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Rising feed costs and recurring feed shortages necessitate the investigation into alternative and underutilized feed resources. Nutritional characteristics of Juniperusspecies are either unknown or limited to leaves and ground material from small stems. Therefore, the objective was to quantify nutritional characteristics, 48-h true IVDMD (tIVDMD), microbial gas production, and secondary compound characteristics of entire woody plant material of 4 Juniperusspecies—Juniperus pinchotii, Juniperus monosperma, Juniperus ashei, and Juniperus virginiana—at immature and mature stages of growth. Immature plants had greater CP concentrations and lower NDF concentrations (P< 0.001) than mature plants regardless of species. Mature plants also had greater (P< 0.001) concentrations of ADF compared with immature plants with the exception of J. virginiana. In general, immature J. pinchotii, J. monosperma, and J. asheihad greater (P< 0.02) tIVDMD and total 48-h and asymptotic gas production than mature plants. Immature J. monospermaand J. pinchotiiplants were more digested (tIVDMD; P< 0.001) than immature J. virginianaand J. ashei, but tIVDMD did not differ in mature plant material across species. Condensed tannins (CT) were greater (P< 0.001) in immature J. pinchotiiand J. asheithan mature plants; differences in CT concentrations among immature species were also detected (P< 0.04). Volatile oil yields were similar across maturity and species with 1 exception: immature J. pinchotiiyielded more (P< 0.02) volatile oil than mature material. Volatile oil composition across species varied and contained a range of 65 to 70 terpene compounds. The dominant terpenes across species were generally greater (P< 0.05) in immature vs. mature plant material with the exception of J. virginiana. Labdane acids were negligible in J. pinchotii, J. ashei, and J. virginianaand greater in J. monosperma(P< 0.001). Ground material from mature juniper species, although inferior in nutritional quality compared with immature plants, is comparable to traditional low-quality roughage ingredients. Given that J. pinchotiihas been successfully fed in lamb feedlot diets, the similarities of J. pinchotii, J. asheiand J. monospermasuggest that all three species have potential to be effective roughage ingredients.

Rib-eye area and fat thickness were estimated on four groups of live cattle, totaling 203, from ultrasonic measurements and subsequently compared with actual measurements taken from a cross-sectional tracing of the musculature and fat in the carcass. The correlation coefficients between live estimated area and actual rib-eye area varied from 0.58 (P<.01) to 0.89 (P<.01). Mean live animal estimates of right vs. left rib-eye areas of two groups of cattle differed less than mean actual area of right vs. left. The correlation coefficients between live estimated fat thickness and actual fat thickness varied from a low of 0.11 (P>.05) to a high of 0.63 (P<.01). A low correlation existed between measurements of a group of cattle in which the spinous processes were scribed during slaughter. Significant relationships existed between the two methods of measuring fat thickness of the three groups in which the spinous processes were not scribed. A significant relationship existed between rib-eye area measured ultrasonically 5 months prior to slaughter and actual area in the carcass but not for fat thickness. The ultrasonic method is a good method for estimating rib-eye area and fat thickness in live cattle.

Two hundred thirty-five live lambs were studied over a 3-year period to determine the usefulness of an ultrasonic procedure for measuring the l. dorsimuscle area and fat thickness. The l. dorsimuscle area in 81% of the lambs was ultrasonically predicted within 0.2 sq. in. of the actual area. A progressive increase in magnitude of correlations was noted during successive years. Ultrasonic and carcass fat thickness measurements taken at the 13th rib and 6-7th lumbar vertebrae were significantly (P<.01) correlated with carcass fat trim. Width and depth of the l. dorsimuscle were both highly correlated with l. dorsimuscle area. The l. dorsimuscle area was correlated with the weight of dissected muscles from the leg and loin. There was no significant difference between area of the l. dorsimuscle from lambs sired by rams of different phenotypic scores.These results indicate that fat thickness and l. dorsiarea of live lambs can be ultra-sonically measured with acceptable accuracy.

Carcasses from 66 cattle 12, 24 and 60 months of age which differed in ante-mortem stress treatment, method of aging and grade were used to investigate differences in tenderness. Tenderness was evaluated at various times during aging by taste panel, chemical and mechanical methods. Tenderness improved during aging, but no differences were obtained between carcasses aged at high and low temperatures for 3 and 15 days, respectively. Steaks from non-stressed steers were significantly more tender than those from stressed steers during the early stages of aging. However, tenderness was similar for steaks from the stressed and non-stressed cattle at the termination of the aging period. The meat from younger cattle was significantly more tender than from older cattle. Panel tenderness values were significantly correlated with Warner-Bratzler shear values, but not with the hydroxyproline content of beef muscle. Significant correlations were also obtained between the conventional Warner-Bratzler shear and a modified “cooked core” shear method.