How Much Meat Should a Lamb Yield?

Carolyn Ihde, Agriculture Educator for Crawford and Richland Counties, University of Wisconsin-Madison
(Previously published online with: Livestock Division of Extension, University of Madison-Wisconsin)

(Figure 1. Lamb Primal Cuts)

Dressing Percentage
To better understand the amount of edible product expected from a grain finished lamb, the first step is understanding the difference in live weight compared to carcass weight. When a lamb (male or female sheep under one year of age) is harvested, certain parts of the animal such as the pelt (hide and wool), feet, blood, and viscera (internal organs) are removed. The post-harvest hanging weight, known as the hot carcass weight, includes the lean (meat), adipose tissue (fat), and bone. Dressing percentage is the difference between live animal and carcass weight and is influenced by factors such as muscle, fat cover and size, to name a few. These factors help determine how much meat the carcass may yield (Table 1).

Table 1. Dressing Percentage Factors

Factor Dressing Percent (%)
Conventional fed 44 – 56
Shorn lambs Average 54
Unshorn lambs Average 52
More finish higher
Grass fed lower
Heavier muscled higher

Carcass Fabrication
During carcass chilling and fabrication, some carcass weight will be lost from the hanging, boning and trimming. The percentage of carcass weight remaining is the “take-home” or retail meat cuts and is called the carcass cutting yield.

Carcass cutting yield is variable and depends on the carcass’s fat thickness (leaner carcasses have increased yields), muscling (greater muscling increases yield), and the amount of bone-in versus boneless retail cuts (boneless decreases yield). (Table 2).

Table 2. Average Carcass Cutting Yield

Cut Type Cutting Yield
Boneless closely trimmed retail cuts 43 -50%
Bone-in regularly trimmed retail cuts 65 – 75%

Requesting closely trimmed and boneless steaks and roasts and/or trimmed, lean ground lamb will result in less pounds of take-home product. This may be advantageous depending on available freezer space and eating preferences. It is important to understand that the amount of edible lean will be the same regardless if the retail cuts are boneless or bone-in. The primary difference will be the inclusion of bone and sometimes some additional fat removal. Choosing to bring home organ meats such as liver, heart, and tongue will also influence the pounds of take-home meat product and increasing the cutting yield.

Primal vs. Retail Cuts
A whole lamb carcass is first divided into five distinctive primal cuts (Figure 1). Each primal cut is then further fabricated into a variety of different retail cuts. Discuss with the meat processer prior to harvest the desired retail cuts (including thickness and number per package). The rough amount of each primal cut (% of the whole carcass) and the possible retail cut choices (from each primal) are displayed in Table 3. Note: selecting one type of cut may impact the ability to select a different retail cut coming from the same primal cut. For example, selecting a bone-in leg roast and center slice leg steaks from one of the lamb legs would not allow the option of getting two whole bone-in leg-of-lamb.

Table 3. Percentage of primal cuts and their retail cuts

Primal (%) Some Possible Retail cuts
Shoulder 23 Arm/Blade Chops

Shoulder chops

Square Cut Shoulder Roast

Boneless Shoulder Roasts

Ground Lamb

Kabob & Stew Meat

Rack/Rib 15 Bone-in Rib Chops

Bone-in Rib Roast

French or Crown Rack

Loin 12 Bone-in Loin Chops/T-bone

Loin Roast

Tenderloin

Leg 33 Sirloin Chops

Bone-in Leg Roast

Boneless Leg Roast (BRT)

Leg Shank Roast

Center Slice Leg Steaks

Bone-In Leg-of-Lamb (Frenched or American)

Boneless Leg-of-Lamb

Kabob & Stew Meat

Foreshank & Breast 12 Foreshank

Ground Lamb

Denver Style Ribs

Further processed products such as bratwursts and other types of fresh and cooked sausages may also be an option to be included in your order.  However, since a small amount of trimmings are generated during lamb fabrication, other lamb cuts and/or non-lamb trimmings (such as pork) are typically added to achieve a desired quantity. Ask your meat processor about any additional products available.

Example Meat Yield Calculations

  • Live Wt. x Typical Dressing Percent = Hot Carcass Wt. 130 lb x 54% = 70 lb
  • Hot Carcass Wt. x (100 – shrink) = Chilled Carcass Wt. 70 x (100% – 3 %) = 68 lb
  • Chilled Carcass Wt. x Carcass Cutting Yield % = Retail Cuts “take-home meat”  68 lb x 70% = 48 lb

Review

  • A carcass is comprised of bone, adipose (fat), and lean
  • The hide, feet, blood, and viscera and sometimes the head are not parts of a carcass
  • Carcass cutting yield is just one factor that influences the amount of take-home product

Important note: Water Loss

  • Hot carcass weight is the weight of a carcass after harvest and prior to chilling.
  • A lamb carcass consists of 70 to 75% water (most in the meat portion).
  • As the carcass chills and ages, water will be lost through evaporation.
  • In just the first 24 hours a carcass can loss 2 to 5% of its initial weight.

References