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A 2-yr study was conducted to evaluate 1) the effects of nitrogen level from swine lagoon effluent on forage composition and animal performance and 2) the effects of supplemental escape protein (EP) on performance by steers grazing pastures fertilized with swine lagoon effluent. Bermudagrass (Cynodon dactylon) pastures were fertilized via sprinkler irrigation with either 448 or 896 kg/ha of N from swine lagoon effluent (two pasture replications/treatment). Within each pasture, four supplement treatments were evaluated using electronic Calan gates (8 steers[center dot][pasture.sup.-1][center dot][yr.sup.1]). The treatments were 1) negative control (pasture only); 2) energy control, which supplied 79.9 g of EP[center dot][hd.sup.-1][center dot][d.sup.-1]; 3) 159 g of EP[center dot][hd.sup.-1][center dot][d.sup.-1], and 4) 239 g of EP[center dot][hd.sup.-1][center dot][d.sup.-1]. Gains were increased (P < .05) an average of .15 kg/d by supplementation, with no differences in gain among supplements. Forage samples representative of that grazed by steers (CON-SUM) and representative of all available forage (AVAIL) were obtained at 14-d intervals. Total CP content of CONSUM and AVAIL samples were slightly higher (P < .20 and P < .15, respectively) from pastures fertilized with 896 compared with 448 kg/ha of N (20.8 vs 20.0% for CONSUM and 15.2 vs 14.2% for AVAIL). Concentrations of nonprotein N and soluble true protein (% of CP) in both AVAIL and CONSUM samples were higher (P < .06) from pastures fertilized with the higher N level. Total N uptake by the plant, based on CP content and animal grazing days/ha, was essentially the same for both N treatments. Key Words: Bermudagrass, Beef Cattle, Nitrogen, Pig Slurry, Soil Amendments

Four .8-ha pastures of bermudagrass (Cynodon dactylon [L.] Pers.) were fertilized with either 456 or 873 kg/ha of nitrogen (N) from swine lagoon effluent (two replicates per treatment) and grazed by steers over two summers. Within each pasture, steers received forage only, an energy source (corn), a mixture of corn and soybean meal, or a mixture of corn and blood meal via electronic Calan feeders. All supplements were offered at a level of 1.36 kg/d, and the soybean meal and blood meal supplements provided similar quantities of protein. Weight gains were similar among supplemented steers, but supplemented steers gained faster (P < .05) than controls. Nitrogen fertilization level had no effect on steer gains, steer grazing days per hectare, or in vitro dry matter disappearance, NDF, and ADF of clipped forage samples. Plant protein and nitrate ion concentrations were greater (P < .06) in clipped forage samples receiving the higher N application rate. Nitrate ion concentrations were greater in available forage samples from the pastures with the high N application rate. Mean total N and nitrate N concentrations were similar in water samples obtained from monitoring wells for the two N treatments over the 2 yr and there were no year x N interactions. Chloride concentrations were greater (P < .05) and pH and specific conductance were less in water samples collected from the 873 kg than from the 456 kg/ha N treatment. Long-term studies are needed to examine the possible cumulative effects of applying various levels of swine waste to the same land area. Key Words: Swine Lagoon Effluent, Forage, Beef Cattle, Water Quality

Masticated forage provides information related to the quality and fractionation characteristics of a ruminant's diet. This study reports the use of near infrared reflectance spectroscopy (NIRS) to predict the in vitro dry matter disappearance (IVDMD), in vitro organic matter disappearance (IVOMD), and cell-wall concentrations of particle size fractions and the whole masticate of temperature forages. Esophageal extrusa samples, with saliva retained, were obtained from fistulated steers (Bos taurus) that were intermittently grazing tall fescue (Festuca arundinacea Schreb.), orchardgrass (Dactylis glomerata L.), and ryegrass (Lolium perenne L.). Grazing was initiated at canopy heights of 100, 200, and 300 mm during spring and fall of two consecutive years. Samples were collected at the start of grazing at each canopy height and after defoliation to a 50-mm residue. Masticates, quick-frozen in liquid N2, were subsequently lyophilized and dry sieved into seven particle size fractions and, along with a whole-masticate subsample, were scanned for NIRS analyses. A single broad-based calibration encompassing all experimental factors predicted quality constituents within acceptable limits of precision for this methodology. Standard errors of cross-validation (SECV) were 6 g kg to the -1 for organic matter, 16.0 g kg to the -1 for IVDMD, 16.2 g kg to the -1 for IVOMD, 14.8 g kg to the -1 for neutral-detergent fiber (NDF), and 14.3 g kg to the -1 for ash-corrected NDF. Separate calibrations for each species X sample time combination resulted in little reduction in SECV. Sample numbers used in calibration could be reduced to approximately equal to 7% of total samples with SECV of 16.3 g kg to the -1 for IVDMD. Masticate quality constituents of temperate species were satisfactorily predicted by NIRS when obtained from a wide range of seasonal and plant variation.

Black locust (BL; Robinia pseudoacacia L.), a fast growing nitrogen (N)-fixing tree native to the southeastern United States is usually used as a source of timber for fenceposts because of its dense, rot-resistant wood. Besides having the ability to tolerate adverse conditions, BL grows rapidly and is a source of biological N. Biologically-fixed N in the leaves range from 65 to 146 kg N [ha.sup.-1] [year.sup.-1]. In addition, BL foliage (2,390 to 3,260 kg [ha.sup.-1] leaf DM per growing season) provides a potential source of browse for meat goats (Capra hircus). Leaves of BL are rich in crude protein (CP; 17 to 28%). Nevertheless, BL leaves are high in condensed tannins (proanthocyanidins). In vitro true dry matter disappearance (IVTDMD) of BL leaves (62.2%) was much lower than that of Mimosa (Albizia julibrissin) leaves (83.8%) or Honey locust (Gleditsia triacanthos) leaves (71.5%). In addition, incubating BL leaves in the same jars with standard forage samples reduced IVTDMD values of the latter by two to three units. Replacing concentrate (30% of total DM) by BL foliage (25% of total DM) in gamagrass (Tripsacum dactyloides) hay-based diets containing 17.6% CP did not affect goat intake, but decreased digestibilities of DM 16%, CP 24%, and NDF 22%. In addition, CP excreted as a percent of CP intake increased 63%. Increasing the proportion of BL foliage to 50% of the diet DM had no further negative effects on intake or digestibility estimates. Lambs (Ovis aries) fed coarsely ground dry alfalfa (Medicago sativa) or BL foliage with similar CP (20%) were reported to consume 11% more of the former. In addition, digestibility of OM was less than a third, and digestibilities of NDF and CP in BL leaves were less than half those in alfalfa. Compared to lambs fed alfalfa, plasma urea N, ruminal ammonia and branched chain fatty acids values of lambs fed BL were 60, 82 and 80% lower, respectively. Under browsing conditions, meat goats have a high relative acceptance index for BL foliage. Furthermore, when grazed with cattle, meat goats very effectively control BL encroachment of mountain pastures by totally defoliating BL branches within their reach and often debarking tree trunks. Additional research is warranted to examine meat goat performance under grazing situations where animals have free access to a much greater variety of herbaceous plants to counterbalance the negative effects of condensed tannins found in BL. Key Words: Small ruminant, Robinia pseudoacacia, Tannin

Gastrointestinal (GI) parasites are considered to be one of the most prominent health problems of meat goats. Three trials (1998: 5/8 to 7/2 -- T1, 9/25 to 11/6 -- T2; 1999: 9/24 to 10/27 -- T3) were conducted on predominantly fescue pastures to determine the effectiveness of field applications of liquid N fertilizer (LNF) to suppress goat fecal egg count (FEC). Does and wethers of Boer breeding were used to contaminate fields with trichostrongyle eggs. Goats were then housed in a dry lot and dewormed to lower infestation to close to 0 egg/gram feces. Following contamination, fields were flail-chopped to leave a stubble of about 15 cm (T1), 12 cm (T2) or 5 cm (T3) in height. Fields were then divided into treated (LNF, N/ha: T1 and T2, 56 kg; T3, 73 kg) or control plots (granular urea, N/ha: T1, none; T2, 56 kg; T3, 73 kg). In T1, two groups of 11 wethers (BW: 46 kg) were rotated among 4 treated or 4 control plots (.12 ha/plot). In T2 and T3, fields were divided into 6 plots (.12 ha/plot) in a 2 x 3 randomized complete block design. Dewormed goats (7 goats/plot; BW: T2, 23 kg; T3, 43 kg) were then control grazed on either treated or control plots throughout the length of each trial. Weekly blood (T2 and T3) and fecal samples (all trials) were taken to monitor blood packed cell volume (PCV) and total protein (TP), and FEC. In T2, one goat/plot was slaughtered on d 7 and another on d 14 after the trial started to determine species and quantity of trichostrongyle larvae ingested from the pastures. Results from T1 indicated that LNF suppressed FEC (P < .04), with the presence of a treatment x date interaction (P < .03), whereas no difference in either FEC, PCV or TP was observed during T2 or T3. In addition, the application of LNF did not affect the number of larvae found in the GI tract of slaughtered goats (T2). Drought conditions during T2, despite irrigation of the plots on six occasions, and drenching (16.5 cm rain) of the experimental site by hurricane Floyd the day after LNF was applied (T3), may have contributed greatly to the lack of response seen in those two trials. Nevertheless, results from T1 indicated that fertilization with LNF could have potential as a component of an integrated GI parasite program to reduce goat worm loads. Key Words: Meat goat, Liquid nitrogen fertilizer, Gastrointestinal parasites

Discusses the abstract of the study 'Winter annual grasses for meat goats,' presented at the American Society of Animal Science's Southern Section conference on January 31-February 4, 2003, in Mobile, Alabama.