**5. Carcass quality**

Diet

Intrinsic

270 Goat Science

Extrinsic

Species Breed or crossbreed Individual, genetics Gender

sensory qualities and veracity between the written and the reality [21].

**4. Main factors that affect carcass and meat quality in goat**

Those, as it is compiled in **Figure 1**, can be classified as intrinsic or extrinsic [22].

Behavior

Management Facilities Production system

Post slaughter

Age and weight at slaughter

Additives

Weaning, type and age

Pre-slaughter Transport

Slaughtering Stress

Consumption Cooking

**Figure 1.** Main factors that modified carcass and meat quality in goat. *Source*: Adapted from Ref. [22].

Commercialization and Cutting

Fasting period Management

Freezing, storage conditions

Milking period, including dam´s milk or milk replacer characteristics.

Physical and chemical characteristics of the ration

To determine quality in relation to meat, we should focus on a specific market [21]. Meat quality needs studies in depth, being a complex topic which presents a lot of questions and aspects to be dealt both, in general (animalism, sustainability, and human health) and with the goat meat in particular (habits, prices, problems of availability and a lack of culture about its specificities and own characteristics). Some of these points (all related with the culture, information, and adaptation to some tendencies of the new markets) could be satisfied with information and adequate labels. The label is the industry and producers' way of communicating directly with the consumer. It should be attractive with a good design, and if possible interactive, providing information on the product's origin and background, its nutritive and

At the end, increasing demand and improving marketing for meat should entail increased production, which must be worthwhile for producers, sustainable for the planet, economically profitable for the production chain, of healthy quality, as well as affordable for consumers [21].

There are several factors that affect the final quality of the product related to carcass and meat.

Due to the high quantity and variability of factors, only some of them will be discussed in the current chapter, those which usually produce more variations. Thus, as intrinsic factors,

Blooding

Ageing Conservation method Processing

Habits

Carcass quality parameters are mainly divided on those that affect morphology, as conformation and morphological measurements, and those related to composition as commercial cuts, fatness score or tissular or chemical composition. Tissular composition is usually obtained as percentage of tissue components from the complete carcass or from specific commercial cuts after a standard cutting and dissection [10, 23].

Carcass traits, such as the conformation as well as fat distribution within the carcass, have a great importance in meat production, because of their economical implications. The proportion of high value cuts is an indication of its overall value, having, some carcasses attributes concerned with the quantity of saleable meat, significant implications on the technological properties of the meat, i.e., the morphology of some specific muscles and cuts [24].

#### **5.1. Weight, conformation and morphological measurements**

Average carcass weight differs depending on the continent or country considered, being 12 kg a world average, and 10 kg for Europe or Spain [1]. Carcass performance on suckling kids of 6–10 kg of life weight can present values between 60 and 65%, because in young animals, only skin and white offals are excluded. In old animals, head and red offals (liver, hearth, spleen, lungs, etc.) are also excluded, presenting a carcass performance of around 50%.

Conformation is used to describe carcass morphology and the visual impression that the different categories produce on the observer [25]. It can be assessed in a comparative way with photographic models, or using measurements based on different anatomical points. For goat species, it does not exist an official classification system of carcass quality, as happens in other ruminants (European System SEUROP for conformation), although some authors have done some proposals [23, 25, 26]. In Spain goat, carcass is classified by animal age as: suckling kid (younger than 1.5 months), young goat (between 1.5 and 6 months of age), and adults (older than 6 months).

Some studies have showed that carcass quality can differ significantly among **breeds**, but differences mainly depend on the criteria used in the comparisons (same weight, same age, or same proportion of mature weight). The results will be different depending on the comparative criteria employed.

For example, at commercial **slaughter weights**, unweaned kids from dairy or meat breeds reared on their dam's milk, following the local husbandry practices that differed significantly in conformation notes and morphology variables [24]. Average carcass weights ranged from 4.38 kg (dairy breed) to 6.56 kg in some meat breeds. Also, products from dairy breeds presented lower conformation (1.70 in a 15 points scale: from 1 poor: poorly muscled carcasses of inferior shape, to 15: excellent, carcasses of outstanding shape) than those from meat breeds.

Related to kid morphological measurements, when data from Ref. [24] were covariated by the carcass weight, smaller differences were appreciated between dairy and meat purpose animals. Thus, some meat breeds presented the longest pelvic limb, but dairy or meat breeds did not statistically differ either on carcass external length, buttock width or chest depth, showing small differences in morphology, independently of their main aptitude. This applies to the most local breeds, which are not meat specialized as Boer, at young slaughter ages.

According to Ref. [10], carcass in small ruminants can be divided into five main regions corresponding to different commercial cuts: leg, ribs, flank, shoulder, and neck. Some results obtained from several studies with cold carcass weights from 3.2 to 16.0 kg are compiled in **Table 1**, being the variability mainly dependent on the studied breed and slaughter weight. According to allometric coefficients [32], when the weight of an animal increases, there is a decrement in the percentage of bone and an increment in the percentage of fat, being the muscle kept almost constant. Early developed cuts are the leg and shoulder, being ribs and

Carcass and Meat Quality in Goat

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http://dx.doi.org/10.5772/intechopen.72095

Tissue composition highly affects commercial quality of the carcass. As happens in other species, as ovine, consumers pay the same price for fat, muscle, and bone, all inclusive in the commercial cuts. Due to this, fat composition is an important factor to consider. It has been reported a great variation on the composition between goat **breeds** [10, 24]: muscle between 69 and 50%, 34–11.8% for bone (a high rate correspondent to young animals), and a percentage of fat between 23.7 and 5%, that could be considered, in general, as low, but it depends of the age, breed and, obviously, fatness score. A dairy breed such as Murciano-Granadina presents the lowest subcutaneous fat percentage, although not different from the local meat purpose breeds, reflecting the tendency for dairy breeds to store more visceral than carcass fat. This visceral deposit has been described as precocious, and it might develop quicker because of the high nutritional level of dairy kids that results from their high dam's dairy production

In Ref. [33], it has been described that natural **suckling** gives higher fatness score and weight of renal fat, compared to kids fed with milk replacer. These results suggest a better assimilation of the natural than artificial milk, although it could also be associated with differences in

On meat aptitude goats, Ref. [27] found a stronger effect of **age** or **final body weight** than **gender**. With the increase of body weight (carcass weight from 4 to 8 kg), fat percentage increased 4% and bone percentage decreased the same amount, having females almost 2% points more of fat and less of bone. No differences in muscle percentage were reported. Consequently,

flank the late developed cuts [27].

potential [24].

composition between milks.

Source: Adapted from Ref. [27].

relation muscle/bone was better for female than male kids.

**Cut Variability (%)** Leg 33.6–26.4 Rib 32.5–21.7 Flank 13.6–9.5 Shoulder 25.7–17.9 Neck 12.6–7.4

**Table 1.** Percentage of different commercial cuts on goat carcasses.

According to data compiled by [27], which show more than 60 different **commercial types** from several locations around the world, age, and live weights, differences between breeds on carcass yield are associated to the final size of the breed, degree of fatness, and aptitude. The lowest performances have been reported in animals of 120–180 days of age, from Chilean Creole breed, with a 45.1% carcass yield [28], and the highest at young Gigertana kids of 25 days of aging with a 70.6% carcass yield [29]. On the other hand, from a commercial point of view, an increment on slaughter weight from 4 to 6 kg may not improve cold carcass yield in Serrana meat breed [27].

**Age** and, consequently, maturity are the most important factors that modify carcass characteristics [30]. Final carcass weight increased on the meat purpose breed Serrana in kids from 10 to 40% of the final adult weight (FAW); however, the performance of 20 and 30% were lower (46.2–46.6% respectively) than those obtained at 10% (51.4%) or 40% (47.9%) of the FAW. On the same study [30], the **gender** had a significant effect on live and carcass cold weights; however, no differences were reported on carcass yield. In Ref. [31], it was found that males presented the greatest weights and average daily gains related to females, especially when came from 3 to 5 years old animals, as well as in single born animals and in autumn.

Different breeds produce differences in morphological measurements ranging thoracic depth from 15.7 cm to 31.4 cm or buttock perimeter from 42.6 to 53.0 cm, being not homogenous the effect of the gender on those variables [27]. Also, results [27] showed that an increment in slaughter weight also presents an increment in morphological measurements of the carcass, which improve carcass compactness index (carcass weight/length carcass), although without effect on leg compactness.

#### **5.2. Carcass composition and fatness**

For fatness score, a classification has been developed with a 5 points scale from 1 (very lean or very low fat cover) to 5 (when the carcass is completely covered) [25].

**Breed** has been described as an important effect in composition and fatness. Related to the fatness score described in [25], a Spanish meat breed such as Blanca Celtibérica presents the highest fatness score [24], because it is normally consumed at heavy **slaughter weights** (6.56 kg cold carcass weight-CCW). However, within suckling animals (the most consumed in Spain), some dairy breeds (Murciano-Granadina) show higher scores (highest fatness) than local meat purpose breeds, even when those parameters are covariated by CCW, showing their highest precociousness.

According to Ref. [10], carcass in small ruminants can be divided into five main regions corresponding to different commercial cuts: leg, ribs, flank, shoulder, and neck. Some results obtained from several studies with cold carcass weights from 3.2 to 16.0 kg are compiled in **Table 1**, being the variability mainly dependent on the studied breed and slaughter weight.

Related to kid morphological measurements, when data from Ref. [24] were covariated by the carcass weight, smaller differences were appreciated between dairy and meat purpose animals. Thus, some meat breeds presented the longest pelvic limb, but dairy or meat breeds did not statistically differ either on carcass external length, buttock width or chest depth, showing small differences in morphology, independently of their main aptitude. This applies to the most local breeds, which are not meat specialized as Boer, at young

According to data compiled by [27], which show more than 60 different **commercial types** from several locations around the world, age, and live weights, differences between breeds on carcass yield are associated to the final size of the breed, degree of fatness, and aptitude. The lowest performances have been reported in animals of 120–180 days of age, from Chilean Creole breed, with a 45.1% carcass yield [28], and the highest at young Gigertana kids of 25 days of aging with a 70.6% carcass yield [29]. On the other hand, from a commercial point of view, an increment on slaughter weight from 4 to 6 kg may not improve cold carcass yield

**Age** and, consequently, maturity are the most important factors that modify carcass characteristics [30]. Final carcass weight increased on the meat purpose breed Serrana in kids from 10 to 40% of the final adult weight (FAW); however, the performance of 20 and 30% were lower (46.2–46.6% respectively) than those obtained at 10% (51.4%) or 40% (47.9%) of the FAW. On the same study [30], the **gender** had a significant effect on live and carcass cold weights; however, no differences were reported on carcass yield. In Ref. [31], it was found that males presented the greatest weights and average daily gains related to females, especially when came from 3 to 5 years old animals, as well as in single born animals and in autumn.

Different breeds produce differences in morphological measurements ranging thoracic depth from 15.7 cm to 31.4 cm or buttock perimeter from 42.6 to 53.0 cm, being not homogenous the effect of the gender on those variables [27]. Also, results [27] showed that an increment in slaughter weight also presents an increment in morphological measurements of the carcass, which improve carcass compactness index (carcass weight/length carcass), although without

For fatness score, a classification has been developed with a 5 points scale from 1 (very lean or

**Breed** has been described as an important effect in composition and fatness. Related to the fatness score described in [25], a Spanish meat breed such as Blanca Celtibérica presents the highest fatness score [24], because it is normally consumed at heavy **slaughter weights** (6.56 kg cold carcass weight-CCW). However, within suckling animals (the most consumed in Spain), some dairy breeds (Murciano-Granadina) show higher scores (highest fatness) than local meat purpose breeds, even when those parameters are covariated by CCW, showing

very low fat cover) to 5 (when the carcass is completely covered) [25].

slaughter ages.

272 Goat Science

in Serrana meat breed [27].

effect on leg compactness.

their highest precociousness.

**5.2. Carcass composition and fatness**

According to allometric coefficients [32], when the weight of an animal increases, there is a decrement in the percentage of bone and an increment in the percentage of fat, being the muscle kept almost constant. Early developed cuts are the leg and shoulder, being ribs and flank the late developed cuts [27].

Tissue composition highly affects commercial quality of the carcass. As happens in other species, as ovine, consumers pay the same price for fat, muscle, and bone, all inclusive in the commercial cuts. Due to this, fat composition is an important factor to consider. It has been reported a great variation on the composition between goat **breeds** [10, 24]: muscle between 69 and 50%, 34–11.8% for bone (a high rate correspondent to young animals), and a percentage of fat between 23.7 and 5%, that could be considered, in general, as low, but it depends of the age, breed and, obviously, fatness score. A dairy breed such as Murciano-Granadina presents the lowest subcutaneous fat percentage, although not different from the local meat purpose breeds, reflecting the tendency for dairy breeds to store more visceral than carcass fat. This visceral deposit has been described as precocious, and it might develop quicker because of the high nutritional level of dairy kids that results from their high dam's dairy production potential [24].

In Ref. [33], it has been described that natural **suckling** gives higher fatness score and weight of renal fat, compared to kids fed with milk replacer. These results suggest a better assimilation of the natural than artificial milk, although it could also be associated with differences in composition between milks.

On meat aptitude goats, Ref. [27] found a stronger effect of **age** or **final body weight** than **gender**. With the increase of body weight (carcass weight from 4 to 8 kg), fat percentage increased 4% and bone percentage decreased the same amount, having females almost 2% points more of fat and less of bone. No differences in muscle percentage were reported. Consequently, relation muscle/bone was better for female than male kids.


**Table 1.** Percentage of different commercial cuts on goat carcasses.

In general, it could be said that goat carcasses are longilinear and, consequently, they have a poor conformation. Also, they have high muscle and bone percentages and low content of fat, especially subcutaneous fat.
