In 2001, Thuy Phuong Pig Research Center Took Over Vietnam PIC Company of England in Tam

1

INTRODUCTION

1. THE RATIONALE

In the world, pork accounts for the highest percentage (37,70%), followed by beef (29,10%), poultry meat (28,30%), and the rest is other kinds of meat (4,9%) (Do Kim Tuyen, 2010). In Vietnam, pork shares 70-75% of the total meat produced. Local pigs is small withhigh fat, less lean meat, so their pork can not meet the demand of current domestic market when the living standard and economy are enhanced. Since the 70s of the 20 century up to now, Vietnam has imported many exotic pig breeds such as Yorkshire (Y). Landrace (L), Duroc (Du), Pietrain (Pi)... from former Soviet Union’s countries, Cuba, Japan, Canada, Belgium, Denmark, Norway, America, France, Thailand ,etc.. with the purposeof improvingthe productivity and quality of local breeds, and also creatinglines, crossbred groups of high yield exotic pigs for the industrial pig sector. Due to the contribution of imported breeds together with the application of scientific advances in the country and over the world in fields of animal genrticd and breeding, animal feed and nutrition, advanced techniques in animal husbandry, housing, veterinary services and management, the productivity and quality of pig herds in Vietnam have achieved encouraging results. Pork production in Vietnam has basically met the demand of domestic market; however, due to the low quality of meat and high prices, the competivenessof pork has not been strong enough to compete with a similar product in the regional and internaltional markets.

In 2001, Thuy Phuong Pig Research Center took over Vietnam PIC company of England in Tam Diep-Ninh Binh.In 2008, 5 old grandparent lines were renamed such as L11 (synthesis Yorkshire) into VCN01, L06 (synthesis Landrace) to VCN02, L19 (synthesis Duroc white boar) to VCN03, L64 (synthesis Pietrain boar) to VCN94 and L95 (synthesis Meishan) to VCN05. From 5 old grandparent lines, grandparent sow lines were created, for eaxample VCN11 (it was renames from C1050), VCN12 (it was renames from C1230) and parent sow lines such as VCN21 (it was renames from C22), VCN22 (it was renames from CA).

Annualy, Thuy Phuong Pig Research Centre has transfers thousands of VCN22, VCN21 pigs torespone the needs of sow raising and to generate commercial exotic crossbred pigs for farmers in many provinces across the country. According to the breeding procedure inVietnam PIC breeding systems, VCN21 and VCN22 sows are inseminated with VCN23 terninal boars (renamed from terminal boars 402), which was crossbred boar(VCN04xVCN01), for producing commercial hybrid pigs of 4 and 5 breeds.

Currently, terminal breeding boars VCN23 have not been enough to supply for mating parent sows VCN21 and VCN22 to produce commercial crossbred pigs of many exotic breeds. On the other hand, to enrich genetic resources of terminal high-yield breeding boars for mating with sows VCN21 and VCN22 and for creating commercial pigs the North, this study entitled: “the reproductive performance of VCN21, VCN22 sows mated with PiDu boars and the productivityof PiDu x VCN21 and PiDu x VCN22 crossbred pigs” was undertaken

2. OBJECTIVESOF THE STUDY

To evaluate the reproductive performance of VCN21 and VCN22sows mated with PiDu boars

To valuated the growth performance of Pidu x VCN21 and PiDu VCN22 crossbred pigs

To evaluatedof carcass performance, meat quality ofPiDu x VCN21 and PiDu x VCN22 crossbred pigs

To evaluated the preliminary economic efficiency of fattening pig production at different slaughter weights of PiDu x VCN21 and PiDu x VCN22 crossbred pigs.

3. SCIENTIFIC AND PRACTICAL MEANINGS OF THE STUDY

3.1 Scienctific meanings

The first time in Vietnam, data on the reproductive performance of VCN21, VCN22 sows mated with PiDu boars, and the growth performance, carcass yield, meat quality and economic efficiency of pig fattening at 3 different slaughter weights 90,100 and 110 kg of PiDu x VCN21 and PiDu x VCN22 crossbred pigs was published.

Results of the thesis can be usedas references, and was valuable forlivestock research and aducation in production.

3.2 Practical meanings

Results of the thesis can work as source of scientific-based information on performance (reproduction, growth, carcass yield and meat quality) of VCN21 and VCN22 sows mated with PiDu boars for pig farmsto select suitable crossbred groupsand contribute to enhance reproductive performance, carcass yield, meat quality and to development of pig production in North, Vietnam.

Results of the thesis can also provide pig producer s and farmer with some indication on how diferrent slaughter weights: 90,100 and 110 kg of PiDu x VCN21 and PiDu x VCN22 crossbred pigs may affect economic efficiency of pig production

4. NEW CONTRIBUTIONS OF THE STUDY

A sysematicaly and relatively complteted evaluation on the reproductive performance of VCN21, VCN22 sows mated withPiDu boars and the growth, carcass performance and meat quality of PiDu x VCN21 and PiDu x VCN22 crossbred pigs was made in the thesis.

Initialeffect of 3 differrent slaughter weights 90,100 and 110 kg of PiDu x VCN21 and PiDu x VCN22 crossbred pigs on economic efficiency of pig production was examined.

Enriching genetic resources of terminalbreeding boars,which was used to mate with sows VCN21 and VCN22 in order to produce crossbred fattening pigs witha economic efficiency.

Based on the productive potential evaluation of PiDu boars mated with parent sows VCN21 and VCN22, the study proposed the way of using them to improve the performance and quality of exotic pig production in the North of Vietnam.

CHAPTER I.LITERATURE REVIEW

Different pig breeds hadtheir different reproductive performance (Tran Thi Minh Hoang et al., 2006, 2008; Rothschild and Bidanel, 1998). External factors such as feed, season, temperature, boar, feeding regime and parity could affect the fertility of sows: (Zimmerman et al., 1996; Koketsu et al., 1997; Pham Thi Kim Dung and Tran Thi Minh Hoang, 2009; Pholsing et al., 2009; Tran Thi Minh Hoang et al., 2008; Tretinjak et al., 2009). Different pig breeds haddifferent growth potential (Evan et al., 2003; Labroue et al., 2000). External factors such as nutrition, age, slaughter weight, season, animal husbandry, and sex has also affected the growth potential of crossbred fattening pigs (Wood et al., 2004; Larzul et al., 1998; Huang et al., 2004; Goft et al., 2003; Evan et al., 2003). Different pig breeds has had different carcass performance and meat quality (Evan et al., 2003; Collin, 1998;Puigvert et al., 2000). External factors has influenced carcass performance and meat quality(Wood et al., 2004; Geesink et al., 2004). Carcass yield depended on slaughter age (Latorre et al., 2004; Nguyen Van Duc,.2001; Piao et al., 2004; Neill et al., 2003). Seasonal factor has also affected carcass yield and meat quality (Huang et al., 2004; Guardia et al., 2004; Neill et al., 2003). Caring and husnandryaffected performance and meat quality (Turner, 2003)

Slaughtering condition influenced meat quality (Guardia et al.,2004; Neil et al., 2003; Tomoyuki Okumura et al.,2003). Sex affected meat quality (Guardia et al., 2004). Economic efficiency of an economic phenomenon (or a process) is a category that reflectslevels of resources utilization (human, finance, materials, capital) in oder to achieve identified objectives. The gerneral formula of economic efficiency (H) = results obtained from the economic phenomenon (process) (K) divided by total costs of the results (C). Costs in fattener production include: breed, feed, medicine and veterinary materials, labor, housing depreciation, loan interest rate, treating animal waste, energy for production (electricity, petrol, oil), transportation vehicles, cheap and perishable items, workwear, stationery. The product of fattening production is amount of gain live weights of pigs in kg sold. Additioally, manure and amount of gas produced from biogasdigester if using Biogas are aslo the products obtained. Net profit is the difference between the total revenue in cash (the gross) from selling pork, manure, gas (if any) and the total amount of money invested in the production process. Profit margin (Hp) is used as a general index of economic efficiency of the production, completely expressing the level of utilization of all factors in the production. Profit margin is calculated as calculates as follow:Hp = (Π/P) x 100. Hp: profit margin; Π net profit and P is total costs of the production. (Andrei Petrov Andreev et al., 1982). Therefore, the economic efficiency of pig fattening production is calculated by profit margin: the ratio of net profit/total costs x 100.

CHAPTER II. MATERIALS AND METHODS

2.1.MATERIALS

VCN21, VCN22 sows; PiDu boars and commercial crossbred pigs of PiDu x VCN21 and PiDu x VCN22 were used in this study.

2.2 LOCATION AND DURATION

Location: Thuy Phuong Pig Research Center- Thuy Phuong-Tu Liem-Ha Noi; Limited company Hung Tuyen-Tam Diep-Ninh Binh;Livestock and Technology Transfer Joint Stock CompanyYen Dinh-Thanh Hoa; industrial livestock group Dinh Long-Yen Dinh-Thanh Hoa; breeding pig farm No. 1- Gia Khanh – Binh Xuyen-Vinh Phuc; agricultural service and production cooperative ,Cong River-Thai Nguyen; Thai Viet Co., LtdCao Ngan - Đong Hy - Thai Nguyen

Duration: from 03/2010 to 05/2016

2.3 RESEARCH CONTENTS

Evaluation of the reproductive performanceof sows VCN21 and VCN22 mated with PiDu boars

Evaluation of the growthpotential of crossbred fattening pigs(PiDu x VCN21 and PiDu x VCN22)

Evaluation of the carcass performance and meat quality of PiDu x VCN21 and PiDu x VCN22

Evaluation of the economic efficiency of PiDu x VCN21 and PiDu x VCN22 at different slaughter weights

2.4 METHODOLOGY

2.4.1 Evaluation of the reproductive performanceof sows VCN21 and VCN22 crossing PiDu boars

2.4.1.1 Animals

The sow VCN21 (180 sows with 1080 litters), sow VCN22 (179 sows with 1074 litters) mated with PiDu boars were used in this experiment.

2.4.1.2 Experimentaldesign

The experimentswas arranged as the factoral designed experiment (1 factor: VCN21 or VCN220 each factor haing 3 levels: farm (province), parity, season).The season in this studywas divided into 4 seasons: Spring (months 2, 3 and 4), summer (months 5, 6 and 7), autumn (months 8, 9 and 10) and winter (months 11,12 and 1).

Parameters measured and obsevered included: the age at first mating (days);age at first farrowing(days); number of born piglets/litter (head); number of alive born piglets/litter (head); number of weaning pig/litter (head); percentage of piglets alive at weaning time (%); piglet weight at birth/piglet (kg); piglet weight at birth/litter (kg); piglet weight at weaning (kg); weaning weight/litter (kg); weaning age (days); farrowing interval (days), weaning-to-estrus interval (days).

Data collection: collecting inherited data on reproductive performance of sows VCN21 and VCN22 of farms from 3/2010 to 10/2012 through a system of recording notebooks and Excel file of data in the computer of the farms. Collaborating with farms to observe, weigh and record data on the reproductive performance of sows VCN21 and VCN22, from November 2012 to May 2016.

Data analysis: Data was analysed using SAS 9.1 sofware (2002). LSM was compared by Turkey technique. The data was analyzed after being eliminated values outside the range of X ± 3δ. Statistical model analysed factors affecting reproductive parametters of sows VCN21 and VCN22 as follows:

yijkl =  + Di + Tj + Lk + Ml + ijkl

where: yijkl: reproductive performance of sows; : mean value of the population; Di: the effect of the sowgroup i (i = 2; VCN21 và VCN22); Tj: effect of farm j (province) (j = 5: Ha Noi city, Ninh Binh, Thai Nguyen, Thanh Hoa, Vinh Phuc); Lk: effect of parity k (k = 6: 1, 2, 3, 4, 5 và 6); Ml: effect of seasonal factor l (l = 4: spring, summer, autumn, winter); ijkl: random error.

2.4.2 Evaluation of the growth capacityof crossbred fatteners PiDu x VCN21 and PiDu x VCN22

2.4.2.1 Animal

The experiments was arranged as the factoral designed experiment (1 factor: VC PiDu x VCN21 and PiDu x VCN22, each factor having 3 levels: crossbred group, sex and slaughter weight). Total of 480 crossbred fatteners PiDu x VCN21 and PiDu x VCN22, 240 heads for each crossbred group, of which 80 heads for each level of slaughter weights 90, 100 and 110 kg, with 4 replication of 20 animals (10 females and 10 castrated males were used in this study.The study was carried out at the breeding farm No.1 Gia Khanh- Binh Xuyen district- Vinh Phuc province, 2012-2016

2.4.2.2 Experimental design

Pigs raised were arranged in a completed randomly designedexperiment. The nutrient requirement for fattening pig was according to Vietnamese standard(TCVN 1547: 2007).

Parameters measured and obsevered included: initial weight (kg); initial age (days); age at the end of experiment (days); weight at the end of experiment (kg); average daily gain (gram/pig/day); feed conversion ratio (kg feed/kg daily gain).

Data collection: initial weight (kg); initial age (days); age at the end of experiment (days); weight at the end of experiment (kg) were individually mesasured and recorded, ADG and FCR were calculated.

Data analysis: data was analyzed using sofware SAS 9.1 (2002). Comparing LSM values was performed with Turkey technique. The data was processed after being eliminated values outside the range of X ± 3δ. Statistical model analysed factors affecting reproductive parametterss of sows VCN21 and VCN22

yijk =  + Di + Kj + Tk + ijk

where, yijkl: indicators of the growth performance; : mean of the population; Di: effect of the crossbred group i (i = 2; PiDu x VCN21 và PiDu x VCN22); Kj: effect of different slaughter weights j (j = 3: 90,100 and 110 kg); Tk: effect of sex k (k = 2:female and male pig); ijk: random error.

2.4.3 Evaluation of carcass yield and meat quality of two crossbred pigs PiDu x VCN21 and PiDu x VCN22

2.4.3.1 Animals

The experiment was conducted on crossbred pigs PiDu x VCN21 and PiDu x VCN22 after finishing the fattening period in December 2015. the number of pigs slaughtered for testing was 24 heads. Of which, 12 heads for each crossbred group, 4 heads (2 gilts and 2 castrated male pigs) for each slaughter weight level.

2.4.3.2.Exerimental design

Pigs selected for slaughter had average weights representing each slaughter weight level: 90,100 and 110 kg. Slaughtering procedure and parametter for carcass yield and meat qualitywas carried accordingo a testing slaughter process (TCVN 3899-84)

Parameters measured and obsevered: and collection live weight individually before slaughtering.carcass weight, weigh of hair, nternal organs, kidneys and fat, dressed carcass weight,carcass length, loin eye area,backfat thickness, pH45 after slaughter, pH of loin eye were mearured and recorded according to suitable method and equipments.

pH24, colour including: Lightness (L*); Redness (a*); Yellowness (b*). Cooler and processing shrink rates (%), Meat tenderness of loin muscle (N), e.t.c. were also measured according to suitable method and equipments.

Data analysis: data was analyzed using sofware SAS 9.1 (2002). Comparing LSM values was performed using Turkey techique. The data was processed after being eliminated values outside the range of X ± 3δ. Statistical model analysises factors affecting carcass yield, meat quality of crossbred fatteners VCN21 and VCN22

yijk =  + Di + Kj + Tk + ijk

where, yijk: parametters of carcass yield, meat quality; : mean of the population; Di: effect of the crossbred group i (i = 2; PiDu x VCN21 và PiDu x VCN22); Kj: effect of slaughter weight j (j = 3: 90,100 and 110 kg); Tk: effect of sex k (k = 2:female and male pig); ijk: random error.

2.4.4 Economic efficiency of two crossbred pigs PiDu x VCN21 và PiDu x VCN22 at different slaughter weights

2.4.4.1 Animals

The number of pigs raised in experiment 2.4.2 was used to calculate economic efficiency of crossbred pigs PiDu x VCN21 và PiDu x VCN22 at different slaughter weights.

2.4.4.2 Methodology

The economic efficiecy was calculated for each batch of pig (10 pigs/batch).

Parametters measured and calculated:breed cost = number of fatteners x price of a piglet; feed cost = total feed used x feed price; labour cost = number of fattening days x number of fatteners x labour price/day , other cost = number of fattening days x number of fatteners x price of other costs/pig/day; Total costs = breed cost + feed cost+ labour cost + other costs; Total revenue = total live weight in kg x price of 1 kg live weight; product cost = total costs/total live weight sold; profit = total revenuet– total cost; economic efficiency = (profit/total costs) x 100.

Data analysis method:Data was analyzed using SAS 9.1(2002). Comparing values LSM was performed using Turkey technique. The data was processed after being eliminated values outside the range X ± 3δ

CHAPTER III: RESULTS AND DISCUSSIONS

3.1 REPRODUCTIVE PERFORMANCE OF SOWS VCN21 AND VCN22 MATED WITH BOARS PIDU

3.1.1Factors affectng the reproductive performance of VCN21 and VCN22

Table 3.1Effects of some factorson reproductive performance of sows VCN21 and VCN22

Parameter / Province / Group of sow / Season / Parity
Age at the first mating / * / Ns / *
A ge at the first farrowing / * / Ns / *
Number of piglets born/litter / Ns / *** / *** / ***
Number of piglets alive/litter / Ns / *** / *** / ***
Number of weaning piglets/litter / *** / *** / *** / ***
Rate of piglets alive at weaning / Ns / Ns / *** / ***
Piglet weight at birth/piglet / Ns / *** / Ns / Ns
Piglet weight at birth/litter / Ns / *** / *** / ***
Piglet weight at weaning /piglet / * / Ns / *** / ***
Piglet weight at weaning/litter / *** / *** / *** / ***
Age of weaning piglet / Ns / Ns / *** / **
Farrowing interval / Ns / Ns / Ns / Ns
Weaning-to-estrus interval / Ns / Ns / Ns / Ns

Ghi chú: Ns: P>0,05; * : P<0,05; **: P<0,01; *** : P<0,001

Results in Table 3.1 showed that factors such as parity, season, sow group affected significantly (P<0,001) most parametters of the number and weight of piglets. The factor ‘province’ significantly affected the number of weaning pigs/litter and weaning weight/litter (P<0,001). Both farrowing interval and weaning-to-estrus interval were not affected by 4 researched factors. This result was similar to results of national and international authors (Tran Thi Dao, 2005; Pham Thi Dao, 2015; Spysl et al., 2012; Duziński et al., 2014).

3.1.2Reproductive performance of sows VCN21 and VCN22 mated with boas PiDu

Results in Table 3.2 showed that litter size of the crossbred group PiDu x VCN21 was 11.33 heads, lower than that of the crossbred group PiDu x VCN22 (12,19 heads), (P<0,05). The explaination for this result was that sows VCN22 hadinvolvedgenetic of Meishan, a breed specialising in reproduction, so it gavea higher reproductive performance than that of sows VCN21. This result was lower than the result studied by Tran Thi Dao (2005), but higher than the results reported Bui Thi Hong (2005) and Khuc Thua The (2011) who researched on sows VCN21 and VCN22 mated with boas VCN23. Our resultswas consistent with publications of Nguyen Tien Manh (2012) and Pham Thi Dao (2015) when using boars PiDu mating with F1(LxY) and F1(YxL), but higher than figures of the study reported by Vu Dinh Ton and Nguyen Cong Oanh (2010) when using Du and Pi to mate with F1(LxY) and F1(YxL).