specified as minimum for the Good grade may have quality equal to the lower limit of the upper third of the Standard grade and remain eligible for Good.

(d) Standard. (1) Vealers possessing minimum requirements for the Standard grade tend to be very thinly muscled throughout and tend to be very narrow over the back, loin, and rump and very shallow in the twist. Hips and shoulders are very prominent, and the crops, back, loin, rump, and rounds present a very sunken or hollowed-out appearance. They show no evidence of any fat covering. Standard vealers tend to be of low quality. The bones and joints are usually disproportionately large and the hide is either thick or tight and inelastic.

(2) Quality superior to that specified as minimum for the Standard grade may compensate, without limit, for conformation inferior to that specified as minimum for the Standard grade at the rate indicated in the following example: Vealers with quality equivalent to the midpoint of the Standard grade may have conformation equivalent to the midpoint of the Utility grade and remain eligible for Standard. Also, vealers with conformation at least one-third of a grade superior to that specified as minimum for the Standard grade may have quality equal to the lower limit of the upper third of the Utility grade and remain eligible for Standard.

(e) Utility. The Utility grade includes vealers whose characteristics are inferior to those specified as minimum for the Standard grade.

§ 53.124 Specifications for official United States standards for grades of slaughter calves.

(a) Prime. (1) Calves possessing minimum qualifications for the Prime grade tend to be moderately thick muscled throughout. They are moderately wide over the back and loin, and shoulders and hips are usually moderately neat and smoothly laid in. There is a slight fullness or plumpness over the crops, loin, rump, and rounds which contributes to a rather well-rounded appearance. Prime grade calves tend to have a slightly thick fat covering over the back, loin, rump, and upper ribs. The brisket, rear flanks, and cod or udder are moderately full. Prime grade calves usually present a moderately refined appearance.

(2) To qualify for the Prime grade, slaughter calves must possess the mini

mum evidences of quality specified regardless of the extent to which their conformation may exceed the minimum requirements for Prime. However, quality superior to that specified as the minimum for the Prime grade may compensate, without limit, for conformation inferior to that specified as the minimum for Prime at the rate indicated in the following example: Slaughter calves which have quality equivalent to the midpoint of the Prime grade may have conformation equivalent to the midpoint of the Choice grade and remain eligible for Prime.

(b) Choice. (1) Calves possessing minimum qualifications for the Choice grade tend to be slightly thick muscled throughout. They are slightly wide over the back and loin. The neck is slightly long and thin. The loin, rump, and rounds are almost flat and have little or no evidence of fullness. The shoulders and hips are moderately neat and smoothly laid in but may appear slightly prominent. There is a thin fat covering over the back, loin, and upper ribs. The brisket, rear flanks, and cod or udder tend to be slightly full. Choice grade calves are usually moderately smooth and slightly refined in appearance.

(2) To qualify for the Choice grade, slaughter calves must possess the minimum evidences of quality specified regardless of the extent to which their conformation may exceed the minimum requirements for Choice. However, quality which is superior to that specified as the minimum for the Choice grade may compensate, without limit, for conformation which is inferior to that specified as the minimum for Choice at the rate indicated in the following example: Slaughter calves which have quality equivalent to the midpoint of the Choice grade may have conformation equivalent to the midpoint of the Good grade and remain eligible for Choice.

(c) Good. (1) Calves possessing minimum requirements for the Good grade tend to be thinly muscled throughout. They are narrow over the back, loin, and rump and shallow in the twist and have a slightly sunken or hollowed-out appearance over the back, loin, and rounds. Hips and shoulders appear somewhat prominent. There is a very thin fat covering that is discernible only over the back and loin. Such calves may show the heavy bones, thick hide, prominent hips and shoulders associated with

coarseness; or they may show the small bones, tight hide, and angularity denoting overrefinement.

(2) Quality superior to that specified as the minimum for the Good grade may compensate, without limit, for conformation inferior to that specified as the minimum for Good at the rate indicated in the following example: Calves with quality equivalent to the midpoint of the Good grade may have conformation equivalent to the midpoint of the Standard grade and remain eligible for Good. Also, calves with conformation at least one-third of a grade superior to that specified as minimum for the Good grade may have quality equal to the lower limit of the upper third of the Standard grade and remain eligible for Good.

(d) Standard. (1) Calves possessing minimum requirements for the Standard grade tend to be very thinly muscled throughout and are very narrow over the back, loin, and rump, and very shallow in the twist. Hips and shoulders are very prominent and the crops, back loin, rump, and rounds present a very sunken or hollowed-out appearance. There is practically no fat on any part of the animal's body. The bones and joints are usually disproportionately large, and the hide is either thick or tight and inelastic.

(2) Quality superior to that specified as minimum for the Standard grade may compensate, without limit, for conformation inferior to that specified as minimum for the Standard grade at the rate indicated in the following example: Calves with quality equivalent to the midpoint of the Standard grade may have conformation equivalent to the midpoint of the Utility grade and remain eligible for Standard. Also, calves with conformation at least one-third of a grade superior to that specified as minimum for the Standard grade may have quality equal to the lower limit of the upper third of the Utility grade and remain eligible for Standard.

(e) Utility. The Utility grade includes slaughter calves whose characteristics are inferior to those specified as minimum for the Standard grade. SLAUGHTER LAMBS, YEARLINGS, AND SHEEP § 53.130 Market sheep.

The official standards for market sheep, developed by the United States

(d) Lamb. A lamb is an immature ovine, usually under 14 months of age, that has not cut its first pair of permanent incisor teeth.

(e) Yearling. A yearling is an ovine usually between one and two years of age, that has cut its first pair of permanent incisor teeth but has not cut the second pair.

(f) Sheep. A sheep is an ovine, usually over 24 months of age, that has cut its second pair of permanent incisor teeth.

123 FR 9407, Dec. 5, 1958]

§ 53.132 Application of standards.

(a) Grade factors. Grades of slaughter ovines are intended to be directly related to the grades of the carcasses they produce. To accomplish this, these slaughter ovine grade standards are based on factors which are directly related to the quality grades and the yield grades of ovine carcasses. The standards are written so that the quality and yield grade standards are contained in separate sections. The quality grade standards are divided into two sections appllcable to slaughter lambs and slaughter yearlings and sheep. There are five quality grades-Prime, Choice, Good, Utility, Cull-applicable to slaughter lambs, yearlings, and sheep, except that sheep are not eligible for Prime. Also, there are

five yield grades applicable to all classes of slaughter ovines, denoted by numbers 1 through 5, with Yield Grade 1 representing the highest degree of cutability.

(b) General principles. (1) The determination of the carcass grade that the slaughter animal will produce requires the exercise of well-regulated judgment. Each animal presents a different combination of the grade-determining factors. Animals frequently have characteristics associated with two or more grades. Therefore, a composite evaluation of all inherent physical characteristics is essential for accuracy in determining grade.

(2) The accurate determination of the grade of a slaughter lamb or sheep requires handling in addition to visual observation. The length and density of the fleece varies greatly with individuals and the thickness and firmness of the flesh covering of wooled lambs and sheep can only be roughly estimated without handling. The technique used in handling usually varies with the degree of precision in mind as well as the experience of the grader. Experienced graders may find one quick handling satisfactory. This usually consists of placing one open hand over the back and ribs in simultaneous motion. The thumb extends just over the backbone, while the fingers, which are held close together, cover the rib section and pressure is applied very lightly with a slight lateral and forward and backward motion. The generally accepted technique of handling sheep where time permits, and especially when noting slight differences between individuals, is to handle forward from the dock to neck with the open hand, fingers together, laid flat and with a slight lateral motion. Both hands may then be used, one on each side, in a similar manner to determine the fleshing over the shoulders, ribs, and hips. Regardless of the method, considerable experience is necessary in handling lambs or sheep to accurately determine the grade.

(c) Quality grades. (1) The quality grade of a slaughter lamb or sheep is determined by a composite evaluation of two general considerations which influence carcass excellence: Conformation and quality-fatness, maturity, and other indicators of differences in palatability of the lean flesh.

(2) Conformation refers to the general body proportions of the animal and to the ratio of meat to bone. Although primarily determined by the inherent muscular and skeletal systems, it is also influenced by the degree of fatness. Excellent conformation in slaughter lambs and sheep is denoted by a compact, widetopped, thick-fleshed individual that has a large plump leg. Fullness and thickness should be especially evident in the portions of the body producing the more desirable cuts of meat-loin, hotel rack, and leg.

(3) In grading slaughter lamb and sheep, quality of the lean flesh must necessarily be evaluated indirectly from consideration primarily of the quantity, distribution, and type of fat or finish in relation to the maturity of the animal being graded. Limited consideration is also given to such factors as character of bone and smoothness and symmetry of body. Finish is evaluated by noting variations in the fullness and apparent thickness of the fat covering over the back, loin, ribs, and legs. A high degree of desirable finish is evidenced by a firm, smooth layer of fat which is uniformly distributed over the body.

(4) Although the market designation of slaughter lambs and sheep is usually made by classes, the quality standards are intended to apply to all classes without regard to sex condition. However, male animals which have thick heavy necks and shoulders typical of uncastrated males are discounted in grade in proportion to the extent to which these characteristics are developed. Such discounts may vary from less than half a grade in young lambs in which such characteristics are barely noticeable to as much as two full grades in mature rams in which such caracteristics are very pronounced.

(d) Yield grades. (1) The yield grades for slaughter lambs, yearlings, and sheep are based on the same factors used in the official yield grade standards for ovine carcasses. These factors are as follows:

(1) Thickness of fat over ribeye. As the amount of external fat increases, the percent of retail cuts decreases and the numerical yield grade increases. Assum

ing no change in the other factors, each 0.15 inch change in adjusted fat thickness over the ribeye changes the yield grade by a full grade.

(ii) Percent of kidney and pelvic fat. As the amount of these fats increases, the percent of retail cuts decreases. A change of 4 percent of the carcass weight in kidney and pelvic fat changes the yield grade by a full grade.

(iii) Leg conformation grade. An increase in the conformation grade of the legs increases the percent of retail cuts. A change of two full grades in conformation of the legs changes the yield grade by approximately one-third of a yield grade.

(2) When evaluating slaughter ovines for yield grade, each of these factors can be estimated and the yield grade determined therefrom by using the equation contained in the official standards for yield grades of lamb, yearling mutton, and mutton carcasses. However, a more practical method of appraising slaughter ovines for yield grade is to use only two factors normally considered in evaluating live ovines--leg conformation and degree of fatness. In this approach, the degree of fatness largely accounts for the effects of thickness of fat over the ribeye and the percent of kidney and pelvic fat.

(3) The overall fatness of an animal can be determined best by giving particular attention to those parts on which fat is deposited at a faster-than-average rate. These include the back, loin, rump, flank, brisket, cod or udder. As ovines increase in fatness, these parts become progressively fuller, thicker, and more distended in relation to the thickness and fullness of the other parts, particularly the legs. However, since an animal's thickness of muscling also affects the development of its various parts, this also needs to be considered when evaluating the degree of fatness. In thinly muscled ovines with a low degree of finish, the width of the back usually will be greater than the width through the center of the legs. Conversely, in thickly muscled ovines with a low degree of finish, the thickness through the legs will be greater than through the back and the back will be full and rounded. At an intermediate degree of fatness, ovines which are thinly muscled will be considerably wider through the back than

through the leg and will be nearly flat across the back. Thickly muscled ovines that have an intermediate degree of fatness will be about the same width through the legs as through the back and the back will appear only slightly rounded. Very fat ovines will be wider through the back than through the legs, but this difference will be greater in thinly muscled ovines than in those that are thickly muscled. As ovines increase in fatness, they also become deeper bodied because of large deposits of fat in the flanks and brisket and along the underline. In determining yield grade, variations in fatness are very much more important than variations in conformation of the leg.

(e) Other considerations. (1) Other factors such as sex, heredity, and management also may affect the development of grade-determining characteristics in slaughter ovines. Although these factors do not lend themselves to descriptions in the standards, the use of factual information of this nature is justified in determining the grade of slaughter ovines. The ability to make proper allowances for the effects of genetic and management factors on the appearance of grade-determining characteristics must be developed through experience.

(2) Slaughter ovines qualifying for any particular grade may vary with respect to the relative development of their individual grade factors. In fact, some will qualify for a particular grade although they have some characteristics more typical of ovines of another grade. Because it is impractical to describe the nearly infinite number of such recognizable combinations of characteristics, the standards describe only ovines which have a relatively similar development of the various quality and yield gradedetermining factors and which are near the lower limits of quality or yield for the grade. However, examples of the extent to which superiority in quality-indicating characteristics may compensate for deficiencies in conformation, and vice versa, are indicated for each quality grade. In the quality grade standards, the requirements are given for two maturity groups. In the yield grade standards ovines with two levels of muscling are described and specific examples in terms of carcass characteristics also are included. 134 FR 242, Jan. 8, 1969]

§ 53.133

Specifications for official U.S. standards for grades of slaughter lambs (quality).1

(a) Prime. (1) Lambs possessing the minimum requirements for the Prime grade are moderately lowset and blocky and thick-fleshed. They are moderately wide over the back, loin, and rump. Shoulders and hips are usually moderately smooth. The twist is moderately deep and full and the legs are moderately large and plump. They generally present a well-rounded appearance due to a slight fullness or plumpness over the crops, loin, and rump. Relatively young lambs, under seven months of age, tend to have a moderately thin fat covering over the back, ribs, loin, and rump. In handling, the backbone and ribs

are readily discernible. Older, more mature lambs have a slightly thin fat covering over the back, ribs, loin, and rump. In handling, the backbone and ribs are slightly discernible. Prime lambs exhibit evidences of rather high quality. The bones tend to be proportionately small, the joints tend to be smooth, and the body tends to be trim, smooth, and symmetrical.

(2) To qualify for the Prime grade, a lamb must possess the minimum qualifications for finish regardless of the extent that its conformation may exceed the minimum requirements for Prime. However, a development of finish which is superior to that specified as minimum for the Prime grade may compensate, on an equal basis, for a development of conformation which is inferior to that specified for Prime as indicated in the following example: A lamb which has evidences of finish equivalent to the midpoint of the Prime grade may have conformation equivalent to the mid-point of the Choice grade and remain eligible for Prime. However, in no instance may a lamb be graded Prime which has a development of conformation inferior to that specified as minimum for the Choice grade.

(b) Choice. (1) Lambs possessing the minimum requirements for the Choice grade tend to be slightly lowset and blocky and thick-fleshed. They tend to be slightly wide over the back, loin, and rump. The shoulders and hips are usually slightly smooth but may exhibit a slight tendency toward prominence. The

134 F.R. 243, Jan. 8, 1969.

twist tends to be slightly deep and full, and the legs tend to be slightly thick and plump. Relatively young lambs, under seven months of age, have a thin fat covering over the back, ribs, loin, and rump. In handling, the backbone and ribs are moderately prominent. Older, more mature lambs have a moderately thin fat covering over the back, ribs, loin, and rump. In handling, the backbone and ribs are slightly prominent. Choice lambs usually present a moderately refined appearance.

(2) A lamb which has conformation equivalent to at least the mid-point of the Choice grade may have a development of finish equivalent to the minimum for the upper one-third of the Good grade and remain eligible for Choice. Also, a development of finish which is superior to that specified as minimum for the Choice grade may compensate on an equal basis, for a development of conformation which is inferior to that specified for Choice as indicated in the following example: A lamb which has a development of finish equivalent to the mid-point of the Choice grade may have conformation equivalent to the midpoint of the Good grade and remain eligible for Choice. However, in no instance may a lamb be graded Choice which has a development of conformation inferior to that specified as minimum for the Good grade.

(c) Good. (1) Lambs possessing the minimum requirements for the Good grade are moderately rangy and upstanding and thin-fleshed. They are slightly narrow over the back, loin, and rump. Hips and shoulders are moderately prominent. The twist is slightly shallow and the legs are slightly small and thin. Relatively young lambs, under seven months of age, have slightly more than a very thin, uneven fat covering over the back, loin, and upper ribs. In handling, the shoulders, backbone, hips, and ribs are prominent. Older, more mature lambs have slightly more than a thin fat covering over the back, ribs, and loin. In handling, the bones of the shoulders, backbone, hips, and ribs are rather prominent. Lambs of this grade may present evidences of slightly low quality. The bones and joints are usually moderately large, and the body is somewhat lacking in symmetry and smoothness.