Effect of vaccination against gonadotrophin-releasing factor on growth performance, carcass, meat and fat quality of male Duroc pigs for dry-cured ham production

The aim of this study was to compare production, carcass and meat quality parameters, boar taint compounds and fat composition of green and dry-cured hams, between immunocastrated (IM), surgically castrated (CM) and female (FE) Duroc purebred pigs (n=75, 138.7±8.27kg). Liveweight and fat and muscle thicknesses were measured and average daily gain was calculated during growth. Carcass, meat and fat quality parameters were measured. Immunocastrated grew faster than CM or FE after the second dose of vaccine. IM had the lowest dressing percentage but similar % of ham and carcass lean to FE and CM. The effect of the immunocastration on carcass fatness depended on the location, did not affect fat and meat quality and reduced skatole and androstenone levels. Both in green and dry-cured ham, immunocastration slightly altered FA composition. Thus, Duroc pigs vaccinated with Improvac are suitable for the production of high quality dry-cured ham.     

Sensory characterization of meat from pigs vaccinated against gonadotropin releasing factor compared to meat from surgically castrated,entire male and female pigs

Boar taint is a sensory defect mainly due to androstenone and skatole. The most common method to control boar taint is surgical castration at an early age. Vaccination against gonadotropin releasing factor (also known as immunocastration) is an alternative to surgical castration to reduce androstenone content. In this experiment, loins from 24 female (FE), 24 entire male (EM), 24 vaccinated males (IM) and 23 surgically castrated males (CM) were evaluated by eight trained panellists in 24 sessions. Loins were cooked in an oven at 180 °C for 10 min. Furthermore loins were evaluated by consumers and its androstenone and skatole content were also chemically determined. Meat from EM had higher androstenone and skatole odour and flavour than meat from FE, IM and CM and lower sweetness odour scores. High correlations were found between androstenone and skatole levels assessed by trained panelists, chemical analysis and consumers’ acceptability. Moreover meat from EM is mainly related to androstenone and skatole attributes.     

Consumers' sensory acceptability of pork from immunocastrated male pigs

Boar taint is the off-odour or off flavour of cooked pork. Currently, the most common method of controlling boar taint is surgical castration. However, immunocastration has been used in some parts of the world as an alternative to surgical castration. The aim of this study was to evaluate the sensory acceptability of meat from immunocastrated pigs (IM) compared with meat from females (FE), surgically castrated (CM) and entire males (EM). Twenty animals of each type were evaluated by 201 consumers in 20 sessions. Longissimus thoracis muscle of the different animals was cooked in an oven at 180 °C for 10 min. Consumers scored the odour and the flavour of the meat in a 9-point category scale without an intermediate level. There were no significant differences in consumer’s evaluation of meat from IM, CM, and FE. In contrast, EM meat presented a higher percentage of dissatisfied scores and was significantly (P < 0.05) less accepted than meat from CM, IM and FE. Consumers’ acceptability of EM meat was always lower, independently of its androstenone levels. However meat with low levels of androstenone was more accepted that meat with medium or high levels of this substance. It can be concluded that immunocastration produced pork that was accepted by the consumers, and was indistinguishable from pork from CM or FE.     

Consumers’ sensory acceptability of pork from immunocastrated male pigs

Boar taint is the off-odour or off flavour of cooked pork. Currently, the most common method of controlling boar taint is surgical castration. However, immunocastration has been used in some parts of the world as an alternative to surgical castration. The aim of this study was to evaluate the sensory acceptability of meat from immunocastrated pigs (IM) compared with meat from females (FE), surgically castrated (CM) and entire males (EM). Twenty animals of each type were evaluated by 201 consumers in 20 sessions. Longissimus thoracis muscle of the different animals was cooked in an oven at 180 °C for 10 min. Consumers scored the odour and the flavour of the meat in a 9-point category scale without an intermediate level. There were no significant differences in consumer’s evaluation of meat from IM, CM, and FE. In contrast, EM meat presented a higher percentage of dissatisfied scores and was significantly (P < 0.05) less accepted than meat from CM, IM and FE. Consumers’ acceptability of EM meat was always lower, independently of its androstenone levels. However meat with low levels of androstenone was more accepted that meat with medium or high levels of this substance. It can be concluded that immunocastration produced pork that was accepted by the consumers, and was indistinguishable from pork from CM or FE.     

The effects of gender and castration of females on performance and carcass and meat quality of heavy pigs destined to the dry-cured industry

The effects of gender and castration of females (IF, intact females; CF, castrated females; CM, castrated males) on performance and carcass and meat quality were studied in crossbred pigs (Landrace × Large White dams × Duroc sires) slaughtered at 119.2 (experiment 1) or 131.6 (experiment 2) kg body weight. Intact females had better feed conversion and less carcass fat than CF and CM. Trimmed shoulder yield was higher for CM than for CF with IF being intermediate. Primal cut yield and meat quality were similar for all treatments. Proportion of linoleic acid in backfat was lower in CF than in IF or CM and the differences were significant when pigs were slaughtered at 131.6 kg. The higher fat content and the fatty acid profile favor the use of castrated females and males over intact females for the production of heavy pigs destined to the dry-cured industry.     

Effects on performance and carcass and meat quality attributes following immunocastration with the gonadotropin releasing factor vaccine Bopriva or surgical castration of Bos indicus bulls raised on pasture in Brazil

Bos indicus bulls 20 months of age grazed on pasture in Minas Gerais, Brazil either received 2 doses of the GnRF vaccine Bopriva at d0 and d91 (group IC, n = 144) or were surgically castrated on d91 (group SC, n = 144). Slaughter on d280, was 27 weeks after castration. Adverse safety issues in 8% of group SC bulls following surgery contrasted with 0% in group IC bulls. At d105 testosterone levels were suppressed to similar levels in both groups. Importantly, group IC bulls had higher live weight, hot carcass weight, ADG (P < 0.005) and dressing percentage (P < 0.0001) compared to group SC animals. There were no negative effects on carcass or meat quality traits, thus immunocastration was concluded to offer a safe and effective method that provides production gains, and improves animal welfare in Bos indicus beef bulls without impacting meat and carcass quality.     

Effect of pre- and post-pubertal castration on Piemontese male cattle. II: Carcass measures and meat yield

The effect of different castration ages on carcass morphological characteristics, meat yield, commercial cuts and bones weight and measures was evaluated on Piemontese steers and bulls. Carcasses (24) obtained from early castrated (EC, 5th month of age), late castrated (LC, 13th month) and intact males (IM, control group) of similar age (about 18 months) and fattening degree, were weighed, measured and dissected following the local commercial method. Very few differences were found in carcass conformation and fatness as in carcass weight and measures. After data adjusting, few meat cuts were heavier in IM compared to EC and LC, and only one cut measure was different, whereas, almost no differences were found in bone measures and weight. IM produced carcasses with more edible meat than LC and more forequarter and 2nd quality meat than LC and EC. Significant differences were found also between total, hindquarter and perinephric fat.     

Effect of gender and castration of females and slaughter weight on performance and carcass and meat quality of Iberian pigs reared under intensive management systems

A total of 360 Iberian dam × Duroc sire pigs was used to study the influence of gender and castration of females (CM, castrated males; CF, castrated females; IF, intact females) and slaughter weight (SW; 145 and 156 kg body weight, BW) on performance and carcass and meat quality. Each treatment was replicated four times (15 pigs). Intact females ate less, tended to have better feed conversion and had less carcass fat and more primal cuts yield than CM and CF. Pigs slaughtered at 156 kg BW ate more feed and had worse feed conversion than pigs slaughtered at 145 BW. An increase in SW improved carcass yield, but tended to decrease trimmed ham yield. Intact females are an alternative to castrated females for intensive production of Iberian pigs. Also, the reduction in slaughter weight from 156 to 145 kg BW is recommended for this type of production.     

Effect of concentrate level and slaughter body weight on growth performances,carcass traits and meat quality of Barbarine lambs fed oat hay based diet

This study was conducted to evaluate concentrate level (CL) and slaughter body weight (SW) effects on growth performances, carcass traits and meat quality of Barbarine lambs. Twenty-four weaned male lambs (23.1 kg), receiving an oat-hay based diet, were allotted into two groups. The LCL group received low concentrate level (300 g) and the HCL group received high concentrate level (600 g). Lambs were slaughtered at two prefixed weights (35 and 42 kg). For each group and each weight, six lambs were slaughtered. Lambs from HCL group had higher ADG, carcass yields, carcass compactness and subcutaneous fat thickness, and lower carcass meat proportion. CL increase did not affect meat pH, meat and fat color, chemical and fatty acid composition. Late slaughtering improved carcass yields and increased carcass adiposity. However, it did not affect carcass meat proportion and shoulder tissue composition. SW had effect on meat color and fatty acid composition.     

Influence of sex and terminal sire line on performance and carcass and meat quality of Iberian pigs reared under intensive production systems

A trial was conducted to study the effects of sex (castrated males; females) and terminal sire line (DD, Danish Duroc; SD, Spanish Duroc; RIB, Retinto Iberian) on performance and carcass and meat quality of pigs slaughtered at 145 kg body weight. The female line was pure Iberian in all cases. Each treatment was replicated five times (six pigs). Females were more efficient, had less carcass and inter- and intramuscular fat and more trimmed primal cuts yield than castrated males. Duroc sired pigs grew faster and had better feed conversion and carcass quality than RIB sired pigs. Crossbreeds from SD had less carcass yield than crossbreeds from DD or RIB. We conclude that productive performance and primal cuts yield were higher for females than for castrated males. Danish Duroc sires are an alternative to Spanish Duroc and Retinto Iberian sires for production of heavy pigs destined for the dry cured industry.     

The effects of method of castration,rearing condition and diet on sensory quality of pork assessed by a trained panel

Beside surgical castration possible alternatives helping to reduce the incidence of boar taint in cooked pork are rearing conditions, immunocastration and feeding strategies for entire males known to lower the skatole levels. The goal of this study was to assess the effects of these alternatives on the sensory acceptability of pork. In experiment 1, carcasses from barrows, entire males (EM) and entire males fed raw potato starch (EM+) 7 d before slaughter were selected based on the androstenone (≤ 2 µg/g) and skatole (≤ 0.32 µg/g) levels. In experiment 2, carcasses from barrows, immunocastrates (IC), entire males either group-penned (EMG) or individually penned (EMP) were selected based on the aforementioned criteria. Boar odour and boar flavour intensities of longissimus dorsi (LD) and neck chops were evaluated by trained panellists. Boar odour and flavour scores were higher (P < 0.01) in neck than LD chops. Although skatole tissue levels in barrows and EM+ were similar (P > 0.05), boar odour and flavour scores were greater (P < 0.05) in EM+ than barrows. In experiment 2, scores for boar odour and flavour were lower (P < 0.05) in pork from barrows and IC than EMP, with intermediate values for EMG. In conclusion, we observed a discrepancy between the known boar taint compounds androstenone and skatole and sensory acceptability, which indicates that other factors influenced the perception of boar taint. Thus, surgical castration with or without anesthesia or immunocastration are still the safest methods to avoid boar taint.     

Carcass characteristics of feedlot lambs fed crude glycerin contaminated with high concentrations of crude fat

Thirty non-castrated male lambs with 20 ± 2.3 kg average body weight (BW) were randomly assigned to five treatments consisted of different dietary concentrations of crude glycerin (CG; 0, 3, 6, 9 and 12% on DM basis) to evaluate the effects on performance, carcass and meat quality traits. A quadratic effect was observed for performance (P = 0.04), final BW (P < 0.01) and hot carcass weight (P < 0.01). No effects of CG were observed (P > 0.05) on carcass pH neither on shear-force, cooking loss and ether extract content in longissimus. The inclusion of CG tended to reduce the Zn content in meat (P = 0.09). The data suggests that CG (36.2% of glycerol and 46.5% of crude fat) may be used in diets of finishing lambs with concentrations up to 3% without negative effects on performance and main carcass traits. Moreover, inclusion of CG seems to not affect quality and safety of meat for human consumption.     

The effect of the Texel muscling QTL (TM-QTL) on meat quality traits in crossbred lambs

A quantitative trait locus (QTL) has been identified on chromosome 18 in Texel sheep (TM-QTL) that increases depth and area of the longissimus dorsi muscle. The study aimed to assess the pleiotropic QTL effects on key meat quality traits (toughness and intramuscular fat content after ?7 days aging) of crossbred lambs carrying one copy of the TM-QTL. The results showed that male Texel × Mule lambs carrying the TM-QTL had significantly less intramuscular fat (1.86% versus 2.25%) and higher toughness, with increased variation, in the loin muscle, compared to non-carrier males. Similar conclusions were obtained using two different types of tenderometer equipment: one using the Volodkevitch test (average shear force of 4.17 kgF or 40.9 N for carrier males, 2.61 kgF or 25.6 N for non-carrier males) and one using the MIRINZ test (average shear force of 6.18 kgF or 60.6 N for carrier males, 5.22 kgF or 51.2 N for non-carrier males). Although most toughness measurements were within published consumer acceptability limits, a few individual TM-QTL carrier lambs had unacceptably tough meat, despite enhanced post-slaughter processing. The TM-QTL did not significantly affect loin toughness in female lambs, leg toughness in either sex, or intramuscular fat content. These results should be considered, alongside direct effects of the TM-QTL on muscling and carcass composition, in recommendations for the use of this QTL by sheep breeders.     

Fatty acid profile,carcass and meat quality traits of young Nellore bulls fed crude glycerin replacing energy sources in the concentrate

Carcass and meat quality traits of 60 Nellore young bulls fed diets without crude glycerin (CG); with CG replacing corn (CGc; 10% of dry matter — DM) in the concentrate; and with CG replacing soybean hull (CGsh; 10% of DM) in the concentrate were evaluated. Diets were evaluated at two concentrate levels (CLs). The CL did not affect cold carcass weight (CCW; P = 0.6074), cold carcass dressing (CCD; P = 0.9636), rib fat thickness (RFT; P = 0.8696) and longissimus muscle area (LMA; P = 0.7524). Animals fed diets with CGc or CGsh showed meat with greater deposition of monounsaturated fatty acid (MUFA; P = 0.0022) and CLA (18:2 cis-9, trans-11) contents (P = 0.0001) than animals fed diets without CG. The inclusion of 10% of CG in diets CGc or CGsh does not affect the carcass and meat quality traits; however, it increases the MUFA and CLA contents in beef, although these changes are very small in nutritional terms.     

The effect of seasonality of the growing–finishing period on carcass,meat and fat characteristics of heavy barrows and gilts

A trial was conducted to study the effect of gender (barrows; gilts) and seasonality of growing–finishing period (S, summer; W, winter) on the carcass and meat characteristics and fatty acid (FA) profile of subcutaneous fat of pigs slaughtered at 131 kg of body weight. No significant gender × seasonality interaction was detected and the differences between genders were scarce. The S pigs had a 13.2% thinner fat depth over the Gluteus medius muscle and a higher yield of shoulders and loins by 10.6% and 10.0%, respectively than W pigs. Meat from S pigs had 32.5% lower intramuscular fat content and higher cooking losses (9.1%) and shear force (6.4%) than meat from W pigs. Subcutaneous fat from S pigs had a 7.8% higher percentage of saturated FA and 4.9% lower monounsaturated FA than that from W pigs. It is concluded that in Spanish natural-environment facilities, the seasonality of the growing–finishing period affects the carcass, and meat and fat quality of heavy pigs.     

Carcass characteristics of Criollo Cordobés kid goats under an extensive management system: Effects of gender and liveweight at slaughter

Thirty males and thirty females suckling Criollo Cordobes kid goats of approximately 60 to 90 days old were used in this study. Kids were slaughtered at < 9.5 kg, > 9.5 < 11 kg and > 11 kg of empty body weight. The carcasses showed a medium conformation index. The meat and fat colour, and internal subcutaneous fatness were mainly scored as either pink, cream, slight and low-medium, respectively. The shoulder comprised 66–67% muscle, 24–27% bone and 4–6% fat. The slaughter weight had significant effects on the following characteristics: dressing yield, carcass measures and indices, subcutaneous fatness, meat colour, and muscle/fat ratio. The effect of gender was smaller: the female kids presented the highest fatness values for all parameters studied. Also, these animas displayed the lowest percentage of joints of extra class. The meat of female kids contained significantly less muscle and bone and a higher proportion of fat than that of male kids.     

The effects of immunological castration against GnRH with recombinant OL protein (Ovalbumin-LHRH-7) on carcass and meat quality characteristics,histological appearance of testes and pituitary gland in Kıvırcık male lambs

The aims of the study were to investigate the effects of immunization against GnRH using OL protein (Ovalbumin-LHRH-7) on feedlot performance, carcass, meat quality and some reproductive traits in K?v?rc?k ram lambs. Ram lambs in the immunization (I, n = 7) group were immunized against GnRH using OL protein and boosted 2 weeks later. Control (C, n = 7) group was not treated. The animals were kept at pasture for 6 weeks after the first immunization, subjected to a 70 day fattening program, and then slaughtered. Growth performance, various carcass and meat quality characteristics were not affected from the immunization. GnRH immunization induced GnRH antibody production, suppressed testosterone production and testicular growth (P < 0.01). Testicular structure was negatively affected from the immunization, but not pituitary. These results suggest that immunization against GnRH with OL could be an alternative castration technique in ram lambs without negatively affecting carcass and meat quality characteristics.     

Effects of genotype and dietary oil supplementation on performance,carcass traits,pork quality and fatty acid composition of backfat and intramuscular fat

A 42-day study was conducted to evaluate the effect of genotype: terminal sire line Duroc × F1 (DC×F1); terminal sire line Embrapa MS-115 × F1 (MS-115×F1); and MS-115 × Moura (MS-115×MO) and three dietary oil sources: soybean; canola; and canola + flax, on performance, carcass traits, pork quality, and fatty acid composition. Genotype affected the technological quality of pork and fatty acid profile. MS-115-sired pigs had better meat color and Duroc-sired pigs had higher intramuscular fat content, more saturated fat and better omega-6/omega-3 ratio. Moura breed influenced positively meat tenderness and intramuscular fat. Diet did not affect the technological quality of the meat. Canola or canola + flax oil diet supplementations increased monounsaturated and C18:3 and decreased C18:2 fatty acids, reducing the omega-6/omega-3 ratio. The best omega-6/omega-3 ratio was obtained through supplementation with canola + flax.     

Effect of a supplementation of Euphorbia heterophylla on nutritional meat quality of Guinea pig (Cavia porcellus L.)

The aim of the present work was to study the effect of dietary supplementation of Euphorbia heterophylla on the quality of the Guinea pig meat. Forty guinea pigs were divided into two groups fed ad libitum during 46 days a Panicum maximum diet (Panicum diet) or a mixed diet (75% Panicum maximum + 25% Euphorbia heterophylla) (Paneuphorbia diet) to compare their effects on performances and on the composition of guinea pig tissues and carcass. Daily weight gain, liver weight, carcass yield, and the lipid content of both the carcass and the perirenal fat were significantly increased by the Paneuphorbia diet. Feeding Paneuphorbia diet increased (P < 0.05) the n-3 PUFA content in perirenal fat, muscle, liver and in the carcass and decreased (P < 0.05) the n-6/n-3 ratios in all these tissues and the carcass. In conclusion, this study shows that Euphorbia heterophylla is a source of n-3 fatty acids which can improve significantly the n-3 PUFA content of Guinea pig meat and carcass.     

Effect of long term dietary supplementation with plant extract on carcass characteristics meat quality and oxidative stability in pork

The effects of dietary supplementation in pigs with plant extract (PE) from Lippia spp., titrated in verbascoside (5 mg/kg feed), from weaning to slaughter (166 days), on carcass characteristics, meat quality, collagen characteristics, oxidative stability and sensory attributes of Longissimus dorsi (LD) muscle were examined. Ten pigs per treatment were slaughter at a live weight of 109.5 ± 1.4 kg. No influence on carcass characteristics, LD meat quality parameters and collagen characteristics were observed. Dietary PE increased (P < 0.001) α-tocopherol levels in LD muscle. Raw LD of pig fed PE showed lower (P < 0.001) lipid oxidation levels than controls. A reduction (P = 0.05) of fat odor and rancid flavor intensity in cooked LD muscle stored at 4 °C for 24 h was observed in the treated group. This study shows that PE is an effective antioxidant in pork meat, enhancing oxidative status and sensory attributes, without affecting other meat quality parameters.