Tài liệu Growth, reproductive performance, meat production and some solutions to enhance meat production of phanrang sheep

MINISTRY OF EDUCATION AND TRANING MINISTRY OF AGRICULTURE & RURAL DEVELOPMENT NATIONAL INSTITUTE OFANIMAL SCIENCE ============ NGO THANH VINH GROWTH, REPRODUCTIVE PERFORMANCE, MEAT PRODUCTION AND SOME SOLUTIONS TO ENHANCE MEAT PRODUCTION OF PHANRANG SHEEP Major: Animal production ID: 62 62 01 05 SUMMARY OF PhD THESIS HANOI, 2014 ii The thesis was completed at: NATIONAL INSTITUTE OF ANIMAL SCIENCE Supervisors: 1. Associate Prof. Dinh Van Binh 2. Associate. Prof. Nguyen Kim Duong Opponent 1: .......................................................................... Opponent 2: .......................................................................... Opponent 3: .......................................................................... The thesis is submitted before the Thesis Examination Committee (Institute Level) Meeting at the National Institute of Animal Science. At [Time] [Date] [Month] [Year] Thesis can be found at: 1. National Library 2. Library of National Institute of Animal Science iii SCIENTIFIC PUBLICATIONS 1. Ngo Thanh Vinh, Trinh Xuan Thanh, Đinh Van Binh, Pham Thi Thu Thuy, Le Đinh Phung and Nguyen Kim Duong. 2013. Growth and development of Phanrang sheep in Ninhthuan Province and Bavii districtHa Noi capital. Journal of Animal Science and Technology, National Intitute of Animal Science, Issue 42, July 2013, pp: 9-12. 2. Ngo Thanh Vinh, Trinh Xuan Thanh, Đinh Van Binh, NguyEn Kim DUOng.2013. Reproductive performance of Phanrang sheep in Ninhthuan and Bavi and some factors affecting reproductive performance. Journal of Animal Science and Technology, National Intitute of Animal Science, Issue 42, July 2013, pp: 21-35. 1 Introduction 1. Background and retionale Phan Rang sheep is a sheep breed, which were imported into our country hundreds of years ago and most of them are kept in Phan Rang, Ninh Thuan Province, South Central of Vietnam. Phan Rang is a hot area, the average annual temperature is 270C-290C around the year and cold season is not so common. Average rainfall in this area is very low, only 717mm/year, the highest rainfall per year is 1300mm. In recent years, the number of sheep in Vietnam has increased. Before 1975, total population was approximately 14000-15000 heads, in 2004 and 2012 these figures more than 47000 and 87743 heads, respectively (Department of Livestock, 2012). The population of sheep in 2012 was almost as two times as the population of sheep in 2004. Phan Rang sheep is characterized by a small body size, low performance, good meat quality, disease resistance. Phanrang sheep also gentle, can live well in hard conditions and eat many kinds of feed available. Therefore, Phanrang sheep still exists in this area and is widely adopted in small and medium sized farms in Ninhthuan, Binhthuan Provinces. In the North of Vietnam, most of Phanrang sheep is raised in Goat and Rabbit Research Center and small holder farms in: former Hatay, Hanam, Ninhbinh, Phutho. So far, sheep production in Northern provinces had been developing well because sheep is easily managed. It can be said that sheep production is the strengtheness of Ninhthuan province, as it adapted well to the sunny, and dry climate year-round. However, inbreeding of Phanrang sheep seemed to be high because of uncontrolled mating for many years (Le Viet Ly, 1991; Doan Duc Vu, 2006; Dinh Van Binh, 2009). Inbreeding appeared to lead to a reduction in growth, reproductive performance of sheep. over many generations therefore it gave the risk of degeneration, fecundity, growth of sheep tended to decrease (Le Viet Ly, 1991; Doan Duc Vu, 2006; Dinh Van Binh, 2009). Therefore, implementation of ram rotation from one flock to another and crossbreeding program to minimize inbreeding status and improve performance would be a viable solution. In order to have a holistic view of Phanrang sheep production and also to complete a data base of Phanrang sheep for further development of sheep farming, Phanrang sheep needs to be carrefully and fuly evaluated. For the above purposes, a study on growth, reproductive performance, meat production and some solutions to enhance meat production of Phanrang sheep was undertaken. 2 2. Objective of study - Evaluating growth, reproductive performance and meat production of Phanrang sheep in Ninhthuan province and Bavi district, Hanoi Capital. - Evaluating influence of rations on fattening performance of Phanrang sheep. - Evaluating potentials for increasing productivity of Phanrang sheep by crossbreeding of Dorper rams with Phanrang ewes. 3. Scientific and practical values of study 3.1. Scientific values of study Results of study partly contributed to a national data base on growth, reproductive performance, meat production of Phanrang sheep in Ninhthuan and Bavi and F1 crossbred sheep (Dorper x Phanrang) as well. Results of study from thesis were valuable references for students, post-graduated students, lecturers, researchers at universities and research institutions. 3.2. Practical values of study The thesis provided us with overall data on current situation of Phanrang sheep and factors affacting growth, reproduction, meat quality of Phanrang sheep. The thesis also provided us with evident that crossbreeding of Dorper rams with Phanrang ewes was an alternative to increase meat production of sheep in Ninhthuan. 4. New contribution of the thesis Although there have been some studies on sheep, this was the first time, when growth, reproduction and meat production of Phanrang sheep in Ninhthuan and Bavi and of F1 crossbred sheep (Dorper x Phanrang) as well were systematically and logically studied 5. Structure of the thesis The thesis included 153 papers, 5 chapters, 32 tables, 01 figure and 328 references, 2 scientific articles related to the thesis and appendixes. Chapter 1: LITERATURE REVIEW For more than 100 years, Phanrang sheep has been intergrated in mixed farming systems of farmers. Phanrang sheep is a meat type sheep, originated from tropical regions, where climatic condition is charaterised by a high ambient temperature. Existence of Phanrang sheep indicate that they adapt well to hot areas. Therefore, Phanrang sheep is a valuable genetic resources, which need to be conserved and developed. Growth of sheep depends considerably on age, weight, purity and sex. Each different sheep breed has difference body weight at adult. Live weight at birth is affected by litter size and weight of ewe at lambing (Gonzalez, 1972; Combellas et al., 1979). Martinez, (1983) showed that there are relationship between birth weight and development of body of sheep in next phase. According to Gatenby, (1986) body weight at birth is one of the important factors, a newborn 3 heavier sheep is not from twin lambing or is delivered by a heavier ewe. With a good feeding systems, newborn heavier sheep grow faster than a newborn sheep with a normal live weight. As a result, live weight of newborn heavier sheep is higher than that of others. Live weight at birth has a significant effect on live weight at weaning, at 6 months and at slaughter (Khan and Bhat, 1981). According to LaesFettback and Peters, (1995); Petrovice et al. (2012) sheep with higher live weight at birth has more opportunities to be survival. Growth of sheep in the first phase of breastfeeding was affected by milk yield of ewe and availability of feed resource in terms of quantity and quality. Nutrition is also an important factor affecting reproductive performance of sheep, especially before mating. Supplementation of nutrients to ewes significantly increased ovulation rate (Branca et al., 2000). There are two basic approaches to improve productivity of sheep. They are breed selection, crossbreeding of local breed with exotic breeds and improvement of environmental conditions, feeding management and quality of feeds (David and Thomas, 2006). Crossing has been applied to maximize genetic diversity of sheep. Crossing combines the desired traits in offsprings, overcome weaknesses of a particular trait in ewe or rams breeds. Chapter 2: MATERIALS AND METHODS The study results reported in this thesis come from four experiments (Exp): Exp. 1: Comparison of the growth of Phanrang sheep in Ninhthuan province and Bavi district - Hanoi Capital. Exp. 2: : Comparison of reproductive performance of Phanrang sheep in Ninhthuan province and Bavi district - Hanoi Capital and some factors affecting reproduction of Phanrang sheep. Exp. 3: Influence of rations on fattening performance of Phanrang sheep. Exp. 4: Investigation of growth and meat production of crossbred sheep (Dorper x Phanrang) in Ninhthuan. 2.2. Methods 2.2.1. Methods used for all experiments - The Exp. 1 and 2 was conducted in sheep at different ages such as at birth; 3; 6; 9 and 12 months of age. Number of animals used at different ages in Goat and Rabbit Research Centre in Bavi, Sontay and in Station for Livestock Research and Technology Transferee in Ninhthuan were: 320; 301; 276; 252; 226 and 258; 216; 201; 176, 153 sheep, respectively. Number of ewes used for our Exp. 1 and 2 in Bavi and Ninhthuan were 53 and 49, respectively. On average, ages at first mating of ewes in Bavi and Ninhthuan were 8-9 and 7.5-9 months of age. Total litters observered in Bavi and Ninhthuan was 209 (first litter: 53; second litter: 51; thirst litter 4 3: 50; fouth litter: 37; fifth and sixth litters: 18) and 215 (first litter: 49; second litter: 48; thirst litter: 45; fouth litter 4: 39; fifth and sixth litters 5;6: 34 lứa0. Number of rams used for our Exp. 1 and 2 in Bavi and Ninhthuan were 12 and 8, respectively. - Feeding standard used in all study was Feeding standard for tropical sheep of Kearl (1982) - University of Utah (USA). - Feed was sampled and analyzed for chemical compositions according to the Vietnam standards (TCVN) for animal feed. 2.2.2. Methods for four experiments. Exp. 1: Comparison of the growth of Phanrang sheep in Ninhthuan province and Bavi district - Hanoi Capital. - Sheep was managed individually based on their information such as: birth date, sire and dam. - In Ninhthuan, sheep was grazed 6-7 hours per day and supplemented with 0.15 kg concentrate feed and 0.5-1 kg grass per day. - In Bavi, sheep was grazed 2-3 hours per day and supplemented with 22.5 kg elephant grass and 0.15 kg concentrate feed per day. In the case of raining days, sheep was housed in cages, and fed 5 kg forage (3 meals per day), 2 kg concentrate (twice a day. Mineral blocks were available at any time in pens. Water was given freely via a water nipple system. Sheep both in Ninhthuan and Bavi were dewormed and vaccinated periodically. - Measurements taken: Body weight, average daily gain, body size. Exp. 2: Comparison of reproductive performance of Phanrang sheep in Ninhthuan province and Bavi district - Hanoi Capital and some factors affecting reproduction of Phanrang sheep. - Management for sheep in this experiment was similar to that in Exp.1. - Factors to be investigated in this experiment included influence of places (Bavi, Ninhthuan), parties, rams, mating and lambing seasons on reproductive performance of Phanrang sheep. - Measurements taken: all parameters of reproduction of sheep was recorded and calculated. Exp. 3: Influence of rations on fattening performance of Phanrang sheep. The Exp. 3 was conducted at Bavi Goat and Rabbit Research Center, Sơn Tay, from March to May in 2013. The experiments 3 included 2 experiments called Exp. 3.1 and Exp. 3.2. In Exp. 3.1 Fifteen male sheep, (initial weight: 15.2 to 15.7 kg, nearly 6 months of age) were used in a completely random arrangement with 3 treatments and 5 replications. Three treatments in this Exp. were three 5 rations with of 3 ratios of forage to concentrate (70:30 – treatment 1; 60:40: treatment 2 and 50:50: treatment 3). Sheep was fed individually and were adapted to the experimental rations for 10 days before data collection. Experiment 3.2 was designed similar to experiment 3. 1. However 15 male sheep (initial weight: 18.3 to 18.5 kg, nearly 9 months of age) were used. The layout of Exp. 3.1 and 3.2 was presented in Tables 2.1 and 2.2. Table 2.1 Layout of experiment. 3.1 Forage to concentrate (%) Parameters Number of animals (head) Initial age (Months) Initial weight (kg) Adaptation period (day) Experimental period (week) 70-30 5 5,7 15,7 10 8 60:40 5 5,9 15,63 10 8 50:50 5 5,9 15,23 10 8 Table 2.2: Layout of experiment 3.1 Forage to concentrate (%) Parameters 70-30 5 8,5 19,1 10 8 Number of animals (head) Initial age (Months) Initial weight (kg) Adaptation period (day) Experimental period (week) 60:40 5 8,5 19,05 10 8 50:50 5 8,3 18,93 10 8 Concentrate feed was made from different ingredients and its ingredients, chemical composition and nutritive value were presented in table 2.3. Elephant grass used in experiment was cut at 40-45 days old. The grass was finely chopped (1-3cm long) for easily mixing with concentrate feed. Before feeding to animals, chopped elephant grass and concentrate was carefully mixed according to layout of each treatments based on DM (%). Table 2.3. Ingredients, chemical composition and nutritive value of concentrate feed and elephant grass Chemical composition Ingredient of Mixing rate % and nutritive value of Value concentrate feed Corn flour Cassava chip Soybean meal Molassaes 30 30 7,5 5 concentrate feed VCK (%) CP (%) Ash (%) NDF (%) 11.99 11.51 0.735 71.36 6 Brewer Mineral , vitamins Salt 6,5 0,5 0,5 ADF (%) ME (MJ/kg DM) 41.62 9.11 Elephant grass CP (%)88.31 DM (%) (cỏ voi) ME (MJ/kg DM) 10.66 10.66 Nutritive value of rations for each treatment was presented in Table 2.4. Table 2.4. Nutritive value of rations for each treatment Forage to concentrate (%) Parametters 70-30 60:40 50:50 CP (%)34.9 DM (%) ME (MJ/DM) 11.3 11.2 11.1 9.6 9.7 9.9 Measurements taken: Feed offered and refused was individually recorded daily for calculation of feed intake and feed conversion ratio. Body weight of animals was determined at the beginning of experiment and at fours week intervals by using scale. At the finishing point of experiments (3.1 and 3.2.) three sheep for each treatment were slaughtered to determine meat production (carcass components. Meat quality parameters such as pH value of loin and semicircle muscles, meat color in semicircle muscle at 24 hours after slaughter were determined using a pH meter Star (Germany) with 5 repeatations for each sample, Minolta color meter CR-410 (Japan) with 5 repetitions. Tenderness of meat was also determined using Warner Bratzler machine 2000D (USA) with 5 repetitions. After steaming by Memmert Waterbath at temperature 75°C for 60 minutes, sample weight change after processing was determined. Exp. 4: Investigation of growth and meat production of crossbred sheep (Dorper x Phanrang) in Ninhthuan. Number of F1 crossbred sheep (Dorper x Phanrang) in Ninhthuan farm used for this experiment was 130; 110; 86; 64 and 42 heads for different ages: at birth, 3, 6, 9 and 12 months of age, respectively. Data collection was from 1/2009 to 12/2012. Mating program include 63 Phan Rang ewes and 4 Dorper rams. Sheep was grazed for 6-7 hours/day and fed in houses 0.2 kg concentrate and 0.7 to 1.2 kg grass/day. In the case of raning weather, 7 sheep were housed in barns and fed on rations containing 6 kg of forages (3 meals/day) and 0.25 concentrate kg/head/day . Measurements taken were similar to experiments 1 and 2. Meat production ans quality were determined similar to experiment 3. 2.2.3. Data analysis Data obtained in Exp.1, 2 and 4 were statistically analysed using descriptive statistics procedures with Minitab software 16.0 (2010). Means was compared using a paired test procedure also with Minitab software 16.0 (2010). Data obtained in Exp.3 were statistically analysed using GLM (General Linear Model) procedures with Minitab software 16.0 (2010). Difference in treatmen means was analysed using Tukey's method. Chapter 3: RESULT AND DISCUSSION 3.1. Live weight and body size at birth to 12 month ages of Phanrang sheep in Ninhthuan and Bavi Chest girth was the most important indicator related to the growth of animals. There was a difference in chest girth of sheep in Ninhthuan and Bavi at 3, 6, 9 and 12 months of age (P <0.05). Chest girth of sheep in Ninhthuan was longer than that of sheep in Bavi. However, live weight at different ages in two places did not differ (P>0.05). Chest girth and live weight of sheep of our result was similar to these of sheep in Philippine. Faylon, (1989) indicated that live weight of sheep could be predicted by using chest girth, cross body length and whither height of sheep. However, the most used parameter in predicting live weight of sheep was the chest girth (Benyi, 1997). Table 3.1. Live weight, chest girth, cross body length and whither height at birth – 12 months of Phanrang sheep in Ninhthuan and Bavi Age Parameter n (head) Live weight (kg) n (head) Live weight (kg) Chest girth (cm) 3 months Cross body length (cm) Whither height (cm) 6 months n (head) Live weight (kg) Chest girth (cm) At birth Bavi (Mean ± SE) 320 2.32 ± 0.016 301 12.43± 0.083 58.77a ±0.127 Ninhthuan (Mean ± SE) 258 2.41 ± 0.085 216 12.65 ± 0.098 59.27b ± 0.149 Both places (Mean ± SE) 578 2.36 ± 0.039 517 12.52 ± 0.063 58.98 ± 0.097 0.212 56.83 ±0.137 57.18 ± 0.162 56.97 ± 0.105 0.101 53.89 ± 0.117 477 17.22 ± 0.058 62.59 ± 0.111 0.008 a 54.16 ±0.152 276 17.17 ±0.767 62.17a ±0.143 b 53.53 ± 0.179 201 17.29 ± 0.089 63.17b ± 0.168 P 0.080 0.012 0.323 0.000 8 Cross body length 60.19 ±0.137 60.43 ± 0.160 60.29 ± 0.104 (cm) Whither height (cm) 56.99 ±0.141 57.36 ± 0.165 57.15 ± 0.107 n (head) 252 176 428 Live weight (kg) 22.10 ±0.122 22.47 ± 0.146 22.25 ± 0.094 Chest girth (cm) 66.79a ±0.153 68.13b ± 0.182 67.34 ± 0.121 9months Cross body length 62.99 ±0.117 63.16 ± 0.140 63.06 ± 0.090 (cm) Whither height (cm) 59.55 ±0.128 59.83 ± 0.153 59.66 ± 0.098 n (head) 226 153 379 Live weight (kg) 27.45 ±0.193 27.17 ± 0.234 27.33 ± 0.149 12 Chest girth (cm) 72.02a ±0.245 73.41b ± 0.298 72.58 ± 0.192 months Cross body length 66.43 ±0.168 66.12 ± 0.204 66.31 ± 0.130 (cm) a b Whither height (cm) 62.61 ±0.150 63.24 ± 0.182 62.86 ± 0.117 Note: a, b, means within row with different superscripts differ significantly (P<0.05). 0.256 0.089 0.054 0.000 0.335 0.159 0.361 0.000 0.233 0.008 3.2. Live weight of Phanrang sheep at different ages The result in Table 3.2 showed that live weight at birth of Phanrang sheep in Bavi and Ninhthuan was 2.32 and 2.41kg, respectively. These figures was in the range of live weight at birth of Phanrang sheep reported by Le Viet Ly et al. (1994), Đoan Đuc Vu, (2006) in Ninhthuan, Đinh Van Binh, Nguyen Kim Lin, (2007) in Bavi. Live weight of male and female lamb from 3 to 12 months of age was different. Male lambs were heavier than female lambs. A similar trend was also observed by Le Viet Ly (1994), Đinh Van Binh and Ngo Thanh Vinh, (2010). Table 3.2: Live weight of Phanrang at different ages (kg) Age 3 months 6months 9months 12 months n (head) 150 142 136 125 Bavì 12.96±0.118 Mean ± SE 2.37±0.023 23.23±0.142 29.76a±0.156 17.73±0.111 Ninh n (head) 120 105 101 91 80 Male thuan Mean ± SE 2.39±0.019 13.10±0.133 17.98±0.103 23.52±0.148 29.19b±0.177 Both n (head) 279 255 243 227 205 places Mean ± SE 2.38±0.016 13.02±0.089 17.83±0.078 23.34±0.104 29.53±0.119 P 0.489 0.426 0.126 0.172 0.019 n (head) 161 151 134 116 101 Bavì Mean ± SE 2.26±0.012 11.90a±0.108 16.57±0.081 20.79a ±0.125 24.59±0.144 Ninh n (head) 138 111 100 85 73 Female thuan Mean ± SE 2.33±0.159 12.23b±0.122 16.59±0.105 21.34b±0.187 24.96±0.196 Both n (head) 299 262 234 201 174 places Mean ± SE 2.34±0.074 12.04±0.081 16.58±0.065 21.02±0.109 24.74±0.117 P 0.250 0.045 0.887 0.010 0.120 Note: a, b, means within columns with different superscripts different significantly (P<0.05). Sex Place Parameter At birth 159 9 It seemed that live weight of male lambs at 12 months of age in Bavi was lower than that of male lambs in Ninhthuan (29.19 vs.29.76kg) (P<0.05). However, there was no deference in live weight of female lambs at 12 months of age. This result was similar to works of Dinh Van Binh and Ngo Thanh Vinh, (2010). 3.3. Average daily gain of Phanrang sheep in Bavi and Ninhthuan Daily gain of Phanrang sheep from birth to 3 months of age was the highest (male: 118.14 and female: 107.74g/ head/day, on average). From 3 months of age to 12 months of age, average daily gain of sheep gradually reduced both in male and female sheep. Daily gain of Phanrang sheep from 9 to 12 months of age was the lowest. As normal, average daily gain of male sheep was higher than that of female ones. It seemed that average daily gain (ADG) of male sheep in Bavi was significantly higher than that in Ninhthuan. The reason for this difference may be due to feeding management. The finding was similar to works reported by Hoang The Nha (2003); Dinh Van Binh and Ngo Thanh Vinh, (2010). Table 3.3a ADG of Phanrang sheep in Bavi and Ninhthuan (g/head/day) Age Sex Place Parameter From birth - 3 3-6 6- 9 9-12 months months Months months n (head) Mean ± SE n (head) Ninhthuan Male Mean ± SE n (head) Both places Mean ± SE Bavi P n (head) Bavi Mean ± SE n (head) FemaleNinhthuan Mean ± SE n (head) Both places Mean ± SE P 150 117.63± 1.26 105 118.88 ± 1.46 255 118.14 ± 0.95 0.520 151 107.08 ± 1.14 111 108.64 ± 2.57 262 107.74 ± 1.27 0.544 142 52.34 ± 1.71 101 53.86 ± 1.92 243 52.97± 1.28 0.558 134 51.92 ± 1.64 100 48.01± 1.88 234 50.25 ± 1.24 0.118 136 59.62 ± 2.0 91 59.67± 1.88 227 59.64 ± 1.41 0.987 116 44.59 ± 1.69 85 49.03± 2.39 201 46.47± 1.41 0.120 125 81.8a ± 2.68 80 72.04b ± 2.84 205 77.99 ± 2.00 0.017 101 27.74 ± 2.54 73 26.64 ± 3.07 174 27.28 ± 1.95 0.780 Note: a, b, Means within same columns with different superscripts different significantly (P<0.05). ADG of sheep of both sexes in two places followed the rule of growth of sheep. ADG increased from birth – 3 month of ages, then reduced afterward. ADG of male sheep from birth to 12 months of ages was always higher than that of female sheep. 10 Our findings were consistent with findings of several works done on tropical sheep (Abdul Wahid, 1989; El-Fadili et al., 2003; Berhanu Bela and Aynalem Haile, 2011; Lavvaf Noshari and Farahvash, 2012). Table 3.3b: Relative growth rate of Phanrang sheep in Bavi and Ninhthuan (%) Age (month) At birth -3 3-6 6- 9 9-12 months months months months n (head) 150 142 136 125 Bavì Mean ± SE 34.47 ± 0.15 7.71 ± 0.26 6.51 ± 0.21 7.09a ± 0.24 n (head) 105 101 91 80 Ninhthuan Male Mean ± SE 34.41 ± 0.16 7.86 ± 0.30 6.42 ± 0.19 6.28b ± 0.26 Both n (head) 255 243 227 205 places Mean ± SE 34.45 ± 0.11 7.77 ± 0.19 6.46 ± 0.15 6.77 ± 0.18 P 0.811 0.703 0.774 0.025 n (head) 151 134 116 101 Bavì Mean ± SE 33.95 ± 0.14 8.29 ± 0.28 5.31 ± 0.20 2.73 ± 0.25 Femal n (head) 111 100 85 73 Ninhthuan e Mean ± SE 33.89 ± 0.49 7.55 ± 0.30 5.70 ± 0.26 2.55 ± 0.30 Both n (head) 262 234 201 174 places Mean ± SE 33.93 ± 0.22 7.97 ± 0.20 5.48 ± 0.16 2.65 ± 0.19 P 0.905 0.072 0.223 0.654 Note: a, b, Means within same columns with different superscripts different significantly (P<0.05). Sex Place Parameter The result in table 3.3b showed that like ADG, relative growth rate of Phanrang sheep of both sexes in Bavi and Ninhthuan increased from birth to 3 months, then decreased afterward. Relative growth rate of Phanrang male sheep was higher than that of female sheep. Our results of live weight and relative growth rate of Phanrang male sheep were similar to these from local tropical sheep from tropical countries such as Ethiopia, Philippines, Indian, Asian (Pradhan,1989; Dvendra and Faylon, 1989; Tibbo et al., 2006; Berhanu Bela and Aynalem Haile, 2011). 3.4. Index of body structure of Phanrang sheep The result in table 3.4 showed that at 3 age months, indexes of body structure of Phan rang sheep in two places were significantly (P<0.05). BLI, BRI, BWL of male sheep in Ninhthuan at 6, 9 months of age were higher than these of male sheep in Bavi P<0,05). It seemed that grazing systems may be a factor for these differences in indexes of body structure. At 9- 12 age months, there was a difference in BRI of female sheep in Bavì and Ninhthuan (P<0,05). 11 However, BLI and BWI of sheep in Bavi and Ninhthuan were not significantly different. Table 3.4: Index of body structure of Phanrang sheep in Bavi and Ninhthuan Age (month) Index Parameter Bavì Ninhthuan Both places P Male 150 105 255 101.71a ± 0.32 103.40b ± 0.42 102.40± 0.26 0.001 3 Mean ± SE 104.24a ± 0.34 106.93b ± 0.46 105.35 ± 0.29 0.000 105.93a ± 0.33 110.49b ± 0.51 107.81 ± 0.32 0.000 127 116 243 102.69a ± 0.40 104.31b ± 0.43 103.46 ± 0.30 0.006 6 Mean ± SE 104.92 ± 0.32 105.86 ± 0.41 105.37 ± 0.26 0.067 107.64a ± 0.34 110.35b ± 0.48 108.93 0.30 0.000 96 131 227 107.07a ± 0.40 108.29b ± 0.34 107.78 ± 0.26 0.019 9 Mean ± SE 105.36 ± 0.40 105.37 ± 0.36 105.36 ± 0.27 0.098 112.72a ± 0.41 114.03b ± 0.38 113.48 ±0.28 0.023 67 138 205 108.96a ± 0.53 111.91b ± 0.40 110.95 ± 0.34 0.000 12 Mean ± SE 107.24a ± 0.47 104.87b ± 0.32 105.65 ± 0.28 0.000 116.79 ± 0.59 117.27 ± 0.37 117.11 ± 0.32 0.480 Female n (head) 151 111 262 BLI 105.45a ± 0.41 104.08b ± 0.49 104.87 ± 0.32 0.032 3 BRI Mean ± SE 105.87 ± 0.38 106.97 ± 0.48 106.34 ± 0.30 0.070 BWI 111.53 ± 0.42 111.22 ± 0.55 111.40 ± 0.33 0. 645 n (head) 134 100 234 BLI 104.08 ± 0.39 104.81 ± 0.47 104.39 ± 0.30 0.230 6 BRI Mean ± SE 106.44a ± 0.38 105.05b ± 0.53 105.85 ± 0.32 0.032 BWI 110.70 ± 0.45 110.01 ± 0.59 110.40 ± 0.36 0.340 No n (head) 116 85 201 BLI 105.05a ± 0.35 106.79b ± 0.54 105.79 ± 0.31 0.005 9 BRI Mean ± SE 106.69 ± 0.41 105.73 ± 0.50 106.28 ± 0.32 0.134 BWI 112.01 ± 0.44 112.82 ± 0.62 112.36 ± 0.37 0.274 n (head) 96 78 174 BLI 107.05a ± 0.44 108.71b ± 0.48 107.79 ± 0.33 0.012 12 BRI Mean ± SE 105.70 ± 0.46 105.12 ± 0.51 105.44 ± 0.34 0.403 BWI 113.05 ± 0.46 114.22 ± 0.62 113.58 ± 0.38 0.124 Note: BLI: Body length index, BRI: body round index,BWI:body weigh index, a, b, means within rows with different superscripts differ significantly (P<0.05). n (head) BLI BRI BWI n (head) BLI BRI BWI n (head) BLI BRI BWI n (head) BLI BRI BWI 3.5. Reproductive performance of Phanrang sheep in Bavi and Ninhthuan Results in Table 3.5 indicated that there were some differences in reproductive performance of Phanrang sheep in two places. First estrus, first mating of Phanrang ewes in Ninhthuan were earlier than these of 12 Phanrang ewes in Bavi. It also found out that post parturition estrus (day) of Phanrang ewes in Bavi was shorter than that of Phanrang ewes in Ninhthuan (P<0.05). Live weight at first mating, number of weaner/liter and weaning rate of ewes in Ninhthuan were lower than these of ewes in Bavi. Our results were similar to works reported by Đinh Van Binh and Ngo Thanh Vinh, (2010); Kumaravelu Saravana Pandian, (2012); Abegaz et al. (2002) in Indian sheep reared in South and West – North. Pelletier et al. (1987) found that pregnancy rate and litter size of ewes were influenced by several factors. The differences in season, feeding regime, herd management and day length in Ninhthuan and Bavi were main factors explaining the differences in reproductive performance of Phanrang sheep in Bavi and Ninhthuan. Table 3.5: Reproductive performance of Phanrang sheep in Bavi and Ninhthuan Indicators Ninhthuan (n = 48) (Mean ± SE) 226.6b± 4.45 271.8b± 5.92 149.6a± 0.25 451.3 ± 8.88 101.5b± 0.78 264.8 ± 1.53 18.7b ± 0.21 24.3 ± 0.30 1.22 ± 0.030 1.22 ± 0.044 1.22 ± 0.045 Bavì (n=53) (Mean± SE) 245.4a± 4.23 301.9a± 5.64 148.3b± 0.14 466.8± 8.45 113.5a± 0.74 268.5 ± 1.45 20.0a± 0.20 24.7 ± 0.29 1.2 ± 0.027 1.3 ± 0.039 1.2 ± 0.041 Both places (n=101) (Mean± SE) 236.5± 3.19 287.6± 4.33 148.9± 0.16 459.4± 6.14 107.9± 0.79 266.8± 1.06 19.4 ± 0.15 24.5 ± 0.21 1.2 ± 0.019 1.2 ± 0.028 1.2 ± 0.030 P Age of first estrus (day) 0.003 Age of first mating (day) 0.000 Gestation length time (day) 0.000 Age at first lambing (day) 0.209 Post parturition estrus (day) 0.000 Lambing intervals ( day) 0.081 Live weight at first mating (kg) 0.000 Live weight of first lambing (kg) 0.363 Litter size (head) 0.445 No of male lamb (99 heads) 0.203 No of female lamb (96 heads) 0.662 Live weight of female lamb 2.30 ± 0.027 2.30± 0.025 2.30± 0.018 0.537 (kg; 94 head) Live weight of male lamb 2.40 ± 0.029 2.40± 0.026 2.40± 0.018 0.994 (kg; 98 head) b No of weaners (head) 1.04 ± 0.029 1.2a± 0.027 1.1 ± 0.019 0.003 Weaning percentage (%) 87.15b± 1.44 96.1a± 1.30 91.5 ± 1.05 0.000 Weaning weight (kg) 12.66± .118 12.4± 0.107 12.5± 0.077 0.125 Weaning weight of male lamb (kg; 98 13.04±0.189 12.77±0.175 12.9± 0.121 0.309 heads) Weight weaning of female lamb (kg; 12.80±0.152 13.0± 0.141 12.1± 0.103 0.106 94 heads) a Litter/ year 1.4 ± 0.01 1.4a ± 0.01 1.4 ± 0.005 0.043 a, b, Note: means with same row with different superscripts different significantly (P<0.05). 3.5.1. Some factors affecting reproductive performance of Phanrang sheep in Ninhthuan and Bavi. 13 Table 3.6 showed that ram did not influence all parameters related to reproductive performance of ewes in Ninhthuan and Bavi. It was found out that post parturition heat (day) and lambing rate were significantly influences by rams used. Table 3.6: Effect of ram on reproductive performance of ewes in Ninhthuan and Bavi Parameter Ninhthuận (n=8 đực) (Mean ± SE) Post parturition heat (day) 1.2 ± 0.031.2 ± 0.020.670Lambing intervals (day) No of male lamb (head)1.2 ± 0.03 No of lamb (head) No of weaner (head) Weaning rate (%) Live weight at birth (kg) Live weight at weaning (kg) Litter/ year Bavì (n=12 đực) (Mean ± SE) Both places (n=20) (Mean ± SE) P 101.9b ± 1.45 114.2a ± 0.91 109.0 ± 1.63 0.000 269.7 ± 1.95 0.332 1.1 ± 0.02 1.1 ± 0.02 95.7 ± 0.84 2.4 ± 0.04 12.6 ± 0.08 1.4 ± 0.01 0.030 0.485 0.005 0.388 0.676 0.265 267.4 ± 2.98 1.0b ± 0.02 1.1 ± 0.02 93.1b ± 1.27 2.3 ± 0.03 12.7 ± 0.07 1.4 ± 0.02 271.4 ± 2.58 1.1a± 0.03 1.1± 0.03 97.6a ± 0.72 2.4 ± 0.07 12.6 ± 0.12 1.4 ± 0.01 Note: a, b, means with same row with different superscripts different significantly (P<0.05). 3.5.2. The effect of mating and lambing seasons on reproductive performance of Phanrang sheep Table 3.6a: Effect of mating and lambing seasons on reproductive performance of ewes in Bavi Mating season Winter Summer Parameter (n= 51) (n = 49) (Mean± SE) (Mean±SE) No of lamb (head) 1.1b ± 0.03 1.3a ± 0.05 No of male lamb (head) 0.6 ± 0.05 0.7 ± 0.06 No of female lamb (head) 1.1 ± 0.03 1.2 ± 0.04 Weaning rate (%) 96.4 ± 1.34 94.8 ± 1.61 Live weight at birth ( kg) 2.4 ± 0.02 2.3 ± 0.03 Live weight at weaning 12.5 ± 0.15 12.4 ± 0.14 (kg) Post parturition estrus 111.6b±0.95 115.5a±1.19 (day) Lambing intervals (day) 270.6± 2.32 267.6± 1.60 Litter /year 1.4 ± 0.01 1.4 ± 0.01 P 0.03 0.63 0.07 0.44 0.59 Lambing season Winter Summer (n=51) (n= 49) (Mean± SE) (Mean± SE) 1.3a ± 0.04 1.1b ± 0.03 0.6± 0.05 0.6 ± 0.06 1.2a± 0.04 1.1b ± 0.03 93.9± 1.68 97.3± 1.28 2.3± 0.03 2.4 ± 0.03 P 0.002 0.334 0.025 0.115 0.092 0.85 12.4± 0.14 12.6± 0.16 0.274 0.01 114.9± 1.04 111.9±1.21 0.060 0.30 0.43 266.7± 1.45 1.4± 0.01 271.6±2.46 1.4 ± 0.01 0.085 0.117 14 a, b, Note: means with same column with different superscripts different significantly (P<0.05). The result in table 3.6a showed that lambing season had only effects on number of lambs (P<0, 01) and Post parturition estrus (day) in Bavi (P<0,05). Table 3.6b: Effect of mating and lambing seasons on reproductive performance of ewes in Ninthuan Parameter Matting season Lambing season Dry season Rainy season P Dry season Rainy season P (n = 49) (n = 49) (n = 48) (n = 45) (Mean± SE) (Mean± SE) ((Mean± SE) Mean± SE) 1.2 ± 0.04 1.2 ± 0.04 0.599 1.2 ± 0.04 1.3 ± 0.04 0.169 No of lambs (head) No of male lamb (head ) 0.6 ± 0.06 No of female (head) 1.0 ± 0.05 Weaning rate (%) 84.9 ± 3.89 live weight at birth (head) 2.3 ± 0.03 Live weight at weaning (kg) 12.7 ± 0.14 Post parturition estrus (day) Lambing intervals ( day) Litter/year 0.6 ± 0.05 0.673 1.0 ± 0.04 0.834 84.0 ± 3.14 0.614 0.6 ± 0.05 1.0 ± 0.03 87.2 ± 2.63 0.6 ± 0.07 1.0 ± 0.06 80.9 ± 4.36 0.835 0.922 0.334 2.4 ± 0.03 0.910 2.4 ± 0.03 2.4 ± 0.03 0.951 12.5 ± 0.21 0.747 12.6 ± 0.19 12.6 ± 0.17 0.713 102.1± 1.28 102.0 ±1.73 0.998 101.2 ±1.62 103.1 ±1.44 0.312 266.4± 2.40 1.4 ± 0.01 264.3 ±2.34 1.4 ± 0.01 265.1 ±2.33 0.678 1.4 ± 0.01 0.659 264.9 ± .22 0.573 1.4 ± 0.01 0.620 The result showed that mating and lambing seasons had no significant effect of on reproductive performance of ewes in Ninthuan. 3.5.3. Effect of litter on reproductive performance of Phanrang ewe Table 3.7a: Effect of litter on reproductive performance of Phanrang ewe in Bavi n Litter size (head) 1 2 3 53 51 50 1.0a 98.1 Post Weight Weight at Lambing parturition at birth weaning interval estrus (kg) (kg) (day) (day) 2.3 11.6a 119.5a 280.5a 0.055 0.048 1.859 0.039 0.210 1.536 2.206 0.011 1.2b 1.1ab 96.1 2.4 12.3b 110.6b 265.1b 1.4a SE 0.056 0.049 1.895 0.040 0.215 1.566 2.249 0.011 Mean 1.3b 1.2ab 97.0 2.4 12.7b 113.1b 263.8b 1.4a SE 0.057 0.049 1.914 0.040 0.217 1.582 2.271 0.011 para meter lambs/l No of itter weaner (head) (head) Mean 1.1a SE Mean Weaning rate (%) Litter/ year 1.3b 15 4 37 5 and 6 18 P b ab Mean 1.3 1.2 SE 0.066 0.057 b 2.4 12.9b 109.6b 261.5b 1.4a 2.225 0.047 0.252 1.839 2.641 0.013 1.3 97.2 2.3 12.1 117.2 269.2 1.4ab 0.095 0.082 3.190 0.067 0.361 2.636 3.786 0.019 0.020 0.033 0.803 0.277 0.001 0.000 0.000 0.000 Mean 1.3 SE b 94.6 ab ab ab Note: a, b, means with same column with different superscripts different significantly (P<0.05). Results obtained from table 3.7a. showed that number of lamb/liter, number of weaner (P<0.05), weaning weight, post parturition estrus, lambing intervals and number of litter/year (P<0.01) of Phanrang ewe in Bavi were influenced by litter (from first to sixth litter). Results obtained from table 3.7b. showed that in Ninhthuan, litter (from first to sixth litter) affected significantly number lamb/litter, post parturition estrus, lambing intervals and litter/year (P<0.01). Table3.7b. Effect of litter on reproductive performance of Phanrang ewe in Ninhthuan Weigh WeightPost parturition Lambing Lamb/litter Weaner Weaning rate t Litter Parameter at weaning estrus intervals Litter/year (head) (head) (%) at birth (kg) (day (day) (kg) b a Mean 1,1 1,0 93,9 2,3 12,5 111,9 277,3a 1,3b 1 SE (n=49) 0,058 0,064 4,469 0,033 0,233 1,565 2,779 0,014 Mean 1,4a 1,1 83,3 2,3 12,7 96,7b 259,4b 1,4a 2 (n=48) SE 0,058 0,064 4,515 0,034 0,235 1,582 2,808 0,014 Mean 1,2ab 1,1 86,7 2,4 12,7 96,3b 263,1b 1,4a 3 (n=45) SE 0,060 0,066 4,663 0,035 0,243 1,633 2,900 0,015 Mean 1,2ab 1,0 80,8 2,4 12,6 97,3b 255,8b 1,4a 4 (n=39) SE 0,065 0,071 5,009 0,037 0,261 1,755 3,115 0,016 1,1b 0,9 79,4 2,3 12,6 96,3b 256,4b 1,4a 5 và 6 Mean (n=34) SE 0,069 0,076 5,365 0,040 0,280 1,879 3,336 0.017 P 0,002 0,172 0,205 0,052 0,950 0,000 0,000 0,000 Note: a, b, means with same column with different superscripts different significantly (P<0.05). Different effects of litter size on reproductive performance of Phanrang ewe in two places: Bavi and Phanrang may be due to different natural conditions, especially climatic conditions. While litter size increased from the first litter to the thirst litter, post parturition estrus (day) and lambing interval decreased from the first litter to the fifth and sixth litter. It appeared that litter/year increased from the first and second litter then was stable. Generally, reproductive performance of ewe was better from the second litter and stable from the fourth litter. 16 3.6. Influence of rations on fattening performance of Phanrang sheep from 6 to 9 months of age. As can be seen from Table 3.8, ADG of fattening sheep in treatment 3 fed on the ration with a roughage to concentrate ratio of 50:50 was the highest (181g/day), followed by ADG of sheep in treatment 2, fed on the ration with a roughage to concentrate ratio of 60:40 (150 g/day). ADG of sheep in treatment 1, fed on the ration with a roughage to concentrate ratio of 70:30 was the lowest (116g/day) (P<0,05). It seemed that at the same age, ADG of fattening sheep was significantly affected by roughage to concentrate ratios of rations. When percentage of concentrate decreased from 50 to 30 %, ADG decreased gradually. As can be seen from Table 3.9, feed intake of fattening sheep as kg DM/head/day or Kg DM/100kg live weight, increased significantly (P < 0.05) when roughage to concentrate ratios of rations increased from 70 - 30 to 60 – 40 and 50 – 50%. This trend in feed intake went parallelly with increased trend of ADG. As a result, FCR (feed conversion ratio) of fattening sheep decreased significantly (P <0.05) when concentrate ratios of rations increased from 70 - 30 to 60 – 40 and 50 – 50%. Table 3.8. Effect of rations on ADG of fattening sheep Parameter TR1 TR2 TR3 SEM P N (head) 5 5 5 Experiential length ( week) 8 8 8 Initial weight (kg) 15.7 15.63 15.23 0.2126 0.315 Weight of the first 4 weeks (kg) 18.97a 20.37b 20.50b 0.2419 0.007 a b ADG in the first 4 weeks (g/con/day) 116.78 168.92 188.21b 0.2134 0.001 Weight of the second 4 weeks (kg) 22.23a 24.07ab 25.37b 0.4308 0.006 ADG in the second 4 weeks (g/con/day) 116.42a 132.14ab 173.92b 0.3156 0.028 ADG (g/day) 116.7a 150.6b 181.0b 7.506 0.003 Note: a,b means within rows with different superscripts are significant different (P<0,05) Table 3.9: Effect of rations on feed intake and FCR of fattening sheep Parameter Feed intake (Kg DM/head/ day) Feed intake (kg DM /100 kg live weight) ME intake (MJ/head/day) FCR (Kg feed DM eaten/kg weight gain) TR1 TR2 0.83a 0.88b TR3 SEM P 0.90b 0.0093 <0.001 4.45a 4.50b 4.55c 0.0094 <0.001 2.38a 3.34b 4.22c 0.036 <0.001 a ab b 0.3741 0.017 7.28 6.03 5.07 Note: a,b means within rows with different superscripts are significant different (P<0,05) 17 Results from Table 3.10 showed that roughage to concentrate ratios of rations had some effects on dressing percentage, lean meat percentage, head, skin and wool, blood percentage. However, these effects occurred significantly (P<0.05) when roughage to concentrate ratios of rations increased from 60 – 40 to 50 – 50%. There was no difference in carcass characteristics of fattening sheep between treatment 1 and 2, where roughage to concentrate ratios of rations were 70 – 30 and 60 – 40%, respectively. Table 3.10. Carcass characteristics of fattening sheep as affected by rations Parameter n (head) Live weight (kg) Dressing percentage (%) Lean meat percentage (%) Head (%) Foot (%) Skin and wool (%) Vicera (%) Bone (%) Blood (%) TR1 3 20.53 42.30a ± 0.40 31.30a ± 0.29 6.25b ± 0.39 3.00 ± 0.59 9.19b ± 0.38 32.98 ± 0.22 12.14 ± 1.17 3.90a ± 0.59 TR2 3 23.13 42.14a ± 0.61 33.02a ± 1.26 6.82b ± 0.72 2.79 ± 0.20 10.23b ± 0.32 32.84 ± 0.64 12.08 ± 0.66 5.15b ± 0.20 TR3 3 23.37 45.74b ± 0.21 34.87b ± 1.15 4.94a ± 1.58 3.44 ± 0.22 8.48a ± 0.29 33.46 ± 0.29 12.11 ± 0.37 4.92b ± 0.53 Note: a, b means within row with different superscripts are significantly different 3.7. Influence of rations on fattening performance of Phanrang sheep from 9 to 12 months of age Table 3.11: Effect of rations on ADG of fattening sheep Parameter N (head) TR1 5 8 19.10 22.93 TR2 5 8 19.05 24.00 TR3 5 8 18.93 24.10 SEM Experiential length ( week) 0.4977 Initial weight (kg) 0.7139 Weight of the first 4 weeks (kg) ADG in the first 4 weeks a ab b 136.42 176.48 183.92 0.2965 (g/con/day) 26.43 27.72 28.40 0.7505 Weight of the second 4 weeks (kg) ADG in the second 4 weeks 125.00a 132.85ab 153.57b 0.1588 (g/con/day) 130.8a 154.9ab 169.2b 7.231 ADG (g/day) NOTE: a,b means within same rows with different superscripts differ significantly (P<0,05); P 0.968 0.466 0.023 0.222 0.016 0.014