Feeding forage mixtures of alfalfa hay and maize stover optimizes growth performance and carcass characteristics of lambs

A feeding experiment was carried out to determine the effects of different proportions of alfalfa hay and maize stover on the growth performance and carcass characteristics of fattening lambs. Forty‐two healthy 3.5‐month‐old male Small‐tail Han lambs of 23.89 ± 0.38 kg body mass were assigned to seven groups, which were fed mixed diets composed of maize stover and alfalfa hay containing 0%, 30%, 40%, 50%, 60%, 70% or 100% maize stover on a dry matter (DM) basis. Each lamb received 1.5 kg DM of forage mixture three times daily and supplementary concentrate (0.5 kg corn per lamb per day) for 60 days. Compared with the control forage diet of maize stover only, forage intake rate and forage conversion rate on the 40% maize stover/60% alfalfa hay mixture were 30% and 5% higher, respectively. Body weight, dressing percentage and net income were 6.7 kg, 8% and 94.37 Yuan higher per lamb, respectively. Thus, feeding lambs with a forage mixture of maize stover and alfalfa hay in a ratio of 40:60 optimized the production performance, slaughter performance, and the income derived from lambs.     

Evaluation of alfalfa-corn cob associative action. I. Interactions between alfalfa hay and ruminal escape protein on growth of lambs and steers

Three trials evaluated associative action of alfalfa in ammonia (NH3)-treated corn residue diets and(or) potential ruminal degradable protein X escape protein interactions. In trial 1, 128 crossbred steers (250 kg) were fed 0 or 3% NH3-treated residue diets replaced by 0, 15, 30 or 100% of alfalfa hay. Basal diets were formulated to contain adequate metabolizable and crude protein but were nearly devoid of ruminal degradable protein. Ammonia treatment increased (P less than .02) dry matter (DM) intake of residues. Pooled across residue treatment, intake increased linearly (P less than .01) with increased level of alfalfa. A residue treatment X level of alfalfa interaction (P less than .02) for daily gain resulted because the response to level of alfalfa was linear (P less than .01) for nontreated residues and quadratic (P less than .01) for NH3-treated residues. Similar responses (P less than or equal to .07) were found for efficiency of gain, indicating that addition of 15 or 30% alfalfa promoted greater associative action for combinations involving NH3-treated vs nontreated residues. In an in vitro trial (trial 2) with the same corn cob and alfalfa diets used in trial 1, NH3 treatment increased (P less than .01) in vitro DM disappearance and rate of cell wall digestion of corn cobs. Alfalfa had no effect on rate of nontreated cob cell wall digestion, but increased (P less than .01) the rate for NH3-treated cobs.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of exogenous fibrolytic enzyme on ruminal fermentation and digestibility of alfalfa and rye-grass hay fed to lambs

This experiment was carried out to study the effect of a directly fed exogenous fibrolytic enzyme on intake and digestion of DM, OM, protein, NDF, ADF, and hemicellulose of alfalfa and ryegrass hay by sheep. Four diets were randomly assigned to four ruminally cannulated lambs using a 4 x 4 Latin square design, repeated in time, with a factorial arrangement (2 x 2) of diets: 1) alfalfa hay; 2) alfalfa hay + exogenous fibrolytic enzymes (enzyme); 3) ryegrass hay; and 4) ryegrass hay + enzyme. Lambs consumed more DM and OM from alfalfa than from ryegrass hay (P < 0.001). The ADF intake was not different between the hays, but NDF intake was lower for alfalfa (P < 0.001). For both hays, the enzyme increased intake of DM (P < 0.01), as well as OM and CP (P < 0.05); however, NDF and ADF intake were not changed. Alfalfa hay had higher apparent digestibility of DM, OM, and CP (P < 0.001), but lower digestibility for NDF, ADF, and hemicellulose. The enzyme increased apparent digestibility of CP, hemicellulose (P < 0.05), and NDF (P < 0.10) for alfalfa. Also, for both hays, the enzyme improved N balance because lambs retained more N (P < 0.05). The enzyme increased (P < 0.05) total VFA concentration (3 and 6 h) for both hays. Results from this trial indicate that directly fed exogenous fibrolytic enzymes may change ruminal fermentation, intake, and digestibility of forages with different nutritive value.     

Effects of supplementation level and particle size of alfalfa hay on growth characteristics and rumen development in dairy calves

The aim of this study was to assess the effects of particle size (PS) of alfalfa hay on growth characteristics and rumen development in dairy calves at two levels of alfalfa supplementation. Fifty newborn dairy calves (42.7 ± 2.2 kg BW) were used in a 2 × 2 factorial arrangement with the factors supplementation level (low, 8%; or high, 16% on DM basis) and PS (medium, 2.92 mm; or long, 5.04 mm as geometrical means) of alfalfa hay. In addition, a control group without alfalfa hay was used. Hence, treatments were: control (C); low level with medium PS (LM); low level with long PS (LL); high level with medium PS (HM) or high level with long PS (HL). Growth performance of alfalfa‐fed calves did not differ from control calves, but alfalfa supplementation decreased corneum thickness of the rumen wall. In alfalfa‐fed calves, post‐weaning starter intake was greater for LL calves than for LM calves. During the entire rearing period, starter intake was 26–32% higher for LL and HM calves than for LM calves. Pre‐weaning average daily gain was higher for LL and HM calves than for HL calves, but this effect was not persistent over the entire rearing period. Final body weight decreased from 86 to 79 kg when the level of long PS alfalfa hay increased from 8 to 16%, but increased from 78 to 87 kg when the level of medium PS alfalfa increased from 8 to 16%. Regardless of PS and level, morphometric characteristics of rumen wall were generally similar among alfalfa feeding groups, but corneum thickness decreased from 8.7 to 6.1 μm with greater PS at the low level. These results indicate that adequate, but not excessive, physical stimulation is required for appropriate rumen development and growth performance of dairy calves.     

压扁处理对紫花苜蓿干燥特性及干草品质的影响

为了研究紫花苜蓿干草田间调制过程中干燥特性及营养成分的变化规律,试验采用压扁和未压扁二种处理方法,在田间自然晾晒条件下,分别在刈割后和含水量为50%、40%、30%、20%时进行取样分析。结果表明：压扁处理干燥速度显著快于未压处理（P〈0.05）,水分散失均呈先快后慢的趋势;压扁处理显著降低苜蓿叶片的损失（P〈0.05）;含水量为50%、40%、30%、20%时,压扁处理苜蓿干草的粗蛋白、总消化营养物质、无氮浸出物、胡萝卜素含量均明显高于未压处理;中性洗涤纤维、酸性洗涤纤维含量明显低于未压扁处理,说明压扁处理能明显提高紫花苜蓿干燥速度,降低叶片损失,改善干草的营养品质。     

苜蓿干草长度对育肥湖羊生长性能和营养物质消化率的影响

文章旨在探讨苜蓿干草切割长度对湖羊增重性能和营养物质表观消化率的影响。试验选择60只体重和日龄相近的断奶湖羊,随机分为4组,对照组日粮中的苜蓿干草为自然长度,其余3组分别饲喂切割长度为5、15和25 mm的苜蓿干草,预饲期为10 d,正试期为90 d,在饲喂试验结束前的最后10 d开展消化试验。试验结果表明,苜蓿干草切割长度对育肥羔羊的干物质采食量具有显著影响,育肥羔羊的干物质采食量随苜蓿干草切割长度的增加而降低。苜蓿干草切割长度对育肥羔羊的平均日增重具有显著影响,以苜蓿切割长度为15 mm具有最大日增重。育肥羔羊的营养物质表观率受苜蓿干草长度的影响显著,日粮营养物质的表观消化率随苜蓿干草切割长度的增加而增加。因此,在育肥羔羊饲料配制过程中,应考虑苜蓿干草的切割长度,本试验中以苜蓿干草切割长度为15 mm具有最佳生长性能。     

Rumen fermentation characteristics, nitrogen balance and growth in lambs fed methane digester effluent

A laboratory silo trial, two lamb metabolism trials and a lamb growth trial were conducted to compare the nitrogen (N) value of swine methane digester effluent (MDE) to that of urea. Using laboratory silos (four/treatment), fermentation characteristics were measured for silages containing cracked corn, ground wheat straw and MDE added at levels of 0, 4, 8 or 12% of silage dry matter (DM). Lactic acid concentration increased linearly with up to 8% MDE addition, but then decreased (P less than .05; quadratic) with 12% MDE. Butyric acid was highest (P less than .05; linear) with 12% MDE, indicating an undesirable fermentation. In a metabolism study, DM, organic matter and N digestibilities and N balance were similar (P greater than .10) between urea and MDE, but DM digestibility was lower (P less than .05) for ensiled diets (52%) than diets fed fresh daily (59.4%). Mean ruminal volatile fatty acid, ruminal ammonia-N and plasma urea-N concentrations were similar (P greater than .10) between urea- and MDE-fed lambs. Plasma urea-N was higher (P less than .05) and ruminal isovaleric acid lower (P less than .05) in animals fed ensiled than fresh diets. In the second metabolism trial, digestibility of N was lowest (P less than .05) for MDE (51.2%) and highest for soybean meal (SBM; 71.8%), but N balance was similar among all diets.(ABSTRACT TRUNCATED AT 250 WORDS)     

Progeny test of ram lambs selected for low ultrasonic backfat thickness or high post-weaning growth rate

Ram lambs were selected from a total of 1206 lambs in 8 industry Coopworth ram breeding flocks. Eight rams were selected randomly (one from each flock), 8 were selected on the basis of a low live weight-adjusted ultrasonic backfat thickness (lean) and 8 for a high post-weaning growth rate (PW gain). Rams from a Coopworth line specially selected and bred for low ultrasonic backfat (lean selection) were also included in the progeny test in which the rams were single sire mated to 1.5 year old Coopworth ewes. Birth and weaning weights were recorded for a total of 474 female and 371 male progeny. The males (progeny of 31 sires) were slaughtered between January and April at an average hot carcass weight (HCW) of 12.56 kg and carcass growth and carcass fatness parameters recorded. The carcass composition data were analysed using the allometric equation by covariance on HCW. The adjusted mean values of carcass water content were significantly higher for the progeny of the lean selection rams (7.58 kg) than forthe other 3 sire classes (7.49, 7.46 and 7.41 for the lean, PW gain and controls respectively) indicating that they were leaner. Other indicators of carcass fatness also revealed marked differences between the sire classes. There were also marked effects of slaughter date with lambs slaughtered earlier being leaner (after adjustment for HCW) than lambs slaughtered later in the season. The results indicate that selection of sires on the basis of ultrasonic backfat thickness or post weaning live weight gain can be expected to result in the production of leaner lamb carcasses.     

日粮中添加高微量元素苜蓿青干草对杜泊羊生产性能的影响

通过在杜泊羊的日粮中添加5%～15%的高硒、高硒钴、高硒钴锌以及高硒钴锌铁4种苜蓿Medicago sativa青干草,研究对杜泊羊的采食性能、日增质量和饲料转化等方面的影响。结果表明,和添加普通苜蓿青干草相比,4种苜蓿青干草在添加量为5%～10%的情况下,均能在不同程度上提高羊日增质量,有利于饲料的转化与利用,并且饲喂安全,无副作用。其中添加15%高硒钴锌苜蓿青干草效果最好,日增质量比对照提高了59.4%,饲料转化率（30.72%）比对照提高了59.8%;在日粮中添加10%的高硒钴锌铁苜蓿青干草,效果接近前者,日增质量比对照提高了58.0%,饲料转化率（27.88%）比对照提高了44.7%。     

Carcass characteristics and meat quality of sheep fed alfalfa hay to replace Bermuda grass hay

Tropical Animal Health and Production - The objective of this study was to evaluate carcass characteristics, meat quality, and organ and viscera weight of forty male sheep, not castrated, initially...     

Impact of housing environment and management on pre-/post-weaning piglet productivity

The complex environment surrounding young pigs reared in intensive housing systems directly influences their productivity and livelihood. Much of the seminal literature utilized housing and husbandry practices that have since drastically evolved through advances in genetic potential, nutrition, health, and technology. This review focuses on the environmental interaction and responses of pigs during the first 8 wk of life, separated into pre-weaning (creep areas) and post-weaning (nursery or wean-finish) phases. Further, a perspective on instrumentation and precision technologies for animal-based (physiological and behavioral) and environmental measures documents current approaches and future possibilities. A warm microclimate for piglets during the early days of life, especially the first 12 h, is critical. While caretaker interventions can mitigate the extent of hypothermia, low birth weight remains a dominant risk factor for mortality. Post-weaning, the thermoregulation capabilities have improved, but subsequent transportation, nutritional, and social stressors enhance the requisite need for a warm, low draft environment with the proper flooring. A better understanding of the individual environmental factors that affect young pigs as well as the creation of comprehensive environment indices or improved, non-contact sensing technology is needed to better evaluate and manage piglet environments. Such enhanced understanding and evaluation of pig–environment interaction could lead to innovative environmental control and husbandry interventions to foster healthy and productive pigs.     

Retention time of macerated alfalfa hay and silage in sheep

Fresh alfalfa was mowed and conditioned mechanically at four levels: a control (rubber rolls), macerated once (a single passage through three finely corrugated rolls set at 1-mm clearance), macerated twice (two passages), and macerated thrice (three passages). Alfalfa was then field-wilted either for 45 h and conserved as chopped silage at 30% dry matter (DM) or for 94 h and stored as baled hay at 85% DM. The eight forage treatments (four mechanical conditioning levels x two conservation systems) were fed to 24 sheep (three replications per treatment) during 5 wk. At the beginning of wk 5, a 15-g sample of chromium-mordanted forage (3.5% Cr) was fed to each sheep, and feces samples were collected at 30 different times over 7 d, between 10 h and 168 h after Cr ingestion. Four models were used to estimate the passage rates, the time delay, and the mean retention time (MRT). A two-compartment time-dependent model and a multicompartment model produced the best fit (average r2 of 0.96) to represent the Cr concentration in the feces over time. When compared with alfalfa hay, alfalfa silage had a higher (P < 0.01) time-dependent turnover rate (0.0949 vs 0.0733/h), a lower (P = 0.03) time delay (9.1 vs 11 h), and a lower (P = 0.04) MRT (57.8 vs 64.4 h). Maceration did not affect significantly (P > 0.10) the time delay or the MRT. However, the MRT of macerated alfalfa hay tended to be higher than the MRT of control hay. Experimental data based on marker concentration in the feces can be used satisfactorily to assess differences in MRT between treatments, but they should be used with caution to estimate the partition of retention time within the gastrointestinal tract.     

苜蓿草粉对四川白鹅生长性能及抗氧化和免疫指标的影响

选用160只四川白鹅仔鹅,随机分为4个处理,每处理4个重复,每重复10只(公母各半),分别饲喂基础日粮(对照),添加10%(T1)、20%(T2)和30%(T3)的苜蓿草粉日粮,研究苜蓿草粉对内鹅生长性能及抗氧化和免疫功能的影响.结果表明,1)10%苜蓿草粉组体质量日平均增加量显著高于对照组(P<0.05),但料重比显...