Summer transhumance is often practiced in mountainous farming systems. It includes moving dairy cows from lowland (LO) to highland (HI) pastures during summer. It is known that high genetic merit cows are susceptible to the HI conditions, but it is unclear if this also applies to more adapted, regional cow types. The present study aimed to investigate the effect of HI sojourn on cheese-making properties of Aosta Red Pied cows, a dual purpose cattle type. Milk coagulation properties were measured in the milk of 47 cows before and after transhumance. Sources of variation were investigated using linear mixed models, including parity, site, milking time, the interaction parity  site, milking time  site and milking time  parity. Cow was nested within site, and used as subject for repetition, and sampling date was included as repeated factor. Curd-firming time and curd firmness did not vary between LO and HI, whereas rennet coagulation time was prolonged in HI compared to LO in both primiparous (16.4 vs. 18.5 min) and multiparous cows (17.5 vs. 21.1 min, respectively). The percentage of non-coagulating samples was greater in HI (15.0%) compared to LO (8.5%). The lower milk reactivity to rennet addition in HI seems to be mostly related to the simultaneously increasing somatic cell score. Morning and evening milk were similar in coagulation properties. In conclusion, even indigenous dual purpose cows were affected by HI conditions and the experience the multiparous cows had with the transhumance was not helpful either. ARTICLE HISTORY

This study was designed to evaluate the effects of two feeding methods on milk yield, composition and fatty acid (FA) profile obtained from dual-purpose cattle. Twenty-four Aosta Red Pied cows beyond peak of lactation were assigned to two groups and fed hay and concentrates in the proportions 0.69 and 0.31 on a dry matter basis for 10 weeks. Concentrates were offered separately from forages 6 times a day (separate ration, SR) or as a total mixed ration (TMR). The feeding method did not significantly influence dry matter intake (16.8 vs. 16.9 kg/head/day for SR- and TMR-fed cows, respectively), milk yield (17.4 vs. 17.5 kg/head/day), milk fat, protein and lactose contents (36.4 vs. 35.2, 33.5 vs. 32.8, and 47.3 vs. 47.4 g/kg) and yields (607.9 vs. 613.4, 567.4 vs. 572.7 and 805.5 vs. 829.7 g/head/day). The overall milk FA profile was very similar between groups. Milk concentrations of FA used as indirect markers of rumen function (C18:2 t10c12, odd- and branched-chain FA) and the extent of ruminal biohydrogenation were comparable (P > 0.05) between SR- and TMR-fed cows, suggesting that ruminal pH did not vary considerably as a consequence of the feeding strategy applied.

Hazelnut skin (HS) was evaluated as a source of nutrients for dairy cows. In total, 26 Aosta Red Pied cows were divided into two balanced groups. All cows were fed hay ad libitum. The control group was also given 6 kg of concentrate, while the hazelnut skin group (HAZ) was given 1 kg of the same concentrate that was substituted by 1 kg of HS. The dry matter intake of the cows was reduced by the dietary inclusion of HS (p ≤ 0.001). The milk yield and main constituents were unaffected by treatment. Milk from HAZ cows showed decreased concentrations of de novo saturated fatty acids (FAs), odd- and branched-chain FA, α-linolenic acid, and long-chain n-3 FAs, as well as increased concentrations of stearic acid, oleic acid, linoleic acid, total monounsaturated FAs, trans biohydrogenation intermediates, and α–tocopherol. Replacing the concentrate with HS increased the human-inedible feed quota in the diet and improved the sustainability of milk production in terms of the food-feed competition. Our results suggest that it is possible to add economic value to organic waste from the hazelnut industry using HS as a feed ingredient for dairy cows, enhancing the feed efficiency and milk antioxidant activity and having expected impacts on the nutraceutical quality of milk fat.

The aim of this study was to determine how cows with different genetic merit behave and perform when grazing biodiverse and heterogeneous mountain pastures with different slopes. Three groups of 12 cows in late lactation, each composed of four Holstein, four Montbéliarde and four Valdostana Red Pied cows, breeds of increasing presumed robustness and decreasing milk yield (MY) potential. Cows grazed without concentrate either on a low-diversity flat pasture or on two species-rich mountainous pastures having slopes of either 7° or 22°. Milk yield, BW and grazing behaviour were monitored two times in the first and once in the second grazing cycle. Cows of different breeds had similar behaviour on all pastures. The Montbéliarde cows performed close to their production potential; Holstein and Valdostana cows produced less milk than anticipated. No breed difference in terms of BW loss was found. The Valdostana cows exhibited the least selective behaviour with respect to plant species and plant growth stage. Still, all cows searched for the most palatable vegetation regardless of pasture diversity. On the steep pasture, cows optimised the trade-off between ingesting and saving energy to obtain feed. They remained longer at the lowest zone and selected forbs, whereas cows on the flatter pasture went to the upper zone to select grasses. The present study gave no evidence for a superior short-term adaptation to harsh grazing conditions through an optimised feeding behaviour of the Valdostana breed compared to Montbéliarde and Holstein cows.

This Research Communication describes the effects of a synthetic analogue of the Bovine Appeasing Pheromone (BAP) on milk parameters in Valdostana dairy cows during the first turning out from tie-stalls to confined lowland pastures around the farms. Thirty healthy lactating Valdostana cows were enroled in the study and randomly divided into 2 groups: experimental group (EG, n = 15) and control group (CG, n = 15). The two groups were separately housed in the same farm and managed outside in two different pens. Treatment (BAP and solution) and control (solution only) were poured on the nuchal skin area between the horns when the animals were inside the farm at the feeding rack every 7 d for 28 d (T0-T4). Milk samples were evaluated at the same time points (T0-T4). Daily milk production (kg/day) was higher in the EG than in the CG, particularly during the first day after the turning out to pasture (T1). Somatic Cell Count (103 cells/ml) was higher in the placebo group than in the EG, especially at T1. Proteins, fat, fat-free dry matter and casein (g/100 g) were not affected by the treatment. In T1 urea (mg/dl) content was higher in CG vs. EG, suggesting a more correct metabolic balance in the group treated with BAP. The use of BAP appears to modulate adaptation in ways that may improve dairy cow performance in the context of changes in management routines.