alpine grasslands: relations among botanical and chemical...

Alpine grasslands: relations among botanical and chemical

variables affecting animal product quality

M. Renna, S. Ravetto Enri, M. Probo, C. Lussiana, V. Malfatto, L.M. Battaglini, M. Lonati, G. Lombardi

Department of Agricultural, Forest and Food Sciences, Torino University, Italy

19th Meeting of the FAO‐CIHEAM Mountain Pastures sub‐network 14-16 June 2016

Effect of different grassland communities and ecological groups on herbage chemical composition still largely unknown

Introduction

Renna et al. “Alpine grasslands: relations among botanical and chemical variables affecting animal product quality”. 19th Meeting of the FAO‐CIHEAM Mountain Pastures sub‐network, Zaragoza (Spain), 14th-16th June, 2016.

Forage composition

key factor for product quality

Extensive farming systems complex and species-rich semi-natural grasslands

To assess the relationships between vegetation characteristics and chemical composition in different species-rich alpine grasslands

AIM

Materials and methods


Experimental

Piedmont (NW Italy), 250 to 2000 m a.s.l.

chemical composition

dry matter

crude protein

fatty acids

fiber fractions

vegetation characteristics

botanical composition phenological stage

Landolt’s ecological indicators biodiversity

pastoral value

39 vegetation surveys

Results and Discussion

Correlation Analysis


DM

CP

NDF

ADF

C16:0 C18:0

C18:1 n9

C18:2 n6

C18:3 n3

TFA

C16:0 (-0.65***), C18:1n9 (0.57***), C18:2n6 (-0.43**), C18:3n3 (-0.79***), TFA (-0.71***), PV (-0.40*), Phenology (0.33*), Poaceae (0.34*)

C16:0 (0.81***), C18:1n9 (-0.46**), C18:2n6 (0.45**), C18:3n3 (0.79***), TFA (0.76***), Phenology (-0.33*)

C16:0 (-0.81***), C18:2n6 (-0.48**), C18:3n3 (-0.81***), TFA (-0.82***), PV (-0.35*), Fabaceae (-0.54***), Poaceae (0.36*)

C16:0 (-0.69***), C18:1n9 (0.55***), C18:2n6 (-0.35*), C18:3 n3 (-0.78***), TFA (-0.70***), PV (-0.46**), Fabaceae (-0.38*)

C18:0 (0.38*), C18:2n6 (0.75***), C18:3n3 (0.79***), TFA (0.90***), PV (0.34*)

C18:1n9 (0.60***), C18:2n6 (0.44**)

C18:3n3 (-0.41**), Phenology (0.40*)

C18:3n3 (0.56***), TFA (0.77***), Poaceae (-0.36*)

TFA (0.95***), PV (0.36*), Fabaceae (0.42**), Poaceae (-0.34*)

Fabaceae (0.36*), Poaceae (-0.37*)



Hierarchical Cluster Analysis

Dominant species

Grassland types

Ecological groups

Mesophilic grasslands

Dry grasslands



Canonical Correspondence Analysis

Mesophilic

grasslands

Dry

grasslands

53.1% total

variance explained


Canonical Correspondence Analysis




Indipendent Samples Student’s t-Tests

g/100 g DM

Mesophilic grasslands

Dry grasslands SEM P

DM, g/100 g 22.3 38.1 70% 1.68 *** CP 13.6 10.2 25% 0.45 *** NDF 48.9 56.3 15% 1.19 *** ADF 29.5 36.6 24% 0.86 *** C16:0 0.33 0.27 18% 0.01 *** C18:1n9 0.07 0.12 71% 0.00 ** C18:2n6 0.34 0.28 18% 0.01 * C18:3n3 0.98 0.60 39% 0.06 *** Total FA 1.88 1.41 25% 0.08 ** Pastoral Value 40.0 27.9 30% 2.01 ** Landolt’s F 2.6 2.2 15% 0.05 *** Landolt’s N 3.3 2.6 21% 0.08 *** Landolt’s R 3.0 3.5 17% 0.05 ***

Conclusions


1. The proximate composition and fatty acid profile of alpine grasslands are significantly influenced by the botanical composition of the vegetation

2. The abundance of single plant species affected the chemical composition of forages more than the abundance of botanical families

3. If compared to dry grasslands, mesophilic grasslands showed:

- higher relative abundance of productive and palatable plant species

- higher pastoral values

- higher contents of crude protein and lower values of fiber

- higher contents of lipid precursors for the synthesis of beneficial FA in dairy and meat products

Thank you for your attention

alpine grasslands: relations among botanical and chemical...

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