Slaughter Season Research Articles

A survey comparing meat quality attributes of beef from credence attribute-based production systems

Markus, S. B., Aalhus, J. L., Janz, J. A. M. and Larsen, I. L. 2011. A survey comparing meat quality attributes of beef from credence attribute-based production systems. Can. J. Anim. Sci. 91: 283–294. Two branded beef programs based on producer-defined production systems differentiated by intangible credence attributes (Organic and Natural) were compared with Commodity beef to determine meat quality and assess consumer acceptability. In each of four slaughter seasons (winter, spring, summer and fall) longissimus lumborum muscle samples were collected from two industry slaughter plants; Organic n=30, 30, 27 and 31; Natural n=30, 27, 29 and 25; Commodity 1 n=12 and 18 for spring and summer, respectively; Commodity 2 n=14 and 12 for spring and fall, respectively. Samples were vacuum packaged and aged for 16±2 d at 2°C. Seasonal effects (P<0.01) were evident for mean shear force, composition, drip loss, colour and pH. While all mean shear values were classified as being tender (<5.6 kg), a smaller proportion of steaks were classified as tender in the Organic beef compared with the Natural and Commodity beef (55.9 vs. 70.3 and 78.6%; P<0.01), indicating that even after industry normal ageing times there was higher tenderness variability in the Organic beef. Fat content (SEM=0.23; P<0.01) was lowest for the Organic line (3.98%) with Natural (5.34%) and Commodity being intermediate (5.73%). Some statistically significant differences (P<0.05) in mean scores for aroma, juiciness, flavour, tenderness and overall acceptability of cooked beef steaks were observed amongst the three production systems when samples were not matched on the basis of intramuscular fat (IMF). Clearly there are measureable differences in quality between “credence” based production systems and commodity beef with an overall better quality in Commodity beef. However, if the consumer is willing to pay for credence-based attributes then there is an opportunity for these production systems to improve the quality of their product, specifically in respect to age at slaughter and content of IMF.

Meat quality defined based on pH and colour depending on cattle category and slaughter season

The studies were carried out on 614 animals slaughtered in winter and summer seasons. After slaughter and post-slaughter processing the carcasses were evaluated according to EUROP system. The meat pH and its colour were determined in m. longissimus thoracis after 48 hours of chilling. A significant effect of cattle category, season of slaughter and interactions between them on meat pH was found. High pH values were observed mainly in the summer season in the groups of young bulls (A) (6.1) and bulls (B) (6.07). Slightly lower values 5.94 and 5.65, respectively, were observed in both above-mentioned groups in winter. Meat collected from heifers was characterized by proper pH in both analysed seasons whereas meat obtained from cows had pH values above 5.8, independently of the season of slaughter. The differences in colour lightness L* observed among all analysed cattle categories were statistically highly significant (P < 0.0001). The brightest red meat was obtained from heifers and the darkest from cows. The differences between young bulls and bulls in the same slaughter seasons were not large despite considerable variation in the age of slaughtered animals, especially in the summer season. Distinctly higher values of L* (brighter red meat) were found in the winter season in all cattle categories excluding meat from cows in which L* in summer was slightly higher than in winter. The differences in L* between seasons as well as the interaction of cattle category × slaughter season were statistically highly significant (P < 0.0001). For the remaining colour parameters (a*, b*) higher values were also observed in winter compared to summer in all cattle categories. The highest values of a* and b* were found in bulls.

The quality characteristics of M. longissimus from Hanwoo (Korean cattle) steer with different raising altitudes and slaughter seasons

The quality characteristics of M. longissimus from Hanwoo steer with different raising altitudes and slaughter seasons were studied. The experiment used factorial design with raising altitude and slaughter season as treatments. Forty eight steer were raised in two groups of raising altitude, i.e. 100 m of altitude (low) and 700 m of altitude (high), and were slaughtered in two groups of slaughter season, i.e. the end of September (summer) and the end of March (winter). The initial age of cattle was 22 months and they were raised for six months prior to slaughter. At 48 h post-slaughter, the samples were collected for meat quality analyses. Part of samples was stored at 2 ± 0.2 °C for 9 days for lipid and myoglobin stabilities. Meat from high raising altitude had lower ( P < 0.05) saturated fatty acids and higher ( P < 0.05) unsaturated fatty acids concentrations than that from low altitude. Polyunsaturated fatty acids n-6/n-3 of meat from summer slaughter season were significantly lower ( P < 0.01) than that from winter season. The pH of meat from high raising altitude was significantly higher ( P < 0.05) than that from low altitude and that from summer slaughter season was significantly higher ( P < 0.001) than that from winter season. Aroma and tenderness scores of meat from summer slaughter season were significantly higher ( P < 0.05) than those from winter season. There were no significant difference TBARS values of meat between two raising altitudes and two slaughter seasons during storage from summer was significantly higher ( P < 0.05) than that from winter slaughter season. At 9 days of storage, the oxymyoglobin concentration at the surface of meat from high raising altitude was significantly lower ( P < 0.01) than those from low raising altitude and the metmyoglobin concentration at the surface of meat from high raising altitude was significantly higher ( P < 0.01) than those from low altitude. There was no significant difference in oxymyoglobin and metmyoglobin concentrations at the surface of meat between two slaughter seasons during storage. Different raising altitudes affected fatty acid composition, pH and myoglobin stability during refrigerated storage. Different slaughter seasons affected fatty acid composition, pH and sensory properties without any effects on lipid and myoglobin stabilities during refrigerated storage.

Carcass characteristics of Hanwoo (Korean cattle) from different sex conditions, raising altitudes and slaughter seasons

This study was carried out to investigate the carcass characteristics of Hanwoo (Korean cattle) from different sex conditions, raising altitudes and slaughter seasons. The total number of cattle used in this study was 3608 heads which comprised of 1336 bulls and 1660 steers. The data was analyzed according to sex condition (bull and steer), raising altitude (low: 0–100 m and high: 700–800 m) and slaughter season (spring, summer, autumn and winter). At 24 h post-slaughter, the carcasses were weighed and evaluated for carcass traits according to the Korean carcass grading standard by an official grader. Carcass weight, ribeye area, yield index and grade, and meat color, firmness and maturity scores of carcass from bulls were significantly higher ( P < 0.001) than those from steers. Inversely, the backfat thickness, marbling score and quality grade of carcass from steers were significantly higher ( P < 0.001) than those from bulls. The maturity score of carcass from a high area was significantly higher ( P < 0.01) than that from a low area. The ribeye area of carcass from summer was significantly smaller ( P < 0.05) than that from other seasons. The maturity score of carcass from the summer season was highest among that from other seasons and the lowest was that from the winter season. Marbling score and carcass quality grade from the winter season were highest among those from other seasons and the lowest were those from the autumn season. There were no significant interactions between sex condition and raising altitude on carcass traits except the ribeye area. There were significant interactions between sex condition and slaughter season on marbling score and carcass quality grade. There were no significant interactions between raising altitude and slaughter season on all of the carcass traits. There were significant interactions among sex condition, raising altitude and slaughter season on meat color score. It was concluded that sex condition affected muscle and fat depositions on the carcass, raising altitude affected maturity and slaughter season affected ribeye area, maturity and marbling.

Raw bovine meat fatty acids profile as an origin discriminator

Consumers are very concerned in “Protected Designation of Origin” (PDO) products, namely meat, since they associate these products to quality and healthy foods. Thus, it is necessary to implement analytical methodologies that could assure consumers about the products they purchase. Since this kind of meat is usually sold with no information concerning cattle sex, age and slaughter season, these characteristics were intentionally not taken into account. In this study, two Portugueses PDO bovine breeds (Mirandesa and Barrosã) and two production sub-systems (traditional and organic farming) were studied during a two-year period. Statistical analysis showed that production system and breed had a significant effect on the overall raw meat fatty acids (FA) content. Besides, the FA profiles could be used as an effective tool to differentiate the four groups studied allowing a 100% correct classification. The meat FA content was also correlated with the relative importance of the animal feeding stuff area.

Quantification of the relative efficiency of factory surveillance in the disclosure of tuberculosis lesions in attested Irish cattle

In Ireland, factory surveillance of cattle for gross lesions is an important supplementary method for detecting herds infected with bovine tuberculosis (tb), and in recent years between 27 and 46...

Influence of slaughter season and muscle type on fatty acid composition, conjugated linoleic acid isomeric distribution and nutritional quality of intramuscular fat in Arouquesa-PDO veal

The effects of the slaughter season and muscle type on lipid and conjugated linoleic acid (CLA) contents, fatty acid composition and isomeric profile of CLA in Arouquesa veal, from calves reared according to the specifications of the protected designation of origin (PDO), were assessed. Arouquesa purebred calves ( n = 31) were raised in a traditional production system, slaughtered in early autumn (October) or late spring (June), and the longissimus dorsi and semitendinosus muscles were sampled for analysis. Arouquesa-PDO veal only showed seasonal differences in the levels of some minor fatty acids (16:1c9, 17:1c9, 18:1t, 18:3 n − 3, 20:0 and 22:4 n − 6) and CLA isomers (t12,t14, t9,t11 and c11,t13). Furthermore, significant interactions between the slaughter season and muscle type were obtained for several fatty acids and CLA isomers, total lipids and CLA, and the PUFA/SFA ratio. In both seasons, veal-PDO depicts values of pasture-fed cattle. From a human nutritional perspective, veal-PDO in both slaughter seasons has relatively high CLA contents and percentages of the c9,t11 CLA isomer, which is favourable, while the n − 6/ n − 3 ratios are within the recommended values for the human diet. In conclusion, the results suggest that intramuscular fat in Arouquesa-PDO veal has high nutritional value throughout the year.

Effect of slaughter season on fatty acid composition, conjugated linoleic acid isomers and nutritional value of intramuscular fat in Barrosã-PDO veal

This paper describes the influence of slaughter season on lipid content, fatty acid composition, conjugated linoleic acid (CLA) isomeric profile and nutritional value of fat in Barrosã veal from calves reared according to the specifications of the Protected Designation of Origin (PDO). Barrosã purebred calves ( n = 27) were raised in a traditional production system and slaughtered in early autumn (October) and late spring (June). Barrosã-PDO veal only presented seasonal differences in the levels of some minor fatty acids and CLA isomers, as well as in the PUFA/SFA ratio. Based on the analysed grass intake indicators, it was shown that veal-PDO has similar values to pasture-fed cattle for both slaughter seasons. From a human nutrition perspective, intramuscular fat in Barrosã-PDO veal has a high nutritional value throughout the year, since CLA contents and the percentages of the c9,t11 isomer are relatively high, and the n − 6/ n − 3 ratios are within the recommended values for the human diet.

Influence of slaughter season and sex on fatty acid composition, cholesterol and α-tocopherol contents on different muscles of Barrosã-PDO veal

The influence of slaughter season and sex on intramuscular total lipids (ITL) neutral lipid (NL) and phospholipid (PL) compositions, cholesterol and α-tocopherol contents were evaluated in Biceps femoris (Bf), Longissimus dorsi (Ld) and Supraspinatus (Ss) muscles from 92 Barrosã-PDO (Protected Denomination of Origin) calves. ITL content in Bf muscle was affected by slaughter season and sex whereas NL content was only affected by slaughter season. Neither sex nor slaughter season influenced cholesterol and α-tocopherol contents in the muscles under study. Concerning NL composition, sex was an important source of variation on the proportions of total SFA and MUFA in all muscles. Irrespective of the considered muscle, males had higher total SFA but lower total MUFA and MUFA/SFA contents than females. Slaughter season influenced C18:2 cis-9 trans-11 (CLA) content in Bf ( P < 0.01) and in Ss muscles ( P < 0.05) with calves slaughtered in autumn showing higher values than their counterparts. Total MUFA, n-3 PUFA and n-6/ n-3 ratio contents in Ld muscle were also affected by slaughter season. Regarding PL composition, slaughter season × sex interaction affected total SFA, PUFA/SFA and n-6 PUFA contents in Bf and Ss muscles. In addition, this interaction influenced total MUFA ( P < 0.05) in Bf muscle and total PUFA ( P < 0.01) in Ss muscle. CLA content in PL from Ld was influenced by sex ( P < 0.05) and by slaughter season ( P < 0.01), with females slaughtered in autumn presenting the highest content. These results clearly indicate that sex and slaughter season are important factors that influence the fatty acid composition of Barrosã-PDO veal.

Carcass Traits Determining Quality and Yield Grades of Hanwoo Steers

A group of Hanwoo (Korean cattle) steers (n=14,386) was sampled from a commercial abattoir located in Seoul over one year period (spring, summer, autumn and winter) and their carcass traits were collected. Carcass traits assessed by an official meat grader comprised degree of marbling, meat color, fat color, texture and maturity for quality grade, and back fat thickness, ribeye area and carcass weight for yield grade. A heavier carcass with a higher marbling score, more red meat color and white fat color received better quality grade (p<0.05). Regression analysis showed that the marbling score was the strongest attribute (partial R 2 =0.88) for quality grade. Lighter carcasses with a thinner back fat and larger ribeye area received higher yield grade score. The back fat thickness was the most negative determinant of yield grade (Partial R 2 =-0.66). The slaughter season had a little effect on quality and yield grades. As slaughter weight increased, back fat thickness and ribeye area increased linearly, whereas marbling score reached its asymptotic level at approximately 570 kg. As a consequence, quality grade showed a considerable improvement up to 570 kg, but increases in slaughter weight afterward showed a little benefit on quality grade. There was a clear curvilinear relationship between slaughter weight and yield grade in that the yield grade reached its highest point at approximately 490 kg and decreased afterward. These results suggested that 570 kg at the age of 24 months might be the economic slaughter weight for quality grade but 490 kg for yield grade.

Effect of different genotypes, sires and season of slaughtering on slaughter traits of pigs

The effect of different genotypes, sires and season on age at slaughtering mass of warm carcass sides, fat thickness measured on three points (withers back, rump) and percentage of meat in warm carcass sides of average mass of 74,17kg using Yugoslav standard method was investigated in this paper. Results obtained show that investigated traits had no variation between pigs of different genotype (P&gt;0,05). Sires effected variation of age at slaughtering, fat thickness (withers, back, rump, back + rump) and percentage of meat in warm carcass sides of offspring (P&lt;0,01). Slaughter season effected fat thickness measured on withers (P&lt;0,01) and age at slaughtering (P&lt;0,05). Age, fat thickness and percentage of meat depended on the mass of warm carcass sides. Evaluated heritability coefficients for investigated traits were in interval of medium to high.

Changes in carcass composition with age in 16-26 month old Red Deer

Modern retailing of venison through supermarkets requires that the product be on the shelf for an extended period compared with the traditional short season in autumn/early winter. However, deer are highly seasonal animals and a range of strategies is needed to increase marketing opportunities for venison. One strategy utilizes extended winter daylength and high levels of nutrition to advance the slaughter season (Davies, 1995; Fisher et al., 1995). Another strategy is to adopt more natural, low input systems with reduced production costs, in which deer reach slaughter condition during their third summer at 22-26 months of age, but this needs full investigation. This study involved sequential slaughtering of deer to ascertain how rapidly carcass composition and meat quality changes over this period.

Hypobiosis in the ostertagids of red deer and the efficacy of ivermectin and fenbendazole against them

An abattoir survey was carried out during the 1991 to 1992 slaughter season to examine the structure of the ostertagid populations in red deer. Most of the animals were 15-...

Carcass weights of cattle in relation to breed, sex, age, region of origin and season

Effects on carcass weights of region of origin, season and year of slaughter, breed, sex, age and pregnancy status were examined for 4229 cattle slaughtered in selected Australian abattoirs in 1973 and 5708 cattle in 1977-78. For non-pregnant cows slaughtered in 1973, the relationship between carcass weight and presence of cyclic activity of the ovaries was examined at slaughter. Data from abattoirs in Rockhampton, Mackay and Townsville are also presented on carcass weights of about 641 000 cattle killed from January 1977 to November 1979. In 1977-78, at abattoirs in northern, central and eastern Australia, carcass weights of slaughtered bulls averaged 269 kg, steers 263 kg and cows 188 kg, compared with mean carcass weights of 263, 276 and 186 kg for all bulls, steers and cows killed in 3 northern Queensland abattoirs during 1977-79. Cows slaughtered in north-eastern Australian abattoirs in 1973 averaged 160 kg. After adjusting for breed, sex and age differences, carcass weights of cattle slaughtered in 1977-78 differed by region of origin, with greater weights from subtropical than from northern tropical and coastal regions; and by season of slaughter, with lowest weights being recorded in spring. Carcass weights of cows from tropical regions and slaughtered in 1973 increased by 10 kg (British breed), 32 kg (Brahman) and 69 kg (British x Brahman), as age increased from 2 to 5 years. With increased age beyond 5 years, carcass weights of these cows decreased. Conversely, carcass weights of British breed cows reared in subtropical regions and slaughtered in 1977 increased by 37 kg throughout the 2-12 year age range. After adjusting for breed, age, season and regional differences, mean carcass weights of non-pregnant, cycling cows and cows grouped according to trimester of pregnancy were not different. Carcass weights of cows which were non-pregnant and non-cycling were 12 kg less than cows which were non-pregnant but cycling. Cycling prevalence in Brahman cows exceeded those of British breed or British x Brahman cows from northeastern Australia, when compared at the same age and carcass weight. Age had no effect on cycling prevalence when cows were compared at the same carcass weight.

Influence of handling systems on meat quality of beef and some remarks concerning slaughter handling of reindeer

The combined effects of corral design and corral time on the incidence of D F D (dark, f i rm, dry meat) in young bulls and calves ( C . W . 100-110 kg) has been studied in two projects compris ing about 1800 young bulls and 600 calves. Three different types of corral design were tested individual pens, large free-range pens (6-10 animals per pen), and tethering. F o r each corral type, various holding periods were studied. The use of a so-called delivery-pen at the producer ' s was also evaluated. The delivery-pen is used for the holding of animals destined for slaughter w h i c h are gathered the day before del ivery in order to assist the transporter and to make loading a one-man job. In the calf project a l o w ceiling in the corral to prevent mount ing was tested. The ultimate p H ( p H u ) was measured in several muscles. Muscles w i t h 5.80 = p H u 6.20 as D F D . The main result can be summarized: In Sweden D F D is the most c o m m o n meat quality deficiency in beef and veal. The shelf life and the frying characteristics w i l l be reduced. The use of individual pens vis-a-vis large freerange pens resulted in a considerably reduced incidence of D F D meat. L o n g holding periods (i.e. overnight) versus short periods in individual pens caused a minor increase in D F D incidence. A corresponding comparison for large pens resulted i n a very substantial increase. W h e n young bulls that had been tethered at the producer ' s were kept tethered overnight in the corral p r io r to slaughter, hardly any D F D meat was found. The use of a delivery-pen caused a dramatic increase in D F D incidence. N o more than 4-5 calves should be housed in a pen, especially if they have to be fenced overnight. The ultimate p H was clearly reduced by lowering the ceiling in the calf-corral to prevent mount ing . The results have been used in the Swedish slaughter industry since 1985. The D F D incidence has been reduced to a m i n i m u m . Based on our results and results f rom F i n n i s h studies on reindeer it is possible to give some theoretical and concluding remarks concerning slaughter handling of reindeer. It w o u l d be recommendable to: shorten the slaughter handling procedure as much as possible. Especially the handling moments of individual animals. move the abattoir to the reindeer instead of mov ing the animals to the slaughter house. slaughter the reindeer during the autumn season. The D F D incidence increases dramatically dur ing the winter season when the animals often w i l l be in a negative energy balance. introduce electrical st imulation of the carcasses to avoid the prob lem of co ld shortening. F i n a l l y , to present detailed recommendations h o w to handle reindeer at slaughter ensuring (i) opt imal meat quality and (ii) proper animal welfare it is necessary to study the various moments i n the slaughter chain and during different slaughter seasons. 16 Rangif er, Special Issue No . 5, 1990

The distribution and prevalence of stephanofilariasis in cattle in Queensland.

A total of 10,543 cattle from 1,386 farms throughout Queensland was examined at abattoirs and the presence of stephanofilarial lesions was related to property of origin, sex, breed, and age of the slaughtered cattle and season of slaughter. The mean prevalence was 38% and within the infected area this varied from less than 5% in south east Queensland to 95% on Cape York Peninsula. The prevalence of lesions was higher in bulls than in steers [corrected] and was least in cows [corrected]. Bos indicus animals had a lower prevalence than B. taurus. Prevalence increased with age. The distribution of the disease closely matched that of the buffalo fly, Haematobia irritans exigua.

Relationships Between Endogenous Gonadotropin-Releasing Hormone, Gonadotropins, and Follicular Development After Weaning in Sows1

Two experiments were conducted to examine relationshipsbetween endogenous gonadotropinreleasing hormone (GnRH), concentrations of gonadotropins in the anterior pituitary and blood and ovarian follicular development in weaned sows. In the first experiment, 48 sows were slaughtered during 0 to 5 days after weaning. Because effects of breed, parity, farm and season of slaughter were confounded with day after weaning, data were analyzed solely on the basis of follicular development. Sows were divided into 4 groups based on the size and number of the largest ovarian follicles. Group 1 consisted of 11 sows with largest follicles 14) follicles 5 to 10mm in diameter. Group 4 coniisted of sows (n=12) with follicles>10 mm in diameter. Data from 3 sows that had ovulated were omitted from the analyses.Sows in Groups 1,2, 3 and 4 were killed atm average of 0.7 ± 0.4, 2.5 * 0.2,4.7 ± 0.1 and 4.8 ± 0.2 days after weaning, respectively. Concentrations of GnRH in medial basal hypothalamus (MBH), stalk median eminence (SME) and hypophyseal portal area (HPA) were greater in sows with greater follicular development (Groups 3 and 4). Concentrations of luteinizing hormone (LH) in anterior pituitary (AP) and serum were also greater in Groups 3 and 4. Concentrations of follicle-stimulating hormone (FSH) in AP and serum were not significantly different among groups. In the second experiment, 27 second parity Duroc sows were slaughtered 0, 60 or 96 h after weaning (9 sows per group). Concentrations of both LH and FSH in serum samples obtained at 6-h intervals from weaning to slaughter increased after weaning, and by 96 h levels of LH indicated a preovulatory surge was beginning. Follicular diameter increased with time after weaning, with increases in number of follicles >5 mm in diameter, and decreases in number of follicles <5 mm in diameter. Concentrations of LH, but not FSH, in AP were greater at both 60 and 96 h than at 0 h after weaning (P<0.01). Concentrations of GnRH in MBH and SME were greater at 60 and 96 h than at 0 h (P<0.05). The concentration of GnRH in HPA was increased only at 96 h after weaning. In both experiments, concentration of GnRH increased after weaning, concurrently with postweaning increases in serum FSH, serum and pituitary LH and follicular development. Thus we propose that initiation of estrus and ovulation after weaning may be associated with changes in production of GnRH.

Effect of carcass traits on carcass prices of holstein steers in Korea.

The present study investigated the contribution of carcass traits on carcass prices of Holstein steers in Korea. Phenotypic data consisted of 76,814 slaughtered Holsteins (1 to 6 yrs) from all over Korea. The means for live body weight at slaughter (BWT), chilled carcass weight (CWT), dressing percentage (DP), quantity grade index (QGI), eye muscle area (EMA), backfat thickness (BF) and marbling score (MS), carcass unit price (CUP), and carcass sell prices (CSP) were 729.0 kg, 414.2 kg, 56.79%, 64.42, 75.26 cm2, 5.77 mm, 1.98, 8,952.80 Korean won/kg and 3,722.80 Thousand Korean won/head. Least squares means were significantly different by various age groups, season of slaughter, marbling scores and yield grades. Pearson’s correlation coefficients of CUP with carcass traits ranged from 0.12 to 0.62. Besides, the relationships of carcass traits with CSP were relatively stronger than those with CUP. The multiple regression models for CUP and CSP with carcass traits accounted 39 to 63% of the total variation, respectively. Marbling score had maximum economic effects (partial coefficients) on both prices. In addition, the highest standardized partial coefficients (relative economic weights) for CUP and CSP were calculated to be on MS and CWT by 0.608 and 0.520, respectively. Path analyses showed that MS (0.376) and CWT (0.336) had maximum total effects on CUP and CSP, respectively; whereas BF contributed negatively. Further sub-group (age and season of slaughter) analyses also confirmed the overall outcomes. However, the relative economic weights and total path contributions also varied among the animal sub-groups. This study suggested the significant influences of carcass traits on carcass prices; especially MS and CWT were found to govern the carcass prices of Holstein steers in Korea.