Effects of grazing conditions on alpine pastures on muscle growth, meat quality and fatty acid profile

Seasonal alpine pastures are an essential part of the traditional mountain dairy production in Switzerland, and they also arouse interest for extensive beef production. The characteristic pedoclimatical conditions on seasonal alpine pastures generate unique features in dairy products, which could also be expected in meat produced under these conditions. However, knowledge about performances and meat quality of beef cattle on alpine pastures is lacking. In the present project, the separate effects of the vegetation on seasonal alpine pastures on the one hand, and of their characteristic topography on the other hand, were studied in comparison with typical conditions of lowland grass fattening. The latter was represented by a cultivated lay to study the effect of vegetation or by a flat terrain to study the effect of topography, respectively. The effects of the alpine vegetation were tested on beef heifers whereas the effects of the alpine topography were tested on suckling beef calves. As a finishing period is often practiced by commercial farms after a stay on seasonal alpine pastures, the effect of a finishing period in barn was tested following the period where the effects of the alpine vegetation had been investigated. Additionally, different beef calf systems (suckling, weaned and mentored by experienced adults, or weaned and kept among themselves) on alpine pastures were compared. If growth performance was not affected by the native alpine vegetation, in comparison with performances obtained from a cultivated lay in the lowland, meat colour was found to be less yellow and less red with the alpine vegetation, and some of the expected fatty acid characteristics found in dairy products were retrieved in the meat. Finishing positively influenced growth performance due to the compensatory growth of the animals, but no effect of the alpine vegetation could be maintained concerning meat quality characteristics, including the effect on the fatty acid profile. Physical activity, as influenced by the characteristic inclination on seasonal alpine pastures, had limited consequences on growth performances and positively influenced meat quality of suckling beef calves. Meat brightness, juiciness and tenderness were higher in beef calves kept on pastures with a high inclination, with a muscle-dependent response. Muscle contractile metabolism differed according to the topography of the pasture. However, the post mortem proteolytic metabolism was limitedly and inconsistently affected by physical activity. In the system comparison, suckling calves had a reduced physical activity and a better growth performance than weaned calves. Among weaned calves, the mentored calves showed more physical activity but similar growth performances compared with calves kept 12 among themselves. This suggests a positive effect of the presence of mentoring adults. Differences in physical activity were not retrieved in meat quality due to large slaughter weight differences. The present results showed that both the alpine vegetation and the alpine topography influenced meat quality but that a poor growth or a finishing period in barn could also counteract these effects. In the present experiments, satisfactory slaughter performances and meat quality were obtained also without finishing. The key factor to obtain animals ready to slaughter at the end of their stay on seasonal alpine pastures seems to be the balance between the quality of the diet available and the growth stage of the animals

Response of dual-purpose and layer hybrid hens in yield and quality of eggs, carcass and meat to a diet composed of food industry by-products and grain legumes: a pilot study

In common layer hybrid nutrition, feedstuffs potentially human edible and soybean-based feeds cover most of the diet. The use of alternative energy and protein sources is limited due to insufficient nutrient density. We investigated whether less demanding dual-purpose poultry would better tolerate a diet composed of food industry by-products and grain legumes. Hen types investigated were Lohmann Brown Plus (LB, layer hybrid; n = 10), Lohmann Dual (LD, a dual-purpose hybrid; n = 10), Belgian Malines (BM) and Schweizerhuhn (CH) (both traditional dual-purpose breeds; n = 9). Hens were in late stage of lay. In a cross-over design, hens received for 4 weeks a common layer diet (C; 11.5 MJ/kg N-corrected metabolizable energy (ME) and 4.3 g methionine/kg) or a diet exclusively composed of by-products and grain legumes (B; 10.4 MJ/kg ME and 2.4 g methionine/kg). Subsequently they stayed for another 8 weeks on the respectively other diet until slaughter. Feed efficiency (g feed/g egg) was better in LB (2.7) and LD (2.8) than CH (4.6) and BM (5.2). Body and carcass weights (kg) were highest in BM (3.4/2.0), followed by CH (2.6/1.6), and lowest in LB and LD (both 1.9/1.1). Feed efficiency was higher in diet C than B, as was egg weight (g; C: 63; B: 59). Diet B adversely affected carcass weight, breast meat yield and meat shear force, but not egg quality. Feed intake (g/day) declined in LB from 121 to 65 and in LD from 102 to 80 when switching from diet C to B. With diet B, laying performance declined from 92 to 53% in LB and from 70 to 50% in LD. Both traits remained unaffected in BM and CH, showing that diet B was sufficient only in these two hen types in late laying. Further studies have to confirm these results with more replicates and different by-product diets

Carcass and meat quality of finished and non-finished Limousin heifers from alpine livestock systems differing in altitudinal origin of the forage

Effects of the alpine origin of the forage and of finishing on carcass and beef quality were quantified by modelling different alpine livestock system alternatives. Thirty-five Limousin heifers, initially weighing 383 ± 45 kg, were fed fresh grass at 400 or 2000 m above sea level, or a 1:1 mixture of alpine grass and lowland grass hay at 2000 m. After 9 weeks, the six heaviest and oldest animals per group were slaughtered. The remaining animals were finished for 8 weeks on a silage-concentrate diet in the lowlands to similar age and body weight as the first slaughtered group. Carcass and meat quality (M. longissimus thoracis) were assessed in various respects. The average daily gains achieved were of about 600 g/d and similar between forage-type groups. Dressing percentage was 53.5% in the alpine and 57.2% in the lowland group. Carcass conformation and fat cover scores did not differ between forage-type groups. The meat from the alpine groups had greater ultimate pH and smaller redness, yellowness and protein contents. Still, these differences were of minor practical relevance. There was no forage-type effect on water-holding capacity and shear force of the meat. The alpine systems enhanced the proportion of α-linolenic acid in intramuscular fat and decreased the levels of some volatile compounds in perirenal fat. Finishing resulted in compensatory growth, especially in the animals previously fed lowland grass. There was a trend for the finished compared with the non-finished groups towards greater carcass fat cover and intramuscular fat content. Additionally, ultimate pH was smaller and cooking loss was greater with than without finishing. Meat colour differences were also observed. Shear force was not affected by finishing. The finished animals had a smaller α-linolenic acid proportion in the intramuscular fat. In conclusion, the forage type had small effects on carcass and meat quality. Finishing did not substantially improve carcass and meat quality. The (alpine) grass-specific differences in fatty acid profile found in the unfinished cattle were not present in the finished animals

Carcass and meat quality of dual-purpose chickens (Lohmann Dual, Belgian Malines, Schweizerhuhn) in comparison to broiler and layer chicken types

Currently, there is an intensive ethical discussion about the practice of culling day-old layer cockerels. One solution to avoid this practice could be using dual-purpose types, where males are fattened for meat and females used for egg production. The aim of the present study was to compare fattening performance, carcass conformation, and composition as well as meat quality of Lohmann Dual, a novel dual-purpose type, and 2 traditional dual-purpose types (Belgian Malines and Schweizerhuhn) with 2 broiler types and 1 layer type (Lohmann Brown Plus). Broilers included a conventional line (Ross PM3) and a slower-growing line (Sasso 51) fulfilling requirements of organic farming. Nine birds of each type were fed on a conventional broiler diet. Feed intake and metabolizability of nitrogen and energy were recorded per pen (n = 3), the latter through excreta sampling. For each bird, carcass conformation was assessed, and weights of body, carcass, breast meat, legs, wings, and inner organs were determined. Additionally, breast angle, an indicator for carcass appeal, and skin color were recorded. Meat quality assessment included determinations of thaw and cooking loss, shear force, meat color, and proximate composition of the breast meat. None of the dualpurpose types (20 to 30 g ADG) performed as well in growth as the intensively growing broiler line (68 g ADG). However, Lohmann Dual could compete with the slower-growing broiler line (slower growth but better feed efficiency, similar in carcass weight and breast proportion). Also breast angle was quite similar between Lohmann Dual (100◦) and the extensive broiler type (115◦C) compared to the intensive broiler line (180◦). Meat quality was most favorable in the intensive broilers with the smallest shear force and thawing loss, whereas meat quality was not different between the other types. The Schweizerhuhn performed only at the level of the layer hybrid, and the Belgian Malines was ranked only lightly better

Effect of nursing or mentoring by adult cows on physical activity, performance and meat quality of fattening beef calves kept on alpine pastures

BACKGROUND: Compared with weaned calves, nursed calves benefit from access to milk as nutrient-dense feed andmentoring by their dams. Bothmay be decisive for growth under difficult conditions such as grazing on alpine pastures, where experience could play an essential role. These factors were investigated separately by comparing nursed calves with calves weaned at 3 months of age and grazing with or without amentor cow (n = 8 calves). RESULTS: Weaned calves with mentor cows spent less time lying and walked more than nursed calves. Irrespective of whether they had a mentor cow or not, the weaned calves grew slower than the nursed calves (357, 428 and 1324 g day−1 respectively). This also adversely affected slaughter weight, dressing percentage, conformation and fat cover at slaughter. In general, mentoring had no effect. Meat quality did not differ whetherweaned calveswere mentored or not. Nursed calveswere superior in intramuscular fat content, tenderness and water-holding capacity. CONCLUSION: The availability ofmilk appeared to be muchmore important to the calves under demanding grazing conditions than did mentoring. The differences in growth rate were accompanied by unexpectedly large differences in meat quality, showing that early weaning was not suitable for this system