the anthropogenic waste contribution, and as a means to find a more cost-efficient resource to feed ruminant animals, our objective was to determine the nutritive value of disposable coffee cups and warmer sleeves in relation to ruminant nutrition. Discarded cups and warmer sleeves were collected from employees at Tarleton State University in fall of 2017. Cups were obtained from five sources, and warmer sleeves were obtained from two sources. Cups and sleeves were dried at 55°C for 72 h and ground to pass through a 2-mm screen. Ground samples were subjected to a batch-culture in vitro true digestibility (IVTD) assay. Original samples and incubated residues were then assayed for DM, NDF, ADF, and CP. Data were analyzed as a random effects model completely randomized design using the MIXED procedure of SAS. There was no effect (P > 0.05) of source (n = 5) or type (cup or sleeve) for contribution to variance of NDF, ADF, IVTD, and in vitro NDF digestibility (IVNDFD). Mean values for NDF, ADF, IVTD, and IVNDFD across samples were 89.5, 81.4, 24.5, and 18.7%, respectively. Results indicate a low digestibility coefficient for these waste products, thus meaning its use as a feedstuff could be questionable. However, such results provide insight into niches where this product and other anthropogenic wastes may fit in the larger picture of ruminant nutrition