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Whole cervical and lumbar vertebrae, ribs and femurs from 12 ovine, eight porcine and 14 bovine carcasses and whole cervical vertebrae, ribs, femurs and synsacrums from eight chickens and eight turkeys were removed from animals slaughtered at different chronological ages. Large increases in fat and dry matter with increased age were found in cervical and lumbar vertebrae, ribs and femurs from ovine, porcine and bovine carcasses. In chickens and turkeys, dry matter increased with age but fat in fresh bone remained relatively constant. In all five species dry-fat-free bone decreased in percent nitrogen and increased in ash and calcium as age increased. Percent calcium in bone ash was similar for all age groups of all species except turkeys and for all four bones studied. Calcium to nitrogen ratio increased with age. Significant differences in composition of bones within animals were evident. Rib bones had the lowest fat percentage and femurs had the highest fat and dry matter percentage in cattle and sheep. Ribs, partially because of high ash content, usually contained more dry matter than lumbar and cervical vertebrae. In general, femurs possessed the least nitrogen and the most ash of any of the bones studied. Hydroxyproline content, on a dry-fat-free basis, did not differ significantly according to age or bone in the red meat species. Nutritional value of bone protein from all five species was low when based upon hydroxyproline analysis. Calcium or ash could be useful in studying changes in bone maturity. These bone components could also be used to estimate amount of bone in mechanically deboned meat.

In this trial 63 Western whiteface wether lambs were used in a 2 × 2 factorial design arrangement to study the effects of two dietary protein levels (10.5 and 13.5%) and two dietary energy levels (50:50 and 80:20 ratio of concentrate to roughage) on live traits and carcass composition. All lambs were slaughtered at a constant weight of approximately 60 kilograms.Live traits were affected most by changes in protein and energy levels. Increasing protein levels resulted in higher average daily gains and improved feed efficiencies. As energy content of the diets increased, days on feed increased while feed consumption decreased. Feed efficiency improved as energy levels increased. Preslaughter shrink increased as energy level in the diets decreased. Carcass measurements, quality factors and chemical composition of carcass were not affected by changes in protein and energy levels.Significant interactions between protein and energy levels in the ration were noted for kidney fat weight, percent kidney fat, body wall thickness and yield grade. As percent protein in the diets increased, carcass fat measures increased on the low energy diets but decreased on the high energy diets. As energy level in the diets increased, carcass fat measures increased on the low protein diets but decreased on the high protein diets.

Data were collected on 64 ram and 564 wether and ewe carcasses. Simple carcass measurements were useful in developing equations for estimating percent fat, weight of retail cuts and percent retail cuts. The equation using body wall thickness and fat depth 3.8 cm. from the midline between the 12th and 13th ribs had multiple correlations of 0.72 and 0.87 and standard error of estimates of 2.95 and 3.90 for predicting percent fat in the boneless carcass of ewes and wethers and rams, respectively. Carcass weight, body wall thickness and fat depth 3.8 cm. from the midline between the 12th and 13th ribs had a multiple correlation of 0.84 and a standard error of estimate of 0.34 for estimating kilograms of retail cuts from lamb carcasses. Carcass weight and body wall thickness had a multiple correlation of 0.99 and a standard error of 0.44 for predicting kilograms of retail cuts of ram carcasses. Body wall thickness, kidney weight and fat depth 3.8 cm. from the midline between the 12th and 13th ribs had a multiple correlation of 0.73 and a standard error of 1.47 for estimating percent retail cuts from lamb carcasses. The equations mentioned in this summary indicate that percent fat, percent retail cuts and weight of retail cuts can be estimated without breaking the carcass or by using subjective measurements.

Data were collected on 802 offspring from 58 sire groups. Heritability estimates as calculated by paternal half-sib correlations were generally higher and had lower standard errors than comparable estimates calculated by regression of offspring on sire. Heritability estimates were relatively high for measures of fat, lean and tenderness. Estimates of heritability were relatively low for quality traits. Heritability estimates for wool traits were lower than those reported by previous researchers. The high heritability estimates for traits of carcass merit are encouraging from the standpoint of progress that can be made by selection.

FORTY-THREE wether lambs weighing 50 kg, and 47 wethers and 50 rams weighing 65 and 68 kg, respectively, were used to evaluate the effects of weight and castration on carcass composition, fatty acid composition and palatability. Light wethers (50 kg) were superior in cutability to heavy wethers (65 kg). Heavy rams (68 kg) were superior to heavy wethers (65 kg) in cutability.Percent myristic, palmitic and stearic decreased as weight and age increased and total percent unsaturates increased proportionally. There were no significant differences in intramuscular fatty acids due to castration. Kidney fat from rams contained significantly (P<.05) less 18:0 than that from heavy wethers. Subcutaneous fat from rams contained significantly (P<.05) more myristic and palmitic than that from heavy wethers.Taste panel results indicated that both light wethers and rams were significantly (P<.05) less tender than heavy wethers. However, rams were comparable to light wethers in all palatability traits studied.

1. The reaction of exo-cis-3,6-endoxo-Δ4-tetrahydrophthalic anhydride with amino groups of model compounds and lysozyme is described. 2. Reaction with the ∈-amino group of Nα-acetyl-l-lysine amide gives rise to two diastereoisomeric products; at acid pH the free amino group is liberated with anchimeric assistance by the neighbouring protonated carboxyl group with a half-time of 4–5h at pH3.0 and 25°C. 3. The amino groups of lysozyme can be completely blocked, with total loss of enzymic activity. Dialysis at pH3.0 results in complete recovery of the native primary and tertiary structure of lysozyme and complete return of catalytic activity. 4. The specificity of reaction of this and other anhydrides with amino groups in proteins is discussed.

Twenty-six ram and wether lambs were used to evaluate effects of testosterone on carcass composition, fatty acid composition, flavor and tenderness.Significant differences (P<.05) were observed between treated rams and untreated wethers in thickness, color and firmness of fat. Testosterone enanthate treated wethers and normal rams were remarkably similar in all carcass traits, especially fat thickness, kidney fat weight, fat color and fat firmness. However, the untreated rams gained significantly (P<.05) faster than the treated wethers.Percent 14:0, 16:0 and 18:0 decreased in all treatments as weight and age increased and total percent unsaturates increased proportionally. Greatest changes in fatty acid composition occurred between 57 and 68 kg live weight when lambs were between 7 and 8½ months of age.At 68 kg, treated rams' fat contained significantly (P<.05) more 15:0 and 17:1 and less 16:0 than other groups. Differences in short chain fatty acids (

Data from 802 lambs representing 58 sire groups were analyzed to determine relationships between live and carcass traits. Genetic correlations indicated some antagonism between fleece growth and body growth (weaning weight and A.D.G. on test) for lambs fed to a relatively constant weight.Negative genetic correlations were also found between fleece weights or staple length and traits related to carcass meatiness (longissimusarea and retail cut weight). Genetic correlations between amount of fat and amount of lean were negative. No serious antagonism was apparent between growth rate and carcass desirability. Consequences of negative relationships between important traits were discussed.

EIGHTY-SIX wether lambs were used to evaluate effects of reduced energy intake on carcass composition, fatty acid composition and palatability.Reduced energy intake had a detrimental effect on slaughter weight, carcass weight, longissimusmuscle area, leg conformation score, carcass grade, marbling score, color of lean and yield of both wholesale and retail cuts. Fat thickness and kidney fat weight of the stressed lambs were also reduced.Only minor differences were observed in fatty acid composition of intramuscular, subcutaneous and kidney fat.The diet-stressed lambs received significantly (P<.05) higher scores for tenderness than the control lambs. No differences between stressed and control lambs were found for flavor, juiciness, overall satisfaction or fat flavor.

Several letters to the editor are presented in response to the articles in previous issues which include "The power of aging in the marketplace,"in the November 20, 1971 issue, "Sharper eyes seek the world's resources," in the November 27, 1971 issue and "The Search for data on marijuana."