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Revista MVZ Córdoba

Print version ISSN 0122-0268On-line version ISSN 1909-0544

Rev.MVZ Cordoba vol.24 no.2 Córdoba May/Aug. 2019

https://doi.org/10.21897/rmvz.1229 

Research article

Effect of blocks with calcium propionate on lamb productive performance and in vitro GHG

Nallely Sánchez L1 

Germán Mendoza M1 

José Martinez G2 

Pedro Hernández G3 

Luis Miranda R4 

Oscar Villarreal EB5  * 

1Universidad Autónoma Metropolitana Xochimilco, Departamento de Producción Agrícola y Animal, Doctorado en Ciencias Agropecuarias, CDMX., 04960, México.

2Universidad Autónoma Metropolitana Xochimilco, Departamento de Producción Agrícola y Animal, CDMX, México, 04960.

3Universidad del Estado de México, Centro Universitario Amecameca, 56900, México.

4Universidad Autónoma Chapingo, Departamento de Zootecnia, México, Edo. Mex., 56230, México.

5Benemérita Universidad Autónoma de Puebla, Facultad de Medicina Veterinaria y Zootecnia. Km. 7.5 Carretera Tecamachalco, Canada Morelos, El Salado Tecamachalco, Puebla, México 75480.


ABSTRACT

Objective.

Evaluate multinutritional blocks with and without calcium propionate (Ca-Pr) on digestibility and live weight changes of lambs and in the green house emission in vitro.

Materials and methods.

Twelve lambs were used (20.17±2.35 Katahdin x criollo) in three treatments: Basal diet (BD 70% oat straw, 30% concentrate), BD+ Block without Ca-Pr and BD+ Block with 1.5% Ca-Pr in 50 days assay. In vitro gas production (GP) and kinetic parameters were estimated (Vmax, S, Lag). In vitro and in vivo, CH4, CO2 and digestibility were estimated.

Results.

The dry matter intake was the lowest (p<0.0001) in lambs without block (753 g/d) compared lambs supplemented with block without (839 g) or with Ca-Pr (828 g); including blocks increased methane (16.16 and 16.18 g/d; 0 and 1.5% Ca-Pr respectively) than BD (13.93 g/d). The GP in vitro was higher (p=0.0001) with BD (380.76, ml) than with blocks without differences among blocks (335.76 and 341.13 ml, 0 and 1.5% Ca-Pr respectively), and the BD had higher (p=0.0001) production of CH4 (47.16 mol) and CO2 (200.04 mol) than with blocks (42.25 and 41.58 mol CH4; 179.21 and 176.39 mol CO2; 0 and 1.5% Ca-Pr respectively).

Conclusions.

Block supplementation improved dry matter intake. Blocks reduced in vitro gas production and increased digestibility by reducing CH4 and CO2.

Keywords: Additive; greenhouse gas; ruminant; supplement (Source: CAB)

RESUMEN

Objetivo.

Evaluar bloques multinutricionales con y sin propionato de calcio (Pr-Ca) en la digestibilidad y cambios de peso de corderos y en la emisión de gases in vitro.

Materiales y métodos.

Se utilizaron doce borregos (20.17 ± 2.35 Katahdin x criollo) en tres tratamientos: Dieta basal (DB 70% paja de avena; 30% concentrado), DB+ Bloque sin Pr-Ca y DB + Bloque con 1.5% de Pr-Ca, por 50 días. Se midió producción de gas (PG) in vitro y parâmetros de cinética (Vmax, S, Lag). Se estimó la digestibilidad, CH4 y CO2 in vitro e in vivo.

Resultados.

El consumo de materia seca fue menor (p<0.0001) en borregos sin bloque (753 g/d) en comparación con bloque sin (839 g) o con Pr-Ca (828 g) al incluir bloques aumentó metano (16.16 y 16.18 g/d; 0 y 1.5% Pr-Ca respectivamente) que con DB (13.93 g/d). La PG in vitro fue mayor (p=0.0001) con la DB (380.76 ml) sin diferencias entre bloques (335.76 y 341.13 ml, 0 y 1.5% Pr-Ca respectivamente), y la DB tuvo mayor (p=0.0001) producción de CH4 (47.16 mol) y CO2 (200.04 mol) que con bloques (42.25 y 41.58 mol CH4; 179.21 y 176.39 moles CO2; 0 y 1.5% Ca-Pr respectivamente).

Conclusiones.

La suplementación con bloques mejora el consumo de materia seca. Los bloques disminuyeron la producción de gas in vitro e incrementaron la digestibilidad reduciendo CH4 y CO2.

Palabras clave: Aditivo; gas efecto invernadero; rumiante; suplemento. (Fuente:CAB)

INTRODUCTION

Studies have been conducted to evaluate the contribution of ruminants to greenhouse gas (GHG) emissions and alternatives to mitigate this problem 1, which represent up to 12% of the energy consumed 2. To reduce these losses and make ruminant production more efficient, the use of additives has been evaluated 3,4, were sometimes have not improved yield 5 or fermentation 6 and the most efficient ones, such as Ionophores have been banned because are antibiotics. Calcium propionate (Ca-Pr) as an unconventional food ingredient has been used in lambs to reduce the use of grains, increasing ruminal propionate 7. Its potential to reduce methane is explained by the fact that during its dissociation captures a hydrogen ion, reducing its availability to form methane 8. The GHG emissions can be reduced if digestibility is improved, which is achieved by meeting nutritional requirements, particularly in ruminants fed diets low quality forages 9.

One option to an option to complement the deficiencies is to supplement with multinutritional blocks (MB) that have been evaluated worldwide 10, however, animal response has not been constant because for many years FAO promoted a block formula for all the conditions 11 when the nutrient requirements are different for each physiological stage with a diversity of basal diets. Therefore, the objective of this experiment was to evaluate multinutritional blocks formulated to improve lambs growth fed a basal diet with low nutritional value, with or without Ca-Pr, evaluating the impact on lamb growth, digestibility and in GHG emissions in vivo and in vitro.

MATERIALS AND METHODS

Location. This work was carried out in the facilities of the UAEM University Center in the Zootechnical Post of the Autonomous University of the State of Mexico, Amecameca, State of Mexico located in the south eastern zone of the State of Mexico.

Weather conditions. Subhumid temperate climate with an annual average temperature of 14.7°C.

Animals. Twelve Katahdin x creole lambs (20.17±2.35 initial weight) housed in individual cages with access to feed and clean water ad libitum were used. This work was carried out under the guidelines of the Academic Committee of the Department of Animal Science, in accordance with the regulations established by the Animal Protection Law of the State of Mexico, Mexico.

Treatments. The experiment lasted 50 days and lambs were distributed in a Completely Randomized Design (n=4 lambs) in three treatments: basal diet without supplement (BD: 70% corn stover, 30% concentrate, Table 1), BD with access a multinutritional block with or without 1.5% of Ca-Pr (Alimentaria Mexicana Bekarem, Mexico City) (Table 2).

Table 1 Composition of the basal diet (dry matter) concentrated forage (70:30). 

Table 2 Formulation of multi-nutritional blocks. 

a Vitasal Engorda Ovinos Plus contained: Ca 270 g, P 30 g, Mg 7.5 g, Na 65.6 g, Cl 100 g, K 0.5 g, S 42 mg, Fe 978 mg, Zn 3000 mg, Se 20 mg, Co 15 mg, vitamin A 35000 IU, vitamin D 1500000 IU and vitamin E 150 IU.

b Ovy ways 3 contained: Selenium 590 mg, Chromium 990 mg, Copper 1500 mg, Iron 3000 mg, Zinc 3000 mg, Manganese 3000 mg, Living yeast cells.

Basal diet and blocks were offered ad libitum. The basal diet was designed to simulate those offered in family-type production units (11% protein, 2.7 Mcal/kg DM ME). The multinutritional blocks (MB) were formulated so that when were supplemented fulfilled the nutritional requirements for lambs according to the NRC 12 for a weight gain of 150 g/d estimating an intake of 100 g/d block. The basal diet and blocks were analyzed to determine: dry matter (DM), organic matter (OM), crude protein (CP) 13, neutral detergent fiber (NDF) and acid detergent fiber (ADF) 14 (Table 3). The lambs were weighed with a 12-hour fast. On day 24, fecal samples were collected for four consecutive days to determine total tract DM digestibility using insoluble acid ash as an internal marker 15.

Table 3 Chemical composition of the basal diet and multi nutritional blocks. 

Ca-Pr:Block calcium propionate; DM: dry matter; OM: organic matter; CP: crude protein; NDF: neutral detergent fiber; ADF: acid detergent fiber; EE: ether extract.

CH4 and CO2 estimation in vivo. The IPCC equations were used 16 to estimate the ruminal CH4 using the annual emission factor (EF) per lamb, where the Ym or fraction for gross energy of the feed transformed to CH4 was calculated using the digestibility of each treatment with lamb's equations 17. Carbon dioxide emissions were estimated from the intake of digestible carbohydrates 18, which were used to estimate the moles of hexose fermented in the rumen using the molecular weight of anhydrous glucose 19. The fermentation pattern was from the forage: concentrated ratio and the produced moles of CO2 were calculated from the stoichiometric equations of Wolin 20.

Kinetics of in vitro gas. The gas production derived from ruminal fermentation was determined by the in vitro gas technique 21. The BD was used as substrate incubated with each MB in a proportion of 5% of the basal diet. Prior to incubation, the substrates were dried at 55 °C for 48 h in an oven and milled (<2 mm). In 500 ml amber flasks, 500 mg of each treatment were placed. Flasks were then incubated in anaerobic conditions with 90 ml of a diluted inoculum (1:10) of rumen bacteria obtained from two fasted lambs. The flasks were hermetically sealed and incubated at 39°C for 72 h in a water bath. The volume of gas produced was recorded at 2, 4, 6, 8, 12, 16, 20, 24, 30, 36, 42, 48, 60 and 72 h and the pressure values transformed to gas volume with the equation of linear regression, used to estimate the parameters of the gas production kinetics: maximum gas volume (Vm; mL g-1 DM of the substrate), gas production rate (S; h-1) and the lag time of the fermentation (L; h), with the model: Vo=Vm/(1+ e (2-4 * s * (t-L))) 21. At the end of the fermentation the residual dry matter (DM) was obtained to calculate in vitro dry matter digestibility (DIVDM) at 72 h of incubation; each treatment was incubated in triplicate.

CH4 and CO2 estimation in vitro. Those gases were estimated from the maximum gas volume; short chain fatty acids were calculated with the Getachew equation 22 and the proportion of CH4 and carbon dioxide with the stoichiometric factors 0.538 mmol for CO2 and 0.348 mmol for CH4 that have been described in other in vitro studies 23.

Experimental design. The data from each experiment were analyzed according to a Completely Randomized Design with a generalized linear model using each lamb as an experimental unit in the in vivo experiment or the test parameters obtained from the in vitro incubations, considering the treatments as fixed effects and random errors associated with each observation. The means of the treatments were compared using the Tukey test (p=0.05). For the in vivo experiment the initial weight was analyzed as a covariate using the JMP software 24. In vitro gas kinetics parameters were estimated for Vo=Vm/(1+ e (2-4 * s * (t-L))) using non-linear models of the JMP. A simple correlation between GHG results in vivo and in vitro was estimated.

RESULTS

The multinutritional blocks supplementation increased dry matter intake (p<0.01) by 10%, however, no differences were found in other variables (Table 4). Block supplementation did not reduce daily methane and CO2 emissions due to increased feed intake. The lambs that consumed blocks with Ca-Pr did not reduce intake nor had an effect on the estimated GHG emissions.

Table 4 Lamb performance and emissions of methane and carbon dioxide from lambs supplemented with blocks with or without calcium propionate. 

Ca-Pr: block calcium propionate; SEM: standard error of the mean; DM intake: dry matter intake; ADG: daily weight gain; FC: feed conversion, DM: dry matter; CH4: methane; CO2: carbon dioxide.

ab Means with different superscripts are different (p<0.05).

Table 5 shows the in vitro gas parameters. The basal diet resulted with a high volume of gas (p<0.001) and as a consequence, more moles of CH4 and CO2 were produced (p<0.0001). There were no differences between the blocks due to the inclusion of Ca-Pr. In vitro digestibility was not affected by block supplementation. In vitro digestibility values were correlated with those observed in vivo (r=0.9964, p=0.054), and in vivo digestibility was associated with daily weight gain (r=0.997, p=0.0434). The CH4 and CO2 emissions were positively correlated with the dry matter consumption (r=0.9921, p=0.07, r=0.9920, p=0.08). CH4 and CO2 in vivo and in vitro showed a high negative correlation (r=-0.99, p=0.07, r=-0.99, p=0.07).

Table 5 Parameters of in vitro gas production, methane and carbon dioxide, of basal diet incubated plus blocks with or without calcium propionate 

Ca-Pr: block calcium propionate; SEM, standard error of the mean; Vmax: maximum volume, S: gas production rate, Lag: delay time, DIVDM: in vitro digestibility of dry matter.

ab Means with different superscripts are different (p<0.05).

DISCUSSION

As observed in this experiment, it has been reported that MB stimulate intake 25 but there are studies where blocks had no effect 26. The composition of the blocks can modify intake 10; there are interactions between nutrient in the block and in the basal diet. In those studies, where intake was improved, generally a greater daily gains or final weight have been observed and in some cases, this is associated with greater digestibility 9 and nutrient consumption. In this study, the gain was improved by 35% but the low number of repetitions and the variation did not allow to detect differences. The type of block can have different effects on intake and digestion, by modifying the energy source, it was affected the block consumption without affecting digestibility 25.

The incorporation of Ca-Pr in the MB did not improve lamb performance or carbon dioxide emissions. If the values of CH4 and CO2 in vivo were expressed per kg of DM consumed, similar values would result (BD 1.84, 1.95 and 1.92 per MB with 0 or 1.5% Ca-Pr), indicating that the consumption of blocks and their additives were insufficient to modify the ruminal fermentation. In other evaluations, Ca-Pr did not affect the intake or lambs performance, 1% MS 7 and above 5.5% DM 27 the amount consumed in the MB was below of those studies. In vitro gas results indicate that MBs would reduce CH4, but in vivo values contradict this as they increase intake. Caution should be exercised in extrapolating the results of in vitro gas studies where no in vivo data are presented 28. With respect to other parameters of in vitro gas, it has been reported that 1% Ca-Pr increases the Lag phase but does not affect the fermentation pattern or CH4 losses 29.

In another in vitro study with 10% of Ca-Pr, the volume of gas increased, which was attributed to the effects on pH and osmotic pressure 8. In an in vivo evaluation with bulls receiving 20 g/d of Ca-Pr, did not affect fermentation or the microbial population 30, but the dose was very low.

The use of MB could reduce the lamb's time to reach the final weight by 44 or 60 days by supplementing without or with Ca-Pr respectively, reducing daily emissions, and could be an alternative to reduce global GHG emissions. Most studies focus on daily data, but it is important to consider the effects and their impact on global warming in terms of time 21.

In conclusion, supplementation with multinutritional blocks in low quality diets improved intake. In vitro the blocks reduced gas production and increased digestibility, so they could potentially reduce methane and carbon dioxide emissions.

Acknowledgements

To the National Council of Science and Technology (CONACyT Mexico). This research was partially supported by PROFIDES SEP Mexico and the Program for Professional Development Teacher, for the Superior Type (PRODEP). The authors thank Grupo Biotecap S.A. of C.V. For the donation of organic minerals.

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How to cite (Vancouver) Sánchez LN, Mendoza MG, Martinez GJ, Hernández GP, Miranda RL, Villarreal EBO. Effect of blocks with calcium propionate on lamb productive performance and in vitro GHG. Rev MVZ Cordoba. 2019; 24(2):7188-7192. DOI: https://doi.org/10.21897/rmvz.1229

Creative Commons Attribution 4.0 International License This article is distributed under the terms of the (https://creativecommons.org/licenses/by-sa/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source.

Received: June 01, 2018; Accepted: November 01, 2018; Published: April 01, 2019

* Correspondence: dr.oscarvillarreal@gmail.com

Conflict of interests

. The authors declare no conflict of interests

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