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1.
The effect of replacing soybean crude protein (CP) with legume leaf meal (LLM) CP on feed intake, growth performance and carcass traits was studied in native female Moo Lath Lao pigs. The diets comprised one traditional diet (T) without soybean meal, one control diet (C) with soybean meal and six diets iso-nitrogenous with diet C in which soybean protein was replaced (33, 66 and 100 % of CP) with LLM CP from porcupine joint vetch (PLM) or Stylosanthes (SLM). Feed and water were offered ad libitum. Replacing soybean CP with LLM CP reduced (P?<?0.05) intake of dry matter (DMI), CP (CPI), metabolisable energy (MEI), final body weight (BW) and average daily gain (ADG), but had no effect (P?>?0.05) on feed conversion ratio (FCR). Increasing the replacement rate of soybean CP with LLM CP had a negative linear effect (P?<?0.001) on DMI, CPI, MEI, final BW and ADG, and on all carcass traits except lean meat percentage. There were no differences in dressing percentage or organ weight and length between treatments. Supplementing diet T with soybean meal resulted in higher (P?<?0.05) DMI, CPI and MEI, lower (P?<?0.05) FCR, and higher (P?<?0.05) final BW and ADG. Slaughter weight, hot carcass weight, eye muscle thickness, back fat, fat in carcass and lean meat were lower (P?<?0.05) with diet T than diet C. In conclusion, LLM from stylo and porcupine joint vetch can be used as a CP source to partially replace soybean meal CP in the diet of growing native female Moo Lath Lao pigs.  相似文献   

2.
The impact of replacing soybean crude protein (CP) with CP from ensiled taro leaves (ET) on growth performance, carcass traits, and organ weights in Landrace × Yorkshire (LY) and Moo Lath (ML) Lao pigs was studied. Twenty-four castrated male pigs, 12 of each breed, were allocated to the treatments according to a completely randomized 3?×?2 factorial (three levels of ET × two breeds) arrangement with four pigs per treatment. The pigs were kept in individual pens and were fed at 4 % dry matter of body weight for 105 days. The control diet (ET0) was formulated with soybean meal as the main CP source, and in the other two diets, soybean CP was replaced to 25 % (ET25) and 50 % (ET50), respectively, with CP from ensiled taro leaves. Calculated metabolizable energy intake decreased with increasing replacement of soybean CP in the diet, while dry matter intake (DMI), CP intake (CPI), average daily gain (ADG), and feed conversion ratio (FCR) were unaffected. Carcass weight, back fat thickness, and dressing percentage were unaffected by soybean CP replacement, while organ weights (except for spleen) increased (P?<?0.001) when soybean CP was replaced by CP from ensiled taro leaves in the diet. LY pigs had higher (P?<?0.001) DMI, CPI, and ADG and better (P?<?0.001) FCR than ML pigs. LY pigs had higher carcass weight (P?<?0.001), lower back fat thickness (P?<?0.001), and higher organ weights (P?<?0.05–0.001) than the ML pigs. In conclusion, taro leaf silage can replace up to 50 % of soybean CP in the diet of growing Lao LY and ML pigs without negative effects on performance and carcass traits.  相似文献   

3.
A total of 90 gilts were used to investigate the effects of various standard ileal digestible (SID) total sulfur amino acid (TSAA) to lysine (Lys) ratios on the performance and carcass characteristics of late finishing gilts receiving low crude protein (CP) diets supplemented with crystalline amino acids (CAA). Graded levels of crystalline methionine (Met) (0, 0.3, 0.5, 0.8 or 1.1 g/kg) were added to the basal diet to produce diets providing SID TSAA to Lys ratios of 0.48, 0.53, 0.58, 0.63 or 0.68. At the termination of the experiment, 30 gilts (one pig per pen) with an average body weight (BW) of 120 kg were killed to evaluate carcass traits. Increasing the SID TSAA to Lys ratio increased average daily gain (ADG) (linear and quadratic effect, P < 0.05), improved feed conversion ratio (FCR) (linear and quadratic effect, P < 0.05) and decreased serum urea nitrogen (SUN) concentration (linear and quadratic effect, P < 0.05) of finishing gilts. No effects were obtained for carcass traits. The optimum SID TSAA to Lys ratios to maximize ADG as well as to minimize FCR and SUN levels were 0.57, 0.58 and 0.53 using a linear‐break point model and 0.64, 0.62 and 0.61 using a quadratic model.  相似文献   

4.
The effects of yeast culture (YC) supplementation and the dietary ratio of non‐structural carbohydrate to fat (NSCFR) on growth performance, carcass traits and fatty acid profile of the longissimus dorsi (LD) muscle in lambs were determined in a 2 × 3 full factorial experiment. Thirty‐six Small‐tailed Han lambs were randomly divided into six groups with six replicates per group. The lambs were fed one of the six pelleted total mixed rations (TMRs) for 60 days after 15 adaption days. The six rations were formed by two NSCFRs (11.37 and 4.57) and three YC supplementation levels (0, 0.8 and 2.3 g/kg dietary dry matter). The average daily gain (ADG), dry matter intake (DMI) and feed conversion ratio (FCR) data of each lamb were recorded and calculated. All the lambs were slaughtered for determining carcass traits and fatty acid profile of the LD muscle. DMI was significantly increased (p < 0.05) in a quadratic fashion with 0.8 g/kg of YC supplementation. Carcass weight (CW) and dressing percentage (DP) were significantly increased (p < 0.05) in a linear fashion with 2.3 g/kg of YC supplementation. Animals fed with high‐NSCFR diet had higher (p < 0.05) contents of myristoleic acid (C14:1), pentadecanoic acid (C15:0) and cis‐10‐heptadecenoic acid (C17:1), and lower (p < 0.05) stearic acid (C18:0) content in LD muscle than those fed with low‐NSCFR diet. Moreover, ADG, growth rate (GR), backfat thickness (BFT), percentages of crude fat (CF) and crude protein (CP), SFAs, MUFAs and PUFAs in LD muscle, were significantly affected (p < 0.05) by interaction of dietary NSCFR and supplemental YC level. Overall, YC not only improved the growth performance and carcass traits of the animals but also modified the fatty acid profile of the LD muscle. Furthermore, the effects of YC supplementation may depend on dietary compositions.  相似文献   

5.
The present study examined the impact of replacing crude protein (CP) from soybean with CP from ensiled stylo (ES) on growth performance, carcass traits and organ weights in Landrace × Yorkshire (LY) and Moo Lath (ML) native Lao pigs. Twenty-four castrated male pigs, 12 of each breed, were allocated to the diet treatments according to a completely randomised 3?×?2 factorial (three ES levels × two breeds) arrangement, with four pigs per diet treatment. Pigs were kept in individual pens and fed at 4 % dry matter of body weight for 98 days. The control diet was formulated with soybean meal as the main CP source, and in the other two experimental diets, CP from soybean was replaced at 25 % (ES25) and 50 % (ES50) by CP from ES. Calculated metabolisable energy intake decreased with ES50 diet, while dry matter intake (DMI) and CP intake (CPI) were the highest in ES25 diet (P?<?0.001). Overall, average daily gain (ADG) and feed conversion ratio (FCR) were unaffected by diet treatments. Carcass weight, backfat thickness and dressing percentage were unaffected by soybean CP replacement, while the weights of lung, large intestine and stomach were higher (P?<?0.001) when 25 % of soybean CP was replaced by CP from ES. LY pigs had higher (P?<?0.001) DMI, CPI and ADG and poorer (P?<?0.001) FCR than ML pigs. LY pigs had higher carcass weight (P?<?0.001), lower backfat thickness (P?<?0.001) and higher organ weight (P?<?0.001) than ML pigs, except for small intestine weight, where there was no difference between the LY and ML pigs (P?>?0.05). In conclusion, ES can replace up to 50 % of soybean CP in the diet of growing Lao LY and ML pigs without negative effects on performance and carcass traits.  相似文献   

6.
This study assessed the effects of different nutrition levels of diets on growth performance and carcass characteristics of Hainan black goat. Twenty-four goats were divided into six diet treatments, which consisted of two levels of crude protein (CP; 15 and 17 %) and three levels of digestive energy (DE; 11.72, 12.55, and 13.39 MJ/kg). The results revealed that 17 % CP significantly (P?<?0.05) increased ADG and improved FCR compared with 15 % CP. Therefore, the CP levels of diet affected growth performance. CP and DE levels in the diet had no significant effects (P?>?0.05) on carcass characteristics of the goats. The mRNA expression levels of insulin-like growth factor 1 in muscle tissues increased with increasing CP and DE levels (P?<?0.05).  相似文献   

7.
选用61.08 kg杜×长×大三元杂交猪540头,随机分为9个处理,每处理6个重复,每重复10头猪,公、母各半。采用3×3两因素设计,日粮蛋白水平降低4个百分点,净能为9.83、10.04、10.25 MJ/kg,赖氨酸净能比为0.76、0.84、0.91 g/MJ,研究净能和赖氨酸净能比对肥育猪生长性能和胴体品质的影响。结果表明:在60~100 kg阶段,10.04 MJ/kg净能组的ADG显著高于9.83 MJ/kg组的(P<0.05);赖氨酸净能比为0.84 g/MJ组的ADG显著高于0.76 g/MJ组(P<0.05);二者互作不影响生长性能和胴体品质(P>0.05),综合评定在60~100 kg阶段,猪的低蛋白日粮净能水平和赖氨酸净能比分别为10.04 MJ/kg和0.84 g/MJ为宜。  相似文献   

8.
The objective of this experiment was to determine the effects of feeding varying levels of crude glycerine (CG) on dry matter intake (DMI), animal performance, carcass traits and rumen volatile fatty acids (VFA) concentration in meat goats. Twenty-four intact male Boer goats (23.9 ± 1.0 kg initial BW and 4–5 months of age) were randomly assigned to one of four experimental diets (n = 6) containing 30% bermudagrass hay plus 70% concentrate mix with 0, 5, 10 or 15% CG in the diet on an as-fed basis, substituted for the corn portion of the concentrate. Feed offered and refusals were monitored daily for 84 days. Goats were weighed at 28-days interval. Blood and rumen samples were collected on day 84. At the end of the 84-days feeding period, goats were harvested, and carcass characteristics measured. Feed intake, average daily gain (ADG), gain-to-feed ratio (G:F), carcass traits and VFA concentrations were analysed as a completely randomized design. The CG did not influence animal body weight (BW) changes, ADG and G:F ratio but tended to (p = 0.06) decrease DMI. Molar per cent propionic acid increased linearly (p < 0.05) with increasing CG. The acetate: propionate (A:P) ratio decreased (p < 0.05) with increasing amounts of CG in the diet. The CG addition tended to increase (p = 0.09) the longissimus muscle (LM area) in meat goats. In conclusion, CG can replace corn in diet for growing meat goats when fed up to 15% of diet, improving ruminal propionate concentration, but decreasing A:P ratio without affecting animal performance and carcass traits.  相似文献   

9.
This study investigated the effects of amino acids (AA) supplementation in low crude protein (CP) diets on growth performance and carcass characteristics in finishing gilts. One hundred and eighty gilts (59.1 ± 5.1 kg) were randomly allotted to one of five diets which consisted of a high CP (15.6%) diet or four low CP (11.6%) diets for 50 days. The low CP diets were supplemented with lysine + threonine + methionine (LCM), LCM + tryptophan (LCT), LCT + valine (LCV) or LCV + isoleucine (LCI), respectively. Gilts were housed at six pigs per pen with six pens per treatment. At the end of the 50‐day experiment, 30 gilts (one pig per pen) with average body weight (BW) of 98 kg were killed to evaluate carcass traits. The pigs fed the diet supplemented with LCV obtained the highest average daily gain (ADG), which was higher than those of pigs fed the diet supplemented with LCM (P < 0.05). Dietary supplementation with tryptophan, valine and isoleucine in low CP diets increased ADG (linear and quadratic effect, P < 0.05), serum levels of valine (quadratic effect, P < 0.05) and isoleucine (linear and quadratic effect, P < 0.05) and immunoglobulin G (IgG) and IgA (linear and quadratic effect, P < 0.05) in finishing gilts. © 2016 Japanese Society of Animal Science  相似文献   

10.
This study investigated the effects of amino acids (AA) supplementation in low‐crude protein (CP) diets on the growth performance and carcass characteristics in late‐finishing gilts. Ninety gilts (93.8 ± 5.5 kg) were randomly allotted to one of the five diets which consisted of a normal‐CP (137 g/kg) or four low‐CP (105 g/kg) diets for 28 days. The low‐CP diets were supplemented with lysine + threonine + methionine (LCM), LCM + tryptophan (LCT), LCT + valine (LCV) or LCV + isoleucine (LCI), respectively. Non‐significant difference in average daily gain (ADG) was obtained in gilts receiving the control and LCV diet, which was higher than that of gilts fed the LCM diet (p < .05). The additions of crystalline AA in the low‐CP diet resulted in the improvements in ADG (linear and quadratic effect, p < .05) and fat‐free lean gain (quadratic effect, p < .05) and influenced the valine concentration (linear and quadratic effect, p < .05) and proportion of saturated fatty acid (linear effect, p < .05) in longissimus muscle. The results indicated that the valine supplementation could further improve the performance in 94 to 118 kg gilts fed the 105 g/kg CP diet.  相似文献   

11.
A replicated factorial experiment using 183 individually fed crossbred barrows was conducted. Pigs were fed an 18.5% CP (.95% lysine) diet with 3,594 kcal of ME/kg. The effects of five genotypes (GT): 1) Hampshire (H) x (H x Duroc [D]), 2) synthetic terminal sire line, 3) (H x D) x (Landrace [L] x [Yorkshire (Y) x D]), 4) L x (Y x D), and 5) Y x L; two levels of ractopamine (RAC) treatment: 0 and 20 ppm; and three treatment weight periods (WT): 1) 59 to 100, 2) 73 to 114, and 3) 86 to 127 kg live weight on growth performance and carcass traits were evaluated. Ractopamine increased (P less than .0001) amount (FSL) and percentage (PFSL) of carcass lean standardized to 10% fat content, loin eye area (LEA), and dressing percentage (PDRES) and reduced (P less than .01) amount (DF) and percentage (PDF) of dissected fat. Magnitudes of RAC effects were smaller than those reported by other researchers. Effects of GT and WT on all growth and carcass traits were highly significant (P less than .001) except for those of WT on ADG (P less than .05) and GT on average feed intake (AFI) and backfat thickness at the last rib (BFLR; P less than .05). Genotype 3 performed better for most economically important traits than did GT 1 and 4, suggesting that heterosis existed in GT 3, which essentially was obtained by crossing GT 1 and 4. Among the three treatment periods, WT 2 had the highest ADG. As BW increased from WT 1 to 3, AFI and AFI/ADG ratio (FCR) increased and lean percentage decreased.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

12.
The aim of the article was to study the effect of different growth promoters on growth performance, carcass quality, biochemical and haematological traits and immune response of growing rabbits. A total number of 105 male growing NZW rabbits during 35–91 days of age were randomly distributed among 7 groups fed the same basal diet and submitted to different dietary treatments: the first group was unsupplemented and used as control; the other groups were supplemented respectively with bee pollen and/or propolis at 200 mg/kg BW of each and inulin and/or mannanoligosaccharides (MOS) at 35 mg/kg BW of each. Body weight gain, daily feed intake, feed conversion ratio (FCR), biochemical and haematological blood parameters, carcass characteristics, histological studies of ileum and spleen and economical efficiency were measured. Bee pollen administered alone or with propolis significantly (p < 0.01) the body weight gain and improved FCR in respect of the control group. Inulin with MOS significantly improved just FCR than the control group. Bee pollen with propolis and MOS supplemented‐groups resulted in significantly higher (7.96 and 8.41% respectively) white blood cells compared to the control group. Plasma total cholesterol was significantly higher for the MOS group in respect of the control, bee pollen, inulin and inulin with MOS supplemented‐groups. Propolis resulted in significantly higher dressed carcass percentage than the control group and higher carcass index than only bee pollen with propolis supplemented‐group. Bee pollen, in particular if in combination with propolis, could be used as a supplement in the growing rabbits during days 35–91 of age with positive effects on growth rate and feed conversion ratio.  相似文献   

13.
The objectives of this study were to characterize feed efficiency traits and to examine phenotypic correlations between performance and feeding behavior traits, and ultrasound measurements of carcass composition in growing bulls. Individual DMI and feeding behavior traits were measured in Angus bulls (n=341; initial BW=371.1+/-50.8 kg) fed a corn silage-based diet (ME=2.77 Mcal/kg of DM) for 84 d in trials 1 and 2 and for 70 d in trials 3 and 4 by using a GrowSafe feeding system. Meal duration (min/d) and meal frequency (events/d) were calculated for each bull from feeding behavior recorded by the GrowSafe system. Ultrasound measures of carcass 12th-rib fat thickness (BF) and LM area (LMA) were obtained at the start and end of each trial. Residual feed intake (RFIp) was computed from the linear regression of DMI on ADG and midtest BW(0.75) (metabolic BW, MBW), with trial, trial by ADG, and trial by midtest BW(0.75) as random effects (base model). Overall ADG, DMI, and RFIp were 1.44 (SD=0.29), 9.46 (SD=1.31), and 0.00 (SD=0.78) kg/d, respectively. Stepwise regression analysis revealed that inclusion of BW gain in BF and LMA in the base model increased R(2) (0.76 vs. 0.78) and accounted for 9% of the variation in DMI not explained by MBW and ADG (RFIp). Residual feed intake and carcass-adjusted residual feed intake (RFIc) were moderately correlated with DMI (0.60 and 0.55, respectively) and feed conversion ratio (FCR; 0.49 and 0.45, respectively), and strongly correlated with partial efficiency of growth (PEG; -0.84 and -0.78, respectively), but not with ADG or MBW. Gain in BF was weakly correlated with RFIp (0.30), FCR (-0.15), and PEG (-0.11), but not with RFIc. Gain in LMA was weakly correlated with RFIp (0.17) and FCR (-0.19), but not with PEG or RFIc. The Spearman rank correlation between RFIp and RFIc was high (0.91). Meal duration (0.41), head-down duration (0.38), and meal frequency (0.26) were correlated with RFIp and accounted for 35% of the variation in DMI not explained by MBW, ADG, and ultrasound traits (RFIc). These results suggest that adjusting residual feed intake for carcass composition will facilitate selection to reduce feed intake in cattle without affecting rate or composition of gain.  相似文献   

14.
Sorghum dried distiller's grains with solubles (S‐DDGS) are distillation extract residues from the ethanol fuel industry. In this experiment, two hundred 42‐day‐old rabbits were randomly allocated to five experimental diets containing 0 g/kg (control), 75, 150, 225 and 300 g/kg S‐DDGS. The experiment lasted for 4 weeks. No difference was found in the average daily feed intake (ADFI; p > 0.05). With increasing sorghum inclusion, the average daily gain (ADG) was linearly (p < 0.001) and quadratically (p = 0.039) reduced, while, conversely, the feed conversion ratio (FCR) linearly (p < 0.001) increased. Increasing the amount of S‐DDGS in the diet linearly decreased (p < 0.001) the apparent total tract digestibility (ATTD) of dry matter (DM), organic matter (OM), crude protein (CP) and ash. Carcass weight, carcass yield, heart and liver weights were linearly decreased by an increase in the amount of S‐DDGS added to diets (p < 0.001), but no difference was observed between the 0, 75 and 150 g/kg S‐DDGS groups (p > 0.05). Serum IL‐6, IL‐10 and SIgA linearly increased (p = 0.008) with increasing levels of S‐DDGS in the diet. Rabbits fed 0, 75 and 150 g/kg of S‐DDGS had similar IL‐6 and IL‐10 levels. Statistically significant differences in SIgA were observed between rabbits fed control diets and feed mixtures containing S‐DDGS (p < 0.01). To conclude, S‐DDGS can safely be added up to 75 g/kg, to the diet of rabbits. Increasing dietary S‐DDGS inclusion may decrease the growth performance, nutrient digestibility and carcass traits, and activate immune responses.  相似文献   

15.
Abstract

For 6 weeks, 256 female finisher pigs (initially 53.9 kg) were fed four dietary treatments of 136, 148, 159 and 168 g crude protein (CP)/kg diet. The latter diet was the 159 g CP/kg diet supplemented with dispensable amino acids, to study the effect of excess CP. Week 4 included use of metabolic cages. Feed intake, gain and feed utilisation were not significantly affected. Plasma urea (P < 0.001) and urinary nitrogen (P = 0.01) decreased linearly by lowering CP. The weight of the carcass tended to increase linearly by reducing CP, but neither nitrogen retention nor carcass meat percentage and back fat depth differed among treatments. In conclusion, the study indicated that CP could be decreased to 136 g/kg as-fed for growing pigs in the weight range 50–100 kg without negative impact on growth performance and carcass traits. Moreover, leanness was not affected by excess CP.  相似文献   

16.
Two experiments were conducted to determine the standardized ileal digestible lysine (SID Lys) requirement for weaned pigs fed with low crude protein (CP) diet. In Experiment 1, 144 pigs were fed a normal CP (20%) diet with 12.3 g/kg SID Lys and five low CP (18.5%) diets providing SID Lys levels of 9.8, 11.1, 12.3, 13.5, and 14.8 g/kg, respectively, for 28 days. Reducing dietary CP from 20% to 18.5% enhanced (p < 0.05) the growth performance. The average daily gain (ADG) and gain to feed ratio (G:F) increased (linear and quadratic; p < 0.05), serum urea nitrogen (SUN) decreased (linear and quadratic; p < 0.05) as SID Lys increased. The SID Lys levels required to maximize ADG and optimize G:F were 12.8 and 13.1 g/kg using a curvilinear plateau model, and to minimize SUN was 13.4 g/kg using a two‐slope broken‐line model, which averaged 13.1 g/kg SID Lys. In Experiment 2, 18 pigs were used in a 12‐day N balance trial and received the same diets of Experiment 1. Total N excretion was decreased when dietary CP reduced and further decreased when SID Lys increased. Collectively, 1.5% dietary CP reduction improved the growth performance and decreased the N excretion; the optimal SID Lys requirement was at 13.1 g/kg of 8–20 kg pigs fed with 18.5% CP diet.  相似文献   

17.
35～60kg生长猪可消化氨基酸需要量研究   总被引：3，自引：0，他引：3  
选用大白×长白杂种猪 6 0头 ,试验采用单因子试验设计 ,随机分为 5个处理 ,每个处理 4个重复 (圈 ) ,每个重复3头猪。 5个处理饲粮DLys水平分别为 0 .33%、0 .46 %、0 .5 8%、0 .71%和 0 .83% ,相应的CP分别为 8.6 1%、11.33%、14.0 6 %、16 .6 7%、19.2 9%。饲粮等能 (13.6 4MJDE/kg) ,等氨基酸模式 ,其氨基酸模式DLys:D -SAA :DThr:DTrp为 10 0 6 0 6 1 18。试猪始重 35 .2± 3.5 8kg ,末重 5 9.5 7± 6 .37kg。试验除考察生产性能外 ,还同时测定了氨基酸的回肠表观消化率。结果表明 :生长猪的ADG(Y1)、饲料转化率 (Y2 )均随饲粮DLys水平 (X)的增加呈显著的二次曲线变化。当DLys水平分别为 0 .6 4%和 0 .6 6 %时 ,ADG和饲料转化率分别达到极大值 (76 2 .32g)、极高值 (2 .85 )。由此可推算 ,35～6 0kg生长猪达最佳生产性能的DLys、D -SAA、DThr、DTrp和CP需要量分别为 0 .6 5 %、0 .39%、0 .40 %、0 .12 %、15 .43% ,饲粮DLys/DE之比为 0 .48g/MJ。  相似文献   

18.
The objective of this experiment was to investigate the effects of low-crude protein (CP) diets supplemented with rumen-protected lysine and methionine on growth performance, nitrogen excretion, and carcass traits in Holstein steers. Steers consumed the following diets: (1) 17.2% CP on a dry-matter basis during the early period (from 7 to 10 months of age) and 14.5% CP during the late period (from 10 to 18 months of age; CON, n = 4, initial body weight [BW] 238 kg), and (2) 14.4% CP during the early period and 11.4% CP during the late period (AA, n = 4, initial BW 243 kg). The AA diet contains rumen-protected lysine and methionine. Except for CP intake, feed intake and body weight gain were not affected by dietary CP content. Total nitrogen excretion per metabolic BW tended to be lower (p < .10) in the early period and significantly lower (p < .05) in the late period with decreasing the feed CP content. Plasma urea nitrogen concentrations were lower in AA than CON. Carcass traits and total free amino acid contents of the longissimus thoracis muscle were not affected by dietary CP content. Adding rumen-protected lysine and methionine to a low-CP diet would reduce nitrogen excretion in fattening Holstein steers without affecting productivity.  相似文献   

19.
The present study was to test if different ratios of fish meal to soy cake as protein supplements in the diet are not significantly different in effects on feed intakes and performance of growing beef cattle fed urea-treated rice straw (URTRS) as basal diet under local conditions in North Vietnam. Thirty-six male cattle of Laisind (50 % local Yellow cattle and 50 % Sindhi, both Bos indicus) at around 12 months of age with an average live weight of 124?±?12 kg at start were used in six groups of the experiment. Six diets named A, B, C, D, E, and F used in the experiment were similar in crude protein (CP) level, except for diet A with no supplementation, but different in fish meal/soy cake ratio based on CP content as follows: diet A 0/0, diet B 100/0, diet C 75/25, diet D 50/50, diet E 25/75, and diet F 0/100. Following a 4-week adaptation period, a comparison period lasted 24 weeks. The total intakes of dry matter (DM), DM from roughage, metabolizable energy (ME), and CP were 6, 7, 6, and 20 % higher in diets B–F than diet A with P values ≤0.05, 0.05, 0.05, and 0.001, respectively. The average daily gain (ADG) was 50 % higher (P?<?0.001) in diets B–F than that in diet A. Compared to diet A, diets B–F had lower feed conversion ratio (FCR)DM, FCRME, and FCRCP by 30, 20, and 30 %, respectively (all at P?<?0.001). There were no significant differences between diets B–F in the intakes, FCRs, and ADG. The apparent digestibility of CP was 12 to 24 % higher (P?<?0.001) in diets B–F than that in diet A. There was a tendency that the apparent digestibilities of DM, CP, and CF were increasing with increasing level of soy cake in this study. The ratio of fish meal to soy cake did not significantly affect feed intakes, ADG, FCR, and apparent nutrient digestibilities of the cattle. Soy cake can therefore be used to partially or fully replace fish meal as a protein supplement in the diet of growing beef cattle fed URTRS without any negative effects on animal performance.  相似文献   

20.
Two experiments were conducted to determine the effects of feeding reduced-CP, AA-supplemented diets at two ambient temperatures (Exp. 1) or three levels of dietary NE (Exp. 2) on pig performance and carcass composition. In Exp. 1, 240 mixed-sex pigs were used to test whether projected differences in heat increment associated with diet composition affect pig performance. There were 10 replications of each treatment with four pigs per pen. For the 28-d trial, average initial and final BW were 28.7 kg and 47.5 kg, respectively. Pigs were maintained in a thermoneutral (23 degrees C) or heat-stressed (33 degrees C) environment and fed a 16% CP diet, a 12% CP diet, or a 12% CP diet supplemented with crystalline Lys, Trp, and Thr (on an as-fed basis). Pigs gained at similar rates when fed the 16% CP diet or the 12% CP diet supplemented with Lys, Trp, and Thr (P > 0.10). Pigs fed the 12% CP, AA-supplemented diet had a gain:feed similar to pigs fed the 16% CP diet when housed in the 23 degrees C environment but had a lower gain:feed in the 33 degrees C environment (diet x temperature, P < 0.01). In Exp. 2, 702 gilts were allotted to six treatments with nine replicates per treatment. Average initial and final BW were 25.3 and 109.7 kg, respectively. Gilts were fed two levels of CP (high CP with minimal crystalline AA supplementation or low CP with supplementation of Lys, Trp, Thr, and Met) and three levels of NE (high, medium, or low) in a 2 x 3 factorial arrangement. A four-phase feeding program was used, with diets containing apparent digestible Lys levels of 0.96, 0.75, 0.60, and 0.48% switched at a pig BW of 41.0, 58.8, and 82.3 kg, respectively. Pigs fed the low-CP, AA-supplemented diets had rates of growth and feed intake similar to pigs fed the high-CP diets. Dietary NE interacted with CP level for gain:feed (P < 0.06). A decrease in dietary NE from the highest NE level decreased gain:feed in pigs fed the high-CP diet; however, gain:feed declined in pigs fed the low-CP, AA-supplemented diet only when dietary NE was decreased to the lowest level. There was a slight reduction in longissimus area in pigs fed the low-CP diets (P < 0.08), but other estimates of carcass muscle did not differ (P > 0.10). These data suggest that pigs fed low-CP, AA-supplemented diets have performance and carcass characteristics similar to pigs fed higher levels of CP and that alterations in dietary NE do not have a discernible effect on pig performance or carcass composition.  相似文献   

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