Energy and protein Energy and protein allowancesallowances

in diets for athletic horses in diets for athletic horses used in western ridingused in western riding

Department of Animal ScienceDepartment of Animal ScienceUniversity of PadovaUniversity of Padova

e-mail: e-mail: alessandra.brigando@yahoo.italessandra.brigando@yahoo.it

10° Convegno10° ConvegnoNuove acquisizioni in materia di IppologiaNuove acquisizioni in materia di Ippologia

New findings in equine practiceNew findings in equine practiceDruento (Torino), 31 ottobre -1 novembre 2008Druento (Torino), 31 ottobre -1 novembre 2008

A. Brigando, R. Mantovani, L. BailoniA. Brigando, R. Mantovani, L. Bailoni

Western RidingWestern Riding Growing interest for western disciplines Growing interest for western disciplines

in Italy, particularly for reining and in Italy, particularly for reining and cutting, i.e. the most popular in USAcutting, i.e. the most popular in USA

Different nutritional management Different nutritional management among studs in Italyamong studs in Italy

Use of empirical knowledge onUse of empirical knowledge onhorse-feeding in general and inhorse-feeding in general and inparticular for Western Ridingparticular for Western Ridinghorseshorses

Background on Background on Western horse feedingWestern horse feeding Diets for the Western Riding horses Diets for the Western Riding horses

are usually formulated on the basis of are usually formulated on the basis of age and activity of horses (i.e., for age and activity of horses (i.e., for groups of animals)groups of animals)

NRC 2007: new nutrient requirements NRC 2007: new nutrient requirements equations, considering age, weight, equations, considering age, weight, growing rate and work intensitygrowing rate and work intensity

To verify Energy (DE) and Protein (CP) To verify Energy (DE) and Protein (CP) intakes in comparison with theoretical intakes in comparison with theoretical requirements of NRC (2007)requirements of NRC (2007)

To analyze relationship between To analyze relationship between intakes and requirements on the basis intakes and requirements on the basis of different ages and activities of of different ages and activities of horses horses

ObjectivesObjectives

Materials and MethodsMaterials and Methods 2 studs (A & B) located in northern Italy and 2 studs (A & B) located in northern Italy and

specialized for reining and cutting, respectively.specialized for reining and cutting, respectively. 62 athletic QH horses, aged between 2 and 8 62 athletic QH horses, aged between 2 and 8

yrs.yrs.

Trial lasted 5 months (from September to Trial lasted 5 months (from September to January), divided into 3 periods classified by January), divided into 3 periods classified by intensity of work:intensity of work:

1.1. Medium work (from September to October)Medium work (from September to October)2.2. Intense work (November)Intense work (November)3.3. Light work (from December to January)Light work (from December to January)

Age Class (yr) STUD A STUD B Overall2 20 7 273 5 9 144 3 6 95 2 4 66 2 28 4 4

Overall 30 32 62

Individual data Individual data recordingrecording

Use of specific forms to collect Use of specific forms to collect individually:individually:

Animals’ age class (2,…..,8)Animals’ age class (2,…..,8) Daily activity (in Daily activity (in arenaarena, horse walking , horse walking

machine or in machine or in round yardround yard)) Monthly estimated body weight (BW)Monthly estimated body weight (BW) Monthly body condition score (BCS, Monthly body condition score (BCS,

French method, 5 classes)French method, 5 classes)

Diets and Feeds recordingDiets and Feeds recording Daily amounts of single feeds administered to Daily amounts of single feeds administered to

horses were recordedhorses were recorded Samples of each feed were collectedSamples of each feed were collected

periodically and subjected to chemical analysesperiodically and subjected to chemical analyses Contents of nutrients were calculated on the Contents of nutrients were calculated on the

basis of chemical composition (NRC, 2007)basis of chemical composition (NRC, 2007) Dry matter (DM), energy (DE) and protein (CP) Dry matter (DM), energy (DE) and protein (CP)

daily intakes were estimated from mean daily daily intakes were estimated from mean daily allowancesallowances

Intakes were compared with theoretical Intakes were compared with theoretical requirements calculated on physical activities requirements calculated on physical activities and growth rates of each group and period and growth rates of each group and period

Statistical analysisStatistical analysis ANOVA using a split-plot model as follows:ANOVA using a split-plot model as follows:

yyijklijkl = = + + ii + + (())ijij + + kk + + ikik + + ijklijkl

Simple regressions were calculated between intakes Simple regressions were calculated between intakes and requirements within period and age for both DE and requirements within period and age for both DE and CPand CP

where:where: == overall mean; overall mean; ii== effect of stud (i=A, B);effect of stud (i=A, B);(())ijij == effect of age class within stud:effect of age class within stud:kk == effect of the period of activity (k=M, I, L); effect of the period of activity (k=M, I, L); ikik == effect of the interaction stud x period;effect of the interaction stud x period;ijklijkl == residual error ~N(0,residual error ~N(0,22))

Main resultsMain results Both weight, BCS and time of Both weight, BCS and time of

exercise changed between age exercise changed between age groups (mainly due to different groups (mainly due to different age classed) and period of activityage classed) and period of activity

A significant interaction Stud x A significant interaction Stud x Period for these variables was Period for these variables was detected observeddetected observed

3.75 3.75 3.75

3.423.38

3.53

3.20

3.30

3.40

3.50

3.60

3.70

3.80

BCS

(sco

re)

Stud A Stud BStud

Medium Intense Light

447.5 447.5 447.5

470.8

484.0

478.0

420

430

440

450

460

470

480

490W

eigh

t (Kg

)

Stud A Stud BStud

Medium Intense Light

Weight in Weight in different Period different Period

within Studwithin Stud

BCS in different BCS in different Period within Period within

StudStud

ANOVA for dry matter (DM), ANOVA for dry matter (DM), digestible energy (DE) and crude digestible energy (DE) and crude

protein (CP) intakes (variance and protein (CP) intakes (variance and P)P)

Relationship Relationship between intake and between intake and

theoretical theoretical requirements of DE requirements of DE in different activity in different activity

periodsperiods15

18

21

24

27

30

Light Moderate IntensePeriod

DE

(Mca

l/d)

Stud A Stud B DE Requirements

600

700800

9001000

1100

12001300

1400

Light Moderate IntensePeriod

CP (

g/d)

Stud A Stud B CP Requirements

Relationship Relationship between intake and between intake and

theoretical theoretical requirements of CP requirements of CP in different activity in different activity

periodsperiods

Relationship Relationship between intake and between intake and

theoretical theoretical requirements of DE requirements of DE

in different age in different age classesclasses

Relationship Relationship between intake and between intake and

theoretical theoretical requirements of CP requirements of CP

in different age in different age classesclasses

15

18

21

24

27

30

2 3 4 5 6 8Age (yrs)

DE

(Mca

l/d)

Stud A Stud B DE Requirements

600

700

800

9001000

1100

1200

1300

1400

2 3 4 5 6 8Age (yrs)

CP (

g/d)

Stud A Stud B CP Requirements

ConclusionsConclusions Results obtained in two big studs in northern Results obtained in two big studs in northern

Italy suggests that allowance of DE and CP Italy suggests that allowance of DE and CP calculated from intake are generally higher calculated from intake are generally higher than suggested requirements (NRC, 2007)than suggested requirements (NRC, 2007)

However, energy and protein surplus are not However, energy and protein surplus are not linked to weight or BCS changes or to some linked to weight or BCS changes or to some pathology (e.g., lameness), particularly in STUD pathology (e.g., lameness), particularly in STUD A, where allowances resulted much greater A, where allowances resulted much greater than requirement as compare with STUD Bthan requirement as compare with STUD B

Despite the need of more accurate studies Despite the need of more accurate studies involving higher no. of studs, animals and involving higher no. of studs, animals and longer periods, the present results suggest a longer periods, the present results suggest a possible energy and (partial) protein possible energy and (partial) protein underestimation of requirements in such underestimation of requirements in such category of athletic horses.category of athletic horses.

Thank you for your Thank you for your attention!attention!