A note on porcine skeletal muscle parameters and their possible use in early progeny testing

1975 ◽  
Vol 21 (1) ◽  
pp. 93-96 ◽  
Author(s):  
N. C. Stickland ◽  
G. Goldspink
Keyword(s):  
Skeletal Muscle ◽  
Progeny Testing ◽  
Large White ◽  
Muscle Area ◽  
Eye Muscle ◽  
Fibre Density ◽  
Meat Content ◽  
Fibre Number ◽  
Highly Correlated ◽  
Total Muscle

SUMMARYAn ‘indicator muscle’ (m. flexor digiti V brevis) was removed in its entirety from several Large White and Landrace pigs of varying fat depth (measured over the eye-muscle area). The total muscle fibre number was measured in transverse sections for each muscle. Significant inverse relationships were found between this fibre number and fat depth measurements. These and other results suggest that fibre number is related to lean meat content. Fibre number was also shown to be highly correlated with fibre density and as thinner fibres (i.e. higher fibre density) are associated with more tender meat, fibre number may be associated with quality as well as quantity of meat.

Sources of variation in myofibre number within and between litters of pigs

1991 ◽  
Vol 52 (3) ◽  
pp. 527-533 ◽  
Author(s):  
C. M. Dwyer ◽  
N. C. Stickland
Keyword(s):  
Muscle Fibre ◽  
Significant Contribution ◽  
Large White ◽  
Significant Difference ◽  
Fresh Frozen ◽  
Sources Of Variation ◽  
Fibre Number ◽  
Acid Stable ◽  
Total Muscle ◽  
Secondary Fibre

ABSTRACTA study of the determinants of inter- and intra-litter variation in muscle fibre number was carried out on five litters of Large White piglets. Fresh frozen, whole mid-belly sections of m. semitendinosus were stained to demonstrate acid-stable myosin adenosine triphosphatase activity. From these sections it was possible to identify which fibres had developed as primary and which as secondary fibres. Estimations of total muscle fibre number, total primary fibre number and ratio of secondary fibres to primary fibres were made for each animal. Results demonstrated that primary fibre number varied between litters (P<0·01) and was responsible for the variation in total muscle fibre number (P < 005) between litters since there was no significant variation in secondary: primary ratio. Within-litter differences in total fibre number could be attributed to both the secondary: primary ratio and primary fibre number, in almost equal contributions. However, when only the largest and smallest extremes of the litters were compared, variation in fibre number was due to the significant difference in the secondary: primary ratio (P<0·01). Taken as a whole, the results appear to show that primary fibre number is responsible for all the variation in muscle fibre number between litters, and also makes a significant contribution, with secondary: primary fibre ratio, to the variation present within a litter. The factors responsible for variations in primary and secondary fibre numbers are discussed.

The effect of different dietary protein levels in the rearing phase (from 60 kg) on body composition and reproductive performance of gilts

1996 ◽  
Vol 1996 ◽  
pp. 143-143
Author(s):  
M C Cia ◽  
S A Edwards ◽  
V L Glasgow ◽  
M Shanks ◽  
H Fraser
Keyword(s):  
Body Composition ◽  
Reproductive Performance ◽  
Large White ◽  
Muscle Area ◽  
Eye Muscle ◽  
Protein Levels ◽  
Fat Reserves ◽  
Low Protein ◽  
Protein Diets ◽  
Real Time Ultrasonography

Low protein diets have been proposed as a way to enhance fat reserves and reduce liveweight gain in breeding animals of very lean genotypes. The objective of this study was to examine the effect of different protein levels on daily gain, body composition and reproductive performance of gilts.At 118 (sem=0.28) days old, 54 genetically lean gilts ((Landrace x Large White) x Large White) were allocated, considering firstly age and secondly weight, between three treatments with different dietary lysine:energy (g/MJ DE) ratios: High (0.9), Medium (0.6) and Low (0.3), fed twice daily at 2.9 x maintenance energy. Animals were weighed weekly and backfat thickness (P2) and muscle depth values were also taken. Eye muscle area measurements were taken by real time ultrasonography (Aloka 500) at the end of the experiment At 160 days of age, puberty was induced by administration of exogenous gonadotropin (PG600).

Evaluation of overseas pig breeds using imported semen. 2. Prediction of carcass lean content

1984 ◽  
Vol 103 (3) ◽  
pp. 571-575 ◽  
Author(s):  
R. A. Sutherland
Keyword(s):  
Prediction Equation ◽  
Large White ◽  
Muscle Area ◽  
Eye Muscle ◽  
Unbiased Estimates ◽  
Breed Comparison ◽  
Feeding Regimen ◽  
Ad Libitum ◽  
Regression Slopes ◽  
Imported Semen

SummaryAn analysis of data from the complete dissection of one side from 285 animals from a breed comparison experiment was conducted to determine whether there were important biases in the prediction of percentage lean in the side based on dissection of the rumpback joint and, if so, whether the dissection of any of five other sample joints would have been better.For estimating lean content of the side, it was found that the lean content of any sample joint except the hand was a more precise predictor than standard carcass measurements alone, while including the latter in a prediction equation based on a single sample joint dissection improved precision further. For prediction based on lean in the sample joint alone, any one of the ribback, ham and rumpback was best. If other carcass measurements were included (in particular, C fat depth, eye-muscle area and trimming percentage were found to be useful), there was little to choose between the joints. For all joints there were differences between sire breeds (Large White, Canadian Yorkshire, U.S. Duroc, U.S. Yorkshire, Danish Landrace or Norwegian Landrace), sexes (hog or gilt) and feeding regimens (ad libitum or scale) in lean content of the side at constant lean content of the sample joint, but the regression slopes differed only when the rumpback or streak was used as a predictor, and then only between ad libitum and scale-fed pigs. It will therefore be important in any future such experiment fully to dissect a sample of each class (breed, feeding regimen and sex) to provide unbiased estimates of the differences in lean content. A sample of 30 from each class should allow the differences to be estimated adequately.

scholarly journals Comparison of two muscle fibre staining techniques and their relation to pork quality traits

2020 ◽  
Vol 65 (No. 6) ◽  
pp. 193-204
Author(s):  
Nicole Lebedová ◽  
Tersia Needham ◽  
Jaroslav Čítek ◽  
Monika Okrouhlá ◽  
Kateřina Zadinová ◽  
...  
Keyword(s):  
Moisture Content ◽  
Muscle Fibre ◽  
Fibre Types ◽  
Quality Traits ◽  
Large White ◽  
Muscle Area ◽  
Cross Sectional ◽  
Eye Muscle ◽  
Staining Techniques ◽  
Atpase Staining

This study compared two histochemical staining methods of muscle fibres and evaluated their relationship with the meat quality traits of two high-value porcine muscles. Immunohistochemical (IHC) and adenosine triphosphatase (ATPase) staining was used to assess the cross-sectional area and proportion of fibre-types I, IIa, IIx and IIb in the samples of longissimus lumborum (LL) and psoas major (PM) muscles collected one-hour post-mortem from 25 crossbred pigs [Large White<sub>Sire</sub> × (Landrace × Large White<sub>Dam</sub>)] at an average age of 152 days. Muscles differed in all fibre parameters, except the proportion and relative area of type IIx fibres. The LL muscle exhibited greater fibre cross-sectional areas of all fibre types, higher proportions of type IIb/IIB, and lower proportions of I and IIa fibres than the PM muscle in both staining techniques. These two muscles also differed marginally in moisture, crude protein and intramuscular fat content. The PM muscle showed a low correlation between fibre types and chemical composition, but the LL muscle showed moderate correlations between fibre CSA and area composition for moisture and ash content. After IHC staining, an increase in LL eye muscle area and drip loss were correlated with lower proportions of type I fibres, while a greater proportion of type IIx fibres resulted in increased LL eye muscle area and moisture content. Furthermore, a higher CSA of all fibre types in the LL decreased redness (a*) and moisture content of the muscle. Results showed that IHC is more appropriate than ATPase staining for the assessment of relationships between muscle fibre parameters and meat quality traits in pigs.

The effect of different dietary protein levels in the rearing phase (from 60 kg) on body composition and reproductive performance of gilts

1996 ◽  
Vol 1996 ◽  
pp. 143-143
Author(s):  
M C Cia ◽  
S A Edwards ◽  
V L Glasgow ◽  
M Shanks ◽  
H Fraser
Keyword(s):  
Body Composition ◽  
Reproductive Performance ◽  
Large White ◽  
Muscle Area ◽  
Eye Muscle ◽  
Protein Levels ◽  
Fat Reserves ◽  
Low Protein ◽  
Protein Diets ◽  
Real Time Ultrasonography

Low protein diets have been proposed as a way to enhance fat reserves and reduce liveweight gain in breeding animals of very lean genotypes. The objective of this study was to examine the effect of different protein levels on daily gain, body composition and reproductive performance of gilts.At 118 (sem=0.28) days old, 54 genetically lean gilts ((Landrace x Large White) x Large White) were allocated, considering firstly age and secondly weight, between three treatments with different dietary lysine:energy (g/MJ DE) ratios: High (0.9), Medium (0.6) and Low (0.3), fed twice daily at 2.9 x maintenance energy. Animals were weighed weekly and backfat thickness (P2) and muscle depth values were also taken. Eye muscle area measurements were taken by real time ultrasonography (Aloka 500) at the end of the experiment At 160 days of age, puberty was induced by administration of exogenous gonadotropin (PG600).

Genetics of leg weakness in performance-tested boars

1983 ◽  
Vol 36 (1) ◽  
pp. 117-130 ◽  
Author(s):  
A. J. Webb ◽  
W. S. Russell ◽  
D. I. Sales
Keyword(s):  
Performance Index ◽  
Genetic Relationships ◽  
Genetic Correlations ◽  
Live Weight ◽  
Rapid Decline ◽  
Large White ◽  
Muscle Area ◽  
Eye Muscle ◽  
Leg Weakness ◽  
And Performance

ABSTRACTGenetic relationships among leg and performance traits were estimated for 23 975 Large White and Landrace boars fed twice daily to appetite from 27 to 91 kg live weight at Meat and Livestock Commission testing stations between 1966 and 1972. For each boar, an overall leg score was derived as the sum of scores for 19 individual leg traits categorized as ‘absent’ (0), ‘slight’ (1) or ‘severe’ (2) at 91 kg. Heritabilities of leg score were 017 ± 0·03 in Large White and 0·19 ± 0·04 in Landrace. Genetic correlations with a visual ‘leg action’ score on a scale from 1 to 5 averaged 0·93 ± 0·02 over breeds. Genetic and phenotypic correlations between leg scores on the same boars at 27 and 91 kg averaged 0·50 ± 0·17 and 0·15 ± 0·01 respectively.Both breeds showed significant adverse genetic correlations ranging from 0·20 ± 0·10 to 0·40 ± 0·08 between leg score and boar ultrasonic backfat. From slaughtered littermates, leg scores showed favourable genetic correlations with eye-muscle area (0·30 ± 0·10) and killing-out proportion (0·35 ± 011) in Large White and unfavourable correlations with carcass length (0·31 ± 0·10), lean content (0·30 ± 0·14) and backfat (0·33 ± 0·11) in Landrace. There were no associations with growth rate, feed efficiency or the performance index on which boars are selected. The study indicates that leg condition and fatness are adversely genetically related, but that selection on the present national performance index would not be expected to cause a rapid decline in leg condition. Culling on leg score would be expected to reduce the frequency of leg weakness.

The comparative performance of purebred and crossbred boars in commercial pig production

1975 ◽  
Vol 21 (1) ◽  
pp. 69-75 ◽  
Author(s):  
W. B. Lishman ◽  
W. C. Smith ◽  
M. Bichard ◽  
R. Thompson
Keyword(s):  
Carcass Traits ◽  
Live Weight ◽  
Large White ◽  
Muscle Area ◽  
Comparative Performance ◽  
Eye Muscle ◽  
Pig Production ◽  
Performance Differences ◽  
Per Se

SUMMARYAn investigation was undertaken to evaluate the crossbred boar per se, and also to assess the value of including the American Hampshire into a first-cross sire. Groups of three boars were placed on each of 20 farms. Each group contained a purebred white (Landrace or Large White), a crossbred white and a crossbred Hampshire boar. Co-operators were asked to obtain at least six litters by each boar, record their performance to weaning, and provide a sample of the progeny of each boar to be reared under standard conditions to slaughter at 90 kg live weight. Breeding of the boars did not affect either the level or variability of litter performance. Differences in performance and carcass traits between the progeny of purebred and whitecross boars were found only for ‘eye-muscle’ area and fat depth ‘C’. Pigs sired by Hampshire-cross boars had carcasses which were 2% shorter than those from white boars.

scholarly journals Sire Effects on Carcass of Beef-Cross-Dairy Cattle: A Case Study in New Zealand

Animals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 636
Author(s):  
Natalia Martín ◽  
Nicola Schreurs ◽  
Stephen Morris ◽  
Nicolás López-Villalobos ◽  
Julie McDade ◽  
...  
Keyword(s):  
New Zealand ◽  
Dairy Industry ◽  
Live Weight ◽  
Carcass Weight ◽  
Progeny Testing ◽  
Meat Color ◽  
Muscle Area ◽  
Eye Muscle ◽  
Beef Breed ◽  
Color Score

There is interest in increasing the carcass value of surplus calves born in the dairy industry that are reared for beef production in New Zealand. This experiment evaluated the carcass of Angus and Hereford sires via progeny testing of beef-cross-dairy offspring grown on hill country pasture. Weight and carcass traits were analyzed from 1015 animals and 1000 carcasses of 73 sires. The mean of the progeny group means was 567 kg for live weight at slaughter, 277 kg for carcass weight, 48.9% for dressing-out, 240.3 cm for carcass length, 73.6 cm2 for eye muscle area, 7.4 mm for rib fat depth, 0.91 for marble score, 3.05 for fat color score, 3.01 for meat color score, and 5.62 for ultimate pH. Sire affected (p < 0.05) carcass size and fat traits, but not fat color, meat color, or ultimate pH (p > 0.05). There was a 46 kg increase in carcass weight between the best and worst sires tested. Carcass fat traits were the most variable among sires. The use of genetically superior beef-breed sires over dairy-breed cows has the potential to increase carcass weights from surplus calves born in the dairy industry, while maintaining adequate fat levels and carcass quality.

scholarly journals Association Among Some Carcass Traits In Three Weight Groups Of Pigs

2021 ◽  
Vol 2 (2) ◽  
pp. 165-181
Author(s):  
B. L. Fetuga ◽  
G. M. Babatunde ◽  
O. Ayeni ◽  
V. A. Oyenuga
Keyword(s):  
Carcass Traits ◽  
Regression Equations ◽  
Linear Measurements ◽  
Large White ◽  
Muscle Area ◽  
Eye Muscle ◽  
Predictive Values ◽  
Slaughter Weight ◽  
The Relationship ◽  
Weight Groups

A TOTAL of seven hundred and eight Large White x Landrace pigs were slaughtered at three weight groups, 34.0, 55.0 and 92.0kg to collect carcass data. Of these 228, made of 118 castrates and 110 gilts, were slaughtered at 34 kg; 240 pigs, made up of 125 castrates and 115 gilts were slaughtered at 55kg, while a total of 240 pigs made up of 120 gilts and 120 barrows were slaughtered at 92 kg. Simple correlations as well as regression equations describing relationship among traits were calculated.  Percent of lean cuts and separable lean in carcass decreased while fat cuts and separable fat increased with increasing slaughter weight. Such linear measurements as backfat thickness, loin-eye muscle area and carcass length increased significantly with increasing slaughter weights. Significant differences were obtained for several carcass traits between castrates and gilts slaughtered at 92 kg. Among the carcass cuts, percentage four lean cuts and loin showed highly significant and positive correlations with separable lean, while the relationship for other cuts such as the ham and shoulder, though significant, were low. Such carcass fat predictors as percentages separable fat, fat cuts and trimmed fat as well as back at thickness were highly significantly negatively correlated with separable lean, the relationship being highest for percentage separable fat. Dressing percentage and carcass length were poorly correlated with fatness or leaness, while loin eye areas was highly significantly correlated with leaness. The predictive values of the different traits remained relatively the same at the different slaughter weights, although the relationships were better at the 55 kg slaughter weight than at lower weights. The results indicate that while direct chemical determinations or complete physical separation are considered the best measures of carcass quality, the magnitude of the correlation coefficients between separable lean or fat and the different cuts suggests that these could be used with some degree of precision in appraising carcasses.

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