Carcass Backfat Thickness Research Articles

Performance, nutrient utilization and meat quality traits in Bos indicus cattle: a meta-analysis examining the effect of residual feed intake.

This meta-analysis aims to investigate the effects of residual feed intake (RFI) phenotype on performance, nutrient utilization and meat quality traits in Zebu (Bos indicus) cattle. Twenty-three peer-reviewed publications with 37 treatment means were included in the dataset. Weighted mean difference analysis compared animals categorized into low RFI (more efficient) versus medium or high RFI (less efficient) groups. Data heterogeneity via meta-regression and subgroup analysis, considering variables such as animal age, sex class, experimental duration, RFI group, dietary concentrate, and estimated metabolizable energy intake were also explored. The predominant genetic group of cattle in the dataset was Nellore (89.18%), followed by Brahman (10.81%). More efficient animals (low RFI phenotype) exhibited less dry matter intake (DMI; P < 0.010) than medium or high RFI animals (-0.95kg vs. -0.42kg/d). Cattle dietary crude protein and fiber digestibility were consistent across RFI groups (P > 0.05), while dietary ether extract digestibility tended to decrease (P = 0.050) in low RFI animals (-13.20g/kg DM). Low RFI animals tended to increased (P = 0.065) ribeye area (REA) compared to the high/medium RFI groups, while carcass backfat thickness (BFT) decreased (P = 0.042) compared to high/medium RFI groups. Moreover, there was an increase (P < 0.001) of 0.22kg in Warner-Bratzler shear force (WBSF) and a reduction (P < 0.001) in the myofibrillar fragmentation index (MFI) in low RFI animals. Meat color parameters (lightness [L*] and yellowness [b*]) and visual marbling scores were consistent (P > 0.05) across RFI groups. In conclusion, Zebu cattle classified as efficient (low RFI) exhibited reduced DMI, which improves their feed efficiency. However, BFT and meat quality parameters such as tenderness (WBSF and MFI) and redness [a*] were compromised by low RFI phenotype, highlighting the challenge of enhancing feed efficiency and meat quality traits in Zebu cattle.

Muscle Fiber, Connective Tissue and Meat Quality Characteristics of Pork from Low Birth Weight Pigs as Affected by Diet-Induced Increased Fat Absorption and Preferential Muscle Marbling.

This study investigated how birth weight differences in piglets affected carcass and muscle fiber properties as well as meat quality at slaughter. Within litters, piglets were grouped according to their birth weight as either normal (NBW; 1.62-1.73 kg) or low (LBW; 1.18-1.29 kg). At 5 weeks of age, NBW piglets were randomly transitioned to control (C) or isocaloric high fat diets derived from non-dairy (HF), while LBW piglets were randomly transitioned to high fat diets derived from non-dairy (HF) or dairy sources (HFHD). Piglets were reared in individual pens under standardized housing and feeding conditions. Live weight was recorded weekly, and pigs were slaughtered at 12 weeks of age. Hot carcass weights, dressing percentages, lean meat yield, and primal cut proportions were determined. The m. longissimus thoracis was collected from the right side of the carcass for measurement of physical and chemical properties of meat and muscle fiber characteristics. Results indicated that LBW pigs compensated for their live weight compared to NBW pigs at 6 weeks of age. The mean muscle fiber diameter of LBW-HFHD group is significantly higher than NBW-C and NBW-HF group, and the type I muscle fiber diameter is significantly higher than NBW-C group. Dairy fat inclusion in LBW pig diet reduced carcass back fat thickness. This increased the calculated lean meat yield to be comparable to that of NBW pigs fed a commercial diet. Incorporating dairy-sourced high-fat into LBW pigs' diets appears to be an effective strategy for producing carcasses equivalent to NBW pigs.

Functional SNPs in SYISL promoter significantly affect muscle fiber density and muscle traits in pigs.

Our previous studies showed that SYISL is a negative regulator of muscle growth and regeneration in mice, pigs and humans. SYISL knockout resulted in an increase in the density of muscle fibers and muscle growth. However, it is unclear whether there are natural mutations in pig SYNPO2 intron sense-overlapping lncRNA (pSYISL) that affect the expression of pSYISL and muscle growth traits. In this study, three SNPs in exons and six SNPs within the promoter of pSYISL were identified. Association analysis showed that the two SNPs in exons are significantly associated with loin muscle area (p < 0.05); the six SNPs in the promoter that show complete linkage are significantly associated with live backfat thickness and live loin muscle area in American Large White pigs. Bioinformatics and luciferase reporter assays as well as in vitro binding experiments indicated that the mutation of SNP rs702045770 (g.539G>A) leads to the loss of YY1 binding to the promoter, thus affecting the expression level of pSYISL, and we found that Jiangshan Black pigs with genotype GG have a higher expression level of pSYISL than genotype AA individuals, but the muscle fiber density was significantly lower than in genotype AA individuals. Furthermore, the association analysis showed that the carcass backfat thickness of genotype GG of SNP rs702045770 was significantly higher than that of other genotypes in (Pietrain × Duroc) × (Landrace × Yorkshire) crossbred pigs (p < 0.05). The glycolytic potential of genotype GG was significantly higher than that of other genotypes (p < 0.05). These results provide novel insight into the identification of functional SNPs in non-coding genomic regions.

Duration and sex-dependent effect of betaine supplementation on growth performance and carcass backfat of finisher pigs

Context Developing strategies to reduce carcass fatness is vital to the profitability of animal production, particularly in a market where excessive backfat causes price penalties. Studies have shown that betaine supplementation has inconsistent effects on carcass fatness, which are due in part to variability in the betaine dose, duration of supplementation and growth state. Grower pigs have a greater lean:fat deposition ratio than do finisher pigs and are more sensitive to anabolic stimuli. The betaine-spared energy may be deposited as more lean tissue when betaine is supplemented during the grower phase. We hypothesised that 0.1% betaine supplementation within the grower phase is more effective in reducing carcass backfat than is supplementing in the finisher phase. Such an effect may also interact with sex. Aims The objective was to optimise betaine supplementation duration to reduce carcass backfat thickness of finisher pigs. Methods Eighty pens of pigs (39 pigs/pen) were allocated to a 2 × 2 × 2 factorial arrangement on the basis of sex (immunocastrated male vs female pigs), betaine supplementation (0 vs 0.1%) during the grower phase (10–16 weeks of age) and the finisher phase (16 weeks of age to approximately 22 weeks of age). Growth performance, carcass weight and backfat thickness were recorded. Key results Betaine supplementation during the grower phase or finisher phase reduced backfat thickness in female pigs by 0.7 mm and 0.5 mm respectively. But the effect in reducing female backfat diminished when the supplementation extended to both grower and finisher phases. No such effect was found in immunocastrated male pigs (grower phase diet × finisher phase diet × sex, P &lt; 0.05). Betaine supplementation during the finisher phase reduced growth rate by 40 g per day, regardless of sex (finisher phase diet, P &lt; 0.05). Conclusions The effect of betaine in reducing carcass backfat was observed in female pigs only. Additionally, this occurred only when betaine was supplemented for 6 weeks in either the grower or finisher period, with supplementation for the 12-week period negating the effect. Implications The effectiveness of betaine supplementation in reducing carcass backfat is sex and duration dependent.

Genome-wide association study identifying genetic variants associated with carcass backfat thickness, lean percentage and fat percentage in a four-way crossbred pig population using SLAF-seq technology

BackgroundCarcass backfat thickness (BFT), carcass lean percentage (CLP) and carcass fat percentage (CFP) are important to the commercial pig industry. Nevertheless, the genetic architecture of BFT, CLP and CFP is still elusive. Here, we performed a genome-wide association study (GWAS) based on specific-locus amplified fragment sequencing (SLAF-seq) to analyze seven fatness-related traits, including five BFTs, CLP, and CFP on 223 four-way crossbred pigs.ResultsA total of 227, 921 highly consistent single nucleotide polymorphisms (SNPs) evenly distributed throughout the genome were used to perform GWAS. Using the mixed linear model (MLM), a total of 20 SNP loci significantly related to these traits were identified on ten Sus scrofa chromosomes (SSC), of which 10 SNPs were located in previously reported quantitative trait loci (QTL) regions. On SSC7, two SNPs (SSC7:29,503,670 and rs1112937671) for average backfat thickness (ABFT) exceeded 1% and 10% Bonferroni genome-wide significance levels, respectively. These two SNP loci were located within an intron region of the COL21A1 gene, which was a protein-coding gene that played an important role in the porcine backfat deposition by affecting extracellular matrix (ECM) remodeling. In addition, based on the other three significant SNPs on SSC7, five candidate genes, ZNF184, ZNF391, HMGA1, GRM4 and NUDT3 were proposed to influence BFT. On SSC9, two SNPs for backfat thickness at 6–7 ribs (67RBFT) and one SNP for CLP were in the same locus region (19 kb interval). These three SNPs were located in the PGM2L1 gene, which encoded a protein that played an indispensable role in glycogen metabolism, glycolysis and gluconeogenesis as a key enzyme. Finally, one significant SNP on SSC14 for CLP was located within the PLBD2 gene, which participated in the lipid catabolic process.ConclusionsA total of two regions on SSC7 and SSC9 and eight potential candidate genes were found for fatness-related traits in pigs. The results of this GWAS based on SLAF-seq will greatly advance our understanding of the genetic architecture of BFT, CLP, and CFP traits. These identified SNP loci and candidate genes might serve as a biological basis for improving the important fatness-related traits of pigs.

Relationship between energy intake and growth performance and body composition in pigs selected for low backfat thickness.

Genetic selection of pigs over recent decades has sought to reduce carcass fat content to meet consumer demands for lean meat in many countries (e.g., Australia). Due to the impacts of genetic changes, it is unknown whether the carcass fat measures are still responsive to energy intake. Thus, the present experiment aimed to quantify the relationship between tissue composition and dietary energy intake in finisher pigs selected for low carcass backfat. Intact male and female pigs (n = 56 for each sex; Primegro Genetics, Corowa, NSW, Australia) were fed seven different amounts of an amino acid adequate wheat-based diet containing 14.3 MJ digestible energy (DE)/kg to provide the following daily DE intakes- 25.8, 29.0, 32.6, 35.3, 38.5, 41.5, and 44.2 (ad libitum) MJ DE/d for males, and 25.8, 28.9, 32.0, 35.6, 38.3, 40.9, and 44.5 (ad libitum) MJ DE/d for females between 60 and 108 kg live weight. Body composition of anesthetized pigs was measured using the dual energy X-ray absorptiometry (DXA) method when individual pigs reached 108 kg, and protein, fat, and ash deposition rates were calculated. Pigs were slaughtered on the second day post-DXA scan for carcass backfat measurement. The results showed that the carcass backfat thickness (standardized at 83.7 kg carcass) increased by 0.125 mm for every MJ increase in daily DE intake in male pigs (P = 0.004; R2 = 0.130), but carcass backfat of female pigs (standardized at 85.1 kg carcass) was not responsive to daily DE intake. Whole-body fat composition and fat deposition rate increased linearly (both P < 0.01) in male pigs but quadratically (both P < 0.01) in female pigs in response to DE intake. Every MJ increase of daily DE intake increased the rate of daily protein deposition by 3.8 g in intact male pigs (P < 0.001; R2 = 0.781) and by 2.5 g in female pigs (P < 0.001; R2 = 0.643). In conclusion, the selection for low backfat thickness over the last two decades has altered the response of fat deposition and backfat thickness to energy intake, particularly in female pigs. Despite this change, the linear relationship between DE intake and protein deposition rate was maintained in these modern genetics.

153 Differences in Health and Carcass Characteristics of Yearling Steers That Received Free-choice Garlic-infused Mineral Supplements

Abstract Garlic products have been reported to have antimicrobial effects and may trigger anemia in horses, but their direct impact on feedlot cattle has not been detailed. With increased free-choice feeding of garlic-infused mineral supplements to beef cattle, it is important to evaluate this strategy’s impact on the animals’ health and the potential impact on carcass qualities. This 2-yr study recruited 208 crossbred feedlot steers in a supplementation trial using a completely randomized design. Each year, 104 steers were assigned to 1 of 4 groups that received either non-garlic mineral supplement (MS), MS + 0.3% garlic-oil-based premix (GOil), MS + 2.5% garlic powder (LGP), MS + 5% garlic powder (HGP). Feed and supplements were provided on an ad-lib basis and were measured for each steer with automatic feeding units. The study evaluated health indicators such as blood parameters and internal parasites. At harvest, carcass characteristics (including the incidence of liver abscesses) were assessed for all steers. The groups consumed between 156 and 208 g/d of the supplement over the two years, with the MS group having a lower overall supplement intake than other groups. The average daily consumption of garlic products in GOil, LGP, and HGP were approximately 0.6g/d, 5.2g/d, and 10.1g/d, respectively. There was no difference in total fecal egg counts (P = 0.45) among the groups. There was no association between the treatment groups and incidences of liver abscess scores (P = 0.10) nor carcass grade outcomes (P = 0.84). Further, there were no differences in hot carcass weight (P = 0.90), rib eye area (P = 0.34) and carcass backfat thickness (P = 0.99). All blood parameters evaluated were within normal ranges for all groups. The results suggest that infusing commercial garlic products into mineral supplements is not associated with undesirable effects on cattle health or carcass characteristics.

PSXIII-11 Evaluating different doses of rumen-protected or nonprotected tributyrin on performance of feedlot lambs fed a moderate or low-forage diet

Abstract The objective of this study was to evaluate performance of lambs when supplemented with different doses and forms of tributyrin in moderate (MF) and low forage (LF) diets. Eighty-four ram lambs were blocked by initial BW (27.9 ± 2.3 kg) assigned into 1 of 2 groups that were fed a MF (40% forage) or LF (10% forage) diet (%DM). Lambs in each block were also assigned to 1 of 6 treatments (n = 7) including a control (no supplementation) or diets that contained 0.1, 0.2, or 0.3% (DM basis) rumen protected (RPT) or 0.1 or 0.3% of tributyrin that was not protected (NPT). Lambs were housed indoor in individual pens and fed once daily for 97 d. At harvest, hot carcass weight (HCW) and back-fat thickness was measured for each lamb. Within diet type (MF and LF), data were analyzed to determine the linear and quadratic response for increasing RPT, the effect of using tributyrin (con vs. RPT and NPT), and the effect of rumen protection (RPT vs. NPT). Treatments fed MF diets did not differ with each other (P ≥ 0.06) for final BW (53.5 kg), ADG (255 g/d), DMI (1.42 kg/d), gain:feed ratio (0.187 kg/kg), backfat thickness (14.1mm), hot carcass weight (24.0 kg), and dressing percentage (45.0%). Also, no differences (P ≥ 0.08) were detected for final BW (56.0 kg) and ADG (0.30 kg/d), DMI (1.56 kg/d), gain:feed ratio (0.190 kg/kg), back-fat thickness (16.8 mm), and HCW (25.5 kg) between treatments fed LF diets. However, lambs fed LF diet with RPT had greater (P = 0.04) dressing percentage than lambs fed NPT (45.9 vs. 44.5%, respectively). We conclude there is no benefit from inclusion of tributyrin in MF diets for lambs whether provided in protected or unprotected form. However, feeding RPT in LF diets for lambs may enhance dressing percentage.

High-level dietary crude protein decreased backfat thickness and increased carcass yield score in finishing Hanwoo beef cattle (Bos taurus coreanae).

Recently, a high level of dietary crude protein (CP) has become of interest as a possible practice to improve the carcass quality of beef cattle, and its level has been increasing in the field. However, there is little scientific evidence that supports this. This study was conducted to test whether a high dietary CP level would improve growth performance, body metabolism, and carcass traits in Hanwoo beef cattle. A total of 32 Hanwoo finishing beef cattle (18 multiparous cows, six heifers, and eight steers) participated in a 12-weeks feeding trial. Two kinds of total mixed rations were prepared to contain two different CP; 156 g/kg for the control (CON) and 173 g/kg of CP for the treatment (HCP), while maintaining a similar level of metabolizable energy. The experiment was ended when more than half of the steers reached the target body weight (730 kg). Blood was collected at the end of the experiment. After harvesting, the carcass trait was evaluated at the slaughterhouse according to Korean standards. The carcass yield score and grade were also calculated based on revised criteria. Overall, dry matter intake, average daily gain, blood metabolites concentration, and the carcass traits, except for backfat thickness and the yield score, did not differ between the treatments. The HCP had lower backfat thickness than those of CON. There was no difference in the carcass yield grade, but the yield score was higher in the HCP treatment. According to the newly revised carcass grading criteria, both yield score and grade were higher in HCP than in CON. Increasing CP supply decreased the carcass’s backfat thickness without altering growth performance and body metabolism, resulting in improved yield score and grade. Therefore, feeding a high CP diet may be beneficial in the farm income, although it may also increase feed cost and nitrogen excretion to the environment.

Effects of adding high-dosing Aspergillus oryzae phytase to corn-wheat-soybean meal-based basal diet on growth performance, nutrient digestibility, faecal gas emission, carcass traits and meat quality in growing-finishing pigs.

This study tests the effects of supplementation of high-dosing Aspergillus oryzae phytase into the corn-wheat-soybean meal (SBM)-based basal diet on growth performance, nutrient digestibility, faecal gas emission, carcass traits and meat quality in growing-finishing pigs (29.73-110.86kg live weight; 70-day-old to 166-day-old). A total of 56 crossbred pigs [(Landrace×Yorkshire)×Duroc] were divided into two dietary groups for a 96-day experiment (growing period, days 0-42; finishing period, days 43-96) with a completely randomized block design. There were seven replicate pens in each dietary group, and each pen has four pigs (two barrows and two gilts). The dietary treatments consisted of a corn-wheat-SBM-based nutrient sufficient basal diet or the basal diet supplemented with 1500FTU/kg A.oryzae phytase. One phytase unit (FTU) was defined as the amount of enzyme that catalyses the release of one micromole phosphate from phytate/min at 37°C and pH 5.5. Higher average daily gain and lower feed conversion ratio were observed in growing-finishing pigs consuming a high-dosing A.oryzae phytase supplementing diet during days 0-42 and 0-96. Supplementing high-dosing A.oryzae phytase to the diet of growing-finishing pigs increased apparent total tract digestibility of phosphorus on days 42 and 96. Moreover, growing-finishing pigs fed the diet supplemented with high-dosing A.oryzae phytase had higher carcass back-fat thickness than those fed the control diet. However, the faecal gas emission and meat quality were not affected by high-dosing A.oryzae phytase supplementation. In conclusion, dietary supplementation of high-dosing A.oryzae phytase (1500FTU/kg) had beneficial effects on the growth performance, apparent phosphorus digestibility and carcass back-fat thickness in growing-finishing pigs.

PENGARUH PENAMBAHAN TEPUNG KUNYIT DAN BETAIN PADA RANSUM TERHADAP BERAT KARKAS, TEBAL LEMAK PUNGGUNG DAN LOIN EYE AREA BABI FINISHER (Effect of Dietary Turmeric Flour and Betain Addition on Carcass Weight, Backfat Thickness and Loin Eye Area of Finisher Pig)

Antibiotic Growth Promoter (AGP) synthetic as a feed additive can stimulate growth, prevent some health problems, and improve feed efficiency. However, its journey has raised concerns due to adverse effects such as residues and microbial resistance. The use of turmeric flour and betaine as feed additives is expected to substitute the use of AGP Synthetic in improving the performance of pig carcasses and the safety of consumption. This study was aimed to examine the effect of the addition of turmeric flour and different doses of betaine in the ration on the performance of finisher period pigs. The study was conducted experimentally using a completely randomized design with four treatments and five replications. The objects of the study were 20 male and female finisher Landrace pigs with a finisher period with initial body weights of 55-66 kg/head. The study rations used were R0: basal ration, R1: R0 + 0.4% turmeric flour + 0.1% betaine, R2: R0 + 0.4% turmeric flour + 0.15% betaine and R3: R0 + 0.4% turmeric flour + 0.2% betaine. The parameters measured were carcass weight, backfat thickness, and loin eye area. The addition of turmeric flour treatment did not have any significant effects on carcass weight and thickness of the back fat of the pig. The addition of 0.4% turmeric flour and 0.15% betaine in the ration was the best treatment and resulted in a different effect on the loin eye area compared to that of R0, while treatment R1 and R3 had a similar effect on it. The result of the addition of 0.4% turmeric flour and 0.15% betaine resulted in the loin eye area of the finisher pig of 53.4 cm2

Effect of Total Digestible Nutrients Level of Concentrates on Growth Performance, Carcass Characteristics, and Meat Composition of Korean Hanwoo Steers

This study was conducted to investigate the effect of the total digestible nutrients (TDN) level of commercial concentrates on growth performance, carcass characteristics, and meat composition of late fattening Hanwoo steers. A total of 28 steers were randomly assigned to one of four dietary groups; T1 (73.30% TDN), T2 (74.50% TDN), T3 (76.40% TDN), and T4 (77.10% TDN). Average daily gain (ADG) was slightly but not significantly higher in the T2 than in the other treatments. Dry matter intake (DMI) and feed conversion ratio (FCR) were higher in the T2 than in the other treatments; however, the differences were not statistically significant. Carcass back fat thickness was thicker in the T4 and marbling score was higher in the T2 than in the other treatments; however, the differences were not statistically significant. The TDN level of concentrates had no effect on the physicochemical characteristics and fatty acid composition of the longissimus muscle. The finding of this study indicate that less than 74% or greater than 75% TDN in the commercial concentrate did not contribute to improve ADG, FCR, marbling score; therefore, in the present study, the recommendable TDN level in the commercial concentrate for late fattening period was 74% to 75% in terms of growth performance and marbling score of Hanwoo steer.

Effects of the plane of nutrition during the latter grower and entire finisher phases on grow-finish pig performance in summer.

The present study was undertaken to investigate the effects of the plane of nutrition (PN) for growing-finishing pigs on growth performance and meat quality in summer. One hundred and two barrows and 102 gilts weighing approximately 44 kg were placed on a high-, medium-, or low-plane grower diet (HPG, MPG, or LPG) with ME and lysine concentrations ranging from 3.33 to 3.40 Mcal/kg and 0.93% to 1.15%, respectively, for 29 days in 6 replicates (pens) in total. Pigs from each grower pen were divided into two finisher pens and provided with a high-plane finisher diet (HPF) containing 3.40 Mcal ME and 9.5 g lysine/kg and a low-plane finisher diet (LPF; 3.25 Mcal ME and 8 g lysine/kg), respectively, up to approximately 110 kg, and slaughtered. Growth performance of the pigs, including average daily gain (ADG), average daily feed intake (ADFI), and gain:feed ratio, was not influenced by the grower-phase PN during any of the grower phase, a 31-d finisher phase I, and ensuing phase II. However, both the ADG and gain:feed ratio were greater (p < 0.05) for the HPF group than for the LPF group during the finisher phase I (748 vs. 653 g with SEM = 13 g and 0.333 vs. 0.299 with SEM = 0.008, respectively). The ADG, but not gain:feed ratio, was greater for the HPF group vs. LPF during the finisher phase II (673 vs. 623 g with SEM = 15 g for ADG and 0.322 vs. 0.323 with SEM = 0.005 for the gain:feed ratio). The carcass backfat thickness (BFT) was greater for the LPF group vs. HPF within the pigs which had been placed on LPG during the grower phase, but not within the pigs from the HPG or MPG group. Physicochemical characteristics of the longissimus dorsi muscle (LM) and sensory quality attributes of fresh and cooked LM were not influenced by either the grower-phase or finisher-phase PN. In conclusion, high PN is necessary for finishing pigs during the hot season to minimize the reduced rate of weight gain and also to prevent the increase of BFT that could result from low PN.

Use of regularized quantile regression to predict the genetic merit of pigs for asymmetric carcass traits

Abstract: The objective of this work was to evaluate the use of regularized quantile regression (RQR) to predict the genetic merit of pigs for asymmetric carcass traits, compared with the Bayesian lasso (Blasso) method. The genetic data of the traits carcass yield, bacon thickness, and backfat thickness from a F2 population composed of 345 individuals, generated by crossing animals from the Piau breed with those of a commercial breed, were used. RQR was evaluated considering different quantiles (τ = 0.05 to 0.95). The RQR model used to estimate the genetic merit showed accuracies higher than or equal to those obtained by Blasso, for all studies traits. There was an increase of 6.7 and 20.0% in accuracy when the quantiles 0.15 and 0.45 were considered in the evaluation of carcass yield and bacon thickness, respectively. The obtained results are indicative that the regularized quantile regression presents higher accuracy than the Bayesian lasso method for the prediction of the genetic merit of pigs for asymmetric carcass variables.

Supplementation of guanidinoacetic acid to pig diets: effects on performance, carcass characteristics, and meat quality.

Two studies were conducted to evaluate the effects of dietary supplementation of guanidinoacetic acid (GAA) on growth performance, carcass characteristics, and meat quality in pigs from wean to finish (Exp 1) and finishing pigs fed GAA at different time periods before slaughter (Exp 2). In Exp 1, a total of 360 weaned pigs (Duroc × [Landrace × Yorkshire]) with an average initial BW of 7.17 ± 0.03 kg were randomly distributed into 3 dietary treatments consisting of 10 replicates per treatment and 12 pigs (6 barrows and 6 gilts) per replicate. Dietary treatments were a control (CON; basal diet), a basal diet + 0.08% GAA (0.08% GAA); and a basal diet + 0.12% GAA (0.12% GAA). The duration of the experiment was 150 d. At the end of the experiment, 20 pigs (10 barrows and 10 gilts) from each treatment were slaughtered for measuring carcass characteristics and meat quality. In Exp 2, 1,440 finishing pigs [(Duroc × (Landrace × Yorkshire)), 56.15 ± 0.10 kg BW)] were randomly allocated to 4 treatments with 18 replicates (20 pigs per replicate). Dietary treatments were a control diet (CON; basal), a basal diet + 0.12% GAA fed 60 d before slaughter (T1), a basal diet + 0.12% GAA fed 40 d before slaughter (T2), and a basal diet + 0.12% GAA fed 25 d before slaughter (T3). Body weight was measured at the start (120 d of age) and at the end (180 d of age) of the experiment. At the end of the study, 144 pigs (72 barrows and 72 gilts) from 4 dietary treatments (36 pigs per treatment) were slaughtered for the determination of carcass and meat quality parameters. In Exp 1, 0.12 % GAA increased (P < 0.05) ADG and G:F during starter, grower, finisher, and the overall growth period (30 to 180 d of age). Pigs fed 0.12 % GAA had improved (P < 0.05) lean meat yield in comparison with CON. There was no interaction effect among GAA supplementation and sex of the pigs. Meat quality was not affected by GAA supplementation in pigs. In Exp 2, the final BW, ADG, and lean yield of the pigs fed T1 were higher (P < 0.05) than CON and those fed T3. The carcass back-fat thickness of T1 was lower (P < 0.05) than CON. In conclusion, 0.12% GAA improved the growth performance and lean meat yield in pigs from wean to finish. Finishing pigs fed diets supplemented with 0.12% GAA 60 d before slaughter improved ADG, feed efficiency, and lean meat yield and reduced back-fat thickness compared with those fed GAA unsupplemented diets.

Blood parameters, carcass and meat quality of slaughter pigs with and without liver milk spots

The aim of this study was to determine the influence of liver milk spots on hematological, carcass and meat quality parameters in slaughter pigs. A total of 120 pigs with a live weight of approximately 115 kg and six months old were examined. Any signs of liver milk spots were recorded as present or absent according to Welfare Quality? protocol (2009). A complete blood picture was investigated. The following carcass quality parameters were measured: live, hot and cold carcass weights, dressing percentage, backfat thickness and meatiness. pH and temperature measurements were performed 45 minutes postmortem. Pork quality classes (PSE - pale, soft and exudative, normal, DFD - dark, firm and dry meat) were determined according to Adzitey and Nurul (2011) using pH45 value. Pigs with liver milk spots had significantly higher middle-sized cell count (monocytes, eosinophils, and basophils) and neutrophils count, but significantly lower red blood cell count, hemoglobin concentration, hematocrit and MCV than unaffected pigs. The same group of pigs had significantly lower live weight, hot carcass weight, cold carcass weight, dressing percentage and meatiness compared to the pigs free of milk spot lesions. Pigs showing liver milk spots had significantly higher pH45 value and incidence of DFD meat than pigs without pathological lesions in the livers. In conclusion, assessment of liver milk spots at slaughter line has potential to serve not only as an indirect measure of pig health and welfare, but also for the carcass and pork quality.

Functional and association studies of the cholesteryl ester transfer protein (CETP) gene in a Wannan Black pig model.

Some polymorphisms of the human CETP gene are causally and significantly associated with serum lipids levels; however, the information regarding this gene in pigs is sparse. To evaluate the effects of CETP on blood lipid traits and fat deposition in pig, porcine CETP tissue expression patterns were observed by quantitative real-time polymerase chain reaction (qPCR) first. High expression was detected in liver, spleen, gluteus medius (GM) muscle and backfat. A de novo polymorphism (AF333037:g.795C>T) in the intron 1 region of porcine CETP was identified. This polymorphism was further genotyped by direct sequencing of the PCR products of 390 Wannan Black pigs, a Chinese native breed population. Association analyses at 45 and 300days of age revealed highly significant associations between CETP genotypes and serum lipid traits. Furthermore, this polymorphism was proved to be associated with differences in liver CETP mRNA levels: pigs at 300days of age with the TT genotype had higher levels than did those with other genotypes (P=0.021). Additionally, analysis at 300days of age showed that GM CETP mRNA expression correlated positively with serum lipids levels as well as with carcass backfat thickness and intramuscular fat content in GM. These results indicate that CETP is involved in serum, adipose and muscle lipid metabolism in pigs. The mechanisms underlying such relationships and their functional implications are worthy of further research.

Evaluation of optimum slaughter age based on carcass traits of crossbred pigs

The experiment was carried out at Pig Breeding Unit of Livestock Research Station, Kattupakkam to evaluate the optimum slaughter age based on carcass traits of crossbred pigs. A random sample of 18 crossbred growers male pig were selected at weaning, castrated and were divided into three groups. The experimental pigs were slaughtered at 7th, 8th and 9th month of age to study important carcass traits. The final body weights at 7th, 8th and 9th month of age were 37.67 ± 2.40 kg, 49.08 ± 1.95 kg and 56.50 ± 4.70 kg respectively. Statistical analysis was carried out for carcass traits. With respect to loin eye area, significant (P 0.05) differences existed between the 7th and 8th months and 7th and 9th months of slaughter age, while no difference was found between the 8th and 9th month of age. In case of carcass length and back fat thickness, significant (P 0.05) differences existed between the pigs slaughtered at 7th and 9th month of age. From this analysis, to achieve a maximum dressing percentage, carcass length and loin eye area, the 9th month of age is the ideal age for slaughter in 50 per cent crossbred pigs.

Szacowanie wartosci handlowej wybranych elementow tuszy wieprzowej na podstawie grubosci sloniny

The aim of the present study was to determine the effect of pork carcass backfat thickness on the dissection efficiency of four primal cuts (ham, loin, shoulder, belly), including correlation coefficients. The research material consisted of 80 pork carcasses. Backfat thickness (mm) was measured on cold half-carcasses using a vernier caliper at 6 points: at the first cervical vertebra (atlas), over shoulder at the thickest point, on the back, at the beginning, center, end of the gluteus medius muscle (CI, CII, CIII). On the basis of the average backfat thickness, measurements from 6 points were separated into two experimental groups: I (<25 mm); II (≥25 mm). Detailed dissection of the elements was performed to define mass (g): total, intermuscular fat, bones and lean meat. The significant effect of fat thickness on intermuscular fat content regardless of the cut was noted. Correlations between the average backfat thickness of 6 points and the total weight of the four main elements were calculated. In addition, the correlation coefficients were compared between the dissection elements and the average backfat thickness of 6 and 5 points. Higher backfat thickness determined the increase in the total mass of loin, shoulder and belly. A statistically proven correlation was shown between the average backfat thickness and the total mass of the analysed elements (r=0.293). When comparing the correlation coefficients of a different number of measurements a specific tendency was observed. Positive correlation coefficients were slightly higher for an average of 5 points of backfat thickness and negative correlation coefficients were slightly higher for an average of 6 points. Statistical differences between groups were recorded at the same level for the same parameters (P≤0.001 and 0.01<P≤0.05). The average backfat thickness of 6 points can be used as an indicator of the amount and quality of pork carcass primal cuts, with no adverse effects compared to standard 5 points.

Feeding Brassica juncea or Brassica napus canola meal at increasing dietary inclusions to growing-finishing gilts and barrows

Novel Brassica (B.) juncea has a thinner seed coat and therefore lower fibre content than conventional B. napus canola meal (CM) and could potentially be fed at greater dietary inclusions to pigs. In a 2×2×3 factorial arrangement, 528 barrows and 528 gilts [33.6kg body weight] housed in 48 pens (22 barrows or gilts) were fed either B. juncea or B. napus CM at 100, 200 or 300g/kg of diet with up to 200g/kg wheat DDGS to slaughter weight (120kg). Compared with B. napus, B. juncea CM had 32g/kg greater CP, 12g/kg lower crude fat, 86g/kg lower ADF, and 91g/kg lower NDF content. However, aliphatic glucosinolate content was 2.7 times greater in B. juncea (11.76μmol/g) than B. napus CM (4.34μmol/g). For the entire trial (d 0–72), daily weight gain (ADG) was not affected by canola species, but feed disappearance (ADFI) was 45g/d lower (P=0.06) and feed efficiency 7g/g greater (P<0.05) for pigs fed B. juncea than B. napus CM. Carcass traits were not affected by canola species except dressing, which was 1% lower (P<0.05) for pigs fed B. juncea than B. napus CM. For the entire trial, increasing CM inclusion from 100 to 300g/kg of diet decreased ADFI (P<0.001) by 184g/d, decreased ADG by 32g/d (P<0.05), but increased feed efficiency (P<0.001) by 14g/g. Dietary CM inclusion level did not affect farm ship live weight to slaughter, carcass backfat thickness, lean yield, or index. Nonetheless, carcass weight was 0.9kg lower (P<0.05), dressing was 1% lower (P<0.001), loin depth was 1.3mm lower (P<0.01), and days to slaughter was 2.3 days greater for pigs fed 300 compared with those fed 100g CM/kg diet. In conclusion, growing-finishing pigs can be fed diets including B. juncea CM the same as conventional B. napus CM without decreasing growth performance or carcass traits. Feeding growing-finishing pigs a diet with 300 vs. 200 or 100g/kg CM with up to 200g/kg of wheat DDGS resulted in decreased weight gain and a minor decrease in carcass weight, dressing and loin depth, but increased feed efficiency.