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Poor nutritional quality and increased content of secondary compounds can reduce consumption of Mediterranean shrubs by herbivores. In 2 sequential trials, we examined the effect of polyethylene glycol (PEG) and number of shrub species offered on daily intake of Mediterranean shrubs by 12 sheep and 12 goats. The PEG (25 g) was fed to experimental animals with barley. In trial 1 (6 shrubs), goats ate more (P = 0.0008) daily total shrub biomass than did sheep (60.7 vs. 45.9 [+ or -] 2.6 g/kg of BW). There was a trend (P = 0.08) toward a positive PEG effect on total shrub intake, with PEG-supplemented animals consuming more total shrubs than controls (56.7 vs. 50.0 [+ or -] 2.6 g/kg of BW). Trial 2 (using 3 shrubs) was a continuation of trial 1, except that animals were given less barley and treatment animals were given more PEG (50 g). Both sheep and goats showed a numerical decrease in total shrub intake from trial i to trial 2. Sheep receiving PEG ate more (P = 0.002) total shrubs than did controls, but no PEG effect was found for goats. Thus, PEG had a greater influence on sheep than goats when only 3 shrubs were offered, a result that may be related to the fact that fewer shrubs with complementary secondary compounds were offered and that goats appear to have a greater ability to consume and detoxify secondary compounds from Mediterranean shrubs. Overall, as the number and diversity of shrubs offered increased, supplemental PEG had less effect on increasing intake for both goats and sheep. Key words: chaparral, diet selection, maquis, secondary compound, shrubland, tannin

Appetite stimulants were extracted and partially isolated from high-grain concentrate. The stimulants were fed daily and were palatable to sheep and goats used in the experiments. The stimulative effects were tested by comparing the intake of two types of hay: with or without the extracts. Diethyl ether and n-pentane extracts of the concentrate stimulated feeding in sheep (P < .01 and P < .05, respectively). However, methanol extracts had no significant stimulative effect on selective feeding in sheep. Goats also preferentially fed on hay sprayed with the diethyl ether extracts (P < .01). The diethyl ether extracts were divided into acid, neutral, and basic fractions. Sheep and goats had a marked preference for the acid fraction only (P < .01 and P < .05, respectively). These results suggest that specific chemicals to increase palatability of hay are present in high-grain concentrate and that the chemicals are nonpolar, acidic substances. Key Words: Extraction, Fractionation, Appetite Stimulants, Sheep, Goats, Grain

We described the effects of two East African browses, Acacia brevispica and Sesbania sesban, on nitrogen metabolism of sheep and goats. The A. brevispica had a substantial amount of proanthocyanidins (condensed tannins); S. sesban did not. The browses were fed at three levels in combination with vetch (Vicia dasycarpa) and teff straw (Eragrostis abyssinica). Fecal N, N balance, and plasma urea N (PUN) were estimated with intact animals. Ruminal ammonia (RuA) and VFA concentrations were estimated with ruminally fistulated animals. Urinary N loss, PUN, RuA, and VFA concentrations were higher for S. sesban diets than for A. brevispica diets. Fecal N was highest with diets including A. brevispica due to high levels of fecal neutral-detergent insoluble N. Nitrogen retention was highest for diets including S. sesban. Nitrogen retention was adequate for A. brevispica diets because low urinary N compensated for high fecal N. Four hypotheses describe possible effects of tannins on N metabolism: 1) escape of protein from the rumen to the lower tract; 2) increased microbial yield; 3) increase in N-containing endogenous products; and 4) protein made indigestible in tannin-protein complexes. The effect of tannins in A. brevispica on N metabolism can best be described by the formation of indigestible tannin-protein complexes, although increased production of endogenous products is also possible. Key Words: Sheep, Goats, Acacia brevispica, Sesbania sesban, Nitrogen Metabolism, Proanthocyanidins

Grazing ruminants use both visual cues and taste in selecting their diet. Preference during grazing may not be the same when forage is dried for hay and cut into lengths prior to feeding in confinement. Eight cultivars of tall fescue (Festuca arundinacea Schreb.), previously evaluated for preference while grazed, were harvested three times over a period of 2 yr. The hays were air-dried, baled, and passed through a hydraulic bale processor prior to feeding. Five experiments were conducted. All three harvests were evaluated with sheep and the last two also with goats, using six animals each time. During an adaptation phase, hays were offered alone as meals. In the experimental phase, every possible pair of hays (28 pairs) was presented for a meal. Data were analyzed by multidimen sional scaling and by traditional analyses. Preference was significant among cultivars in all experiments. Multidimensional scaling showed that selection was based on two criteria with two dimensions being significant. Sheep preferred KENHY followed by KENTUCKY 31 and STARGRAZER but preferenced against BARCEL. HIMAG, MO-96, and C1 were intermediate and MOZARK was variable. Goats were similar to sheep in preferring KENHY followed by STARGRAZER and selected against MOZARK and BARCEL. KENTUCKY 31, HIMAG, MO-96, and C1 were intermediate. In all five experiments, the general association was positive for available carbohydrate fractions and negative for fiber fractions that contribute to cell wall rigidity. Key Words: Dry Matter, Festuca, Food Preferences, Goats, Sheep

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