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Despite their role in host nutrition, the anaerobic gut fungal (AGF) component of the herbivorous gut microbiome remains poorly characterized. Here, to examine global patterns and determinants of AGF diversity, we generate and analyze an amplicon dataset from 661 fecal samples from 34 mammalian species, 9 families, and 6 continents. We identify 56 novel genera, greatly expanding AGF diversity beyond current estimates (31 genera and candidate genera). Community structure analysis indicates that host phylogenetic affiliation, not domestication status and biogeography, shapes the community rather than. Fungal-host associations are stronger and more specific in hindgut fermenters than in foregut fermenters. Transcriptomics-enabled phylogenomic and molecular clock analyses of 52 strains from 14 genera indicate that most genera with preferences for hindgut hosts evolved earlier (44-58 Mya) than those with preferences for foregut hosts (22-32 Mya). Our results greatly expand the documented scope of AGF diversity and provide an ecologically and evolutionary-grounded model to explain the observed patterns of AGF diversity in extant animal hosts.

The nature and amounts of total dissolved solids (TDS) in brackish groundwater (BGW) sources vary widely, which may have influence on drinking preferences in small ruminants. A study was conducted to evaluate the water intake preferences of different brackish groundwater (BGW) sources in yearling Alpine [initial body weight (BW) = 36.0 ± 4.92 kg] and Spanish (22.0 ± 1.62 kg initial BW) goats and Katahdin (48.7 ± 1.42 kg initial BW) sheep. After a control phase offering tap water only for 7 d, a pairwise preference test was performed by providing one bucket with fresh tap water (FRW) and another with BGW for 3 d followed by 1 d of FRW only for each BGW testing. Thereafter, a free-choice preference test was conducted for 21 d during which five buckets were simultaneously offered with one FRW and four BGW sources. Four brackish water sources from Oklahoma, were United States Geological Survey (USGS) group 2 (GR-2; calcium sulfate dominant), 3 (GR-3; sodium chloride dominant), and two unclassified groups with sodium chloride and sulfate dominant (GR-U1) and sodium sulfate (GR-U2). The concentration of total dissolved solids in these water types were 494, 7,455, 3,048, 5,459, and 2,650 mg/kg for FRW, GR-2, GR-3, GR-U1, and GR-U2, respectively. In the pairwise test, Alpine and Spanish goats consumed (P < 0.05) GR-U1 lesser amounts (water intake of 23.9 versus 44.6 for Alpine, 43.4 versus 32.5 for Katahdin, and 13.5 versus 44.3 g/ kg BW for Spanish; SE = 8.00); whereas Katahdin sheep consumed (P < 0.05) GR-2 lesser amounts than FRW (24.0 versus 28.1 for Alpine, 6.27 versus 50.4 for Katahdin, and 15.4 versus 32.1 g/kg BW for Spanish; SE = 7.21). There were no significant differences (P >0.05) among the animals for GR-3 and GR-U2 preferences compared with FRW. In the free-choice test, there was a significant (P = 0.001) interaction effect between water source and animal type. Alpine goats preferred GR-3 more (P < 0.05) than FRW, GR-U1, and GR-U2 (9.41, 10.4, 14.4, 24.3, and 6.92 g/kg BW), Katahdin consumed GR-U1 most (P < 0.05) followed by GR-3 than other sources (5.95, 36.0, 1.01, 15.8, and 6.53 g/kg BW), and Spanish consumed GR-U1 more (P < 0.05) than GR-2 (10.0, 20.3, 3.66, 12.7, and 3.91 g/ kg BW for FRW, BRL, GR-2, GR-3, and GR-U, respectively; SE = 3.83). This study suggests that drinking water preferences vary among different USGS groups of BGW and small ruminant breeds, indicating taste differences of these BGW sources among the breeds. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the number of goats in pasture grazing on methane (CH4) emissions estimates using the GreenFeed system (GFS). The study involved growing meat goats, approximately 1.2 yr old and body weight (BW) of 23.9 ± 0.63 kg, over seven 2-wk periods. In periods 1, 2, and 3, 24 goats were used (Treatment 1: G-24), while periods 4 and 5 involved 18 goats (Treatment 2: G-18), and periods 6 and 7 used 12 goats (Treatment 3: G-12). The pasture area was divided into three paddocks for grazing, except during gas measurements in a stationary respiration calorimetry system (SCS) room for 2 d, where goats were fed fresh forage from the same pastureland. The GFS was programmed to dispense pellets and measured gas at specific intervals of the day (i.e., at 0700-0800 h, 1300-1400 h, 1900-2000 h, and 0100-0200 h), provided 120 g/d of concentrate pellets to attract goats for gas measurements. Statistical analysis using mixed model procedures of SAS included SCS data from preceding and succeeding periods as covariates for GFS gas data analysis. Daily dry matter (DM) intake was greater (P < 0.001) in G-12 compared with G-24 and G-18, but when expressed g/kg BW, intakes were similar (P = 0.081) across treatments. Conversely, digested DM and gross energy intakes were greater (P < 0.001) in G-24 than in G-18 and G-12 (494, 509, and 577 g/d and SE = 21.3 and 7.91, 8.10, and 9.20 MJ/d and SE = 0.359 for G-24, G-18, and G-12, respectively). Daily CH4 production was unaffected (P = 0.254) by treatment (26.6, 25.2, and 26.1 g/d; SE = 0.819), despite variations in daily GFS visits by goats (3.26, 2.61, and 2.53 visits/d and SE = 0.106 for G-24, G-18, and G-12, respectively; P < 0.001). However, CH4 emissions in g/kg DM intake or digestible DM intake differed among treatments, with G-18 intermediate between G-24 and G-12 (35.6, 33.4, and 32.0 g/kg DM intake, SE = 1.02, P = 0.024; 54.1, 51.2, and 48.9 g/ kg digestible DM intake, SE = 1.71, and P < 0.001 for G-24, G-18, and G-12, respectively). Carbon dioxide production, expressed in g/d and g/kg DM intake, was greater in G-12 and G-18 compared with G-24. Heat production ranked greatest in G-12, followed by G-18 and G-24. Regardless of treatment, CH4 emissions in g/d, g/kg DM intake or g/kg digestible DM intake were greater in GFS than in SCS (25.5 and 9.56 g/d, 33.8 and 14.4 g/kg DM intake, and 51.2 and 23.8 g/kg digestible DM intake for GFS and SCS, respectively; P < 0.001). In conclusion, differences in CH4 emissions in g/kg DM intake and digestible DM intake among treatments suggests that number of animals in grazing pasture may influence CH4 emission estimates in goats. [ABSTRACT FROM AUTHOR]

Resilience to restricted availability of drinking water was evaluated with 44 Dorper (DOR; initial age = 3.7 ± 0.34 yr), 42 Katahdin (KAT; 3.9 ± 0.36 yr), and 42 St. Croix (STC; 2.7 ± 0.29 yr) sheep from 46 farms in 4 regions of the USA (Midwest, MW; Northwest, NW; Southeast, SE; central Texas, TX). Ad libitum water intake was determined during 2 wk of period 1, with 75% of this amount offered in 2 wk of period 2 and 50% in 5 wk (i.e., 5 to 9) of period 3. Body weight and DMI in week 2 of period 1 and week 9 of period 3 were analyzed with a mixed effects model. There was a breed × period interaction (P = 0.023) in water intake relative to BW (6.17, 6.69, and 7.19 in period 1 and 3.04%, 3.26%, and 3.36% BW in period 3 for DOR, KAT, and STC, respectively; SEM = 0.219). There were 3-way interactions of breed, region, and period in BW and DMI in g/d (P < 0.010). For STC, BW was greater (P < 0.05) in period 3 vs. 1 for all regions (50.1, 47.6, 42.4, and 45.8 kg in period 1 and 51.9, 49.3, 44.5, and 47.7 kg in period 3), whereas there was only a period difference for DOR from the MW and SE (61.4, 66.0, 64.6, and 59.6 kg in period 1 and 60.6, 66.5, 65.7, and 62.4 kg) and for KAT from TX (50.1, 47.6, 42.4, and 45.8 kg in period 1 and 51.9, 49.3, 44.5, and 47.7 kg in period 3 for MW, NW, SE, and TX, respectively; SEM = 2.57). In accordance, DMI by STC was similar (P > 0.05) between periods for all regions (1.25, 1.17, 1.06, and 1.16 kg/d in period 1 and 1.12, 1.08, 1.02, and 1.02 kg/d in period 3), as was also the case for DOR from MW and SE but not from NW or TX (1.54, 1.50, 1.30, and 1.41 kg/d in period 1 and 1.41, 1.13, 1.25, and 1.18 kg/d in period 3) and KAT from TX though not from the other 3 regions (1.47, 1.52, 1.48, and 1.40 kg/d in period 1 and 1.06, 1.15, 1.30, and 1.33 kg/d in period 3 for MW, NW, SE, and TX, respectively; SEM = 0.061). In conclusion, based on BW and DMI with water intake restricted at 50% of ad libitum consumption by individual animals, STC appeared more consistent in display of high resilience to restricted water availability, although DOR from 2 regions and KAT from 1 also were relatively resilient. The results suggest benefit to breed comparisons of inclusion of animals from multiple areas and that environmental conditions of regions may have disparate effects with different breeds of hair sheep. [ABSTRACT FROM AUTHOR]

Fifty-four Alpine doelings (initial BW and age of 31.7 ± 0.38 kg and 306 ± 1.9 d, respectively) were allocated to nine treatments individually fed for ad libitum intake of 25% concentrate and 75% forage diets (DM basis). Alfalfa was the forage in the control diet. Other diets contained Sericea lespedeza as the forage, with 1.25% DM of quebracho extract included in the concentrate fraction for a dietary condensed tannin level of 8.4%. Lespedeza treatments were no additive (L) and inclusion of monensin (I) at 22 mg/kg DM (L-I), soybean oil at 3% (L-S), coconut oil at 3% (L-N), I and 3% soybean oil (L-I-S), I and 3% coconut oil (L-I-N), 1.5% soybean oil and 1.5% coconut oil (L-S-N), and I, 1.5% soybean oil, and 1.5% coconut oil (L-I-S-N). The experiment was 12 wk with two 6-wk periods. Gas exchange was determined in weeks 6 and 12, and other measures occurred in weeks 5 and 11. The control diet offered averaged 2.67% nitrogen, 43.8% neutral detergent fiber, and 8.8% acid detergent lignin, and the L diet offered averaged 2.03% nitrogen, 42.8% neutral detergent fiber, and 13.2% acid detergent lignin. There were no treatment × period interactions for digestibilities (P ≥ 0.770) or methane emission (P ≥ 0.324). There were differences (P < 0.001) between the control treatment and diets with lespedeza in intake of DM (1.46, 1.23, 1.30, 1.18, 1.32, 1.10, 1.02, 1.20, and 1.01 kg/d; SEM = 0.059), digestibility of OM (57.4%, 50.9%, 51.8%, 52.7%, 50.3%, 52.1%, 52.1%, 51.9%, and 49.8%; SEM = 1.42), and digestibility of nitrogen (59.1%, 31.2%, 32.5%, 37.1%, 31.6%, 38.3%, 30.4%, 38.4%, and 34.1% for control, L, L-I, L-S, L-N, L-I-S, L-I-N, L-S-N, and L-I-S-N, respectively; SEM = 2.21). Ruminal methane emission was less (P < 0.001) for diets with lespedeza than for the control in MJ/d (1.36, 0.76, 0.84, 0.71, 0.71, 0.66, 0.65, 0.68, and 0.68; SEM = 0.048) and relative to intake of gross energy (5.92%, 3.27%, 3.49%, 3.19%, 2.84%, 2.91%, 3.20%, 3.20%, and 3.27%; SEM = 0.165) and digestible energy (11.19%, 6.98%, 7.40%, 6.38%, 5.90%, 5.69%, 6.37%, 6.38%, and 6.70% for control, L, L-I, L-S, L-N, L-I-S, L-I-N, L-S-N, and L-I-S-N, respectively; SEM = 0.400). In conclusion, the magnitude of effect of condensed tannins from lespedeza and quebracho extract on ruminal methane emission by Alpine doelings did not diminish over time and was not markedly influenced by dietary inclusion of monensin, soybean oil, or coconut oil. [ABSTRACT FROM AUTHOR]