The Use of Pork from Entire Male and Immunocastrated Pigs for Meat Products—An Overview with Recommendations

Abstract

Due to the strong public initiative in Europe and increased regulator focus to mitigate pain, surgical castration of pigs is being gradually abandoned, while the importance of other sex categories like entire males (EM) and immunocastrates (IC) increases. Although beneficial for animal welfare and economics, their use also brings forward several quality problems. Besides the occurrence of boar taint in EM, these include excessive carcass leanness, softer fat, meat color and pH deviations, inferior water holding capacity and increased meat toughness. In this paper, the raw material differences between the male sex categories and their influence on product quality are reviewed, and possible solutions are presented. Using EM for dried or thermally processed products may result in lower processing yields and inferior sensory quality, which may partially be prevented by applying specific processing adaptations. Immunocastration is a viable solution, especially when prolonging the vaccination to slaughter interval. Low to medium levels of boar taint can be effectively managed in most of the meat products, applying procedures like cooking, microbial inoculation or masking (by spices and especially smoking), while highly tainted material can be valorized only by combining various methods and/or with dilution of the tainted meat.

Influence of Immunocastration on Slaughter Traits and Boar Taint Compounds in Pigs Originating from Three Different Terminal Sire Lines

“…Significant differences ( p < 0.05) between different sire lines in pH 45 were observed (i.e., the highest values in C and the lowest in B); however, no differences could be found between different male categories for this trait. In agreement with the results of this study, the results of the three meta-analyses showed no or very small difference between different male categories in the case of muscle pH, indicating this trait to be without actual practical importance in regard to sex categories [ 7 , 26 , 32 , 65 ]. We also found a significant interaction ( p < 0.001) between the TSL*MC on initial pH values ( Figure 2 A; Table S1 ).…”

“…Similar to the result for animals originating from TSL B, in the investigation of Škrlep et al (2011) [ 43 ] on two types of crossbreds (Duroc and Pietrain sired), drip loss measured after 24 h and 48 h was also influenced by sex and crossbreed type interaction but without any differences between the MCs. The results of individual studies investigating only the sex type as an influential factor are ambiguous; however, generally, no difference between different sex types was found for this trait [ 7 , 32 , 49 ]. It should be noticed that observed drip loss was quite high in all investigated groups; however, this may be more related to the relatively low age of the animals, especially for entire males, which still did not manage to exhibit their full physiological potential at this stage of growth and development [ 71 , 72 ].…”

“…In the same study, it was also reported that EM had higher WBSF values than IC and SC. The results of meta-analytical and several latter studies generally indicate EM as exhibiting the toughest meat [ 7 ]. However, we did not find significant differences between different MCs for this trait.…”

“…Boar taint is described as offensive urine-, sweat- and faecal-like odour and/or taste, attributed to substances skatole and androstenone that are deposited in fat tissue of uncastrated animals [ 6 ]. Besides, EM may prove problematic in terms of more aggressive behaviour [ 2 ] and inferior meat quality accompanied by low-fat saturation (being also important in terms of consumer acceptance and processing aptitude [ 7 ]).…”

Combined Effect of Dietary Protein, Ractopamine, and Immunocastration on Boar Taint Compounds, and Using Testicle Parameters as an Indicator of Success

“…Various approaches have been investigated to control boar taint-related compounds [ 19 ], with gene-editing showing huge potential, but also a rather lengthy timeline before commercial implementation. While some approaches may address decreasing the incidences of boar taint, they do not necessarily address the welfare issues of entire male production, such as aggressive behavior [ 20 ], the meat/product quality issues associated with entire males [ 21 ], or the application of these technologies, such as gene editing, is currently limited in various countries. Thus, commercial interest in the use of immunocastration has increased, which entails vaccinating the animal against its own gonadotropin-releasing hormone (GnRH).…”