Norwegian Lambs Research Articles

Carcass Characteristics, Physicochemical and Sensory Meat Quality of Norwegian Lambs Finish-Fed on Forage Rape

Effects of finishing Norwegian lambs of grazing forage rape on carcass and meat quality were studied. A total of 59 Norwegian short tail lambs (126 days old, 36.15 kg BWT) were randomly allotted to three groups. T1 group lambs grazed on grass pasture for three weeks before slaughter; T2 group grazed on grass and forage rape for two weeks and then withdrawn to grass only for one week. T3 group was maintained on grass and forage rape grazing for three weeks before slaughter. Carcasses from T2 lambs had lower (P < 0.05) conformation scores than T1, which was comparable to T3. Meat from lambs grazed on forage rape had higher (P < 0.05) content of n-3 PUFA but lower n-6:n-3 PUFA ratio than ones grazed on grass. Meat from T3 lambs had higher (P < 0.05) sweet odour and cloy taste than T1 lambs. It is concluded that lighter Norwegian lambs after mountain grazing can be finished by feeding on forage rape for three weeks without the risk of producing unacceptable flavour.

Treatment against coccidiosis in Norwegian lambs and potential risk factors for development of anticoccidial resistance\u2014a questionnaire-based study

The objectives of this study were to investigate the use of anticoccidials in Norwegian sheep flocks and identify farms with management procedures likely to select for drug resistance. Data were obtained by a questionnaire sent to all members of the Norwegian Sheep Recording System in October 2015. The data set consisted of 1215 answers, corresponding to 8.5% of Norwegian sheep flocks. Anticoccidials were used in 82.7% of flocks. Main treatment was at turnout (38.6% of treated flocks) or 1 week after turnout (32.4%). Interestingly, clinical signs possibly related to coccidiosis were observed by almost 40% of the farmers after treatment, which might be an indication of drug resistance. Correlations between the apparently reduced anticoccidial efficacy and management conditions, such as the size of the farms, were found. From the farmers’ perspective, metaphylactic treatment was used in 88.5% of treated flocks, of which approximately one third had no history of clinical coccidiosis. Even though farmers seem aware of the importance of good drenching routines based on reliable estimates of weights and calibration of drench guns, drench gun used for anticoccidial administration was never calibrated in 12.1% of the flocks. Finally, dose estimation was made by visual appraisal in 27.5% of the flocks, which can lead to incorrect dosing. Based on the present study, it cannot be determined whether the apparent treatment failure was related to management practises, incorrect administration of the drug, other infections or actual anticoccidial drug resistance.

Mobile abattoir versus conventional slaughterhouse—Impact on stress parameters and meat quality characteristics in Norwegian lambs

The aim of the present study was to investigate possible differences in certain stress parameters and meat quality characteristics between Norwegian lambs slaughtered at a mobile abattoir (at two different localities) versus lambs slaughtered at a conventional, stationary slaughterhouse. Lambs slaughtered at the conventional slaughterhouse had higher serum cortisol levels than lambs slaughtered at a mobile abattoir (P<0.001). Also blood glucose values were significantly lower at one of the two mobile slaughter localities compared to the stationary abattoir (P<0.001). Animals at the conventional slaughterhouse displayed a higher frequency of vocalizations (P<0.01) and showed more aggressive behaviour than lambs at the mobile slaughterhouse (P<0.01). It was demonstrated that meat from lambs slaughtered at the mobile slaughterhouse had lower ultimate pH (P<0.001). Also, meat from one of the mobile slaughter locations was more tender (having a lower Warner Bratzler shear force value, WB), compared to meat from the lambs slaughtered at the conventional abattoir (P<0.05). Furthermore, some relationships between stress indicators and meat quality were demonstrated. WB was positively correlated to serum cortisol level (r=0.39, P<0.05). There was a positive correlation between serum cortisol level and the incidence of aggressive interactions (r=0.47, P<0.05). The frequency of aggressive interactions was positively correlated to number of vocalizations (r=0.73, P<0.01) and also muscle pH (r=0.66, P<0.05). Finally, the frequency of aggressive behaviours was negatively correlated to blood glucose levels (r=0.46, P<0.05).

Meat Science; 2nd Edition: An Introductory Text, Paul D. Warriss. CABI Publishers, Wallingford, UK (2010), Viii +234 pp., £35.00, ISBN: 978-1-84593-593-1

The aim of the present study was to investigate possible differences in certain stress parameters and meat quality characteristics between Norwegian lambs slaughtered at a mobile abattoir (at two different localities) versus lambs slaughtered at a conventional, stationary slaughterhouse. Lambs slaughtered at the conventional slaughterhouse had higher serum cortisol levels than lambs slaughtered at a mobile abattoir (P < 0.001). Also blood glucose values were significantly lower at one of the two mobile slaughter localities compared to the stationary abattoir (P < 0.001). Animals at the conventional slaughterhouse displayed a higher frequency of vocalizations (P < 0.01) and showed more aggressive behaviour than lambs at the mobile slaughterhouse (P < 0.01). It was demonstrated that meat from lambs slaughtered at the mobile slaughterhouse had lower ultimate pH (P < 0.001). Also, meat from one of the mobile slaughter locations was more tender (having a lower Warner Bratzler shear force value, WB), compared to meat from the lambs slaughtered at the conventional abattoir (P < 0.05). Furthermore, some relationships between stress indicators and meat quality were demonstrated. WB was positively correlated to serum cortisol level (r = 0.39, P < 0.05). There was a positive correlation between serum cortisol level and the incidence of aggressive interactions (r = 0.47, P < 0.05). The frequency of aggressive interactions was positively correlated to number of vocalizations (r = 0.73, P < 0.01) and also muscle pH (r = 0.66, P < 0.05). Finally, the frequency of aggressive behaviours was negatively correlated to blood glucose levels (r = 0.46, P < 0.05).

Prediction of fat, muscle and value in Norwegian lamb carcasses using EUROP classification, carcass shape and length measurements, visible light reflectance and computer tomography (CT)

One hundred and twenty carcasses were sampled to compare different techniques or methods for prediction of lamb carcass composition and value. Four methods that are used at the Norwegian Meat Research Centre, Animalia, were selected. These were the basic EUROP classification, the advanced EUROP classification using carcass shape and length measurements, visible light reflectance probing (GP) and Computer Tomography (CT). The different technologies were tested using an iterative approach, selecting calibration and validation data sets from the 120 carcasses randomly, where 90 carcasses were used for calibration, and 30 for validation. The best prediction models were obtained using CT, with respect to prediction error and correlation between predicted and measured value of carcass fat and muscle (in kg), and value (in NOK). Due to high cost and low operating speeds of CT, optical probing (GP) may be the second best solution of the technologies used in this study, combined with a CT dissection reference as an alternative to manual dissection.

Suitability of Norwegian short-tail lambs, Norwegian dairy goats and Cashmere goats for meat production – Carcass, meat, chemical and sensory characteristics

Six female Norwegian lambs (29 kg body weight, 8 months old), six castrated Norwegian goats (27 kg body weight, 10 months old) and six castrated Cashmere goats (20 kg body weight, 8 months old) were used to study the relative potential of Norwegian lambs, Norwegian goats and Cashmere goats for meat production. Animals were fattened on silage and commercial concentrate before slaughter. Lamb meat had 4 % lower ( P < 0.05) proteins and 13% higher ( P < 0.05) fat content than goat meats. Moreover, m. longissimus dorsi samples from lambs were less red ( a ∗) ( P < 0.05) and had lower colour intensity ( C) and wider hue angle ( H) than that from goats. Meat from lambs and Cashmere goats had higher proportions of saturated fatty acids (SFA) ( P < 0.001), especially stearic acid and lower ones for total unsaturated fatty acids (TUFA) and monounsaturated fatty acids (MUFA) than the meat from Norwegian goats. Sensory panellists scored lamb meat fattier, juicier and more tender than goat meats. Meat from Cashmere goats scored highest ( P < 0.05) in whiteness, and lowest ( P < 0.05) in both colour tone and colour intensity. It is concluded that, since C18:0 was the main contributor of SFA in meat from Norwegian lamb and Cashmere goats, meats from them are nutritionally comparable to that from Norwegian goats. However, the higher proportion of SFA in Norwegian lambs and Cashmere goats may increase hardness of fat and being easily solidified upon cooling, may influence meat palatability.

Effect of animal sex and time of slaughter on sensory quality of meat from Norwegian lamb

Using 231 lambs, the effect of animal sex and time of slaughter on sensory quality of meat from Norwegian lamb was investigated. Three experiments were carried out to include common feeding systems and seasonal variation in slaughter for Norwegian lamb. The first experiment was conducted in September 2001 using 40 lambs subjected to grazing on the mountain ranges or cultivated lowland pastures. A follow up experiment was conducted during March and April 2002 using 107 lambs fed indoors by farmers. The third experiment was conducted during October and November 2003 using 84 lambs subjected to either ad libitum or restricted concentrate supplementation under stall-feeding. Except for the March/April experiment, meat from ewe lambs had sour odour scores comparable (P>0.05) to that of ram lambs. On the other hand, meat from ram lambs had higher (P<0.05) scores for sour taste than that of ram lambs irrespective of time of slaughter. Further, in all but March/April slaughter time, meat from ewe lambs were comparable (P>0.05) to that of ram lambs in metallic taste. Whereas meat from ewe lambs slaughtered in September had ram taste comparable to that of ewe lambs, meat from ewe lambs slaughtered in March/April and October/November had 1.2 units and 0.6 units lower (P<0.05) ram taste, respectively, than that from ram lambs. It is concluded that to avoid off-flavour in Norwegian lamb, ram lambs should be slaughtered no later than September and hence consumer demand for fresh lamb in winter, spring and summer should preferentially be met by marketing ewe lambs.

Effects of concentrate feeding systems, genotype and sex on productive performance and meat quality of Norwegian lambs

Two factorial experiments, I and II, were carried out in this study using 84 lambs (140±1.24 days old, 40.00±0.75 kg live weight) divided into six groups. Two levels of concentrate supplementation; restricted (0.4 kg concentrate/lamb/day) or ad libitum, two breed types; Norwegian White lamb or Nor-X and two sex types; ram or ewe lambs, were investigated. In experiment I, a 2×2×2 factorial arrangement of treatments (level of supplementation, sex, and breed) was imposed whereas a 2×2 arrangement of treatments (level of supplementation and breeds) was studied in Experiment II. Each of the two experiments lasted for four weeks. Lambs on ad libitum access to concentrate grew at 231 g d–1 and 125 g d–1 faster than those on restricted access in Experiment I and II, respectively. Moreover, ram lambs grew at 64 g d–1 faster than ewe lambs. Lambs on ad libitum access to concentrate had about 5 kg heavier carcasses than that on restricted access. Ewe and ram lambs on ad libitum allowance to concentrate had 4.2 kg and 5.6 kg, respectively, higher carcass weight than those on restricted allowance. The two levels of concentrate supplementation had limited effects on the meat sensory qualities. Meat taste intensity increased with level of concentrate supplementation. Difference in meat tenderness between ram and ewe lambs was only evidenced on ad libitum concentrate feeding. Irrespective of stage of growth (Experiment I vs. II) and concentrate supplementation level, Nor-X lambs were superior to Norwegian White lambs with respect to carcass conformation scores. Based on results from sensory assessments of meat, ram lambs should be slaughtered before October to avoid off-flavour on meat.

Sapogenin Levels in Narthecium ossifragum Plants and Ovis aries Lamb Faeces during Two Alveld Outbreaks in Møre og Romsdal, Norway, 2001

The proposal that saponins produced by the lily bog asphodel (Narthecium ossifragum) may be the direct cause of the hepatogenous photosensitization disease alveld seen in Norwegian lambs was investigated by comparing sapogenin levels in two control and two toxic pastures, and in faeces from lambs grazing the four pastures in the Halsa and Surnadal municipalities, Møre og Romsdal county, Norway. Generally similar levels of sapogenins, determined after hydrolysis of parent plant saponins, were found in Narthecium leaves collected in June/July 2001 from the two alveld outbreak areas and two nearby control areas. Differences in the median sapogenin levels determined for leaf samples in outbreak and control areas were not statistically significant. The total level of free and conjugated sapogenins in faeces recovered from the rectums of lambs grazing the outbreak and control pastures areas varied greatly. The results obtained do not support the hypothesis that a dose-response relationship exists between Narthecium saponin levels and the occurrence of alveld outbreaks.

Abomasal bloat, haemorrhage and ulcers in young Norwegian lambs

An abomasal syndrome affecting mainly three- to four-week-old lambs was studied by using a case-control design involving 88 cases and 85 controls. The principal clinical signs were tympany and colic....

Fungi on Narthecium ossifragum leaves and their possible involvement in alveld disease of Norwegian lambs.

Spores of Pithomyces chartarum (Berk. & Curt.) M.B. Ellis were only rarely seen on leaves of Narthecium ossifragum (L.) Hudson collected in summer from five areas in western Norway in which alveld, a photosensitization disease of lambs, is endemic. Cladosporium magnusianum (Jaap) M.B. Ellis was found on all 118 leaf samples collected in the summers of 1990 and 1991. The hypothesis that P. chartarum contributes to the aetiology of alveld could not be supported, but it is possible that C. magnusianum may have a role in the causation of the disease.

Failure to induce toxicity in lambs by administering saponins from Narthecium ossifragum

It has been suggested that saponins produced by Narthecium ossifragum (Bog asphodel) may be the direct cause of the toxicity leading to the hepatogenous photosensitivity disease alveld seen in Norwegian lambs. Lambs fed large quantities of freeze-dried N. ossifragum did not develop alveld. Chemical investigations on the freeze-dried material and fresh N. ossifragum showed no difference in their saponin content. These results indicate that alveld is not caused solely by the saponins produced by N. ossifragum.

Differentiation of Eimeria Species Infecting Sheep During the Grazing Season on Permanent and New Pastures Under Norwegian Conditions

The total and differential oocyst counts of the different Eimeria species in the faeces of Norwegian ewes and lambs were investigated at weekly intervals during the grazing period on permanent and new pastures. The total oocyst counts of lambs on permanent pastures were significantly higher than those on new pastures 3–6 weeks after the beginning of the grazing period. This demonstrates that the oocysts had survived the winter in the pasture. Species differentiation indicated that E. ahsata, E. arlongi, E. crandallis, E. ninakohlyakimovae, E. faurei and E. parva are able to survive the winter in the pasture. E. crandallis occurred in the greatest numbers, and this species might be an important contributor to the clinical symptoms which are frequently observed in Norwegian lambs about 2–3 weeks after the beginning of the grazing period. There were on the other hand, indications that E. pallida has little ability to survive the winter in the pasture. The results were generally similar for most of the species during 2 successive years. The total number of oocysts in the faeces of ewes was low on new as well as on permanent pastures, and the species differentiation showed negligible differences. Consequently, it was concluded that the ewes could not be the source of the high oocyst numbers in lambs on the permanent pastures.

Levels of Cs137 in Norwegian Lamb and Sheep 1964-1965

The concentrations of Gs137 in meat from lamb in the falls of 1964 and 1965 and in meat from sheep in the fall of 1965 have been determined. The results are given and discussed with regard to the geographical variations, the decreasing concentrations from 1964 to 1965 and to the different concentrations in lamb and sheep.