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Cuban Journal of Agricultural Science

Print version ISSN 0864-0408On-line version ISSN 2079-3480

Cuban J. Agric. Sci. vol.49 no.3 Mayabeque July.-Sept. 2015

 

ORIGINAL ARTICLE

 

Effects of a microbial preparation, a probiotic and commercial antibiotic on the productive performance and pigs health in post-weaning period

 

Efectos de un preparado microbiano, un probiótico y un antibiótico comercial en el comportamiento productivo y en la salud de los cerdos en etapa posdestete

 

 

L. Flores,I A. Elías,II F. Proaño,I G. Granizo,I Yolaine Medina,II Sandra López,I F. Herrera,II W. Caicedo,III

IEscuela Superior Politécnica de Chimborazo. Panamericana Sur km. 1 1/2, Riobamba, Ecuador.
II
Instituto de Ciencia Animal, Apartado Postal 24, San José de las Lajas, Mayabeque, Cuba.
IIIUniversidad Estatal Amazónica, Km 2 ½ Vía a Napo, Pastaza, Ecuador.

 

 


ABSTRACT

To measure the influence of a Stafac (Virginiamycin at 2%, 1 kg.t-1) commercial antibiotic, a  ML 100 E (1kg.t-1) commercial probiotic and a (15 mL.kg LW -1)  microbial preparation in the productive performance and health of post weaning pigs, an experiment by a complete randomized design, with three treatments and four repetitions was conducted. A total of 120 barrow pigs were used, from Landrace x Large White cross, with Belga x Pietrain sire at finishing stage, of 28d of age, 6.85 kg average weight and± 0.25 kg. In pigs feed concentrates to those that the microbial preparation was added, the higher final weight and the best gain of total weight and daily (P < 0.05): 25.85 kg, 18.97 kg and 440.75 g was determined, respectively. The most efficient values, as feed conversion, protein and energy, were obtained in the treatment to which the microbial preparation 1.66 kg DM.kg LW-1, 347.35 g.kg LW-1 of CP and 22.71 MJ.kg LW-1 was added, respectively. The less digestive problems presence (number of diarrhea) was registered in the group of animals fed with concentrate plus microbial preparation, with incidence of 13.With the addition of the microbial preparation, at 15 mL.kg LW-1,it can improve the concentrates nutritional quality and obtain  better productive and health parameters in post-weaning pigs, without using antibiotics.

Key words: microbial preparation, commercial antibiotic, post- weaning pigs, whey.


RESUMEN

Para medir la influencia de un antibiótico comercial Stafac (Virginiamicina al 2 %, 1 kg.t-1), un probiótico comercial ML 100 E (1kg.t-1) y un preparado microbiano (15 mL.kg PV-1) en el comportamiento productivo y en la salud de cerdos postdestete, se condujo un experimento mediante diseño completamente aleatorizado, con tres tratamientos y cuatro repeticiones. Se  utilizaron 120 cerdos castrados, del cruce  Landrace x Large White, con padre finalizador Blanco Belga x Pietrain, de 28 d de edad, 6.85 kg de peso promedio y ± 0.25 kg. En los cerdos alimentados con concentrados a los que se agregó el preparado microbiano, se determinó el mayor peso final y la mejor ganancia de peso total y diaria  (P < 0.05): 25.85 kg, 18.97 kg y 440.75 g, respectivamente. Los valores más eficientes, en cuanto a conversión alimentaria, proteína y energía, se obtuvieron en el tratamiento al que se adicionó el preparado microbiano: 1.66 kg MS.kg PV-1, 347.35 g.kg PV-1 de PB y 22.71 MJ.kg PV-1, respectivamente. La menor presencia de problemas digestivos (número de diarreas) se registró en el grupo de animales alimentados con concentrado más preparado microbiano, con incidencia de 13. Con la adición del preparado microbiano, a razón de 15 mL.kg PV-1, se puede mejorar la calidad nutricional de los concentrados y obtener mejores indicadores productivos y de salud en cerdos en posdestete, sin utilizar antibióticos.

Palabras clave: preparado microbiano, antibiótico comercial, cerdos posdestete, suero de leche.


 

 

INTRODUCTION

The antibiotics or antimicrobial have played an important function in the growth and development of the pork industry for more than 50 years. Its effectiveness, in terms of influencing in the growth rate increases, when improving food use and reduces mortality result of clinic illnesses, is well documented (Cromwell 2002). However, worries related with the bacterial strains development increase at present time, potentially resistant to antibiotics, that are related to the genes that influences in human health (Heo et al. 2012). Recently the current politicians about the use of antimicrobials in European Union and its effect on animal production have been checked. State and federal proposals have also been formulated, guided to restrict or drastically reduce the antimicrobials used as feed additives in United States (Clark et al. 2012).

The probiotics has consolidated as one of the natural alternatives to the use of antibiotics promoters of growth in animals, because they do not produce collateral effects and produce better digestibility, gain in weight and higher index of alimentary conversion (Gutiérrez et al. 2013). Probiotics, as live microbial additives, provides benefits to the animal health, because they improve their microbial intestinal balance. Its application in the feeding of weaning sucking piglets has allowed improving the zootechnical parameters alimentary conversion, final liveweight gain and immune response (Jurado et al. 2013). Vitafert has been developed in Cuba and applied on feeding different animal species and categoties (Elías y Herrera 2008)

In Ecuador, there have been used microbial preparation with excellent probiotic activity, based on whey, sugar cane juice and pigs feces as bio-accelerated. These, being rich products in organic and lactic acids and yeasts, improved the bio-preparation quality (Díaz 2011).

The objectives of this research were characterize chemical and microbiological, the microbial preparation, to compare the nutrients content of experimental diets and to evaluate the productive performance and health during the post-weaning period.

 

MATERIALS AND METHODS

Experiment location. The experiment was developed in the Biotechnology and Animal Nutrition laboratories and in the Academic Pork Unit, belonging to Cattle Sciences Faculty (CSF) of the Chimborazo Higher Polytechnic School, in Ecuador (CHHPS).

Experimental period 1. Preparation and characterization of the microbial preparation. This period lasted nine days. In plastic tanks, of 220 L capacity, fresh whey, molasses, urea, mineral salt and water were mixed, according to Diaz (2013) recommendations (table 1).

The whey was taken from the CSF industrial dairy, CHHPS. The molasses contained 85 Brix degrees. The urea contained 46% of nitrogen. The mineral salt was composed by 9% of calcium and 10% of phosphorous. Both were obtain in commercial way. The human consumption water was used and it was two hours rest before its use.

The mixture components were homogenized and were stayed with hermetic cover during 96h, at room temperature. For the product characterization, five samples were taken (200 mL).There were determined pH (WPA portable potentiometer); organic acids content, according to the technique propose by Erwin et al. (1961) and microorganisms recount: lactic bacteria, fungi and yeasts, according with Merck (2005) procedure.

For the microbial preparation, the statistic descriptive was used; the Infostat (2012) program was specifically applied.

Experimental period 2.Comparison of diets nutrients content. This period lasted 30 d. A concentrate in which was considered as basic diet (table 2) the one that maintain the same raw matter for the post-weaning period was formulated, due to the animals nutritionals requirements, according NRC (1998). Table 3 shows the nutritional contribution of the diet.

To estimate the nutritional influence that may cause the addition of the microbial preparation made by Diaz (2013), regarding the addition of an antibiotic cited by Cromwell (2001) and a probiotic referred by Allen et al. (2013), laboratory analysis were carried out for three treatments:

1- Concentrate  +  commercial antibiotic (Stafac is the trademark for Virginiamicina)

2- Concentrate + commercial probiotic (ML100 E).The commercial probiotic (More Yeast 100 E) is a combination of yeast culture with live cells of Saccharomyces cerevisiae, Bacillus subtilis and digestive enzymes (proteases, lipases, amylases and cellulaces).

3- Basic  concentrate + microbial preparation (15 mL.kg LW-1)

All treatments were subjected to proximal analysis, according to AOAC (2005).The in vitro digestibility of crude protein was determined by pancreatine pepsin technique (Dierick et al.1985) and true protein, according to Bernstein (1983).For the comparison of the nutrients content of experimental diets, means of each treatments were used, after analyzing the five samples.

Experimental period 3. Evaluation of productive indexes in fattening pigs. The initial weight, final weight, total weight gain, daily weight gain, dry matter conversion, protein conversion and energy conversion were evaluated, according to the treatments conception of the second stage. 

Experimental procedure. A total of 120 barrows pigs were used, Landrace-Large White x Belga-Pietrain cross, of 28d of age, with 6.85 kg ± 0.25 kg. Each experimental unit was composed of 10 pigs, housed in 2 x 2.25 m collective pens, with density of a pig for 0.45 m2.The animals received three experimental treatments. The food was offered every 24h during the morning 8:00 a.m. The water was ad libitum in nipple waterers.

Statistical analysis. For productive performance the co- variable analysis in the variables final weight, total weight gain, daily weight gain, dry matter conversion, protein conversion and energy conversion was carried out. The initial weight was took as concomitant variable, which not influence in the mentioned variables,  that is why variance analysis according to totally randomized design was carried out, according InfoStat (2012),with three treatments and four repetitions per treatment. Duncan (1955) test for (P < 0.05) was applied when it was necessary.

The theoretical suppositions of the variance analysis for number of diarrheas variable were analyzed. Shapiro and Wilk (1965) test for errors normality was used. The Levene (1960) test for the homogeneity variance that fulfill this suppositions was applied, which was not necessary to carry out its transformation (√x) by the statistical Software StatSoft, Inc. (2003). Later on, variance analysis was made, according to initially foreseen design.

 

RESULTS AND DISCUSSION

The microbial preparation had 3.8 of pH, after 96 h of fermentation. The lactic acid content was of 0.122 mg.mL-1, that of propionic 0.00367 mg.mL-1 and that of butyric 0.00037 mg.mL-1.The titratable acidity as lactic acid was of 3.26 %.The dry matter content, total nitrogen, protein and ammoniac, was of 21.23, 1.383, 0.953 and l0.184 %, respectively. That of CP, 8.64 %.

There was total absence of totals salmonellas and coliforms. The molds and yeasts content was in384 x 103 ufc.mL-1, 8.9 Brix degrees, and that of acid lactic bacteria 43.12 x103 ufc.mL-1

When comparing the microbial preparation with a biological lactic bacteria (mixed culture of  Lactobacillus acidophillus and Streptococcus termophillus), developed on a substrate that was elaborated by means of the homogenization of a mixture composed by final molasses, dry torula yeast and water, certain similarity was found. The bacteria concentration in the final product was between 108 and 109 ufc.mL-1 (Rodríguez et al. 2009).

The results of comparing the nutritious value of the experimental diets are showed in table 4.The humidity higher value was obtained with the inclusion of the microbial preparation. The commercial antibiotic showed higher DM content (P < 0.05).In relation to other treatments, the lower DM content was obtained by the microbial preparation addition, possibly due to the DM content of this latter, that was lower (21.23 %).Added to this, mainly, the hydrolytic activity of lactic acid bacteria and yeasts with CO2 and H2O production, as there were informed in other foods Asku et al. (2004), Nkosi (2009) and Weinberg et al. (2009).

The higher values in the ash content were obtained with the microbial preparation, followed by the commercial antibiotic and probiotic. The reduction in NFE was directly related with the dispersion effect produced by the crude protein increase (CP) (table 4). Likewise, true protein reached its higher value with the microbial preparation, in which, join to the aforementioned hydrolytic effect, was could produce the protein synthesis, due to the microbial growth. To this respect, Elías et al. (1990) showed that the efficiency for the true protein synthesis in the soluble carbohydrates conversion (contents in the NFE) was of 0.6 units.  

The concentrate plus commercial antibiotic, followed by the commercial probiotic and microbial preparation, was the one with higher fat content. As for the crude fiber content, the highest percent corresponded to the commercial antibiotic, followed by the microbial preparation and the commercial probiotic.

Regarding the variation obtained in the CP digestibility, table 4 shows that the most efficient value was for the concentrate plus the microbial preparation, followed by the concentrate plus the probiotic and the commercial antibiotic. The digestibility of the concentrate plus the microbial preparation increased in 1.6 regarding the concentrate plus probiotic and in 5.74 percentiles in relation to the commercial antibiotic. This reflects the enzymatic activity of the microbial preparation, according to that informed by Díaz (2013).

Productive performance. The results obtained during the experiment regarding the final weight are showed in table 5. It was verified that there were significant differences (P < 0.05) between the microbial preparation and the remaining treatments. The treatment with the inclusion of microbial preparation produced weight difference of 3.38 kg of LW regarding the probiotic group, and 3.36 kg in relation to the concentrate plus commercial antibiotic.

Regarding the total weight gain and the daily weight gain, significant differences (P < 0.05) occurred during the experimental period (28-70 d) between the microbial preparation treatment and that of antibiotic and probiotic, without existing divergences between these last two, with daily LW gain above 77.25 and 78 g.

In the variables daily dry matter intake, daily protein intake and daily energy intake, it was not carried out statistical analysis because there was not intra-treatments variability. Only the each treatment means were presented. The higher dry matter, protein and energy intake was for the microbial preparation. In table 5 is highlight that the best dry matter, protein and energy conversion was achieved with the microbial preparation addition. There were significant differences (P < 0.05) in relation to the commercial probiotic and antibiotic.

The obtained results in the experimental period agree with researches carried out by other authors, when increasing the daily mean gain (DMG) with the use of bacterial culture and yeasts (Prieto et al. 2014).In pigs, the sea B. pumillus strain is a fiable probiotic to be use in weaned pigs and shows its potential for its application as alternative in feeding, specifically to replace antibiotics. Tabasum et al. (2014) indicated that the supplementation of the diet with probiotics based on Lactobacillus possibility affects in weight gain and food intake, while the conversion index improved by probiotics based on Bacillus. Suo et al. (2012) determined better values for daily weight gain and alimentary conversion by Lactobacillus plantarum ZJ316 effect.

The number of diarrheas in the 43 d of study is showed in table 6. Significant differences between treatments were showed. The lower number of diarrhea corresponded to the treatment which the microbial preparation was added.

For the number of deaths indicator, a variance analysis could not carried out, since there was not intra- treatments variability. In the treatments in those that there was a great number of diarrhea deaths were caused. The results of this research coincide with the informed by Alonso and Cacique (2002), whose explained that enteric illnesses decrease the daily weight gain and the alimentary conversion, they increase the mortality, wastes number and animals with lower weights to the average. Also, they do not favor the increase in weight. Vrotniakienė and Jatkauskas (2013) stated that the animals treated with probiotics were able to defend against E.coli and diarrheas. Also, they produced higher growth rate and alimentary efficiency regarding to those that were not treated. Büsing and Zeyner (2014) showed that the E. faecium, DMS 10663 and NCIMB 10415 probiotics, control diarrheas and the sucking piglets yield. According to Suo et al. (2012), the diarrheas percent of sucking piglets decrease 7.06 % with the use of an antibiotic at 2.17 %, due to the effect of the L. plantarum ZJ316 use.

 It is possible that the results obtained in this research are directly related with the use of probiotics in pigs diets. During the first stages of life, these have beneficial effects on the improvement of the nutrients absorption in the small intestine, which is reflected in better zootechnical parameters and in diarrheas decrease, as Cortés and Gómez (2011) refers.

The obtained results in the experimental period agree with other authors that used bacterial cultures. Rodríguez et al. (2009) obtained better results in growth pigs, when using a Lactobacillus acidophillus and Streptococcus termophillus biological  preparation. Pérez (2008) considered that the inclusion of yogurt mixed strain (Lactobacillus bulgaricus/Streptococus thermophylus) for piglets under commercial pork production conditions improve the productive parameters of pigs at 70d of age. Roján (2009) found better response when evaluating the effect of a biological active product (Vitafert) on productive indicators and of health in pork pre- fattening.

It is concluded that the microbial preparation, when having organic acids of short chain, lactic acid bacteria and yeasts, improve the concentrates nutritional value, increase the CP digestibility, besides to improve the productive parameters and decrease the number of diarrhea in pigs during the pot- weaning
period.

From these results, it is recommended to continue the research about the action of this microbial preparation in other pigs categories, especially in fattening.

 

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Received: December 9, 2014
Accepted: March 23, 2015

 

 

L. Flores, Escuela Superior Politécnica de Chimborazo. Panamericana Sur km. 1 1/2, Riobamba, Ecuador. Email: luisgerardofloresmancheno@yahoo.es

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