Porcine Breeding Management in a Large-scale Piggery with Microbial Fermentation Bed

Bo LIU, Zhaolong LI, Jianyang TANG, Qinlou HUANG, Huiyong ZHENG, Jianglin LAN, Huai SHI, Boqi WENG, Wenquan YU

Fujian Academy of Agricultural Sciences, Fuzhou 350003, China

Alarge-scale piggery with microbial fermentation bed has been developed by Fujian Academy of Agricultural Sciences. This largescale microbial fermentation bed-equipped piggery covered an area of 1 800 m2. The single column could hold as many as 1 500 fattening pigssimultaneously[1]. The management of the large-scale piggery is different from that of the traditional piggery. In the traditional breeding model, single column usually holds 20-80 pigs. The swinery is relatively small and issue of management of large pig population is not involved in the traditional breeding model.The previous researches about management of growth characteristics of fattening pigs mainly focus on the addition of feed nutrition.Zhang et al.[2]studied the effects of different protein level in the feed on performance, immune function and expression of μ-calpain in gluteal muscle of fattening pigs.Yang et al.[3]investigated the effects of different mulberry powder adding level on the performance and meat quality of pigs.Xing et al.[4]studied the effects of allicin on the performance of pigs through adding the allicin into the feed.Ji et al.[5]investigated the effects of plant extract (O. vulgare oil, OE) on the pregnant-lactating sows.They also studied the effects of OE (alone or in combination with antibiotics) on the serum IGF-I concentration, growth performance and carcass quality of fattening pigs. Wang and Huang studied the effects of betaine on the performance, carcass quality and meat quality of fattening pigs. Song et al.[6]prepared the xylanase through the liquid fermentation of Aspergillus. They added the prepared xylanase into the wheat feed of fattening pigs and studied its effects on the performance and blood biochemical indices of fattening pigs.Tong et al.[7]investigated the effects of herbal extract on the performance and meat quality of fattening pigs. To perform effective management of the large swinery in a largescale piggery with microbial fermentation bed, the behaviors of eating,drinking, defecating and peeing of 1 500 pigs were for the first time observed. The special objective was to find some simple indicators that could reflect the health status of the large swinery and to propose management methods for the large swinery. To our knowledge, there have been no reports about the management of swinery in a large-scale piggery with microbial fermentation bed.

The management of growth characteristics of large swinery in a largescale piggery with microbial fermentation bed was started with the correlation between the growth days of age and feed intake of pigs. The swinery feed intake,the feed intake per pig,the water intake per pig and the health level as well as correlation between individual body length and individual BW were considered as the judging indicators.The correlation between the feed intake and growth of pigs was studied.In addition, the swiney growth and health status were observed. We hoped to provide experience for swiney performance management in a large-scale fermentation bed-equipped piggery.

Material and Methods

Microbial fermentation bed-equipped piggery and piglets

The large-scale microbial fermentation bed-equipped piggery was located in a farm in Xiali, Fuqing, Fujian Province. The breeding area of fermentation bed was 1 800 m2. The mattress materials were comprised of coconut husk (50%)and chaff (50%)and depth of the mattress was 80 cm.The piggery could hold 1 500 pigs.The piglets were 60 d old. Their average BW was 20 kg. The temperature and humidity in the piggery were controlled at 28 to 32 ℃and 70% to 90%, respectively.

Breeding of pigs in the microbial fermentation bed-equipped piggery

The automatic feeding system was adopted and all feeds were provided by the Fujian Hualong Group Feed Co., Ltd. All the feeds were suitable for raw feeding and dry feeding.It was unnecessary to cook and soak.At the very beginning, the feeding amount should be controlled. Then,the feeding amount was increased day by day.Clean water should be provided sufficiently. When the feed was changed from one kind to the other one,the crossed feeding of the 2 kinds of feed should be lasted for as long as 5 d. During this period, the original feed was replaced by the new feed gradually. The feed ingredients must be fresh.If the feed was mucid or deteriorated,it must be prohibited from utilization.The products should be stored in a dry and ventilated place to prevent them from moisture or mildewing.

Growth model establishment for pigs raised on the microbial fermentation bed

The information of the 1 to 56-day-old pigs was recorded (mid-June to mid-August). The information of the 56 to 155-day-old pigs raised on the microbial fermentation bed was obtained by in-situ observation (mid-August to mid-December). The feed intake of the 1 500 pigs on each day was recorded in details. Furthermore, 200 pigs were selected for the determination of indicators (BW, BW gain,breeding days, average daily feed intake,range of daily feed intake,staged feed intake, accumulated feed intake,feed/gain ratio) at different growth stages. Based on the acquired data,the growth models were established.

Eating behavior and occurrence of diseases among pigs in the microbial fermentation bed-equipped piggery

The swinery feed intake, feed intake per pig and water intake per pig were observed daily to validate the established models. Meanwhile, after the pigs entered the piggery, the incidences of diseases (pox-like macula(dermatitis), diarrhea (gastrointestinal disease), cough (respiratory disease),stiff pig (malnutrition), conjunctivitis(eye disease)and foot inflection(trauma)) were observed every 10 d till the 110thd, respectively. The occurrence regularity of the 6 kinds of diseases was studied further.

Results and Analysis

Growth indicators of pigs at different growth stages

The BW,BW gain,breeding days,average daily feed intake,range of daily feed intake, staged feed intake, accumulated feed intake and feed/gain ratio of pigs at different growth stages were shown in Table 1. For the 28-day-old pigs, the growth indicators were feeding days, 23 d; BW range,6-15 kg;average BW,6.5 kg;average BW gain, 5.5 kg; daily feed intake range, 0.23 -0.27 kg; average daily feed intake, 0.25 kg; feed/gain ratio,1.05. For the 98-day-old pigs, the growth indicators were feeding days,14 d; BW, up to 53 kg; average BW gain, 11 kg; daily feed intake range,1.9-2.1 kg;average daily feed intake,2.0 kg; feed/gain ratio, up to 2.55. For the 115-day-old pigs, the growth indicators were feeding days, 15 d;BW, up to 100 kg; average BW gain,12 kg; daily feed intake range,3.1-3.3 kg; average daily feed intake, 3.2 kg;feed/gain ratio, up to 4.00. The growth models were established for the pigs based on the analysis of acquired data,including the BW-age model, BW gain-age model,average daily feed intake-age model and feed/gain ratioage model.

Table 1 Growth characteristics of pigs raised in large-scale piggery with fermentation bed

BW-age model and BW gain-age model of pigs

The BW (y)-age (x) model was shown in Fig.1: y = 0.758 9x - 19.883(r2=0.993 7).The theoretical BW value of the 50,100 and 150-day-old pigs would be 18.062, 56.007 and 93.592 kg, respectively. Using this equation as a reference standard, if the pigs were to be slaughtered at the BW of 110 kg, the theoretical breeding days should be 171.146 d (x=(110+19.883)/0.759 8).

The BW gain (y)-age (x) model was shown in Fig.2: y=1.039 5x0.5051(r2=0.885 4). The theoretical daily BW gain of the 50, 100 and 150-day-old pigs would be 0.326(7.5 kg/23 d),0.75(10.5 kg/14 d)and 0.94 kg (13.2 kg/14 d), respectively. This model could be used as a reference standard for the daily BW gain of the pigs raised on the microbial fermentation bed.

Average daily feed intake-age model

The average daily feed intake (y)-age (x)model was shown in Fig.3:y=0.023 5x-0.334 3 (r2=0.991 7).The theoretical daily feed intakes of 60,65,70 and 75-day-old pigs would be 1.075 7,1.193 2,1.310 7 and 1.428 2 kg,respectively. This model could be used as a reference standard for the daily feed intake of the pigs raised on the microbial fermentation bed.

Feed/gain rate-age model

The feed conversion ratio (y)-age(x) model was shown in Fig.4: y =0.022 x + 0.427 8 (r2= 0.988 5). The theoretical feed/gain ratios of the 50,100 and 150-day-old pigs would be 1.527 8,2.627 8 and 3.727 8,respectively. This model could be used as a reference standard for the feed/gain ratio of the pigs raised on the microbial fermentation bed.

Validation of growth models for pigs raised in a large-scale piggery with microbial fermentation bed

The data were presented in Table 2. The observation was started at the age of 60 d since the pigs were born and ended at the age of 77 d. The swinery feed intake, daily feed intake and daily water intake were recorded in details.As shown in Table 2,the daily feed intake was increased with age increasing. The average daily feed intakes of 60,65,70 and 75-day-old pigs were 1.129, 1.442, 1.205 and 1.735 kg, respectively. According to the average daily feed intake-age model,the theoretical average daily feed intakes of 60, 65, 70 and 75-day-old pigs would be 1.075 7,1.193 2,1.310 7 and 1.428 2 kg, respectively. The actual average daily feed intakes of 60-65-day-old pigs were lower than the theoretical value, indicating that the pigs could not well adapt to the fermentation bed condition. The actual average daily feed intakes of 70 to 75-day-old pigs were higher than the theoretical average daily feed intake, indicating that the pigs had nicely adapted to thefermentation bed. Particularly, the average daily feed intake of the 75-dayold pigs was increased by 21%.

Dynamic monitoring of incidence of diseases among pigs raised in a large-scale piggery with microbial fermentation bed

During the whole breeding process, the pox-like macula (dermatitis),diarrhea (gastrointestinal disease),cough (respiratory disease), stiff pig(malnutrition), conjunctivitis (eye disease)and foot inflection (trauma)occasionally occurred among fattening pigs. The deadly infectious diseases had not been recorded(Table 3).

Table 2 Growth of 60 to 77-day-old pigs raised in large-scale piggery with fermentation bed

Table 3 Dynamic incidence among pigs raised in large-scale piggery with fermentation bed ‰

(1)The observation on the occurrence of pox-like macula (dermatitis)showed that the dermatitis was severe in the first 30 d after the pigs entered the fermentation bed-equipped piggery. The ten-day accumulated incidence range was 3% - 9%. After the 30thd, the dermatitis turned mild, and the incidences were all below 2.5%(Fig.5). The model of the dynamic incidence was:y=-0.325 8 x3+7.240 1x2-49.419x+125.56 (r2=0.925 7). Therefore, if the growth age is known, the theoretical incidence rate can be calculated.

(2)The observation on the occurrence of diarrhea (gastrointestinal disease) showed that the ten-day accumulated incidence of diarrhea (gastrointestinal disease) among pigs raised on the microbial fermentation bed was below 2.5% in general conditions(Fig.6),which was within the normal range. During the 50thto 70thd after the pigs entered the piggery,Fuqing district met two typhoons. The pigs might be humidified and chilly, resulting in the incidence of diarrhea be-ing once increased to 8%.

(3)The observation on the occurrence of cough (respiratory disease)showed that the incidence of cough(respiratory disease) among pigs raised on the microbial fermentation bed was below 2.5% in general conditions(Fig.7),which was within the normal range. During the 40thto 80thd after the pigs entered the piggery,Fuqing district met two typhoons. The pigs might be humidified and chilly, resulting in the incidence of cough (respiratory disease)being once increased to 8% -16% . The typhoon would sharply reduce the temperature in high-temperature autumn, resulting in the increased probability of occurrence of cough and other respiratory diseases among pigs. Therefore, a certain attention should be paid to strengthen the heat conservation and rainfall prevention.

(4)The observation on the occurrence of stiff pig (malnutrition) showed that the incidence of stiff pig(malnutrition) among pigs raised on the microbial fermentation bed was below 2.5%in general conditions (Fig.8), which was within the normal range. During the 30thto 60thd after the pigs entered the piggery,incidence of stiff pig(malnutrition) was once increased to 4%-6%. This might be due to the insufficient nutrition for the rapid growth of pigs.

(5)The observation on the occurrence of conjunctivitis (eye disease)showed that the incidence of conjunctivitis(eye disease) among pigs raised on the microbial fermentation bed was below 2.5% under normal circumstances (Fig.9), which was within the normal range. During the 30thto 80thd after the pigs entered the piggery, the pigs grew rapidly and the pig manure accumulation was increased. Meanwhile,the mattress was not plowed immediately, resulting in the incomplete fermentation of pig manure and increased generation of ammonia.Thus,the incidence of conjunctivitis (eye disease) was once increased to 3%-5%.Therefore,the strengthened management of the microbial fermentation bed mattress was critical for the reduced incidence of conjunctivitis (eye disease).

(6)The observation on the occurrence of foot inflection (trauma)showed that the incidence of foot inflection(trauma)among pigs raised on the microbial fermentation bed was lower than 2.5% under normal circumstances (Fig.10), which was within the normal range. During the 40thto 60thd after the pigs entered the piggery, the incidence of foot inflection (trauma)was once increased to 3%-5%.

Discussion

Growth curve of pigs raised in the large-scale piggery with microbial fermentation bed

Xiang et al.[8]studied the fitting growth curve of 44 new-line (B type)Jinhua reserve pigs (male, half; female, half). Zhang et al.[9]weekly determined average BW of 32 Bama miniature pigs (4 broods) selected randomly and fitted the recorded data with the Logistic and Gompatz models,respectively. Xu et al.[10]fitted the growth curve of 14 Duroc boars with the Logistic and Gompatz equations according to the 1 596 continuous daily BW records. Guan et al.[11]studied the growth and development of Hezuo pigs (remote piggery-raised plateau-type small pigs) and fitted the variation of BW with 3 nonlinear models: Logistic, Gompertz and Richards.Sun et al.[12]investigated the growth and development of 2 generations(120 pigs) of 20-day-old, 50-day-old and 25 to 90-kg-weighed high-quality line of Hubei white pig and fitted and analyzed the growth curve with the Logistic and Gompertz equations.They deduced the correlation formula of body weight-age for the 90-kgweighed pigs. Tao et al.[13]also fitted the growth curve of 90 Jinhua pigs with the Logistic and Gompertz equations at the fattening stage.

There have been no reports about the growth model of pigs raised in a large-scale microbial fermentation bed-equipped piggery. The range of BW, average BW, daily BW gain,breeding days, range of daily feed intake, average daily feed intake,staged feed intake, accumulated feed intake, feed/gain ratio and accumulated feed/gain ratio were studied in detail. Based on the acquired data, four growth dynamic models were established, respectively. The BW (y)-age(x) model (y=0.758 9x-19.883 (r2=0.993 7)), half-month BW gain (y)-age (x) model (y=1.039 5x0.5051(r2=0.885 4)), average daily feed intake(y)-age(x)(y=0.023 5x-0.334 3 (r2=0.991 7)), and feed/gain ratio (y)-age(x)(y=0.022 x+0.427 8(r2=0.988 5))were established to predict the theoretical BW,half-month BW gain,average daily feed intake and feed/gain ratio of pigs under a specific age, respectively. When the actual BW, halfmonth BW gain,average daily feed intake and feed/gain ratio of pigs were lower than the corresponding theoretical values,its reasons should be found out and the swinery management should be strengthened.

In order to understand the actual effect of the microbial fermentation bed on pig production, Huang et al.[14]divided randomly 100 DLY (Duroc ×Landrace × Yorkshire) crossbred pigs into 2 groups. They were raised with the same feeds in the microbial fermentation bed-equipped little-column piggery and traditional piggery, respectively.The effects of different piggery on the performance of fattening pigs were studied.The results showed that the feeding day required to grow to 100 kg was(170.67±3.31)d for the pigs raised on the microbial fermentation bed, which was shorter than that for the pigs raised in traditional piggery by 3.61 d(P ＜0.01).During the period in which the BW of pigs was increased from 30 to 100 kg,the daily BW gain of the pigs raised on fermentation bed was (731 ± 28) g, which was higher than that of the pigs raised in traditional piggery by 26 g(P ＜0.01).The feed/gain ratio of the pigs raised on fermentation bed was 2.94, which was lower than that of the pigs raised in traditional piggery by 0.17. Considering the whole breeding process (from sow-nursery pig to fattening pig), the pigs raised in the large-scale microbial fermentation bed-equipped piggery needed 155 d to grow up to 100 kg,which was shorter than that required by the pigs raised in the little-column microbial fermentation bed-equipped piggery by 15 d. The feed/gain ratio was 2.59,which was lower than that of pigs raised in the little-column microbial fermentation bed-equipped piggery by 0.35.Our results indicated that the effects of the large-scale microbial fermentation bed-equipped piggery(1 500 pigs) were better than that of the little-column microbial fermentation bed-equipped piggery(100 pigs).

Growth of pigs raised in the largescale piggery with microbial fermentation bed

Zhang et al.[15]selected 60 DLY crossbred piglets (male, half; female,half) which were weaned at 23-dayold. They were divided randomly into test group and control group. The pigs in the test group were raised on the microbial fermentation bed, and the pigs in control group were raised in the traditional piggery. The tests lasted for 137 d. The average daily BW gain of pigs raised on the microbial fermentation bed was increased by 6.76%compared to that of pigs in control group(P＜0.05),while the feed/gain ratio was decreased by 5.13% (P＞0.05).It was indicated the fermentation bed was safe in raising pigs. Moreover, it could significantly improve the performance of pigs. These results were consistent with those of our researches. The average daily feed intake of 60 to 65-day-old pigs was lower than the theoretical value predicted by the growth curve,indicating that the pigs could not well adapted to the fermentation bed condition at the very beginning. When the pigs grew up to 70 to 75-day-old,the average daily feed intake of pigs was higher than the theoretical value,indicating that the pigs had nicely adapted to the fermentation bed. In particularly, the average daily feed intake of 75-day-old pigs was increased by 21%, indicating that the fermentation bed was conducive to the growth of pigs. The average daily feed intake could reflect the growth of pigs to some extent. The application of the average daily feed intake-age growth model would play an important role in the management of pig population raised in the large-scale microbial fermentation bed-equipped piggery.

Dynamic analysis of incidence of diseases among pigs raised in the large-scale piggery with microbial fermentation bed

Zhang et al.[15]selected 60 DLY crossbred piglets (male, half; female,half) which were weaned at 23-dayold. They were divided randomly into test group and control group. The pigs in the test group were raised on the microbial fermentation bed, and the pigs in control group were raised in the traditional piggery. The tests lasted for 137 d.The results showed that the incidence of the test group was decreased by 26.47 compared to that of the control group in the nursery period;the incidences of the test group were increased by 42.29% and 39.50%compared to those of the control group in the growth stage and fattening stage, respectively. However, there was no difference in mortality between test group and control group.The incidence of diseases was increased in the late stage.These results were also similar to those of our studies.

Guo et al.[16]selected 84 DLY crossbred weaned piglets weighing(7.5 ± 0.2) kg. They were divided randomly into 2 groups. The pigs in the test group were raised on the microbial fermentation bed,and the pigs in control group were raised on the traditional cement floor. The basal diet was same. The results showed that the daily BW gain of the test group was significantly increased (P ＜0.05) compared to that of the control group;both feed/gain ratio and diarrhea ratio of the test group were significantly decreased (P ＜0.05); the E. coli amount in cecum and colon contents of the test group was significantly decreased(P ＜0.05); the amount of lactobacilli and bifidobacteria in cecum and colon contents of the test group was both increased significantly (P ＜0.05). The environment in the microbial fermentation bed-equipped piggery was significantly improved compared to that in the cement-floor piggery.For example,the temperature in the microbial fermentation bed-equipped piggery was higher than that in the cement-floor piggery(P ＜0.05).The ammonia concentration and suspended particle concentration in the microbial fermentation bed-equipped piggery were significantly lower than that in the cement-floor piggery (P ＜0.05). No parasite was detected in the fresh manure,fermentation bed mattress or cement floor.Our results indicated that the microbial fermentation bed could improve the daily BW gain of weaned piglets and decrease the feed/gain ratio and diarrhea incidence.The microbial fermentation bed could improve the intestinal microflora balance and the piggery environment.

The main diseases occurred in the fermentation bed-equipped piggery included pox-like macula (dermatitis),diarrhea (gastrointestinal disease),cough (respiratory disease), stiff pig(malnutrition), conjunctivitis (eye disease)and foot inflection (trauma).No deadly infectious diseases were found among pigs. The incidence of each disease was all lower than 10% with little difficulty in treating. If the management of mattress was strengthened, such as paying attention to feeding and keeping water clean,many diseases could heal themselves.The pox-like macula (dermatitis) was the severest in the first 10 d after the pigs entered the piggery. The incidence of dermatitis reached 8.5%.The diarrhea(gastrointestinal disease)was the severest on the 60thd after the pigs entered the piggery with incidence of 8.0%.The cough(respiratory disease)was the severest on the 70thd after the pigs entered the piggery with incidence of 17.0%. The stiff pig (malnutrition) was the severest on the 40thd after the pigs entered the piggery with incidence of 6.0%. The conjunctivitis(eye disease) was the severest on the 80thd after the pigs entered the piggery with incidence of 5.0%.The foot inflection(traumas)was the severest on the 40thd after the pigs entered the piggery with incidence of 5.0%.

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