Level and period of realimentation to assess improvement in body condition and carcass quality in cull ewes

Improvement in body condition was assessed in 40 cull ewes (>6 years), equally distributed in two groups and realimented with ad libitum roughage (gram straw) and two levels of concentrate feeding, i.e., 2.5 % (T₁) of live weight (LW) and ad libitum (T₂). Five representative animals from an initial 45 were slaughtered at the initiation of the study (0 day) and five animals from each treatment at 44, 67, and 90 days of experiment for carcass attributes. Improvement in body condition score (BCS), nutrient utilization, feed efficiency, and carcass traits were assessed at 44, 67, and 90 days. Metabolism trial of 6-day collection of feed, feces, and urine samples was conducted on five representative ewes from each group after 60 days of feeding. The level of concentrate feeding on LW gain and BCS was significant, and the duration of realimentation showed a linear improvement (P?<?0.001). The digestibility and intake of dry matter, organic matter, and crude protein was higher (P?<?0.05) in T₂. The N intake, absorption, and balance showed a similar trend. Increase (P?<?0.05) in total N, trichloroacetic acid precipitable N, and ammonia N was observed with extension of realimentation period. Blood metabolic profile also showed improvement (P?<?0.05) from an undernourished state to normal after alimentation. Animals in T₂ accumulated higher LW with minimal expenditure of metabolizable energy (73.4 vs 79.1 MJ) and higher efficiency of feed conversion during 68 to 90 days of realimentation. Linear improvement (P?<?0.01) in carcass traits (preslaughter weight, empty live weight, hot carcass weight, dressing percentage, and amount of subcutaneous and intramuscular fat) and composition of longissimus dorsi muscle was observed. Ad lib concentrate supplementation for a period of 90 days may thus be considered appropriate for achieving desired efficiency of gain and improvement in body condition of cull ewes for quality mutton production.     

Effect of feed intake restriction on reproductive performance and pregnancy rate in Egyptian buffalo heifers

The objective of the present experiment is to study the effect of feed intake restriction on the reproductive performance and pregnancy rate in Egyptian buffalo heifers. Thirty anestrus buffalo heifers were randomly divided into two equal groups. The low feed intake (LFI, n?=?15, 50 % restriction) group was fed a diet that consists of 3 kg concentrate, 1 kg wheat straw, and 3 kg fresh alfalfa, while the high feed intake (HFI, n?=?15) group was fed double the amount given to the LFI group for 4 months. All animals were weighed, transrectally examined, and visually checked for the signs of estrus, and blood samples were collected. Heifers in heat were mated with one fertile bull. The number of heifers showing estrus activity was 93.3 % in HFI vs. 20 % in LFI (P?<?0.01). Ovarian activity started earlier (P?=?0.03) in the HFI than LFI group. The weight at breeding, the diameter of the dominant follicle, number of heifers showing ovulations, number of services per conception, pregnancy rate, and overall mean of progesterone and estrogen concentrations were significantly higher (P?<?0.01) in the HFI than in the LFI group. The level of serum total protein, albumin, globulin, glucose, total cholesterol, and calcium were significantly higher (P?<?0.05) in the HFI group. Restriction of the daily feed intake to 50 % from NRC recommendations impair reproductive performance in terms of increasing the age at first service and reducing the pregnancy rate in buffalo heifers. In conclusion, feed intake could be effective in improvement of reproductive performance in buffalo heifers and further studies should be done on large scale of buffaloes in this point.     

Effect of feed restriction on intake of <Emphasis Type="Italic">Moringa oleifera</Emphasis> and <Emphasis Type="Italic">Leucaena leucocephala</Emphasis> and growth performance of rabbits

Two experiments were conducted to evaluate the effect of feed restriction on intake of Moringa oleifera (MO) or Leucaena leucocephala (LL) and growth of rabbits. In experiment one, 45 rabbits (male and female) weighing 1.18 ± 0.15 kg were used. They were randomly distributed to three feed restriction treatments (20, 30, and 40%) with 15 rabbits each (9 females and 6 males) and they were offered M. oleifera (MO) ad libitum. In experiment two, 45 growing male rabbits weighing 0.63 ± 0.113 kg were used. They were randomly assigned to 0, 20, and 30% feed restriction diets, and they have free access to L. leucocephala (LL). Intake of MO increased (P < 0.05) conforming feed restriction increased (40.6, 52.9, and 55.2 g/day of MO for 20, 30, and 40%, respectively). Daily liveweight gain and feed conversion did not differ (P > 0.05), and economic efficiency was similar among treatments. Consumption of LL increased (P < 0.05) in rabbits under the 30% restriction treatment in comparison to that of rabbits restricted 20% (46.0 and 44.4 g/day, respectively). Total feed intake (LL + feed) was highest in 20% restricted rabbits (108.0, 100.8, and 93.2 g/day for 20, 30, and 0%, respectively). Daily liveweight gain and feed conversion were not affected by feed restriction (P > 0.05). Economic efficiency improved twice in feed-restricted rabbits (2.0 and 2.3 for 20 and 30%, respectively) in contrast to that of the control 0% group (1.1). The results suggest that rabbits restricted up to 30% and supplemented with either MO or LL did not affect growth performance and reduced feed cost.     

Effect of concentrate supplementation levels on growth and slaughter characteristics of SEA and SEA × Norwegian goats under on-farm conditions

A 2?×?3 factorial experiment was carried out to evaluate the effect of goat genotypes and different concentrate levels on growth and slaughter characteristics of Small East African × Norwegian crossbred (SEA × N) and Small East African (SEA) goats. The three concentrate levels were T0 (no access to concentrate), T66 (66 % access to ad libitum concentrate allowance) and T100 (100 % access to ad libitum concentrate allowance). Twenty-four castrated goats of each genotype (18 months old with an average weight of 16.7?±?0.54 kg) were randomly allotted into T0, T66 and T100 treatments. Daily feed intake and fortnight body weight measurements were recorded for the whole 84-day experimental period, after which the animals were slaughtered. Feed intake of T100 animals was 536 g/day, which was 183 g/day higher than that of the T66 group. Supplemented goats (T66 and T100) had significantly (P?<?0.05) higher daily gain and body condition score, and better feed conversion efficiency and dressing percentage than T0 goats. The SEA goats had higher (P?<?0.05) hot carcass weight (8.2 vs. 7.9 kg) and showed better (P?<?0.05) dressing percentage than SEA × N animals. Among supplemented goats, the cost of a 1-kg gain under T66 was Tshs 213/= cheaper than T100 (US$1?≈?Tshs 1,500). It is concluded that goats should be grazed and supplemented with 353 g concentrate/day for satisfactory fattening performance and higher economic return on investment.     

Practice on improving fattening local cattle production in Vietnam by increasing crude protein level in concentrate and concentrate level

Two experiments were conducted to determine the effects of crude protein (CP) level in concentrate (experiment 1) and concentrate level (experiment 2) on feed intake, nutrient digestibility, nitrogen (N) retention, ruminal pH and NH₃-N concentration and average daily gain (ADG) of Vietnamese local fattening cattle. Animals (24 cattle, initial live weight (LW) 150.3?±?11.8 kg in experiment 1 and 145.1?±?9.8 kg in experiment 2) were allotted based on LW to one of four treatments in a randomised complete block design. In experiment 1, concentrate with four levels of CP (10, 13, 16 and 19 %) was fed at 1.5 % of LW. In experiment 2, concentrate was fed at 1.0, 1.4, 1.8 and 2.2 % of LW. In both experiments, roughage was 5 kg/day native grass and ad libitum rice straw (fresh basis). Results showed that the CP level in concentrate significantly affected dry matter (DM) intake (P?<?0.05), N retention, ADG and ruminal NH₃-N concentration (P?<?0.01), but it had no significant effect on DM, organic matter (OM) and neutral detergent fibre (NDF) digestibility (P?>?0.05), whereas CP digestibility increased (P?<?0.001) along with the CP level. DM intake, N retention and ADG increased (P?<?0.001) linearly with concentrate intake. DM and CP digestibility were not significantly affected by concentrate intake (P?>?0.05). OM digestibility and NH₃-N concentration increased linearly (P?<?0.05), whereas NDF digestibility and ruminal pH declined linearly with increased concentrate consumption (P?<?0.01). These results indicate that 16 % CP in concentrate and feeding concentrate at the rate of 2.2 % of LW are recommendable for fattening local cattle in Vietnam.     

Effect of feeding of calcium hydroxide-treated or vitamin E-supplemented cottonseed meal on plasma gossypol levels, blood parameters, and performance of Bikaneri lambs

To study the effect of feeding calcium hydroxide-treated or vitamin E-supplemented cottonseed meal (CSM) incorporated diets on plasma gossypol, blood parameters and animal performance, 24 male Bikaneri lambs of 6–7 months of age and of uniform body weight were divided into four groups of six animals each in a completely randomized design and respectively fed isonitrogenous and isocaloric concentrate mixtures containing 20 % soybean meal (CON) or 40 % raw CSM (RCSM), 40 % raw CSM supplemented with 500 IU of vitamin E per head per day (ERCSM), and 40 %, 1.5 % calcium hydroxide-treated CSM (CaCSM) along with ad libitum wheat straw throughout 510 days of experimental feeding. The lambs on all the diets grew linearly throughout the experimental period. The total weight gain, in turn the average daily gain (ADG), was not affected by dietary variations. The daily intake of dry matter, crude protein (CP), digestible crude protein (DCP) and total digestible nutrients (TDN) were found comparable among lambs of all the groups. Though total gossypol intake was similar in RCSM, ECSM and CaCSM groups, however, free gossypol intake was significantly higher (P?<?0.01) in RCSM, ECSM groups as compared to CaCSM group. Serum iron and blood hemoglobin levels were significantly (P?<?0.05) lower in RCSM group as compared to CaCSM and CON groups, and ALT activity was significantly (P?<?0.05) higher on RCSM group as compared to other groups. Plasma gossypol and osmotic fragility of erythrocytes were significantly (P?<?0.05) increased in RCSM group as compared to CaCSM and ERCSM groups. However, there was no significant difference in the concentration of other blood/serum biochemical constituents among the lambs on different groups. Based on the results, it may be concluded that feeding of 40 % CSM in the concentrate mixture of the diet in Bikaneri lambs did not have any major adverse effect in blood parameters and animal performance. Either calcium hydroxide treatment or vitamin E supplementation did not produce any major additional benefits.     

Effects of Saccharomyces cerevisiae and monensin on digestion, ruminal parameters, and balance of nitrogenous compounds of beef cattle fed diets with different starch concentrations

This study was carried out aiming to evaluate the effects of yeast or monensin supplementation on dry matter intake, nutrients digestibility, ruminal volatile fatty acids profile, ruminal pH and ammonia concentration, microbial protein synthesis, and the balance of nitrogen compounds of cattle fed high concentrate diet (80 % dry matter (DM) basis) with two different levels of starch. Eight crossbred beef steers fitted with rumen cannula were assigned to two simultaneous 4?×?4 Latin squares arranged in a 4?×?2 factorial design. Two different starch levels (23 and 38 % of DM) were assigned to each Latin square, independently. Within each Latin square, four treatments were randomly assigned to the experimental animals (control; monensin; 1-g yeast [1 g/100 kg body weight (BW)/day] treatment; and 2.5-g yeast [2.5 g/100 kg BW/day] treatment). Feed additives did not influence ruminal pH (P?>?0.05). Total ruminal volatile fatty acids (VFA) concentration was greater (P?<?0.05) in the diet with the lowest starch level. Similarly, monensin and 1-g yeast treatments resulted in greater (P?<?0.05) VFA concentration in the rumen. Monensin inclusion in the diet with the highest starch level led to a decrease (P?<?0.05) in lactate concentration in the rumen. However, acetate levels were increased (P?<?0.05) by the inclusion of 1 g of yeast in the diet with lowest starch level. Ruminal concentrations of propionate and butyrate, and ammonia-N were not influenced (P?>?0.05) by none of the additives evaluated. However, propionate concentration was greater (P?<?0.05) in the low-starch diets. Low-starch diets resulted in lower ruminal ammonia-N concentration and greater neutral detergent fiber digestibility (P?<?0.05). The excretion of urinary nitrogenous compounds, purine derivatives, synthesis of microbial protein, microbial efficiency, and balance of nitrogenous compounds were not affected by treatments evaluated (P?>?0.05). Monensin or yeast inclusion in high concentrate beef cattle diets in tropical regions as in Brazil is not justified by do not alter nutrient digestibility, nitrogen balance, and main ruminal parameters.     

Effect of inclusion of tossign (Thymus serrulatus) in concentrate mix supplementation on performance and sensory quality of meat of Menz sheep

The experiment was conducted to determine feed intake, digestibility, body weight change, carcass characteristics, and sensory quality of meat of Menz sheep supplemented with a concentrate mix and combinations of different proportions of tossign (Thymus serrulatus). Twenty yearling intact male Menz sheep were divided according to their initial body weight into five blocks of four animals in a randomized block design, and treatments were assigned randomly to each sheep within each block. The treatments were a basal diet of hay alone (T1) and supplemented with 300 g concentrate mix (T2), 200 g concentrate mix?+?100 g tossign (T3), and 100 g concentrate mix?+?200 g tossign (T4) on a dry matter basis. The results indicated that supplementation of tossign together with concentrate mix significantly increased (P?<?0.001) feed intake and improved DM and nutrient digestibility compared to the non-supplemented group. Supplementation of tossign with concentrate significantly improved (P?<?0.001) daily weight gain, feed conversion efficiency, and carcass characteristics of sheep compared to the non-supplemented group. Flavor and aroma scores of meat samples of sheep in T3 and T4 were significantly higher (P?<?0.001) than the corresponding values in T1 and T2. The scores for tenderness, juiciness, and degree of marbling of meat samples of sheep were significantly higher (P?<?0.001) in T3 and T4 compared to meat samples of sheep in T1. Inclusion of small amounts of tossign as additive in concentrate mix supplementation can improve the sensory quality of meat of Menz sheep.     

Assessment of different levels of enset (Ensete ventricosum) corm as an energy supplement in sheep fed a basal diet of Rhodes grass hay

The objective of this experiment was to evaluate the effect of feeding different levels of enset corm as a supplement to sheep fed Rhodes grass hay. Thirty local yearling rams with a mean (±SD) body weight of 16.97 (±1.13) kg were used. Six sheep were allocated to each of the five treatments in a completely randomized design. The treatments were hay ad libitum and 129 g dry matter (DM) corm (T1), 188 g DM corm (T2), 248 g DM corm (T3), 100 g DM noug (T4) cake, and hay alone (T5). One hundred grams of noug seedcake was supplemented for all treatments except T5. Total DM and organic matter (OM) intakes of sheep in T1, T2, and T3 were the highest (P?<?0.05) compared with sheep in other treatments, while sheep in T5 consumed the lowest DM and OM. The total crude protein (CP) intakes of sheep in T3 and T2 were greater (P?<?0.05) than the other treatments, while sheep in T5 consumed the lowest CP. The apparent DM and OM digestibility coefficients of T1, T2, and T3 diets were higher (P?<?0.05) compared with T5. The lowest (P?<?0.05) CP digestibility was in T5, whereas the digestibility among the supplemented groups was similar (P?>?0.05). The daily body weight gain for T1, T2, and T3 diets was greater (P?<?0.05) than that of T5. The feed conversion efficiency for T1 and T2 was higher (P?<?0.05) than T5, while T4 had an intermediate value. The highest (P?<?0.05) nitrogen retention was in sheep fed T3 diet, while the lowest was in those fed T5. It is concluded that farmers can supplement enset corm at 129 g DM/day as an alternative energy source to improve the productivity of sheep for small-scale farmers under enset-livestock production systems.     

Effect of feeding sorghum straw based complete rations with different roughage to concentrate ratio on dry matter intake,nutrient utilization,and nitrogen balance in Nellore ram lambs

An experiment was conducted by feeding sorghum straw (Sorghum bicolor) based complete rations at roughage concentrate ratio 70:30 (CR-I), 60:40 (CR-II), 50:50 (CR-III), and 40:60 (CR-IV) for 180 days to find out suitable ratio of sorghum straw in the complete ration (mash form) on nutrient utilization and nitrogen balance in Nellore ram lambs. The DMI (g/day) increased significantly (P?<?0.05) as level of concentrate increased in complete rations. No significant difference was found in digestibilities of proximate nutrients. However, CP digestibility was higher either significantly or nonsignificantly by 2.12, 5.50, and 9.36 %, respectively, in lambs fed with CR-II (P?>?0.05), CR-III (P?>?0.05), and CR-IV (P?<?0.05) rations in comparison to lambs fed with CR-I ration. Furthermore, CP digestibility was higher by 7.09 and 3.66 % in lambs fed with CR-IV ration than those fed with CR-II (P?<?0.05) and CR-III (P?>?0.05) ration. The average CWC digestibility coefficients were comparable among four rations. The N intake (g/day) was significantly (P?<?0.01) different and progressively increased by 31.46, 48.69, and 82.86 % in ram lambs fed with CR-II, CR-III, and CR-IV rations, respectively, in comparison to CR-I ration. The N balance (g/day) was higher either significantly or nonsignificantly by 34.46 (P?>?0.05), 133.46 (P?<?0.01), and 198.87 % (P?<?0.01) with CR-II, CR-III, and CR-IV rations, respectively, in comparison to CR-I ration. Based on results, it is inferred that the level of sorghum straw in complete ration had no effect on digestibility of nutrients barring crude protein in Nellore ram lambs.     

Nutritional evaluation of wheat straw treated with Crinipellis sp. in Sahiwal calves

Wheat straw was subjected to solid-state fermentation (SSF) with lignolytic white-rot fungus (WRF) Crinipellis sp. for 5 days to improve the nutritive value and digestibility. The fungal treatment caused a significant (P?<?0.05) decrease in cell wall constituents viz., neutral detergent fiber (NDF), acid detergent fiber (ADF), hemicellulose, lignin, and cellulose to the extent of 10.4, 11.2, 8.7, 8.7, and 12.1 %, respectively, with increase (P?<?0.05) in crude protein (CP) (51.6%) and ash (25.8%) contents in fungal treated wheat straw (FT-WS) than untreated wheat straw (UT-WS). Further, in vitro gas production, in vitro true dry matter digestibility and in vitro true organic matter digestibility at 48 h, metabolizable energy (ME) content, microbial biomass production, and short-chain fatty acids synthesis were significantly (P?<?0.05) higher in FT-WS. In vivo feeding trial in 10 Sahiwal calves (8–12 months) comprised of (1) control group (T1) fed with ad libitum chopped UT-WS and (2) treatment group (T2) offered with ad libitum chopped FT-WS, in addition to supplementation of groundnut cake and green berseem (Trifolium alexandrium) forage to both groups. Digestibility of nutrients for dry matter (DM), organic matter, CP, NDF, ADF, hemicellulose, cellulose, and total carbohydrates were significantly (P?<?0.05) higher in T2 compared to T1. Moreover, daily DM (P?<?0.05), digestible crude protein (P?<?0.01), and ME intakes were also higher (P?<?0.05) in group T2 with higher (P?<?0.05) nitrogen (N) retention, which resulted in significantly (P?<?0.05) higher average daily gain in body weight (135 vs. 102 g/day). It was concluded that SSF with WRF Crinipellis sp. holds potential in upgrading the nutritional worth of wheat straw for feeding growing calves.     

Effect of Brazilian red propolis administration on hematological, biochemical variables and parasitic response of Santa Inês ewes during and after flushing period

Brazilian red propolis was administered orally to Santa Inês ewes, and evaluation was made of general health and hematological, biochemical, and parasitic responses during and after flushing. Thirty mature, nonlactating, nonpregnant Santa Inês ewes (40?±?2 kg and 2.5 years old) were grazing tropical pasture (Brachiaria decumbens and Pennisetum purpureum) and, as flushing after synchronization, were supplemented with a concentrate–roughage mixture at a rate of 4 % body weight (BW). Ewes were divided according to BW and fecal egg count (FEC) into two groups (n?=?15 each): control and propolis that received propolis ethanolic extract at rates of, respectively, 0 and 3 g/ewe/day. The treatments lasted 21 days until the end of flushing period. BW and body condition score (BCS) were recorded, and blood and fecal samples were taken weekly for 8 weeks. Mean values of BW and BCS were not (P?>?0.05) affected by propolis administration. Propolis increased (P?<?0.01) total leukocytes (WBC), but no significant differences were observed for other hematological parameters. Propolis increased (P?<?0.01) total protein and globulin concentrations and decreased (P?<?0.01) triglycerides, glutamate oxaloacetate transaminase, and glutamate pyruvate transaminase. Propolis decreased (P?<?0.05) FEC. Propolis administration had good impact on ewe health and may be a promising feed additive during critical periods such as flushing.     

Intake and digestion of wethers fed with dwarf elephant grass hay with or without the inclusion of peanut hay

The aim of this study was to evaluate the effect of the inclusion of peanut (Arachis pintoi cv. Amarillo) hay in diets based on dwarf elephant grass (DEG, Pennisetum purpureum Schum cv. Kurumi) hay of different regrowth ages on forage intake and digestibility in wether lambs. The experimental treatments consisted of DEG hay with an interval of regrowth of 30 or 45 days offered as the only feed or in mixture with peanut hay (300 g/kg of total dry matter (DM)), which were tested in eight Texel?×?Suffolk crossbred wethers in a replicated 4?×?4 Latin square experiment. Both organic matter (OM) and digestible OM intakes were higher (P?<?0.05) in animals receiving the legume forage. Total apparent OM digestibility was higher (P?<?0.05) at an increased grass regrowth age. Ruminal OM digestibility increased (P?<?0.05) with legume inclusion and at a higher grass regrowth age. The nitrogen (N) intake was higher (P?<?0.05) in legume treatments and lower (P?<?0.05) as the grass regrowth age increased, but retention of N was not affected by treatments. Duodenal flow of both, non-ammonia N and microbial N, were not affected by legume inclusion and were lower (P?<?0.05) as grass regrowth age increased. The efficiency of rumen microbial protein synthesis (ERMPS) was negatively affected (P?<?0.05) by legume inclusion and was lower (P?<?0.05) as the grass regrowth age increased. Supplementation of dwarf elephant grass hay cut at the vegetative stage with peanut legume hay improves nutritional supply to wethers due to an increase in the forage intake.     

Performance of growing pigs fed diets based on by-products of maize and wheat processing

Forty-eight crossbred Landrace?×?Large white pigs with an average body weight of 8.5?±?0.4 kg and aged 2 months were used to evaluate performance and carcass characteristics of pigs fed two diets in which bran from maize or wheat was used as the energy source. A third diet based on whole maize grain was used as a control. Animals in groups of four, balanced for litter, sex and weight were allotted to dietary treatments in a completely randomised design with four replications. Data were collected on feed intake and weight gain for a period of 4 months. A digestibility trial was carried at the end of the feeding trial using two male pigs per treatment while six pigs per treatment were randomly selected for slaughter to determine carcass characteristics. Daily gain averaged 0.23, 0.31 and 0.13 kg/day, for pigs fed maize bran, wheat bran and whole maize diets, respectively. Average feed intake and final body weight were significantly (P?<?0.05) affected by diets. Digestibility of dry matter, crude fibre and calcium were higher (P?<?0.05) for pigs fed maize bran while crude protein digestibility was highest (P?<?0.05) for the pigs fed wheat bran. There were significant differences (P?<?0.05) between the diets in carcass yield, ham, head, trotters and heart weights and also for rib weight, rib eye muscle and other tissues. This study indicates that comparable performance of growing pigs fed cereal bran and full-grain diets are real.     

营养限制与补偿对蒙古育成羯羊肝脏关键酶活性的影响

本试验旨在阐明营养限制与补偿对蒙古育成羯羊肝脏关键酶活性的影响。试验选用40只平均体重为(14.72±1.10)kg的3月龄蒙古育成羯羊,随机分为对照组(CG)和双限组(RG)。试验分营养限制期(60d)和营养补偿期(90d)。限制期2组饲粮对应能氮水平为代谢能(ME):10.88(对照组)和8.62(双限组)MJ/kg;粗蛋白质(CP):15.0%(对照组)和5.7%(双限组)。补偿期各组饲喂同一能氮水平(ME:9.75 MJ/kg;CP:12.0%)的饲粮。在限制期与补偿期末分别测定蒙古育成羯羊肝脏中己糖激酶(HK)、丙酮酸激酶(PK)、乳酸脱氢酶(LDH)、果糖-1,6-二磷酸酶(FBP1)、苹果酸脱氢酶(MDH)、α-磷酸甘油脱氢酶(GAPDH)、丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)和谷氨酸脱氢酶(GLDH)的活性。结果显示:限制期结束时双限组蒙古育成羯羊肝脏中HK、ALT、AST、GLDH活性显著低于对照组(P<0.05),而PK、LDH、FBP1、MDH、GAPDH活性显著高于对照组(P<0.05);经过90d补偿后,双限组蒙古育成羯羊肝脏中HK、PK、MDH、ALT活性显著高于对照组(P<0.05),而LDH、FBP1、GAPDH、AST、GLDH活性与对照组差异不显著(P>0.05)。结果提示,限制期双限组蒙古育成羯羊糖酵解途径关键酶活性降低,糖异生途径关键酶活性升高,脂肪分解途径关键酶活性升高,这与机体在低能氮营养水平时脂肪动员加强有关,蛋白质代谢途径关键酶活性降低则表明限制期蛋白质代谢降低;补偿期双限组蒙古育成羯羊总体糖酵解、糖异生和脂肪分解途径关键酶活性基本恢复到对照组水平,而PK活性显著提高,脂肪合成和蛋白质代谢途径关键酶活性升高可能与此期较高的生长速率相关。     

Effect of rice polishing and phytase supplementation in diets on productive behavior of broilers

The addition of rice polishing (RP) and phytase enzyme to poultry diets was tested on 200 1-day-old broilers weighing 42 g. Birds were assigned to a completely random design with a 2?×?2 factorial arrangement with four treatments and five repetitions of ten birds each. The factors evaluated were RP level (0 and 15 %) and phytase (0 and 150 g/ton). The trial was divided in two phases of 21 days each (42 days total). In phase 1, no treatment effects were observed (P?>?0.10) on poultry productive behavior. In the second phase (21 to 42 days) and on the total trial (1 to 42 days), there were no effects of the treatments on weight gain or feed intake (P?>?0.10). Feed conversion was affected by RP (P?<?0.01) but not by phytase addition (P?>?0.10). In conclusion, phytase did not affect broiler production with or without RP. Addition of 15 % RP in poultry diets represents an alternative to reduce feed costs.     

Effect of replacing soybean protein with protein from ensiled stylo (Stylosanthes guianensis (Aubl.) Sw. var. guianensis) on growth performance, carcass traits and organ weights of exotic (Landrace × Yorkshire) and native (Moo Lath) Lao pigs

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.     

Strategic supplementation of cassava top silage to enhance rumen fermentation and milk production in lactating dairy cows in the tropics

High-quality protein roughage is an important feed for productive ruminants. This study examined the effects of strategic feeding of lactating cows with cassava (Manihot esculenta) top silage (CTS) on rumen fermentation, feed intake, milk yield, and quality. Four early lactating crossbred dairy cows (75% Holstein-Friesian and 25% Thai) with body weight (BW) 410?±?30 kg and milk yield 12?±?2 kg/day were randomly allotted in a 4?×?4 Latin square design to four different supplementation levels of CTS namely, 0, 0.75, 1.50, and 2.25 kg/day of dry matter (DM). Strategic supplementation of CTS significantly affected ruminal fermentation end-products, especially increased propionate production, decreased protozoal population and suppressed methane production (P?<?0.05). Increasing the CTS supplementation level substantially enhanced milk yield and the 3.5% FCM from 12.7 to 14.0 kg/day and from 14.6 to 17.2 kg/day (P?<?0.05) for non-supplemented group and for the 2.25 kg/day supplemented group, respectively. We conclude that high-quality protein roughage significantly enhances rumen fermentation end-products, milk yield, and quality in dairy cows.     

Comparison of silage and hay of dwarf Napier grass (<Emphasis Type="Italic">Pennisetum purpureum</Emphasis>) fed to Thai native beef bulls

Both quantity and quality of forages are important in dry season feeding. Eight Thai native beef bulls were arranged in a Completely randomized design to evaluate dwarf Napier namely Sweet grass (Pennisetum purpureum cv. Mahasarakham) preserved as silage or hay on feed intake, digestibility, and rumen fermentation. The animals were fed with forage ad libitum supplemented with concentrate mixture at 1.0% of BW for 21 days; data were collected during the last 7 days. The results showed that there were differences (P?<?0.05) between treatments in dry matter (DM) intake, DM digestibility, and ruminal pH, in which hay feeding gave enhanced feed intake and more favorable ruminal pH. Nevertheless, mean ruminal ammonia nitrogen, total volatile fatty acids (TVFAs), proportion of VFAs, bacterial and protozoal population, and blood urea nitrogen were similar (P?>?0.05) in animals fed silage and hay. Sweet grass is better preserved as hay rather than silage.     

Cecotrophy behavior and use of urea as non-protein nitrogen (NPN) source for capybara (Hydrochoerus hydrochaeris)

Fifteen female adult capybaras, with initial average body weight (BW) of 32.7 (±?5.8) kg, were kept in individual pens to evaluate effect of supplementation of concentrate feed and its supply time on cecotrophy behavior frequency. The animals were allocated in a completely randomized design, with five animals per treatment, receiving three diets: grass only, grass and grain corn offered in a single meal, and grass and grain corn offered in two daily meals; all cecotrophy acts were recorded. Later, in a second experiment, five capybaras received five levels of urea in their diet: 0, 10, 20, 30, and 40 g urea/100 kg BW, replacing soybean meal as true protein source, in a 5?×?5 Latin square design. The animals were weighed and their blood was collected every 2 weeks. The frequency of cecotrophy (Ps?<?0.05) was higher when the capybaras were fed grass only (0.5?±?0.07 acts/h) than when they received grass and corn in a single meal (0.3?±?0.05 acts/h) and grass and corn supplied in separate meals (0.1?±?0.03 acts/h). With increased urea in their diet, the capybaras showed initial signs of chronic intoxication, together with increments in serum urea (r?=?0.87, P?<?0.05) and a decreasing trend in daily weight gain (r?=??0.38, P?=?0.06). Therefore, when including concentrate feeds in capybara diet, these must be mixed with roughage in a single meal to avoid high decrease in the frequency of cecotrophy behavior and increase in dry matter intake. The replacement of soybean meal with urea in capybara diet is not recommended.