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Effects of using ground redberry juniper and dried distillers grains with solubles (DDGS) in Rambouillet lamb (n = 45) feedlot diets on growth, blood serum, fecal, and wool characteristics were evaluated. In a randomized design study with 2 feeding periods (Period 1 = 64% concentrate diet, 35 d; Period 2 = 85% concentrate diet, 56 d), lambs were individually fed 5 isonitrogenous diets: a control diet (CNTL) that contained oat hay but not DDGS or juniper or DDGS-based diets in which 0 (0JUN), 33 (33JUN), 66 (66JUN), or 100% (100JUN) of the oat hay was replaced by juniper. During Period 1, lambs fed CNTL had greater (P 0.41). Compared to 0JUN, lambs fed CNTL had similar (P = 0.12) G:F and tended to have less G:F (P = 0.07) than lambs fed DDGS-based diets. Among lambs fed DDGS-based diets, DMI was similar (P > 0.19), ADG increased linearly (P = 0.03), and G:F tended to decrease quadratically (P = 0.06) as juniper increased in the diet. Serum IGF-1, serum urea N (SUN), and fecal N were greater (P 0.13) for lambs fed CNTL vs. lambs fed DDGS-based diets (CNTL). Within lambs fed DDGS-based diets, SUN increased quadratically (P = 0.01) and fecal N increased linearly (P = 0.004), which can partially be attributed to increased dietary urea and condensed tannin intake. Most wool characteristics were not affected, but wool growth per kilogram of BW decreased quadratically (P = 0.04) as percentage of juniper increased in the DDGS-based diets. When evaluating the entire 91-d feeding trial, results indicated that replacing all of the ground oat hay with ground juniper leaves and stems in lamb growing and finishing diets is not detrimental to animal performance and that DDGS-based diets can reduce total feedlot costs, as compared to sorghum grain and cottonseed meal-based diets. However, compared to using juniper or oat hay as the sole roughage source, using both during the growing period (Period 1) enhanced growth performance and further reduced total feedlot costs.

We conducted this study to describe the intermediate-term periodicities in percentage juniper (Juniperus spp.) in goat diets and to develop optimal sampling schemes to estimate individual animal variation in juniper consumption. Fecal samples were collected from 12 multiparous female Angora goats on Monday and Thursday for a 24-mo period. Percentage juniper in the diet was determined using fecal near-infrared reflectance spectroscopy. Spectral analysis was used to determine the presence and length of cyclic variation in juniper consumption during growing and dormant season periods. Significant periodicities were found for 37% and 68% of the goats in the dormant and growing seasons, respectively. Cycle lengths varied from 9 d in the dormant season to 7 or 8 d in the growing season. The simple coefficient of determination between a two-sample moving average and the mean of all observations on individual goats was highest during a 3-mo period in the spring, which indicates that samples collected in the spring provided the best estimate of the yearlong percentage juniper in the diet. Monte Carlo simulations for 7-d cycles showed the root mean squared difference between estimated and population mean for two samples with 2 or 3 d between samples was only 1% greater than the root mean square difference for three or four samples collected every other day. The optimal sampling strategy for determining the dietary percentage of a species is to collect two samples separated by one-half of the cycle length.

A study was conducted to evaluate the ability of two instruments for measuring luster in Suri alpaca fiber and to compare the results with subjectively assessed luster scores. In addition, the study was designed to determine the correlations between luster and other value-determining, objectively measured physical properties of Suri alpaca fiber. For this purpose, 205 Suri alpaca fleece samples were submitted by 49 breeders that represented a broad cross-section of Suri alpaca in terms of visually assessed luster, color, and fiber characteristics. Raw staples and “washed-and-aligned” staples were independently and subjectively assessed for luster by 2 alpaca judges certified by the Alpaca Owners and Breeders Association (AOBA). The fiber samples were measured for luster and luminance using a SAMBA Hair System and were scanned using a near-infrared reflectance spectrometer. Standard objective test methods were used to measure mean fiber diameter and variability (at mid-staple and overall), prickle factor, comfort factor, mean fiber curvature and variability, medullation (white, beige, and light fawn samples only), laboratory scoured yield, mean staple length and variability, and mean staple strength and variability. The precision of the luster measurement (MLUS) was estimated using CV based on 3 measurements per subsample and averaged 3.9% across all colors. In contrast, precision of the luminance measurement (MLUM) was higher with an average CV of 2.3%. Agreement between the subjective luster scores of 2 certified alpaca judges was low ( r 2 = 0.17 and 0.10 for raw and washed-and-aligned samples, respectively). Despite this, evidence was obtained linking instrument-measured luster and luminance with subjectively assessed luster scores. Two systems were proposed for expressing instrument-measured luster that will permit comparisons between alpacas of different color. Small negative correlations were present between mean fiber diameter and subjectively assessed luster scores. Small positive correlations were present between mean fiber diameter and objectively measured luster values. A strong correlation ( r = −0.94) existed between instrument-measured luster and log 10 luminance. Prediction equations derived from near-infrared reflectance spectra (NIRS) produced precise and accurate estimates of log 10 luminance. The NIRS estimates of instrument-measured luster were less precise and less accurate, and estimates of subjectively assessed luster were neither accurate nor precise. The SAMBA Hair System is capable of producing estimates of luster that are accurate enough to be useful to Suri alpaca breeders who intend to select for this trait.

Effects of percentage of roughage on growth, serum urea N, NEFA, and IGF-1 concentrations and wool, carcass, and fatty acid (FA) characteristics were investigated in Rambouillet wether lambs (n = 33). Lambs were individually fed ad libitum pelleted diets for 98 d containing 40% dried distillers grains and other ingredients, with 10% (CSH10), 20% (CSH20), or 30% (CSH30) cottonseed hulls replacing an increasing amount of ground sorghum grain. Results indicated no interaction between diet and day for lamb BW, ADG, or G:F. Percentage of roughage did not affect lamb BW, even though ADG linearly increased (P = 0.005) as cottonseed hulls increased in the diet. Increasing percentage of cottonseed hulls in the diet linearly increased (P 0.45) for serum urea N, NEFA, or IGF-1 concentrations. Serum urea N linearly increased (P = 0.005) as percentage of cottonseed hulls increased in the diet. All lambs had similar NEFA concentrations, but serum IGF-1 linearly decreased (P = 0.001) as percentage of cottonseed hulls increased in the diet. Lambs had similar wool fiber characteristics except that average fiber curvature and SD of fiber curvature linearly increased (P = 0.03) as percentage of cottonseed hulls increased in the diet. Carcass characteristics and sensory panel traits were not affected (P > 0.19) by diet, except for body wall thickness (quadratic, P = 0.03) and a linear decrease in sustained tenderness (P = 0.02) as the percentage of cottonseed hulls increased in the diet. As cottonseed hulls increased in the diet, percentages of myristic and palmitoleic (linear, P < 0.05) and arachidic SFA (quadratic, P = 0.03) decreased and cis-9,trans-11 CLA increased (linear, P = 0.007). When sorghum grain and cottonseed hull prices are similar to those reported for this study, lamb feeders are advised to use the CSH30 diet vs. CSH10 or CSH20 diets because even though DMI was greater for lambs consuming CSH30 diet, those lambs had greater ADG and the least cost of feed x kg(-1) of BW gain.

A pharmacokinetic dosing study with camphor was used to determine whether selection lines of high-juniper-consuming goats (HJC, n = 12) and low-juniper-consuming goats (LJC, n = 12) differed in their respective disposition kinetics. Postdosing plasma camphor concentrations were used to examine whether a timed single blood sample collected after intraruminal administration of camphor would be a useful screening test to aid in the identification of HJC. Yearling fe- male Boer × Spanish goats (n = 24) received a single intraruminal dose of monoterpene cocktail (0.270 g/ kg of BW) containing 4 different monoterpenes that represented their composition previously reported for Ashe juniper (Juniperus ashei). Camphor, the predomi- nant monoterpene in Ashe juniper, was 49.6% of the mix and was the monoterpene analyzed for this study. Blood samples were taken at 15 time points from 0 to 8 h after dosing. Concentrations of camphor were mea- sured in plasma using solid phase extraction and gas chromatography/flame-ionization detection analysis. Maximal plasma concentration of camphor was greater for LJC than HJC (P = 0.01), and area under the curve extrapolated to infinity was greater for LJC than HJC (P < 0.01). Total systemic exposure (area under the curve) to camphor was 5 times less in HJC goats. We conclude that 1) HJC goats possess internal mecha- nisms to reduce the bioavailability of camphor, and 2) a blood sample taken at 45 min or at 60 min after intraruminal administration of camphor may be use- ful for identifying HJC individual animals from within large populations of goats.

Data from goats (n = 505), collected over a 4-yr period, were used to estimate the heritability of juniper consumption. Juniper consumption was determined by near-infrared spectroscopy on fecal samples (n = 1,080) collected from female Boer-cross goats grazing pastures with a variety of plants, including juniper. The animals with records were progeny of 72 sires. Individual goats had from 1 to 4 observations over a 4-yr period. Predicted juniper consumption for individual observations ranged from -5 to +62% of the diet. Data were analyzed with a mixed model that included management group as a fixed effect, BW as a covariate, and permanent environment, animal, and residual as random effects. Management group was a significant source of variation. Least squares means of juniper consumption, as a percentage of the total intake, for management groups varied from 19 to 47%. Heritability of juniper consumption was 13%. Repeatability of juniper consumption was 31%. These results suggest that progress to selection for goats that will consume greater amounts of juniper is obtainable, but is expected to be slow.

One hundred years ago, there were more than 48 million sheep in the United States. In 1910, they were valued at $4/head, with 43% of income coming from the sale of sheep, lambs, and meat and 57% coming from wool. Over the years, fluctuations in this ratio have challenged the breeder and researcher alike. By 2007, sheep numbers had declined to 6.2 million, with the average sheep shearing 3.4 kg of wool (representing

Castrated Angora kids ( n = 210, initial BW = 25.4 ± 4.0 kg) approximately 7 months of age were used in two consecutive years (2002 and 2003) to evaluate three production systems and coats in terms of animal performance, carcass traits, mohair production and quality, and production costs. In both years, half the animals were assigned to an innovative feeding system (RF) that consisted of an open-sided barn having a raised, slatted floor, and the remaining goats were assigned in equal numbers to traditional feedlot (FL) and pasture (P) systems. Half the goats in each system were fitted with coats. Treatments and coat groups were blocked by body weight. The FL and RF goats had ad libitum access to rations formulated to produce high and moderate growth rates, respectively. Goats in the P treatment were supplemented three times a week to produce moderate growth. After shearing, fleeces were weighed and fully characterized using objective measurements. In 2002 (only), the goats were slaughtered and carcass traits were measured. The rations and supplements were formulated to produce weight gains and fleece weights that should have ranked FL > RF ≥ P. In fact, the FL and RF goats gained faster and grew more than the P goats. Overall gain rates were 124, 61, and 135 g/day for FL, P, and RF, respectively, while corresponding shorn body weights were 37, 30, and 38 kg. The larger animals in the FL and RF systems produced more mohair than goats in the P system (3.3 kg versus 2.8 kg, greasy). Mohair from RF goats was coarser than that from P goats (31.5 μm versus 29.6 μm) and contained lower curvature (18.8°/mm versus 20.6°/mm). System did not affect any of the other measured traits including scoured yield, mohair production efficiency (mohair production/kg BW), medullation, staple length, or any of the measures of trait variability (CV). System had no effect on dressing percentage but the consistent trend for carcass weight, back fat thickness, and body wall thickness, was consistent with live weights, FL = RF > P. As planned, coated produced higher yielding (74% versus 71%) fleeces compared to those from uncoated animals. Coats did not affect any other measured trait. Fiber and meat production were most expensive in the RF system and least expensive in the P system. Even with coats, mohair produced in the FL and P systems was not clean enough to qualify for the hand spinner niche market. The RF coated fleeces exhibited exceptional visual cleanliness that permitted them to be sold for several multiples of the prevailing mohair commodity price.

The potential for winter supplementation to increase juniper intake by goats on rangelands in the Edwards Plateau region of Texas was assessed in two experiments. The first experiment evaluated the effect on juniper intake of either no supplementation (negative control) or supplementation with corn, alfalfa, or cottonseed meal fed at an isonitrogenous protein level of 1.5 g · kg body weight−1 for 12 days. Redberry juniper (Juniperus pinchotii Sudw.) consumption by individually penned Spanish, Boer × Spanish, Spanish × Angora, and Angora goats was measured on days 11 and 12. Each goat received each supplement in a complete 4 × 4 Latin square design. Juniper intake increased for goats supplemented with alfalfa and cottonseed meal (P = 0.001), but not for those supplemented with corn (P = 0.944). Boer × Spanish goats did not differ in levels of consumption (P = 0.085) from the other breeds. A second study investigated the effect of either no supplementation or soybean meal supplementation on juniper...

An innovative lamb-feeding facility with a raised-slatted floor (RF) was designed and built for the purposes of concurrently producing high-quality, high-value wool and large, lean lamb carcasses. A ration was formulated to provide a low rate of gain in order that lambs attained slaughter weight (59 kg) when they were approximately 12 month of age because a 12-month fleece is a prerequisite for high value in the targeted hand spinning niche wool market. A study was conducted to compare production and quality of wool and meat and associated economics of feeding lambs housed in the RF system versus two conventional systems, a feedlot (FL) and supplementation on pasture (P). For this purpose, 143 5-month-old, male, castrated Rambouillet lambs were obtained and assigned to a production system. Half of the lambs in the RF and FL systems were fitted with protective coats. As planned, daily gain was greater and days to slaughter were less in the FL versus the RF system, with P being intermediate. Final shorn bodyweights were similar in each system, but RF dressing percentage was considerably lower than those in the FL and P systems. This anomaly was likely due to the greater gut fill of RF lambs compared to those in the other two systems. Leaner carcasses were produced in the RF and P systems compared to the FL system. The RF fleeces were heavier than those produced in the FL system with P fleeces being intermediate. Average fiber diameter and variability did not differ among treatments. Though considerably longer than FL staples, wool produced in the RF system was more uniform (CV%) in terms of fiber diameter measured along the staple length. Importantly, coats did not affect rates of gain in either the FL or RF system and had minimal effects on other measured properties. Coated fleeces were only arithmetically higher yielding than uncoated fleeces (55.2% versus 53.4%), but the coated fleeces were visually cleaner and brighter than uncoated fleeces, which is very important for the targeted niche market. Price obtained for coated RF wool sold into a niche market was five times higher than conventionally marketed FL and P wool prices. Net income per head was negative for all three systems (−US$ 0.11, −US$ 2.20, and −US$ 5.57 per head for FL, P, and RF, respectively). In this study, the substantially higher returns from the niche wool market did not compensate fully for the extra cost of production and the extra effort required for niche marketing.

The effects of breed, sex, and age of goats on fecal near-infrared reflectance spectroscopy-predicted percentage juniper in the diet were investigated, as were spectral differences in feces from goats differing in estimated genetic merit for juniper consumption. Eleven goats from each breed, sex, and age combination, representing 2 breeds (Angora and meat-type), 3 sex classifications (female, intact male, and castrated male), and 2 age categories [adult and kid (less than 12 mo of age)] were fed complete, pelleted rations containing 0 or 14% juniper. After 7 d on the same diet, fecal samples were collected for 3 d, and the spectra from the 3 replicate samples were averaged. Fecal samples were assigned to calibration or validation data sets. In a second experiment, Angora and meat goats with high or low estimated genetic merit for juniper consumption were fed the same diet to determine the effect of consumer group on fecal spectra. Feces were scanned in the 1,100- to 2,500-nm range with a scanning reflectance monochromator. Fecal spectra were analyzed for the difference in spectral characteristics and for differences in predicted juniper in the diet using internal and independent calibration equations. Internal calibration had a high precision (R(2) = 0.94), but the precision of independent validations (r(2) = 0.56) was low. Spectral differences were affected by diet, sex, breed, and age (P < 0.04). However, diet was the largest source of variation in spectral differences. Predicted percentage of juniper in the diet also showed that diet was the largest source of variation, accounting for 95% of the variation in predictions from internal calibrations and 51% of the variation in independent validations. Predictions from independent calibrations readily detected differences (P < 0.001) in the percentage of juniper in the 2 diets, and the predicted differences were similar to the actual differences. Predicted juniper in the diet was also affected by sex. Feces from goats from different juniper consumer groups fed a common diet were spectrally different, and the difference may have resulted from a greater intake by high- compared with low-juniper-consuming goats. Fecal near-infrared reflectance spectroscopy predictions of botanical composition of diets should be considered an interval scale of measurement.

The objectives of this study were to describe and compare means and measures of variability of fiber characteristics and fiber production between genetically furred and furless rabbits and among classes of furless rabbits. An F1 generation of rabbits was produced by mating New Zealand White does to a rare, furless Mini Lop buck. All F1 offspring had normal coats of fur. Inter se random matings of the F1 stock (barring full-sibling matings) were made to produce the F2 generation that consisted of approximately 75% furred and 25% furless progeny. Furless animals were further subjectively classified into 3 distinct classes (1 to 3) having increasingly more fur. In yr 1, 17 furred and 20 furless rabbits (age 28 to 49 d) were randomly assigned to growing pens, and in yr 2, 17 additional furless and 9 additional furred rabbits were included to increase the size. After 6 wk, the rabbits were weighed, and a measured area of fur (approximately 20 cm2) was shorn from the left flank of each rabbit. This fiber was weighed and measured for staple length, fiber diameter, prickle factor (% of fibers > 30 microm in diameter), and fiber curvature. Fiber production per unit area of skin was calculated and fiber production per animal was estimated. In yr 2, all of the furless and 2 of the furred rabbits were shorn over their entire bodies to obtain direct measurements of total fur weight. Furless rabbits were 9% heavier (1,941 vs. 1,783 g of BW, P < 0.01) and produced approximately 90% less fiber per unit area of skin than furred rabbits (1.74 vs. 15.83 mg/cm2, P < 0.01). The fibers from furless rabbits were shorter (1.54 vs. 2.56 cm, P < 0.01) and coarser (15.8 vs. 14.5 microm diameter, P < 0.01) than those from furred rabbits and exhibited greater prickle factor (11.3 vs. 3.5%, P < 0.01) and curvature values (47.5 vs. 38.5 deg/mm, P < 0.01). Class 3 furless rabbits were heavier than rabbits of classes 1 and 2 (2,075 vs. 1,817 and 1,981 g of BW, respectively, P < 0.05). Means for actual total fiber production per animal for classes 1 to 3 were 0.64, 2.07, and 8.68 g, respectively, compared with 23.0 g for furred rabbits (P < 0.01). Although some similarities were present, several of the correlations involving fiber properties and BW were substantially different (e.g., BW vs. staple length and fiber diameter vs. weight of fiber per unit area) for furred and furless groups. These results, and those reported elsewhere from a series of experiments, support the potential for production of furless rabbits in arid and tropical environments.

A study was conducted to establish a comprehensive profile of US Huacaya Alpaca fiber characteristics that could be useful for educational, promotional, policy, selection, and breeding purposes. Specifically, the means, distributions, and ranges of 23 fiber characteristics and body weight of a representative sample (n = 585) of US Alpacas were measured or calculated using internationally accepted objective test methods. Animals in specified age groups and of known sex representing six geographical regions in the USA were weighed and sampled in approximate proportion to their population density in the respective regions. Fiber samples were shorn from the mid-side of the Alpacas, representing female, male, and castrated male registered animals in the three age categories: 1- and 2-year-old and adult Alpacas. Each sample was measured for mean fiber diameter, prickle factor, comfort factor, mean fiber curvature, medullation (white and light fawn samples only), laboratory scoured yield, mean staple length, mean staple strength, position of break, and resistance to compression. In addition, yellowness and brightness were measured on the white samples and color differences were measured on the colored samples using a colorimeter. With one exception (laboratory scoured yield), the measured characteristics exhibited considerable variability. The only difference in fiber characteristics that was attributable to sex was mean staple strength. Males produced stronger fibers than females. In contrast, differences due to age were apparent for all but two of the measured traits, these being coefficient of variation of staple length and resistance to compression. Compared to wool of comparable fineness, the Alpaca was shown to be higher yielding, more heavily medullated (a distinctive feature of Alpaca), longer, and considerably stronger. Resistance to compression was invariably lower for Alpaca compared to wool of comparable fiber diameter likely due to the lower levels of crimp in the Alpaca fibers.

An experiment was designed to evaluate the effects of five sire breeds (Dorset, Finnsheep, Romanov, Texel, and Montadale), two dam breeds (Composite III [CIII] and northwestern whiteface [WF]), and three shearing seasons (December, February, and April, corresponding to August, October, and December breeding seasons) and their interactions on wool and other characteristics of F1 ewes. Fleeces were collected and characterized from six 2-yr-old F1 ewes representing each of the 90 sire breed x dam breed x shearing season x year (three) subclasses. Characteristics measured objectively were grease and clean fleece weights, clean yield, mean fiber diameter and SD, and mean staple length and SD. Visual assessments of fleece color were also made. Data collected on the F1 ewes were analyzed using a mixed model analysis of variance procedure. The model included fixed effects of year of birth, sire breed, dam breed, shearing season, six two-way interactions, and the three-way interaction of sire breed x dam breed x shearing season. The random effect of individual sire within year of birth x sire breed was also fitted. Texel- and Montadale-sired ewes produced more clean wool (P < 0.05) (approximately 0.24 kg) than Dorset-, Finnsheep-, and Romanov-sired ewes. Texel-sired ewes produced the coarsest wool (28.7 microm) (P < 0.05), whereas Romanov-sired ewes produced the finest (24.9 microm) and longest (9.12 cm) fleeces (P < 0.05). Ewes from WF dams produced more and finer wool (0.15 kg and 2.7 microm) than ewes from CIII dams (P < 0.001). Ewes shorn in December produced more, coarser, and longer wool (P < 0.05) than those shorn in February and April. This trend in wool production is opposite to that in conception rate (reported previously). Romanov-sired ewes produced the lowest percentage of white fleeces (62.6%), whereas Dorset-sired ewes produced the most (P < 0.001) white fleeces (96.3%). Estimates of heritability were calculated for grease and clean fleece weights (0.36), percentage of clean yield (0.31), average fiber diameter and SD (0.86 and 0.42, respectively), and average staple length and SD (0.49 and 0.00, respectively). Although necessary for a thorough evaluation of these 10 types of crossbred ewes, it is estimated that wool income would only constitute a small portion (1 to 5%) of overall income from sheep of this type.

The Optical Fibre Diameter Analyser (OFDA) instrument is based on automatic image analysis technology and was recently introduced to provide a rapid, accurate measurement of average fiber diameter (AFD) and diameter distribution (SD) of textile fibers. Experiments were conducted with wool and mohair in various physical forms (top, core, and staple) to compare results produced by the OFDA with two other methods of determining fiber diameter parameters: the standard projection microscope (PM) method as described by the American Society for Testing and Materials (ASTM) and the Peyer Texlab FDA 200 System (FDA200). The results show that the OFDA fiber diameter measurements were very closely related to PM measurements, and the OFDA partially overcame one shortcoming of the FDA200, overestimation of SD. The results suggest that the OFDA is a promising system for rapid and accurate evaluation of fiber diameter and its distribution.

Eighty-one mixed-age (2 to 8 yr old) Rambouillet ewes (58.5 kg, SD 5.9 kg) were randomly assigned to three treatment groups that contained similar numbers to study the effects of wool skirting on clean yield, fiber diameter, and prices received for fine wool. The sheep were managed as a single flock on an experimental ranch close to Barnhart, TX during the 4-yr study. Two fleece-skirting techniques (SK1 and SK2) were compared with a control procedure in which fleeces were not skirted before packaging (original bag, OB method). Skirted wools were higher yielding (P.05) and contained less vegetable matter (P.05) than skirts. However, clean yield and vegetable matter content of skirted and OB wools were not different (P.05). Weight-averaged prices received for grease wool from the SK1, SK2, and OB treatments over the 4-yr period were 4.49, 4.36, and 3.83 $/kg, respectively. Prices received for both types of skirted wool plus skirts were higher (P.05) than prices received for OB wool.

Eight castrated male Angora goats were used in a repeated, simultaneous 4 x 4 Latin square designed experiment to evaluate metabolic and mohair responses of Angora goats to sulfate supplementation. Goats had ad libitum access to isonitrogenous diets containing a .16 (basal), .23, .29, or .34% S (DM basis), which yielded N:S ratios of 12.7, 8.3, 6.8, or 5.5:1. Feed intakes were not affected (P greater than .20) by dietary S level. Quadratic increases (P less than .05) to S supplementation were observed in grease and clean mohair production, grease and clean staple strength, and staple length. Mohair diameter, med fiber, kemp fiber, S, and cysteine contents were not affected (P greater than .05) by supplemental S. Averaged across the prefeeding, 2, 4, and 6 h postprandial sampling times, ruminal pH, ammonia N, total S, organic S, protein S, and plasma urea N and organic S concentrations were quadratically increased (P less than .05) by supplemental S. Ruminal sulfate S, total sulfide S, and plasma sulfate S were linearly increased (P less than .05) by supplemental S. Retention of N and mohair S yield exhibited quadratic increases (P less than .05), but S retention exhibited a linear increase (P less than .001) with increased S intake. Calculated by regression, the optimum dietary S concentration for maximum clean mohair production was .267% of dietary DM for a N:S ratio of 7.2:1, suggesting that the National Research Council N:S ratio of 10:1 is inadequate for Angora goats. The optimum level of digestible S was calculated to be .18% of the diet DM.

Experiments reporting incidence of medullated fiber in mohair were reviewed. Genetics, nutrition, season and disease have been implicated in affecting medullation levels which are variable within fleeces. To measure medullation accurately, representative samples of the whole fleece must be measured. Subjective medullation scores are of limited value since they are not highly correlated with actual measurements of medullation. Progress towards reducing medullated fibers in mohair is possible by selection of animals older than one year of age. The environmental factors nutrition, geographical location and disease have minimal effects on medullated fiber production. Effects of season and management on medullation are not clear.

In response to increasing commercial interest and the high market value of qiviut (the downy underwool of the muskox), we have employed standards and measurements used in the wool and cashmere industries to describe qiviut fiber characteristics. Fleece samples (qiviut with guard hair) were shaved from the midshoulder of 299 wild muskox hides of known sex and age (1, 2, 3, and 4+ yr) during the Banks Island, Canada, muskox harvest in November 1997. Samples were analyzed for fiber diameter distribution of raw fiber and qiviut, scoured and qiviut yields, and lengths of guard hair and qiviut fiber. We found a sex x age interaction for average fiber diameter (AFD) in raw fiber (P= 0.002) and qiviut (P0.001) only. Adult males had significantly coarser AFD than females (21.5 microm, males vs 20.1 microm, females and 18.2 microm, males vs 17.5 microm, females) for raw fiber and qiviut, respectively. Qiviut AFD from yearlings was 1.7 microm finer than the AFD of adult qiviut. Fiber diameter distribution (SD) decreased with age in the raw sample (P0.003) and qiviut (P0.001) and qiviut SD was greater (P0.001) in males than in females. Qiviut theoretical yield (% mass of fibersor = 30 microm) increased (P0.001) with age, and females had higher theoretical yields than males (P0.001). Scoured yield did not vary between sexes in any age class and averaged 93.3%. Qiviut staple length did not differ with either age or sex. In summary, differences between the sexes were small up to the 3rd yr, and these differences were not likely to be of commercial importance. However, considering that AFD is a primary commercial criterion of value, AFD changes from 16.5 microm in yearlings to 18.2 microm in adults and from 17.5 microm in adult females to 18.2 microm in adult males would be expected to result in significant differences in commercial value.

We conducted three experiments to evaluate the Optical Fibre Diameter Analyser (OFDA) for estimating medullation (med [M], kemp [K], and total [T] medullated fiber content) in mohair and wool produced by Angora goats and sheep, respectively. Medullation can be a beneficial characteristic in certain types of wool, but it is highly undesirable in mohair and apparel wools. Current techniques for evaluating medullation in animal fibers are laborious, slow, and expensive. The OFDA had been modified by the manufacturer to measure fiber opacity distribution, a characteristic known to be indicative of medullation in white fibers, and was capable of providing such measurements in a very short time. Measurements made on magnified fiber images produced with a projection microscope (PM) were used as a reference for M, K, and T in fiber samples. An initial experiment with 124 mohair samples (T = .10 to 9.10%) seemed to indicate that OFDA estimates of M, K, and T were only poorly correlated with corresponding PM values (r2 = .5409, .1401, and .5576, respectively). However, a second experiment using wool and mohair samples containing a wider range of medullation (T = .58 to 26.54%) revealed that OFDA estimates of M, K, and T for wool were highly correlated with PM measurements (r2 = .9853, .9307, and .9728, respectively). Evidence was also obtained indicating that the low r2 values associated with mohair relationships were likely due to a combination of factors: 1) high variation among the standard PM measurements and 2) the relatively low M, K, and T contents of the mohair samples compared with wool. In a third experiment, greater accuracy was obtained in the PM measurements by evaluating many more individual fibers per sample (10,000). In this case, OFDA estimates of M, K, and T for mohair were highly correlated with corresponding PM measurements (r2 = .8601, .9939, and .9696, respectively). However, the two sets of linear regression equations obtained for wool and mohair were somewhat different, indicating that separate calculations should be used to estimate PM measurements from OFDA data. In conclusion, it was demonstrated that the OFDA instrument is capable of providing relatively fast, accurate, and potentially less expensive estimates of medullated fiber characteristics in mohair and wool.

Mohair from Angora goats has been produced in the United States since the introduction of these animals from Turkey in 1849. Cashmere on Texas meat goats was reported in 1973, but domestic interest in commercial production did not occur until the mid-1980s. Since 1982, the average prices of U.S.-produced mohair and cashmere (de-haired) have ranged from $1.81 to $9.48/kg and approximately $55 to $200/kg, respectively. However, return to producers from mohair has been relatively constant, averaging $10.21/kg, due to the federal incentive program. Because this program is scheduled to terminate with final payment in 1996, the future of mohair profitability is questionable. Prospects for expanded mohair and cashmere production and processing in the United States are influenced by numerous interacting factors and potential constraints. These include the prospect that the goat and textile industries may no longer be profitable in the absence of clear government policies. Although selection may have slightly increased fiber production by Angoras (long term) and domestic meat goats (short term), availability of genetic resources may prove to be a constraint to increased fiber production by cashmere goats and improved meat production by both types of goat. Land resources are plentiful unless new government policies prohibit goats from vast tracts of rangeland and forest because of environmental concerns. Future demand is an unknown, but with increasing world population and affluence, prospects for long-term improved demand for luxury fibers seem good. Competition from foreign cashmere growers is expected, whereas, in the short term, mohair production overseas is declining. However, increased processing of cashmere in its country of origin is expected to result in shortages of raw materials for European and U.S. processors. The amount of scouring, worsted, and woolen equipment in the United States is adequate to accommodate major increases in domestic processing of goat fibers. However, the absence of specific processing knowledge and skills may be constraints. Similarly, the absence of acceptable small-scale dehairing equipment for cashmere will limit cashmere processing on a cottage industry scale. Purely practical considerations such as the effects of predation and cost of fencing could become major constraints to expanding the goat fiber industry. Likewise the success (or lack thereof) of industry promotion of fiber and goat meat could be an overriding factor. To emerge from the uncertainty of erratic raw material prices and to better control profitability, domestic goat-fiber producers are encouraged to consider innovative, cooperative, retained ownership business ventures that will permit them to profit-share up to the retail level.

Two hundred castrated male Angora goats (18 mo of age) were divided equally between rangeland sites in the oak savannah of the Edwards Plateau (EP) and the mixed-brush shrublands of the South Texas Plains (STP) for 5 yr to study influence of environment and age on body weight (BW), mohair production, and mohair fiber characteristics. Goats were grazed on rangeland typical of the respective regions and were given typical management that included shearing in February and July or August of each year. Shorn goats were weighed and individual fleeces were measured for grease weight (GFW), clean yield (CMFP), average fiber diameter (AFD), and proportion of medullated fibers, med (MFP) and kemp (KFP). Rainfall and maximum and minimum temperatures were recorded daily at each site. The AFD (P = .01) and its associated SD (P < .001) and kemp levels (P = .03) were all higher at the STP than at the EP site (39.4 vs 37.9 microns, 10.4 vs 11.1 microns, and .80 vs .68%, respectively). Angora goats at EP weighed less (38.1 vs 41.7 kg, P = .03), and sheared less (1.90 vs 2.22 kg, P = .01), finer (36.4 vs 39.3 microns, P < .001), and less kempy (.52 vs .84%, P < .001) mohair at the February shearing than at the August shearing. No seasonal differences in body weight or in mohair production or quality were apparent at STP. The proportions of total variation in grease mohair production (30.6%), CMFP (22.2%), and AFD (15.7%) due to year effects were two to three times greater at STP than at EP. In contrast, year effects were responsible for only a small proportion (2.2 to 4.6%) of the variation in medullated fibers. The effects of rainfall accumulation within specific 6-mo growing periods were positive for BW, GFW, CFW, AFD, SD of AFD and MFP and negative for CMFP and KFP. Only the rainfall effects on SD of AFD and medullated fibers were significant (P < .05). The effects of age were positive for BW (P < .001), CMFP (P = .046), AFD (P < .001), MFP (P = .014), and KFP (P = .084) and negative for GFW (P = .046) and CFW (P = .107). This study documents influence of environment and age of goats on body weight, mohair production, and fiber characteristics.

The objective of this study was to compare weight and quality of fleeces of different F 1 ewe types produced from breeds with a broad range of fleece types. Weights of 629 fleeces produced during 1988 through 1991 from F 1 ewes that were daughters of Suffolk and Targhee dams and Finnsheep, Combo-6, Booroola Merino, St. Croix, and Barbados sires were recorded. Staple length was measured on the mid-side of each ewe present in 1991. Fleeces shorn in 1991 were sent to a wool marketing organization, and staple length, wool grade, and clean fleece yield were subjectively estimated (n = 220). Mid-side fleece samples were collected from no more than two randomly selected ewes from each subclass (breed of dam-breed of sire-age of ewe) in 1991 (n = 78) and sent to a wool laboratory where fiber diameter, yield, and percentage of colored, med, and kemp fibers were objectively determined. Ewes from Targhee dams produced fleeces with greater weight, greater fiber length, smaller fiber diameter, lower yield, and fewer colored fibers than ewes from Suffolk dams (all differences significant, P

Four experiments were conducted in three separate years to test the utility of near-infrared spectroscopy (NIRS) to predict the clean mohair content of Angora goat fleece. Mohair fleece samples were obtained each year from yearling billies at the conclusion of the Angora Goat Performance Test conducted at the Texas A&M University Research Station, Sonora. In Exp. 1 (n = 293) and Exp. 2 (n = 256), fleeces were scanned with a Pacific Scientific (Silver Spring, MD) near-infrared spectrometer fitted with a fiber-optic probe, and calibrations were developed for clean mohair content. In Exp. 3, 59 mohair fleeces collected at the Texas A&M Research Station in San Angelo were sampled four times each. Each sample was scanned with the same spectrometer in reflectance mode fitted with a transport mechanism. This mechanism allowed the instrument to scan a 15-cm2 segment of the fleece sample. Conventional procedures to determine reference values for mohair yield, vegetable matter content, fiber diameter, and percentage of medullated and kemp fibers were conducted. Prediction equations were developed that related NIR spectra to reference values for yield and diameter parameters and were used to predict mohair characteristics for each fleece sample. The predicted and reference values were subjected to a simple analysis of variance to determine variation within and across samples. In Exp. 1, mohair base was related to NIR spectra with R2 = .46 and standard error of calibration (SEC) = 2.84%. In Exp. 2, similar repeatability errors for mohair base could be obtained for both reference- and NIRS-derived values. Fiber diameter and medullated fibers were poorly related to NIR spectra. When samples were scanned using the transport mechanism (Exp. 3), R2 and SEC were .82 and 1.19% for mohair base and .93 and .98 microm for fiber diameter, respectively. The CV for mohair base and diameter were 1.0 and 1.4%, whereas those for predicted mohair base and diameter were 1.4 and 3.4%, respectively. The increased variation within samples for predicted values represents sampling error and lack of fit between NIRS and the laboratory determined values. When the samples from Exp. 1 and 2 were rescanned with the NIRS transport (Exp. 4), R2 and SEC were .79 and 2.03% for mohair base and .52 and 3.49 microm for fiber diameter. The fiber optic probe would facilitate real-time analysis on the shearing floor, but our data indicate that the spectral limitations so far are too severe. A large sample device such as the transport gave excellent results for predicting mohair base and fiber diameter.

We evaluated the effects of replacing some soybean meal (SBM) protein with fish meal (FM) protein in diets adequate and slightly deficient in CP, with or without .75% sodium bentonite (NaB) on performance and ruminal and blood metabolites of individually fed Suffolk lambs. Diets were based on corn, SBM, and cottonseed hulls. In Exp. 1, five lambs were assigned to each of the three dietary treatments (11% CP with 3% FM, 13% CP with 0 or 3% FM). Lambs fed diets that contained 11% CP with 3% FM or 13% CP with 0% FM had similar DMI and ADG. Gain and feed efficiency were slightly improved (P = .18) by the 13% CP diet with 3% FM. In Exp. 2, 32 lambs were assigned to four dietary treatments (13.5% CP of DM) in a 2 x 2 factorial arrangement (0 or 3% FM, and 0 or .75% NaB on an as-fed basis). The DMI and ADG were increased (P < .05) by FM and NaB supplementation. Interactions (P < .05) revealed that NaB increased DMI, ADG, gain per feed (g/kg of DMI), and plasma urea N concentration in the absence of FM but not in the presence of FM in the diet. Neither FM nor NaB influenced (P = .25) wool growth. Total ruminal VFA were increased (P < .06) by FM and NaB. Differences in mineral content of phalanx bone, liver, and kidney were small and may be related to the mineral content of diets and the effect of NaB on mineral solubilities. Similar DMI and ADG of lambs fed FM and NaB separately and in combination suggest that their beneficial effect is not additive.