Time filter

Source Type

Gardner G.E.,Australian Cooperative Research Center for Sheep Industry Innovation | Gardner G.E.,Murdoch University | Williams A.,Australian Cooperative Research Center for Sheep Industry Innovation | Williams A.,Murdoch University | And 9 more authors.
Meat Science | Year: 2015

Pre-slaughter live weight, dressing percentage, and hot standard carcase weight (HCWT) from the 2007, 2008, 2009 and 2010 birth-years of the Information Nucleus Flock Lambs (n. =. 7325) were analysed using linear mixed effects models. Increasing the sire breeding value for post-weaning weight (PWWT), and c-site eye muscle depth (PEMD), and reducing the sire breeding value for fat depth (PFAT) all had positive impacts on HCWT. The magnitude of the PWWT effect was greater in pure bred Merinos compared to Maternal and Terminal sired progeny. The improved HCWT resulting from increased PEMD was entirely due to its impact on improving dressing percentage, given that it had no impact on pre-slaughter live weight. There were marked differences between sire types and dam breeds, with pure-bred Merinos having lower pre-slaughter weight, reduced dressing percentage, and lower HCWT than progeny from Terminal and Maternal sired lambs or progeny from Maternal (1st cross) dams. © 2014 Elsevier Ltd.


Pannier L.,Australian Cooperative Research Center for Sheep Industry Innovation | Pannier L.,Murdoch University | Gardner G.E.,Australian Cooperative Research Center for Sheep Industry Innovation | Gardner G.E.,Murdoch University | And 9 more authors.
Meat Science | Year: 2014

The impact of selecting for lean meat yield using breeding values for increased eye muscle depth (PEMD) and decreased fat depth (PFAT) on the consumer acceptance of lamb meat was evaluated. Consumer sensory scores (tenderness, juiciness, flavour, odour, overall liking) were obtained for the longissimus lumborum (loin) and semimembranosus (topside) muscles of 1471 lambs. On average loin samples were more acceptable for consumers. Sensory scores increased with higher IMF levels, with lower shear force levels, and when animals were younger and less muscular. Increasing PEMD decreased tenderness, overall liking and flavour scores in both muscles, and decreasing PFAT reduced tenderness within the loin samples only. This negative impact of PEMD and PFAT is not solely driven through the phenotypic impact of IMF and shear force on sensory scores. Our results confirm the growing concerns that selecting for lean meat yield would reduce consumer eating quality, and highlight that careful monitoring of selection programmes is needed to maintain lamb eating quality. © 2013 The Authors.


Kitessa S.M.,Australian Cooperative Research Center for Sheep Industry Innovation | Kitessa S.M.,CSIRO | Young P.,Australian Cooperative Research Center for Sheep Industry Innovation | Young P.,CSIRO | And 8 more authors.
British Journal of Nutrition | Year: 2012

Vegetable oils containing stearidonic acid (SDA, 18 : 4n-3) are considered better precursors of long-chain n-3 PUFA (LC n-3 PUFA) than those with only α-linolenic acid (ALA, 18 : 3n-3). The present study re-examined this premise using treatments where added ALA from linseed oil was matched with ALA plus SDA from echium oil. Lambs (n 6) were abomasally infused with saline (control (C), 25 ml), echium oil low (EL, 25 ml), echium oil high (EH, 50 ml), linseed oil low (LL, 25 ml) or linseed oil high (LH, 50 ml) for 4 weeks. The basal ration used was identical across all treatments. EPA (20 : 5n-3) in meat increased from 6•5 mg in the C lambs to 16•8, 17•7, 13•5 and 11•7 (sem 0•86) mg/100 g muscle in the EL, EH, LL and LH lambs, respectively. For muscle DPA (docosapentaenoic acid; 22 : 5n-3), the corresponding values were 14•3, 22•2, 18•6 18•2 and 19•4 (sem 0•57) mg/100 g muscle. The DHA (22 : 6n-3) content of meat was 5•8 mg/100 g in the C lambs and ranged from 4•53 to 5•46 (sem 0•27) mg/100 g muscle in the oil-infused groups. Total n-3 PUFA content of meat (including ALA and SDA) increased from 39 mg to 119, 129, 121 and 150 (sem 12•3) mg/100 g muscle. We conclude that both oil types were effective in enhancing the EPA and DPA, but not DHA, content of meat. Furthermore, we conclude that, when balanced for precursor n-3 fatty acid supply, differences between linseed oil and echium oil in enriching meat with LC n-3 PUFA were of little, if any, nutritional significance. © 2011 The Authors.


Calnan H.B.,Australian Cooperative Research Center for Sheep Industry Innovation | Calnan H.B.,Murdoch University | Jacob R.H.,Australian Cooperative Research Center for Sheep Industry Innovation | Pethick D.W.,Australian Cooperative Research Center for Sheep Industry Innovation | And 3 more authors.
Meat Science | Year: 2014

Spectrophotometric measures were used to determine the redness:browness (R630/R580) of 4238 lamb longissimus muscle after 3. days under simulated display. The results were analysed using linear mixed effects models. Environmental factors represented by effects such as kill group and site of production produced the greatest variation of up to 2.76 units in R630/R580. Isocitrate dehydrogenase activity, reflecting muscle oxidative capacity, reduced R630/R580 by 0.5 units. Selection for high muscling sires increased R630/R580 by 0.27 units, likely due to changes in muscle oxidative capacity. Lamb carcass weight also increased R630/R580 by 0.5 units. Analysis of genotypic factors influencing lamb size and growth rate such as sire type and dam breed further supported that increased growth rate improves meat R630/R580. Our findings suggest that breeding for increased growth rate and increased muscle weight could result in Australian lamb meat retaining its red colour for extended periods whilst on display. © 2013 The Authors.


Khliji S.,Industry and Investment NSW Primary Industries | Khliji S.,University of Catania | van de Ven R.,Orange Agricultural Institute | Lamb T.A.,Industry and Investment NSW Primary Industries | And 3 more authors.
Meat Science | Year: 2010

Given the lack of data that relates consumer acceptance of lamb colour to instrument measures a study was undertaken to establish the acceptability thresholds for fresh and displayed meat. Consumers (n = 541) were asked to score 20 samples of lamb loin (m. longissimus thoracis et lumborum; LL) on an ordinal scale of 1 (very acceptable) to 5 (very unacceptable). A sample was considered acceptable by a consumer if it scored three or less. Ten samples were used for testing consumer response to fresh colour and 10 to test consumer response to colour during display of up to 4 days. The colour of fresh meat was measured using a Minolta chromameter with a closed cone and a Hunter Lab Miniscan was used for measuring meat on display. For fresh meat when the a* (redness) and L* (lightness) values are equal to or exceed 9.5 and 34, respectively, on average consumers will consider the meat colour acceptable. However a* and L* values must be much higher (14.5 and 44, respectively) to have 95% confidence that a randomly selected consumer will consider a sample acceptable. For aged meat, when the wavelength ratio (630/580 nm) and the a* values are equal to or greater than 3.3 and 14.8, respectively, on average consumers will consider the meat acceptable. These thresholds need to be increased to 6.8 for ratio (630/580 nm) and 21.7 for a* to be 95% confident that a randomly selected consumer will consider a sample acceptable. Crown Copyright © 2010.


Kelman K.R.,Australian Cooperative Research Center for Sheep Industry Innovation | Kelman K.R.,Murdoch University | Pannier L.,Australian Cooperative Research Center for Sheep Industry Innovation | Pannier L.,Murdoch University | And 4 more authors.
Meat Science | Year: 2014

Selection for increased lean meat yield using Australian Sheep Breeding Values for reduced post-weaning c-site fat depth (PFAT) and increased post-weaning eye muscle depth (PEMD) reduces the oxidative capacity of muscle. Isocitrate dehydrogenase (ICDH) activity and myoglobin concentration were measured in 3178 and 5580 lambs, respectively, to indicate oxidative capacity. In the progeny of sires with a reduced PFAT, ICDH activity and myoglobin concentration were reduced by 0.46. μmol/min/g tissue and 0.67. mg/g tissue across the 5 and 6. mm PFAT ranges respectively. In the progeny of sires with an increased PEMD, ICDH activity and myoglobin concentration were reduced by 0.50 μmol/min/g tissue and 0.49. mg/g tissue across the 7 and 6 mm PEMD ranges respectively. However, the sites at which the lambs were raised had a larger impact on oxidative capacity than genetic or other production factors. © 2013 The Authors.


Pannier L.,Australian Cooperative Research Center for Sheep Industry Innovation | Pannier L.,Murdoch University | Pethick D.W.,Australian Cooperative Research Center for Sheep Industry Innovation | Pethick D.W.,Murdoch University | And 7 more authors.
Meat Science | Year: 2014

There is a concern regarding the possible decline of nutritional value of meat with an increasing selection for lean meat yield. The selection for reduced fatness reduces muscle aerobicity and possible subsequent mineral concentrations. Average concentrations of iron and zinc of 5625 lamb longissimus muscles were 2.03 and 2.43. mg/100. g, qualifying as a good source claim for the majority of the population. Reduced post-weaning fat depth was associated with decreased concentrations of iron but not zinc, whereas post-weaning eye muscle depth and weaning weight were not associated with either mineral. These results confirm that the impact of lean meat yield selection on these minerals is minimal, but should be monitored to avoid lower levels. Both minerals had a positive relationship with age at slaughter, highlighting age as a key determinant of the concentration of these nutrients. The magnitude of the positive associations of isocitrate dehydrogenase and myoglobin with iron was larger than for zinc, but they strongly indicated the association of these aerobic makers with both minerals. © 2013 The Authors.


Pannier L.,Australian Cooperative Research Center for Sheep Industry Innovation | Pannier L.,Murdoch University | Pethick D.W.,Australian Cooperative Research Center for Sheep Industry Innovation | Pethick D.W.,Murdoch University | And 7 more authors.
Meat Science | Year: 2014

Selection for lean growth through Australian Sheep Breeding Values (ASBVs) for post weaning weight (PWWT), eye muscle depth (PEMD) and c-site fat depth (PFAT) raises concerns regarding declining intramuscular fat (IMF) levels. Reducing PFAT decreased IMF by 0.84% for Terminal sired lambs. PEMD decreased IMF by 0.18% across all sire types. Female lambs had higher IMF levels and this was unexplained by total carcass fatness. The negative phenotypic association between measures of muscling (shortloin muscle weight, eye muscle area) and IMF, and positive association between fatness and IMF, was consistent with other literature. Hot carcass weight increased IMF by 2.08% between 12 and 40. kg, reflective of development of IMF as lambs approach maturity. Selection objectives with low PFAT sires will reduce IMF, however the lower impact of PEMD and absence of a PWWT effect, will enable continued selection for lean growth without influencing IMF. Alternatively, the negative impact of PFAT could be off-set by inclusion of an IMF ASBV. © 2013 The Authors.


Calnan H.,Australian Cooperative Research Center for Sheep Industry Innovation | Calnan H.,Murdoch University | Jacob R.H.,Australian Cooperative Research Center for Sheep Industry Innovation | Pethick D.W.,Australian Cooperative Research Center for Sheep Industry Innovation | And 3 more authors.
Meat Science | Year: 2016

M. longissimus colour was measured from 8165 lambs at 24 h post-mortem using a chromameter. The impact of production factors (site and year of production, slaughter group, sex, age and breed type) and muscle traits (hot carcass weight, pH24, isocitrate dehydrogenase (ICDH) activity, myoglobin, iron and zinc concentrations) on meat lightness (L*), redness (a*), yellowness (b*), hue and chroma were analysed. Greater differences in meat colour were seen between different slaughter groups and sites of production than across the range of any muscle traits. Of the muscle traits analysed, changes in pH24 had the greatest effect on meat a* (2.5 units), while myoglobin had the greatest effect on meat L* (2.9 units). The 3.1 L* unit darkening of meat with increasing lamb age (from 140 to 400 days) was accounted for by increased myoglobin concentration. These results suggest that production factors are having substantial effects on lamb colour independent of known influencing muscle traits such as myoglobin concentration and pH. © 2016 Elsevier Ltd.


PubMed | Australian Cooperative Research Center for Sheep Industry Innovation
Type: Controlled Clinical Trial | Journal: The British journal of nutrition | Year: 2012

Vegetable oils containing stearidonic acid (SDA, 18 : 4n-3) are considered better precursors of long-chain n-3 PUFA (LC n-3 PUFA) than those with only -linolenic acid (ALA, 18 : 3n-3). The present study re-examined this premise using treatments where added ALA from linseed oil was matched with ALA plus SDA from echium oil. Lambs (n 6) were abomasally infused with saline (control (C), 25 ml), echium oil low (EL, 25 ml), echium oil high (EH, 50 ml), linseed oil low (LL, 25 ml) or linseed oil high (LH, 50 ml) for 4 weeks. The basal ration used was identical across all treatments. EPA (20 : 5n-3) in meat increased from 65 mg in the C lambs to 168, 177, 135 and 117 (SEM 086) mg/100 g muscle in the EL, EH, LL and LH lambs, respectively. For muscle DPA (docosapentaenoic acid; 22 : 5n-3), the corresponding values were 143, 222, 186 182 and 194 (SEM 057) mg/100 g muscle. The DHA (22 : 6n-3) content of meat was 58 mg/100 g in the C lambs and ranged from 453 to 546 (SEM 027) mg/100 g muscle in the oil-infused groups. Total n-3 PUFA content of meat (including ALA and SDA) increased from 39 mg to 119, 129, 121 and 150 (SEM 123) mg/100 g muscle. We conclude that both oil types were effective in enhancing the EPA and DPA, but not DHA, content of meat. Furthermore, we conclude that, when balanced for precursor n-3 fatty acid supply, differences between linseed oil and echium oil in enriching meat with LC n-3 PUFA were of little, if any, nutritional significance.

Loading Australian Cooperative Research Center for Sheep Industry Innovation collaborators
Loading Australian Cooperative Research Center for Sheep Industry Innovation collaborators