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Citation of this paper

Microbial biomass and growth performance of broiler chickens supplemented with fermented cheese whey in drinking water

Mustofa Hilmi, Muhammad Habbib Khirzin, Deni Yannuarista, Anis Usfah Prastujati and Asmaul Khusna

Study Program of Livestock Product Processing Tecnology, Politeknik Negeri Banyuwangi, Banyuwangi, East Java, Indonesia
mustofahilmi@poliwangi.ac.id

Abstract

Whey is a waste of liquid cheese or milk serum produced after being separated from curd containing lactose (4-7%) and protein (1 %) from the cheese-making process, which can be used as a medium for bacterial growth in the biologics fermentation process, which is very beneficial for improving poultry's performance and productivity. The research method used 3% fermented cheese whey in drinking water for broiler chickens aged 0-5 weeks to analyze microbes' performance and population in the digestive tract. This research aimed to determine fermented whey cheese concentration in broiler chickens' digestive tract, improving efficiency, carcass quality, and microbial population. The present is study used 330 broiler chickens aged 0- 5 weeks. The innovative method was designed using the T-test control method (CTL), fermented whey cheese whey (Yfw). The observed variables were performance (feed intake, body weight, feed conversion to ration), and microbiology of small intestine and excreta (lactate acid bacteria lactate, salmonella, Escherichia coli.) The consequence of adding fermented whey cheese to drinking water decreases the intake of feed and FCR and increases weekly body weight gain. Adding cheese whey fermented to drinking water decreases the number of Escherichia coli bacteria and increases lactic acid bacteria in broiler chickens' digestive tract, especially in the ileum, caeca, and stool. During the fermentation of whey cheese, the number of Salmonella bacteria decreased significantly, and lactic acid bacteria in the feces increased (p<0.01). Compared to the control group, the reduction in ammonia in the stool was very important. In conclusion, it can minimize feed intake, feed conversion ratio (FCR), Escherichia coli, salmonella, ammonia (NH3), and increase egg production, egg weight, egg mass weight, final body weight, and lactate acid bacteria through adding fermented whey cheese to drinking water.

Keywords: drinking water, fermented, broiler, whey cheese


Introduction

Whey is a waste of liquid cheese or milk serum produced from the cheese-making process after being segregated from curd, which contains carbon sources, lactose as an energy source in fermentation biotechnology manufacture of probiotics for livestock (Prasetyo and Kustiawan 2012; Nursiwi et al. 2015). According to Prasetyo and Kustiawan (2012), cheese whey includes lactose 4-7% and proteins 0.6-1%, which could be applied as a medium for bacterial growth in the fermentation process profitable for health and enhanced the productivity of organic livestock. The content of lactose and protein can be used to develop lactic acid bacteria and yeast (yeast) as a medium for developing biomass and producing several bioactive components through fermentation (Ariyanti and Hadiyanto 2013; Nursiwi et al. 2015; Watson et al. 2017; Hilmi et al. 2020). Several fermentation-derived bioactive elements, such as organic acids (lactic acids), active peptides, and proteins, function as antibacterial, antioxidant, and immune agents. Besides, Watson et al. (2017) that fermented products play a significant role in assisting the vitamin D and K absorption process, spurring beneficial tiny gut bacteria's growth and absorbing various micro-substances as minerals such as calcium and iron ions. This chemical/nutritional content can be utilized as a nutraceutical feed additive for livestock (Mellor 2000; Charalampopoulos and Rastall 2009; Kabir 2009; Sugiharto 2016; Watson et al. 2017). Nutraceutical feed additives do food/feed (or part of food) additives with medical or health advantages, including disease prevention and treatment and performance enhancement, and livestock development (Bhattacharyya and Roy 2015). Nutraceuticals are organic chemicals or natural feed ingredients that, by providing essential nutrition, can improve health by providing physiological benefits, one of which is by methods of fermentation, one of which is probiotics and organic acids. The influence of probiotics in poultry can positively impact livestock efficiency, productivity, and health. According to Kabir et al. (2005), probiotics may gain efficiency, carcass consistency, the number of lactic acid bacteria in the intestine, immune response, and reduced stress levels in broiler livestock. Probiotics containing lactic acid bacteria and yeast will increase eggs' development and inhibit growth in pathogenic bacteria's small intestine. Increased lactic acid bacteria and yeast also promote good bacteria development to increase egg production, which will increase protein absorption and digestibility capacity (Sathya and Muragian 2015; Lokapirnasari et al. 2017). According to Hilmi et al. (2020), the utilization of 3% fermented cheese whey can inhibit pathogenic bacteria in the digestive tract and increase lactic acid bacteria, increasing the productivity of laying hens. This research aimed to determine the concentration of fermented whey cheese in broiler chickens' digestive tract, which helps improve production, carcass quality, and microbial population.


Materials and methods

Ethical approval

The ethics committee of Politeknik Negeri Banyuwangi approved this study, and standards for animals' treatment and humane handling were strictly followed in the study (FASS 2010).

Birds, experimental diets, and design

The broiler chicken ration is formulated based on broiler chickens' needs, namely 18% protein and 2950 kcal/kg of metabolic energy (Table 1). Feeding and drinking water were administered ad libitum for approximately 35 days (5 weeks) of maintenance. Drinking water in treatment YFW was added 3% yeast- fermented whey to the water, while CTL only received plain water. The treatment diets were given at 06:30 and 16:00. Drinking water is delivered once a day at 07:00 in the morning. Feed consumption, weight gain, and mortality were reported each week. The parameters observed in this study were the broiler's performance, including feed consumption, body weight gain, feed conversion, and microbiology.

Table 1. Ingredient and nutrient composition of broiler chicken diets

Feed ingredients

(% air-dry basis)

Yellow corn

58.4

Soybean meal

22

Fish flour

4.5

Rice bran 

1.2  

CGM

2.8

Palm oil

2.65

DCP

0.99

CaCO3

6.7

NaCl  

0.3  

Premix

0.3

DL = Methionine

0.16

Proximate analysis (DM basis)

100

Metabolic energy (kcal / kg)

2951.75

Crude protein (%)

18.03

Crude Fat (%)

5.20

Crude fiber (%)

2.38

Methionine (%)

0.52

Lysine (%)

1.09

Cystine (%)

0.31

Methionine + Cystine (%)

0.84

Linoleic acid (%)

1.55

Ca (%)

3.11

P available (%)

0.53

Na (%)

0.18

Cl (%)

0.25

Note: The calculation result was based on Leeson and Summers (2009)

Whey cheese fermentation

Fermenting whey cheese included 10 minutes of whey cheese heated at 80°C, then 10 percent of molasses added. The temperature reduction was rapid to 35-40°C with immersion beaker glass containing a mixture of cold water and molasses. The next move was to add an inoculation starter to 5 percent containing lactic acid bacteria 8.28 log CFU/ml and yeast total of 7.93 log CFU/ml. The anaerobic fermentation of kefir was incubated for 24 hours at temperatures between 35 and 40°C after the inoculation process was completed. Following the incubation cycle's completion, an overview of the fermented whey cheese's consistency was conducted (Table 2).

Table 2. Properties of fermented cheese whey

Items

Contents

Alcohol (%)

3.18

Acetic acid (%)

0.21

Lactic acid (%)

0.29

pH

3.70

Titratable Acidity

0.579

Antioxidant

38.91

Lipid (%)

0.20

Protein (%)

0.27

Lactic acid bacteria (Log CFU/ml)

10.27

Total Plate Count (Log CFU/ml)

2.60

Yeast (CFU log/ml)

8.11

Analysis results according to Hilmi et al (2020)

Data analysis

All data are expressed as a mean ± standard deviation and analyzed using the T-test. The study was considered significant at p<0.05 using the Social Sciences Statistical Program (IBM SPSS version 21) for windows.


Results and Discussion

Effect of Fermented Whey cheese on Broiler Chicken Performance

The effect of adding fermented cheese whey to drinking water affects ( p <0.01) did not affect feed intake (Table 3; Figure 1) but improved live weight gain (Figure ) and feed conversion (Figure 3)., Taklimi et al. (2012) and Hilmi et al. (2020) stated that giving probiotics such as lactic acid bacteria and yeast will reduce feed consumption, in contrast to the research of the rise in body weight of chicken layers aged 1-5 weeks affected (p<0.01) and (p <0.05) by the intake of fermented cheese whey (P1) relative to the treatment of plain drinking water (P0). This rise in body weight was attributable to the quality of lactic acid bacteria and yeast in cheese whey fermented with kefir seeds, preventing pathogenic bacteria in the digestive tract, making it easier to consume nutrient degradation in the feed. Kefir is a natural product that includes a complex mixture of lactic acid bacteria and yeast that functions as a probiotic agent(Fuller 1989; Toghyani et al. 2015). Probiotics may improve intestinal health by inhibiting pathogen growth, ending in better digestion and nutrient absorption (Fuller 1989; Jin et al 2000; Chaucheyras-Durand and Durand 2009; Kabir 2009; Delia et al 2012; Toghyani et al 2015; Mousavi et al 2018; Hilmi et al 2020). According to Yaman et al (2006) and Hilmi et al (2020), drinking water kefir substantially increases the Lactobacilli spp and total aerobic bacteria and decreases the culture of Enterobacteriaceae to enhance the absorption of nutrients.

According to Huda et al (2019), the feed conversion ratio factor is acceptable nutritional content. Digestibility and metabolic energy, resulting in quicker food movements in the digestive tract (Jadhav et al 2015). The faster the feed rate movements would affect the absorption of nutrients used to produce eggs (Kabir 2009; Jadhav et al 2015; Mousavi et al. 2018). Besides, Toghyani et al (2015) and Hilmi et al (2020) argued that adding milk kefir and kefir molasses could reduce FCR due to an increase in microbiota in cultured milk beneficial for the absorption of nutrients in the body in order to reduce consumption.

Table 3. Effect of fermented whey cheese added to drinking water to performance chicken broiler

Items

Treatment

SEM

p

CTL

Yfw

Bodyweight (g/bird)

854.72

965.89

4,06

<0.000

Feed Intake (g/bird)

1330.94

1380.87

7.04

0.01

Feed conversion ration (g /g)

1.56

1.43

0.009

<0.000



Figure 1. Effect of yeast-fermented whey on
feed intake of broiler chicken
Figure 2. Effect of yeast-fermented whey on
live weight of broiler chicken

Figure 3. Effect of yeast-fermented whey on Feed
conversion of broiler chicken
Effect of Giving Fermented Whey Cheese on Microbes and Ammonia in Five Week Old Broiler Chickens

Microbiological analysis of broiler chickens aged five weeks can be seen in Table 4. Adding fermented cheese whey to drinking water affects (p <0.01) decreasing the number of Escherichia coli bacteria and increasing lactic acid bacteria in the digestive tract of broilers, especially in the ileum caeca, as well as with those in the stool. The number of Salmonella bacteria significantly (p<0.05) decreased and significantly ( p<0.01) increased lactic acid bacteria in the feces on the administration of fermented cheese whey. Ammonia reduction in feces was significantly affected (p<0.01) compared to control. Measurement of Power of Hydrogen (pH) in the gastrointestinal tract also affected (p<0.01) the decrease in the ileum and caeca digestive tract. The decline in the population of Escherichia coli bacteria in the intestine and salmonella in the feces was due to increased lactic acid bacteria, which produce various organic acid components such as lactic and acetic acid and reduce the pH value of the intestine (Engberg et al. 2009). According to Hilmi et al. (2020), adding 3% whey fermented cheese can reduce pathogenic bacteria and increase the population of lactic acid bacteria in the digestive tract. According to Canibe and Jensen (2003) and Kabir (2009), feed containing lots of lactic acid bacteria will produce high concentrations of lactic and acetic acids and lower the pH to form an environment that is hostile to the growth of gram-negative bacteria that are sensitive to acids such as Campylobacter, Salmonella, and Escherichia coli.

The increase in lactic acid bacteria in the feces will also affect the production of organic acids, breaking the chain reaction of urea formation. Yusrizal (2012) and Mi et al. (2019) stated that lactic acid bacteria could produce high acid, which is more effective in reducing ammonia in chicken feces so that the number of H+ ions is abundant. The H+ ion in chicken feces can convert ammonia to ammonium (NH 4+) so that the formation of ammonia emissions by gram-bacteria can be prevented (Kabir 2009; Pezzuolo et al 2019). Lactic acid bacteria act as an acid producers and are proteolytic to reduce ammonia because these bacteria can break down protein in uric acid. Uric acid, which is used to make ammonia in chicken feces, is broken down into monomers. Lactic acid bacteria use uric acid as a nutrient. It results in decreased ammonia production because uric acid availability, converted into ammonia, is reduced. Lactic acid bacteria also produce bacteriocins (antibiotics) that suppress gram-negative bacteria's growth, ammonia-producing pathogens (Dhama et al. 2011; Park et al 2016; Chen et al 2017). This suppression of bacterial growth results in a decrease in the urease enzyme production from gram-negative bacteria, converting uric acid to ammonia (Mi et al 2019; Pezzuolo et al. 2019). Mi et al (2019) stated that fecal pH plays a significant role in ammonia released in feces. Decreasing pH will change ammonia (NH3) to ammonium (NH4 +), which is more water-soluble, so it is less volatile than ammonia (NH3).

Table 4. The effect of giving fermented whey cheese into drinking water on the microbial population in the digestive tract of 5-week old broiler chickens

Items

Treatment

SEM

p

CTL

Yfw

The bacteria Escherichia coli (Log CFU/gram)

Ileum

5.79

5.13

0.09

<0.01

Caeca

7.37

6.31

0.16

<0.001

Lactic acid bacteria (Log CFU/gram)

Ileum

6.69

8.62

0.21

<0.001

Caeca

6.60

8.21

0.14

<0.001

Excreta (Log CFU/gram)

Lactic acid bacteria

5.82

7.48

0.14

<0.001

Escherichia coli

6.89

5.86

0.18

<0.001

Salmonella

4.49

3.6z

0.15

<0.001

Power of Hydrogen (pH)

Ileum

7,20

7.41

0.02

<0.001

Caeca

6.56

6.81

0.01

<0.001

NH3 (ppm)

4.09A

2.71

0.15

<0.001

Effect of Fermented Whey cheese on the quality of carcass and organs in broiler chickens

The effect of adding fermented cheese whey to drinking water affects (p<0.01) a rise in carcass percentage, HDL, and decreases abdominal fat, cholesterol, LDL levels (Table 5). In the small intestine and large intestine, the increased percentage of a carcass contains lactic acid and yeast bacteria capable of using the nutrients in the feed to be processed into many organic acids and proteins. This organic acid can suppress pathogenic bacteria and stimulate the growth of good bacteria that will improve absorption and digestibility to improve the quality of carcasses and protein (Sathya and Muragian 2015; Lokapirnasari et al 2017; Hilmi et al 2020). The use of lactic acid bacteria and yeast can generate an acidic atmosphere in the digestive tract, thus suppressing the growth of pathogenic bacteria (Hilmi et al. 2020) for the growth of poultry bodies, changing damaged tissue, and also for the production and components that make up eggs.

Lactic acid bacteria, which can prevent fat biosynthesis in the liver by developing lipase enzymes so that there is no accumulation of fat and cholesterol, are also responsible for decreasing cholesterol levels and abdominal fat levels in meat. According to Fadhilah et al (2015), lactic acid bacteria could produce cholesterol reductase enzymes, converting 14 cholesterol into coprostanol, a type of sterol that the small intestine cannot absorb. Furthermore, Loh et al (2013), cholesterol reduction is influenced by increasing lactic acid bacteria. Lactic acid bacteria will increase the cholesterol catabolism process into primary bile acids into various secondary bile acids with the ability to de-conjugate. This effect causes a decrease in the level of bile acids in the intestine. Besides, it increases fecal excretion and accelerates the circulation of bile acids. Its results in a faster rate of cholesterol synthesis for the production of bile acids due to their precursors' role in the synthesis of bile acids (Pereira et al 2002). Some Lactobacillus strains can produce exogenous polysaccharides, attaching to free bile acids in the intestine, thereby increasing bile acids' excretion through feces (Pigeon et al 2002). The negative correlation between lactic acid bacteria and cholesterol levels also supports the cholesterol-lowering effect in the gut. Apart from bile salt deconjugation, lowering cholesterol levels is another way to integrate cholesterol into the bacterial cell membrane (Noh et al 1997).

Table 5. The effect of giving fermented whey cheese into drinking water on the quality of carcass and organs in the digestive tract of broiler chickens aged five weeks

Items

Treatment

SEM p

CTL

Yfw

Carcass (%)

70.69

72.18

0.15

<0,000

Abdominal Fat

1.48

1.33

0.13

0.02

Total cholesterol

159.96

125.29

1.19

<0.000

Low Dessity Lipoprotein (LDL) (mg/dl)

125.29

120.71

1.14

<0.000

High- D esnsity L ipoprotein (HDL) (mg/dl)

30.25

34.01

0.51

<0.000

Small intestine (cm)

3.62

4.49

0.09

<0.000

Deudenum (cm)

0.57

1.22

0.01

<0.000

Jejenum (cm)

1.48

2.68

0.12

<0.000

Ileum (cm)

1.70

2.42

0.48

<0.000

Cecum (cm)

0.47

0.71

0.05

<0.000


Conclusion

Adding yeast-fermented cheese whey to the drinking water decreases intake of fed, improved weight gain and feed conversion, decreased the number of Escherichia coli bacteria, and increased lactic acid bacteria in broiler chickens' digestive tract, especially in the ileum, caeca, and excreta. During the fermentation of cheese whey, the number of Salmonella bacteria was decreased and lactic acid bacteria in the excreta increased. Compared to the control group, the reduction in ammonia in the excreta was very important. There was an increase in production, weight and egg mass due to fermented yeast supplementation.


Acknowledgment

Thanks to the Politeknik Negeri Banyuwangi for funding given in the RIP Research program 2020.


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