A procedure was developed for extraction of 'free' condensed tannins (CT) using a mixture of acetone/water/diethyI ether (4.7 : 2.0 : 3.3), followed by extraction of protein-bound and fibre-bound CT using boiling sodium dodecyl sulphate containing 2-mercaptoethanol (SDS). CT concentrations in all three fractions were determined by a modified butanolLHC1 procedure. Separate standard curves using purified CT in water or SDS solution were utilised for analysis of extractable C T (water standards) and protein-bound and fibre-bound CT (SDS standards). The method accurately predicted the concentration of CT added to forage extracts. CT extractable in acetone/water/diethyI ether comprised, on average, 68 YO of total CT in a range of freeze dried forage legume samples, with most of the remainder being bound to protein. When total CT concentration was low (0.6-3.0 YO DM). a lower proportion was extractable (33-35 O h ) . In protein concentrate meals containing CT, the extractable. proteinbound and fibre-bound components comprised 15, 60 and 25% respectively of total CT. Total CT concentration in the forages Lorus cornicukutus and Coronillu ouriu was considered appropriate for ruminant nutrition (2.1 and 3.0 YO DM), whilst CT concentration in the forage of Dorycnium spp (13-19 % DM) was more suitable for soil conservation purposes. The substantial CT concentration in cottonseed meal (1.6% DM) may be involved in the high resistance of proteins in this product to ruminal degradation. CT concentration was indistinguishable from zero in perennial ryegrass forage, in barley and triticale grains and in soya bean meal (0.1 YO DM).

The management of food animals prior to slaughter influences both profitability and animal well-being. This experiment was conducted as a split-unit design to determine live weight shrink and stress responses in goats due to differences in stocking density during transportation and holding. A total of 150 Spanish does were transported on two different days (replicate) and held overnight (18 h) without feed in low- (LD) or high-density (HD) groups. On each day, 75 does were transported 2.5 h with floor spaces of .18 m2 and .37 m2/animal in LD (25 does) and HD (50 does) groups, respectively. The average temperatures in the trailer during transportation were 34.6 and 35 degrees C, respectively, on d 1 and 2. All animals were blood-sampled before loading (PRELOAD) and four does from each treatment were sampled immediately after loading (POSTLOAD). Animals were blood-sampled in holding pens either at 0, 1, 2, 3, 4, or 18 h after transportation (time) to assess the time course (n = 8 does per time per replicate) of stress responses. Individual animals were weighed just before loading onto a trailer and after overnight holding to assess shrinkage. Treatment or treatment x time did not have a significant effect on any of the dependent variables studied. There were significant effects of time (P < .01) on plasma cortisol, glucose, and urea nitrogen (PUN) concentrations. Time also had significant effects (P < .01) on plasma creatine kinase (CK) activity, differential leukocyte counts (neutrophils, lymphocytes, monocytes, and eosinophils), and ratio of neutrophils to lymphocytes (N:L). However, plasma leptin concentrations were not influenced by time. Cortisol concentrations increased at POSTLOAD sampling, peaked at 0 h, and decreased thereafter before spiking again at 18 h of holding. The PUN was higher at 18 h than at other time periods studied. Plasma glucose concentrations increased and remained at higher levels at 0, 1, and 2 h and began decreasing at 3 h, reaching PRELOAD levels at 18 h. Plasma CK kinase activity peaked at approximately 2 h after transportation. The N:L ratio was higher at all time periods after transportation than prior to starting the journey, indicating a prolonged effect of transportation stress on the immune system. The mean (+/- SE) shrinkage losses were 10.2 +/- .68 and 9.8 +/- .68 in HD and LD treatment groups, respectively. The results indicate that the stress responses of goats due to transportation begin decreasing within 3 h after transportation. However, prolonged holding periods without feed may increase stress responses and bring about metabolic changes.

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Parasitic infections with gastrointestinal nematodes (GINs) still represent a worldwide major pathological threat associated with the outdoor production of various livestock species. Because of the widespread resistance to synthetic chemical anthelmintics, there is a strong impetus to explore novel approaches for a more integrated management of these infections. The use of nutraceuticals in the control of GINs is one of the alternatives which has been widely studied for 20 years. The objectives of this review are: (i) to define and illustrate the concept of 'nutraceutical' in the context of veterinary parasitology based on data obtained on the most studied models to control GINs in small ruminants, the tannin-containing legumes (Fabaceae); (ii) to illustrate how the 'nutraceutical concept' could be expanded to other plants, other livestock production systems and other GI parasitic diseases, and (iii) to explain how this concept is opening up new research fields for better understanding the interactions between the host, the digestive parasites and the environment.

The purpose of this study was to determine the effects of short-term, preslaughter stress on physiological responses and meat quality in goats of different age groups. The goats (n = 28) were classified into young (6 to 12 mo of age) and old (24 to 30 mo of age) groups, feed deprived overnight, and slaughtered at three different times (replicates). On each slaughter day, goats were either subjected to a 2-h transportation stressor (TS) or remained unstressed in holding pens (NS) before slaughter. Blood samples were collected via jugular venipuncture from TS and NS goats at 2, 1, and 0 h before slaughter. Muscle glycogen and pH were measured on samples from longissimus muscle (LM) collected at 15 min and 24 h postmortem, and instrumental measures of meat color were obtained on the LM after a 24-h chilling period at 4 degrees C. The TS goats had higher plasma cortisol (P < 0.01) and glucose (P < 0.05) concentrations than NS goats. The rates of increase in plasma cortisol, glucose, and nonesterified fatty acid concentrations were greater in TS than in NS goats (stressor treatment x blood sampling time, P < 0.01). Muscle glycogen concentrations were greater (P < 0.05) in NS than in TS goats and higher (P < 0.01) in old vs. young goats; however, pH measured at 15 min and 24 h postmortem was not (P > 0.05) influenced by stressor treatment. Water-holding capacity of meat was not (P > 0.05) influenced by stressor treatment. Older goats had lower (P < 0.01) L* values and greater (P < 0.01) a* and chroma values than the younger goats. The a* and chroma values of loin cuts from young goat carcasses were lower in the TS than NS treatment groups, but this effect was absent in the old goat carcasses (stressor treatment x age, P < 0.05). Cooking loss percentages and shear force values for loin chops aged for 7 d were not (P < 0.05) affected by stressor treatment; however, old goats produced tougher (P < 0.01) loin chops than young goats. These results indicate that short-term preslaughter transport can cause noticeable changes in stress responses and muscle metabolism in goats.

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Three experiments were conducted to determine the fate of condensed tannins (CT) during digestion in sheep. CT were measured as extractable, protein-bound and fibre-bound fractions using the butanol-HC1 procedure. In Expt 1, purified CT were added to digesta from different parts of the digestive tract obtained from a pasture-fed sheep. Recoveries of CT after 0 and 4 h of anaerobic incubation at 39" averaged: rumen 78-9 and 575 % ; abomasum 50.9 and 490 YO ; duodenum 64.4 and 46.0 YO and ileum 43.4 and 38.8 %. In Expt 2, ['4C]CT was given per ubomusum over a 6 5 h period at 15 min intervals to a sheep previously fed on Lotus peduncuZutus (which contains CT). The sheep was killed at the end of the period and 92.4 % of the label was recovered. Virtually all of the label was in the digesta, and none was detected in the blood, so that the CT-carbon appeared not to be absorbed from the small intestine. In Expt 3, rumen, abomasal and ileal digesta and faeces samples from sheep fed on Lotus pedunculutus were analysed for CT and CT flow along the digestive tract calculated from reference to indigestible markers. Values were low in all digesta samples, indicating disappearance of CT across the rumen and small intestine, and CT recovery in faeces was only about 15% of intake. However, the I4C results from Expt 2 suggested that little if any CT-carbon was absorbed and the low recoveries in Expt 1 are considered to be a consequence of either conformational changes to the CT molecule such that it is no longer detectable by colorimetric methods, an inability of the analytical method to release bound CT for the butanol-HC1 assay, or interference from other digesta constituents. It is concluded that the butanol-HC1 method of CT analysis is appropriate for quantifying CT in herbages but not in digesta or faeces, and that a substantial part of CT released during protein digestion in the small intestine may not be detectable by normal CT analytical methods.['4C]Condensed tannin: Digesta tannins : Tannin digestion Condensed tannins (CT) are polyphenolic compounds occurring in a wide range of plants eaten by ruminants (Jones et al. Sarkar et al. 1976; Terrill et al. 1992b). They may be either beneficial or detrimental to the animals' nutrition depending on concentration in the forage, astringency and pH-dependent protein-binding characteristics. The concentration of CT may be as high as 200g/kg plant dry matter (DM) but most of the herbages ingested by ruminants contain 2&100gCT/kg DM (Terrill et al. 1992b). Evaluation of the role played by CT in ruminant nutrition has been hindered by analytical difficulties, especially the quantification of CT in digesta and faecal material. There are two commonly used procedures for CT quantification; the vanillin-HC1 method (Broadhurst & Jones, 1978) and the n-butanol-HC1 method (Bate-Smith 1973; Porter et al. 1986). Both methods are semi-quantitative (Mangan, 1988) so that considerable variation can exist

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