Lower Warner-Bratzler Shear Research Articles

Impact of ractopamine hydrochloride on growth performance, carcass and pork quality characteristics, and responses to handling and transport in finishing pigs.

The effect of feeding ractopamine hydrochloride (RAC) on growth performance, carcass and pork quality, and blood acid-base and catecholamine responses to handling and transport in finishing pigs was evaluated using a randomized complete block design to compare 2 RAC levels (0 vs. 10 mg/kg). Crossbred pigs ( = 144) were housed in single-sex pens (barrow or gilt) of 3 with 24 pens/RAC level. The study was carried out for a 28-d period from 104.0 ± 5.99 to 136.7 ± 6.44 kg BW. At the end of the growth study, pigs were subjected to handling and transport procedures that involved an initial aggressive handling procedure (pigs moved 50 m with 8 shocks from an electric prod) followed by a 30-min transport on a standard livestock trailer at a floor space of 0.46 m/pig followed by a final gentle handling procedure (pigs moved 100 m using sort boards and slap paddles). A blood sample was taken and rectal temperature was measured 2 h before (baseline) and immediately after the final handling procedure (final). Barrows ( = 72) were harvested and carcass and pork quality were measured. Feeding RAC increased ( ≤ 0.05) ADG (19.6%), ADFI (4.2%), and G:F (14.8%). The increase in plasma epinephrine levels from baseline to final was greater ( ≤ 0.05) for pigs fed RAC; there was a trend ( ≤ 0.10) for pigs fed RAC to have greater final blood lactate and to show a greater change from baseline to final in blood bicarbonate, partial pressure of and total carbon dioxide, and oxygen saturation levels. However, there were no differences between treatments for changes from baseline to final in rectal temperature, blood pH and lactate, and plasma norepinephrine levels. The incidence of physical indicators of stress and of nonambulatory, noninjured pigs during the handling and transport procedures was similar for the 0 and 10 mg/kg RAC levels. Final farm BW was 4.1 kg heavier, carcass yield was 1.4 percentage units greater, and LM area was 5.18 cm greater for pigs fed RAC compared to the control ( ≤ 0.05). Minolta a* and b* values were lower ( ≤ 0.05) and ultimate pH (0.05 units) and Warner-Bratzler shear force (0.43 kg) were greater ( ≤ 0.05) for pigs fed 10 compared to 0 mg/kg RAC. These results confirm the substantial improvement from feeding 10 mg/kg RAC in growth performance and carcass yield and suggest relatively limited effects on pork quality and on responses to the handling and transport procedures used in this study.

Short Communication: Tenderness of suckler beef produced in British Columbia

Hartling, I., Cinel, B., Donkor, K. K., Ross Friedman, C., Paetkau, M. J. and Church, J. S. 2014. Short Communication: Tenderness of suckler beef produced in British Columbia. Can. J. Anim. Sci. 94: 295–298. In order to investigate the potential of suckler beef production in British Columbia, shear force values were determined using Warner–Bratzler shear (WBS) force tests on 10 major muscles obtained from suckler-raised Simmental cattle along with the longissimus thoracis from grain- and grass-fed cattle of similar breeding. Shear force values obtained for suckler beef were then compared with literature values from grain-fed beef. All suckler beef muscles except the psoas major and spinalis dorsi had lower WBS values than their grain-fed counterparts from literature values, while the longissimus thoracis was shown to have equal tenderness in all three production systems. Results suggest that a higher number of muscles from suckler beef in this study could be used as steaks than is typically observed in the North American beef industry.

Effect of Potato By-products Based Silage on Growth Performance, Carcass Characteristics and Fatty Acid Composition of Carcass Fats in Holstein Steers

Ten 18.5-month old Holstein steers were allocated into two diet groups of five and fed either concentrates as control group or potato by-products based silage (PBS) as experimental group for six months to investigate the effect of PBS on growth performance, carcass characteristics and fatty acid composition of carcass fats. The PBS diet consisted, in a DM basis, of 74.5 %P BS, 16% hay, and 9.5% soybean milk residue (SMR). The control diet consisted, in a DM basis, of 82.5% concentrates and 17.5% hay. There were no significant differences in the overall average daily gain (ADG), dry matter intake (DMI), feed efficiency, yield score and meat quality score of dressed carcass between the two diet groups. There were no statistical differences in DM, crude protein (CP), and ether extract (EE) of beef and melting point of all adipose tissues from steers fed both diets. The PBS-fed steers tended to have lower Warner Bratzler shear (WBS) values than in the concentrate-fed steers (13.0 vs. 17.7 lb, p<0.1). At both sampling times 3 and 6 months of feeding period, PBS-fed steers had higher proportions of polyunsaturated fatty acids (PUFA), especially linoleic (C18:2) acids in subcutaneous fat than in control group (p<0.05). PBS-fed steers had significantly higher proportions of PUFA, especially C18:2 fatty acids than in concentrate-fed steers in carcass fats (p<0.05). In conclusion, feeding PBS to fattening steers has shown to have the same potential as concentrate feeding in terms of effect on the growth performance, feed efficiency, and carcass characteristics. Interestingly, PBS also seems preferable to concentrates because it increased the proportion of C18:2 fatty acid composition of carcass fats which is valuable for beef consumers. (Asian-Aust. J. Anim. Sci. 2005. Vol 18, No. 4 : 490-496)

Influences of aging on tenderness and color of beef steaks (2001)

Aging loin strip, bottom, and eye of round steaks for 21 days decreased Warner- Bratzler Shear (WBS) values (increased tenderness). For the top round, aged semimembranosus muscle steaks tended to have lower WBS values (more tender) than nonaged steaks, while aged adductor steaks were similar to non-aged steaks. Furthermore, instrumental L* color values were higher (lighter) for aged strip and eye of round steaks than non-aged steaks, and instrumental a* color values were higher (redder) for aged bottom round, eye of round, and top round (semimembranosus) steaks than nonaged steaks. Aging steaks is effective for improving tenderness and color of strip, bottom, top (semimembranosus) and eye of round steaks.

The effects of quality grade, postmortem aging, and blade tenderization on Warner-Bratzler shear force and cookery traits of biceps femoris steaks (2001)

We used 108 top sirloin butts to determine the influence of quality grades, postmortem aging periods, and blade tenderization passes on percentages of thawing and cooking losses and Warner-Bratzler shear (WBS) force of biceps femoris muscles. Top sirloin butts that qualified for either USDA Select (SEL, n=36), USDA Choice (CHO, n=36), or Certified Angus BeefTM Program (CAB, n=36), were aged for 14 or 21 days and blade tenderized zero (0X), one (1X), or two (2X) times. Steaks with higher quality grades (CHO and CAB) aged for 21 days had lower thawing losses than steaks aged 14 days and than SEL steaks aged for 21 days. Steaks aged for 14 days and not blade tenderized (0X) had higher thawing losses than steaks aged for longer periods (21 days) and tenderized 0X, 1X, and 2X. Lower quality grade steaks (SEL) blade-tenderized 2X had longer cooking times than other quality grade×blade tenderization treatments. More blade tenderization passes (1X and 2X) for higher quality grades (CHO and CAB) appear to lower WBS values. The most tender treatments were CHO steaks blade tenderized 2X and CAB steaks blade tenderized 1X and 2X. Biceps femoris tenderness was inconsistent among all treatments, although aging, blade tenderization, and higher quality grades reduce variation. For reliable, acceptable quality this muscle should not be included in top sirloin butt steaks.

Growth, puberty, and carcass characteristics of Brahman-, Senepol-, and Tuli-sired F1 Angus bulls.

Postweaning growth, sexual development, libido, and carcass data were collected from two consecutive calf crops using 31 Brahman x Angus (B x A), 41 Senepol x Angus (S x A), and 38 Tuli x Angus (T x A) F1 bulls. Following weaning (by mid-September) and preconditioning, at the start of the study (late September) bulls were fed concentrate (three times each week at a rate equivalent to 4.5 kg/d) on bahiagrass pasture for approximately 250 d. At the start of the study and at 28-d intervals, BW, hip height, and scrotal circumference (SC) were measured. Concurrently at 28-d intervals, when the SC of a bull was > or = 23 cm, semen collection was attempted using electroejaculation. Ejaculates were evaluated for presence of first spermatozoa (FS), 50 x 10(6) sperm with at least 10% motility (PU), and 500 x 10(6) sperm with at least 50% motility (PP). After all bulls reached PP they were subjected to two libido tests. Carcass data were collected on all bulls (n = 110) and Warner-Bratzler shear (WBS) force values were assessed on a subset (n = 80). For both years, B x A bulls were heavier (P < 0.05) and taller (P < 0.05) than S x A and T x A bulls at the start and end of the study. However, breed type did not influence (P > 0.10) gain in BW or hip height during the study. Scrotal circumference of T x A bulls was larger (P < 0.05) than that of B x A or S x A bulls at the start of the study, but there was no effect (P > 0.10) of breed type by the end of the study. At PU and PP, B x A bulls were older (P < 0.05), heavier (P < 0.05), and taller (P < 0.05) and had larger (P < 0.05) SC than S x A and T x A bulls. Tuli x Angus bulls were younger (P < 0.05) than S x A bulls at PU and PP but had similar SC. Libido scores tended (P < 0.10) to be lower for B x A than for S x A and T x A bulls. Breed type affected (P < 0.05) carcass traits; B x A bulls had the heaviest (P < 0.05) hot carcass weight, greatest (P < 0.05) dressing percentage, larger (P < 0.05) longissimus muscle area than S x A bulls, and higher (P < 0.05) USDA yield grade than T x A bulls but greatest (P < 0.05) WBS force values. Breed type did not affect (P > 0.10) USDA quality grade. In conclusion, tropically adapted F1 bulls produced from Senepol (Bos taurus) and Tuli (Sanga) sires bred to Angus cows in Florida had lighter BW, shorter hip heights, and smaller carcasses than those from Brahman sires but reached puberty earlier and had higher libido scores and lower WBS force values.

Calcium chloride concentration, injection time, and aging period effects on tenderness, sensory, and retail color attributes of loin steaks from mature cows

Calcium chloride (CaCl2) injection effects on retail color changes and sensory traits of loin steaks from mature cows were studied. Left side strip loins (SL) of 10 carcasses were divided into three portions within .5 h postmortem. One was a control, and the other portions were injected with either 150 mM or 200 mM CaCl2. At 24 h postmortem, the chilled, right side SL was removed and the same treatments applied. Steaks from each treatment were evaluated for color changes during 5 d of retail display. Treatments were also divided into 7-d or 14-d aging periods. Warner-Bratzler shear (WBS) values and sensory evaluations of juiciness, tenderness, flavor intensity, flavor description, and overall palatability were obtained on all treatments. Concentration of CaCl2 had no effect on measures of color. However, injection at 24 h reduced colorimeter L values and visual color scores on d 1 and 2 of retail display and increased discoloration scores on d 3 (P < .05) compared with injection at .5 h. All steaks had greater than 40% discoloration when measured beyond d 3. Steaks aged 14 d exhibited significantly lower WBS values than steaks aged 7 d (P < .05). Injections of CaCl2 increased scores for juiciness, tenderness, and overall palatability, and aging improved tenderness, flavor intensity, flavor description, and overall palatability (P < .05). Cuts injected at 24 h had 8.3% and 8.8% higher yields than cuts injected at .5 h or controls, respectively (P < .05).(ABSTRACT TRUNCATED AT 250 WORDS)

THE EFFECT OF A PROGRESSIVE-RESISTANCE EXERCISE ON GROWTH, DEVELOPMENT AND MEAT QUALITY OF SHEEP

This study was conducted to determine the effect of a progressive-resistance jumping exercise on growth, development and meat quality in sheep. Exercised sheep did not differ from control sheep in their live animal performance or in the proportion of muscle, fat and bone in the carcass, indicating the low energy cost of this exercise. The use of platform jumps rather than hurdle jumps resulted in a significant contribution of muscles in the forelimbs to the jumping motion. As a result, flexors of the elbow joint were a significantly larger proportion of total muscle weight in the exercised sheep. Muscle samples from the vastus lateralis in exercised sheep had lower Warner-Bratzler shear (P = 0.09) and Kramer Press-Ground (P = 0.04) scores than their control counterparts. The reason for the increased tenderness as a result of exercise is unknown, but there was no evidence that it resulted from muscular hypertrophy. Key words: Sheep, exercise, body composition, tissue distribution, meat quality