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52a Reunião Anual da Sociedade Brasileira de
Zootecnia
Zootecnia: Otimizando Recursos e Potencialidades
Belo Horizonte – MG, 19 a 23 de Julho de 2015
Digestibility of diets containing calcium salts of fatty acids in Saanen goats 1
Bruna Susan de Labio Molina2, Claudete Regina Alcalde3, Ludmila Couto Gomes4, Bruna Hygino4, Sérgio
Mangano de Almeida Santos4, Caroline Isabela da Silva5, Layana da Silva Souza5
1
Parte de da dissertação de Mestrado da primeira autora, financiada pelo CNPq - Edital MCT/CNPq Universal 14/2010
Programa de Pós-Graduação em Zootecnia – UEM, Maringá-PR, Brasil, e-mail: [email protected]
3
Departamento de Zootecnia-UEM, Brasil. Bolsista Produtividade em Pequisa do CNPq. e-mail: [email protected]
4
Programa de Pós-Graduação em Zootecnia – UEM, Maringá-PR
5
Graduação no Departamento de Zootecnia – UEM, Maringá-PR
2
Abstract: The objective was to evaluate the inclusion of calcium salts of fatty acids (CSFA) in diets of Saanen
goats on the digestibility of dry matter and nutrients. Five lactating Saanen goats were distributed in a Latin square
design (5×5) of 21 days, 15 days for adaptation and six days for data collection. The treatments were diets: 0; 6.25;
12.50; 18.75 and 25.0 g CSFA/kg DM, respectively. The ingredients were: ground corn, soybean meal, mineralvitamin supplement and calcium salts of fatty acids. The oat hay was provided in a proportion of 570 g/kg DM.
Indigestible acid detergent fiber was used as internal marker to estimate the digestibility. Fecal samples were taken
during six consecutive days to obtain a composite sample per animal for each period. There was a quadratic effect
on digestibility of dry matter, organic matter, neutral detergent fiber and total carbohydrates with improvement
from the minimum points of 13.20; 13.30; 16.90 and 14.60 g CSFA/kg DM, respectively. The digestibility of crude
protein and non-fiber carbohydrates were not influenced by treatments; however, the ether extract digestibility
showed a positive linear response as function of the inclusion of CSFA. Total digestible nutrients presented a
quadratic effect with the minimum point of 9.80 g CSFA/kg DM. In conclusion, the inclusion of 25.0 g CSFA/kg
DM enhances the energy value of diets for lactating goats.
Keywords: digestion, goat, indigestible ADF, oat hay, protected fat
Digestibilidade de dietas contendo sais de cálcio de ácidos graxos em cabras Saanen
Resumo: O objetivo foi avaliar a inclusão de sais de cálcio de ácidos graxos (SCAG) na dieta de cabras Saanen
sobre a digestibilidade da matéria seca e dos nutrientes. Cinco cabras Saanen lactantes foram distribuídas no
delineamento em quadrado Latino (5×5) de 21 dias, 15 dias para adaptação e 6 dias para coleta de dados. Os
tratamentos foram as dietas: 0; 6,25; 12,50; 18,75 e 25,0 g SCAG/kg MS, respectivamente. Os ingredientes foram:
milho moído, farelo de soja, suplemento mineral-vitamínico e sais de cálcio de ácidos graxos. O feno de aveia foi
fornecido na proporção de 570 g/kg MS. A fibra em detergente ácido indigestível foi utilizada como indicador
interno para estimativa da digestibilidade. Foram coletadas amostras de fezes durante seis dias consecutivos para
obter uma amostra composta por animal em cada período. Houve efeito quadrático na digestibilidade da matéria
seca, matéria orgânica, fibra em detergente neutro e carboidratos totais, com melhoria a partir dos pontos de
mínimo de 13,2; 13,3; 16,9 e 14,6 g SCAG/kg MS, respectivamente. As digestibilidades da proteína bruta e dos
carboidratos não fibrosos não foram influenciadas pelos tratamentos, entretanto, a digestibilidade do extrato etéreo
mostrou resposta linear positiva em função da inclusão de SCAG. Os nutrientes digestíveis totais apresentaram
efeito quadrático com ponto de mínimo de 9,8 g SCAG/kg MS. Em conclusão, a inclusão de 25,0 g SCAG/kg MS
aumenta o valor energético de dietas para cabras lactantes.
Palavras–chave: cabra, digestão, FDA indigestível, feno de aveia, gordura protegida
Introduction
The quality of diets influences directly on the productive responses of ruminants. So, providing a diet with
high nutrients availability is essential to obtain great results for females with high potential of milk production, such
as Saanen breed.
Including calcium salts of long chain fatty acids; also called protected fat, in the diets is a nutritional
management strategy to improve the quality of the diet for lactating females. This complex is dissociated in the
acidic conditions of the abomasum, making the lipids available for digestion and absorption directly in the intestine
(Silva et al., 2007a).
This study was conducted with the objective to evaluate the inclusion of calcium salts of fatty acids in diets
of lactating Saanen goats on the digestibility of dry matter and nutrients.
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Página - 1 - de 3
52a Reunião Anual da Sociedade Brasileira de
Zootecnia
Zootecnia: Otimizando Recursos e Potencialidades
Belo Horizonte – MG, 19 a 23 de Julho de 2015
Material e Methods
Five multiparous Saanen goats (63.23 ± 9.08 kg of body weight and 105 ± 3 days of lactation) were
distributed in a Latin square design (5×5) of 21 days, which each experimental period was composed of 15 days for
the animals to acclimate to the diets and six days for data collection.
The treatments were diets: 0; 6.25; 12.50; 18.75 and 25.0 g of calcium salts of long chain fatty acids
(protected fat) per kg of dry matter (g CSFA/kg DM), respectively. The ingredients were: ground corn, soybean
meal, mineral-vitamin supplement and calcium salts of fatty acids. The oat hay was provided in a proportion of 570
g/kg DM (Table 1). The rations were adjusted to provide 700 g of total digestible nutrients/kg DM and 155 g of
crude protein/kg DM.
The goats were housed in individual pens, and access to the solarium in the morning. Goats were fed at 9h
and 16h with ad libitum water.
Table 1. Chemical composition of the experimental diets
Item (g/kg DM)
Oat Hay
Soybean meal
Ground corn
CSFAa
Mineral supplement®
0.00
570
187.9
232.4
9.8
6.25
570
185.1
229.0
6.25
9.6
Diets
(g CSFA/kg DM)
12.50
570
182.4
225.6
12.50
9.5
18.75
570
179.7
222.3
18.75
9.3
25.00
570
176.9
218.9
25.00
9.2
a
Protected fat - calcium salts of long chain fatty acids. Lactoplus®
To determine the digestibility of dry matter and the nutrients of the diets, fecal samples were collected from
the exit of the rectum to obtain a composite sample per animal, for each period, during six consecutive days at the
following times: 8h, 10h, 12h, 14h, 16h, and 18h.
To obtain the fecal excretion estimate, the indigestible acid detergent fiber (ADFi) was utilized as an internal
marker (Cochran et al., 1986) and was obtained after 240 hours of in situ incubation of feed, orts, and feces in F57
bags that were incubated in the rumen of goats. After, the acid detergent fiber was analyzed according to the
methodology of Ankom® (Ankom Technology Corporation, Fairport, NY, USA). Fecal excretion was estimated
according to Van Soest (1994): FE = iADFI / fiADF, where FE = fecal excretion (kg/d); iADFI = ADFi intake
(kg/d), and fiADF = fecal ADFi concentration (kg/kg).
The data were submitted to variance analysis via polynomial regression (P<0.05) by using the SAEG
(Genetic and Statistical Analyses System – UFV version 7.1) program.
Results and Discussion
The inclusion of protected fat in the diets promoted a quadratic effect (P<0.05) on digestibility of dry matter,
organic matter, neutral detergent fiber and total carbohydrates with improvement from the minimum points of
13.20; 13.30; 16.90 and 14.60 g CSFA/kg DM, respectively (Table 2).
Table 2. Digestibility of dry matter and nutrients, equation of regression, coefficient of determination (R²) and
coefficient of variation (CV) of diets containing calcium salts of fatty acids for goats
Diets
Item (g/kg)
(g CSFA/kg DM)
Equation of regression; R²
CV
0.00
6.25
12.50
18.75
25.00
Dry matter
649.5 623.2
611.4
637.3
635.2
Y = 646.5-4.17X+0.158X2; 0.65 2.93
Organic matter
659.1 635.2
621.9
648.0
645.5
Y = 656.6-3.99X+0.150X2; 0.64 2.88
Crude protein
755.9 740.5
720.6
757.3
743.2
Y = 743.5; nsa
2.50
Ether extract
719.7 773.5
795.1
852.0
861.9
Y = 727.8+5.81X; 0.96
3.75
Non-fiber carbohydrates 800.8 785.2
751.6
796.8
800.4
Y = 787.0; ns
5.21
Neutral detergent fiber
517.0 488.5
492.0
492.7
489.9
Y = 513.0-3.01X+0.089X2; 0.75 1.53
Total carbohydrates
634.9 606.3
592.8
612.7
610.8
Y = 632.3-4.64X+0.159X2; 0.77 3.08
Total digestible nutrients 639.1 622.6
614.7
647.9
651.8
Y = 636.8-2.94X+0.150X2; 0.72 2.96
a
ns = P>0.05
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52a Reunião Anual da Sociedade Brasileira de
Zootecnia
Zootecnia: Otimizando Recursos e Potencialidades
Belo Horizonte – MG, 19 a 23 de Julho de 2015
The digestibility of crude protein and non-fiber carbohydrates were not influenced (P<0.05) by treatments;
however, the ether extract digestibility showed a positive linear response as function of the inclusion of CSFA in
the diets. This effect is related to the greater concentration of unsaturated fatty acids that are available in the
intestine, which contributes to greater solubility in the micelles and, therefore, are more digestible when compared
to high saturated fatty acids (Palmquist & Mattos, 2011).
Silva et al. (2007b), when studying the effects of the inclusion of soybean oil, soybean grain, and calcium
salts of fatty acids in the diet of goats, also verified an increase in the ether extract digestibility with the
supplementation of 50 g CSFA/kg DM, when compared to the control diet; this was attributed to the increase in the
formation of monoglycerides in the intestine, which act as an emulsifying agent that facilitates the micelle
formation.
Therefore, in addition to the fact that they are more digestible, lipids contribute approximately 2.25 times
more energy than carbohydrates (Silva et al., 2007), which justifies the improvement on the total digestible
nutrients with the minimum point of 9.80 g CSFA/kg DM.
Conclusions
Calcium salts of long chain fatty acids enhances the energy value of diets for lactating goats, when included
up to 25.0 g CSFA/kg DM.
References
COCHRAN, R. C.; ADAMS, D. C.; WALLACE, J. D. AND GALYEAN, M. L. 1986. Predicting digestibility of
different diets with internal markers: Evaluation of four potential markers. Journal of Animal Science 63:14761483.
PALMQUIST, D. L. AND MATTOS, W. R. S. 2011. Metabolismo de lipídios. p.299-322. In: Nutrição de
Ruminantes. BERCHIELLI, T. T.; PIRES, A. V. AND OLIVEIRA, S. G. 2nd ed. Jaboticabal, SP, ed. Funep,
Jaboticabal.
SILVA, M. M. C.; RODRIGUES, M. T.; BRANCO, R. H.; RODRIGUES, C. A. F.; SARMENTO, J. L. R.;
QUEIROZ, A. C.; AND SILVA, S. P. 2007a. Suplementação de lipídios em dietas para cabras em lactação:
consumo e eficiência de utilização de nutrientes. Revista Brasileira de Zootecnia 36:257-267.
SILVA, M. M. C.; RODRIGUES, M. T.; RODRIGUES, C. A. F.; BRANCO, R. H.; LEÃO, M. I.; MAGALHÃES,
A. C. M. AND MATOS, R. S. 2007b. Efeito da suplementação de lipídios sobre a digestibilidade e os parâmetros
da fermentação ruminal em cabras leiteiras. Revista Brasileira de Zootecnia 36:246-256.
VAN SOEST, P. J. 1994. Nutritional ecology of the ruminant. Cornell University Press, Ithaca.
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