Influence of different substitutions of ground-to-whole sorghum grain in high-concentrate diets on weight gain,Longissimus dorsi area and subcutaneous fat of growing goats

The effect of different proportions of ground-to-whole sorghum grain on weight gain, Longissimus dorsi area (LDA) and subcutaneous fat (SF) was evaluated in 20 crossbred (75% Alpine and 25% Spanish) female kid goats, 75 d of age (12.9?±?1.8?kg BW [body weight]) fed a diet (14% CP [crude protein], 2.57 Mcal/kg ME [metabolizable energy]) in which whole sorghum grain (WSG) substituted for 0%, 25% and 50% of ground sorghum grain for treatments T1 (n?=?7), T2 (n?=?7) and T3 (n?=?6), respectively. At the end of the 122-d feeding trial, goats were evaluated using ultrasound for LDA and SF. There were no differences (P?>?.05) among treatments in average daily gain (183, 183 and 190?g/d) and LDA (14.02, 13.70 and 14.70?cm²). SF decreased (linear effect; P?=?.05) with an increase in dietary WSG. In conclusion, feedlot goats exhibited adequate growth performance using diets with up to 50% WSG, without negative effect on LDA, although SF decreased with WSG increase.     

Effect of ractopamine hydrochloride on environmental gas emissions,growth performance,and carcass characteristics in feedlot steers

With a growing global population and increased environmental concerns around animal agriculture, it is essential to humanely maximize animal performance and reduce environmental emissions. This study aims to determine the efficacy of feeding ractopamine hydrochloride (RAC), an orally active, β ₁-adrenergic agonist (β₁AA), to feedlot steers in the last 42 d of finishing to reduce ammonia (NH₃) emissions and improve animal performance. A randomized complete block design was used to allocate 112 Angus and crossbred Angus steers (initial body weight [BW] = 566.0 ± 10.4 kg) to 8 cattle pen enclosures. Pens (n = 4 per treatment, 14 steers per pen, and 56 steers per treatment) were randomly assigned to one of two treatments: 1) CON; finishing ration containing no RAC, 2) RAC; finishing ration containing 27.3 g/907 kg dry matter (DM) basis RAC. Steers were weighed on day −1 and 0 before treatment and day 14, 28, and 42 during treatment. Treatment rations were mixed and delivered daily by masked personnel. Measured emissions included NH₃, nitrous oxide (N₂O), methane (CH₄), hydrogen sulfide (H₂S), and carbon dioxide (CO₂). The primary response variables assessed were emissions standardized by live weight (LW) and hot carcass weight (HCW). Steers were harvested on day 43 and carcass data were collected on day 43 and 44. Steers fed RAC reduced NH₃ emissions by 17.21% from day 0 to 28 (P = 0.032) and tended to reduce NH₃ from day 0 to 42 by 11.07% (P = 0.070) vs. CON. When standardized for LW, NH₃ was reduced by 23.88% from day 0 to 14 (P = 0.018), 17.80% from day 0 to 28 (P = 0.006), and 12.50% for day 0 to 42 (P = 0.027) in steers fed RAC vs. CON. Steers fed RAC had 14.05% (P = 0.013) lower cumulative NH₃ emissions when standardized by HCW vs. CON. Feeding RAC to Steers reduced H₂S by 29.49% from day 0 to 14 (P = 0.009) and tended to reduce H₂S over day 0 to 28 by 11.14% (P = 0.086) vs. CON. When H₂S emissions were standardized for LW, RAC fed steers had a 28.81% reduction from day 0 to 14 (P = 0.008) vs. CON. From day 0 to 42 the RAC fed steers tended to have a 0.24 kg/d greater average daily gain (ADG) (P = 0.066) and tended to eat 4.27% less (P = 0.069) on a DM basis vs. CON. The RAC fed steers had a 19.95% greater gain to feed ratio (G:F) compared to CON (P = 0.012). Steers fed RAC had an average of 12.52 kg greater HCW (P = 0.006) and an increase of 1.93 percentage units in dressing percent (DP) (P = 0.004) vs. CON. Ractopamine is an effective medicated feed additive for reducing NH₃ and improving end product performance through HCW yields.     

The influence of extended supplementation of quebracho extract to beef steers consuming a hay diet on digestion,ruminal, and blood parameters

The addition of natural plant secondary compounds to ruminant feed has been extensively studied because of their ability to modify digestive and metabolic functions, resulting in a potential reduction in greenhouse gas emissions, among other benefits. Condensed tannin (CT) supplementation may alter ruminal fermentation and mitigate methane (CH₄) emissions. This study’s objective was to determine the effect of quebracho CT extract [QT; Schinopsis quebracho-colorado (Schltdl.) F.A. Barkley & T. Meyer] within a roughage-based diet on ruminal digestibility and kinetic parameters by using the in situ and in vitro gas production techniques, in addition to blood urea nitrogen (BUN) and ruminal (volatile fatty acid [VFA], NH₃-N, and protozoa count) parameters. Twenty rumen-cannulated steers were randomly assigned to four dietary treatments: QT at 0%, 1%, 2%, and 3% of dry matter (DM; QT0: 0% CT, QT1: 0.70% CT, QT2: 1.41% CT, and QT3: 2.13% CT). The in situ DM digestibility increased linearly (P = 0.048) as QT inclusion increased, whereas in situ neutral detergent fiber digestibility (NDFD) was not altered among treatments (P = 0.980). Neither total VFA concentration nor acetate-to-propionate ratio differed among dietary treatments (P = 0.470 and P = 0.873, respectively). However, QT3 had lower isovalerate and isobutyrate concentrations compared with QT0 (P ≤ 0.025). Ruminal NH₃ and BUN tended to decline (P ≤ 0.075) in a linear fashion as QT inclusion increased, suggesting decreased deamination of feed protein. Ruminal protozoa count was reduced in quadratic fashion (P = 0.005) as QT inclusion increased, where QT1 and QT2 were lower compared with QT0 and QT3. Urinary N excretion tended to reduce in a linear fashion (P = 0.080) as QT increased. There was a treatment (TRT) × Day interaction for in vitro total gas production and fractional rate of gas production (P = 0.013 and P = 0.007, respectively), and in vitro NDFD tended to be greater for QT treatments compared with no QT inclusion (P = 0.077). There was a TRT × Day interaction (P = 0.001) on CH₄ production, with QT3 having less CH₄ production relative to QT0 on day 0 and QT2 on days 7 and 28. Feeding QT up to 3% of the dietary DM in a roughage-based diet did not sacrifice the overall DM digestibility and ruminal parameters over time. Still, it is unclear why QT2 did not follow the same pattern as in vitro gas parameters. Detailed evaluations of amino acid degradation might be required to fully define CT influences on ruminal fermentation parameters and CH₄ production.     

玉米和玉米青贮日粮添加赖氨酸对肉牛生长性能及血液生化指标的影响

选择56头利木赞F_1杂交公牛,研究赖氨酸添加水平对肉牛生长性能及血液生化指标的影响。试验动物随机分为4组,每组14头,分别饲喂添加不同梯度的过瘤胃赖氨酸(0、5、10 15 g/d和15 g/d)日粮。结果表明:日粮中赖氨酸添加量对肉牛的采食量没有显著影响(P>0.05),对日增重(P=0.036)和饲料转化率(P=0.030)具有二次曲线影响,其中赖氨酸的添加量为10 g/d时,肉牛日增重最大,饲料转化率最高。随着赖氨酸添加量的增加,血液尿素氮(P=0.014)和胰岛素(P=0.022)呈二次曲线变化,但对其他血液生化指标没有影响。本试验结果表明,对于以玉米和玉米青贮为基础日粮的肉牛来说,10 g/d为过瘤胃赖氨酸的最适添加量。     

Influence of wet fixation, staining techniques, and storage time on bull sperm morphology

The influence on sperm morphology of different methods for preparation of semen and of storage in a fixative solution was examined in 27 beef bulls subjected to a regular breeding health examination. Sperm head morphology under light microscopy did not differ between smears of fresh semen stained with carbol-fuchsin-eosin (Williams staining) or Nigrosin-Eosin. Nor was there any difference between samples stained immediately after collection and those stained after 1 month of storage at + 4 degrees C in buffered formal-saline solution. Formol-saline fixed spermatozoa examined in wet preparations under phase contrast microscopy had a higher prevalence of acrosome defects and cytoplasmic droplets than stained smears of fresh semen under light microscopy. One month of storage in formol-saline did not affect the prevalence of acrosome defects or cytoplasmic droplets. There was no influence of fixation method (wet or dry), staining, examination technique, or storage time on midpiece or sperm tail morphology. The affinity of spermatozoa to eosin at staining with Nigrosin-Eosin ("live and dead count") did not differ between fresh semen and spermatozoa that had been stored in formol-saline for 1 month. It is concluded that bull semen can be stored for at least 1 month at + 4 degrees C in buffered formal-saline without major changes in sperm morphology. Furthermore, examination of wet preparations of fixed spermatozoa under phase contrast microscope is likely to yield the most accurate results for morphological characteristics like acrosome morphology and cytoplasmic droplets.     

Effect of pineapple stem starch feeding on rumen microbial fermentation,blood lipid profile,and growth performance of fattening cattle

Pineapple stem starch (PS) was evaluated for its suitability as a new starch source in concentrate for fattening cattle, based on the growth performance, blood profile, and rumen parameters of 36 steers in a 206‐day feeding study. PS was formulated as a 40% concentrate and fed with forage in comparison with ground corn (GC) and ground cassava (CA) formulated at the same level. PS feeding improved weight gain and feed conversion ratio without affecting feed intake. PS did not obviously influence blood lipid profiles throughout the experiment. Ruminal concentration of total short‐chain fatty acids (SCFA) increased with PS without affecting SCFA composition throughout the feeding study. Rumen amylolytic group, especially Ruminococcus bromii, was dominant in the rumen microbial community, and showed increased abundance by PS feeding throughout the experiment. These results clearly indicate the potential of PS as a useful starch source for fattening cattle in terms of rumen fermentation and growth performance.     

Effects of maize grain and lucerne particle size on ruminal fermentation, digestibility and performance of cows in midlactation

This study evaluated the effects of, and interactions between, maize grain particle size (MPS) and lucerne particle size (LPS) on dry matter intake, milk production, milk composition, ruminal fermentation, microbial yield, chewing activity and nutrient digestibility in midlactation cows. Four multiparous Holstein cows with ruminal cannulas were assigned randomly to a 4 x 4 Latin square design, averaged 595 kg (SD = 52) of body weight and 121 days in milk (SD = 21) at the start of the experiment. Experimental periods were 21 days in length (14 days of treatment adaptation and 7 days of data collection). All diets were fed as total mixed ration and were formulated to meet or exceed the requirements of a 600 kg multiparous cow producing 20 kg milk/day with 4.0% fat. The ratio of concentrate to forage was 39:61 (dry matter basis). Treatments were arranged in a 2 x 2 factorial design; two levels of LPS (2.54 and 6.22 mm) were combined with concentrates based on either ground maize grain (711 mum) or cracked maize grain (1755 mum). Maize grain and LPS did not affect milk production and milk fat percentage. Milk protein percentage increased when MPS was decreased (p = 0.04). Milk urea nitrogen was lower for cows fed ground maize grain compared with cracked maize grain (118-134 mg/l, p = 0.05). Estimated microbial N supply increased 41.9 g/day for ground maize grain compared with cracked maize grain. Cows fed long lucerne (LL) hay spent more time ruminating compared with cows fed short lucerne (SL) hay ranging from 293 to 336 min/day (p < 0.001). Total time spent chewing by cows increased from 505 to 574 min/day (p = 0.002) for SL and LL respectively. Based on the results from this study, midlactation cows can be fed diets that contain ground maize grain and SL hay without leading to negative effects on ruminal pH and nutrient digestibility.     

Feeding corn distillers grains as an energy source to gestating and lactating beef heifers: Impact of excess protein on feedlot performance,glucose tolerance,carcass characteristics and Longissimus muscle fatty acid profile of steer progeny

This study was conducted to determine the impact of dried distiller's grain with solubles (DDGS) from 192 days of gestation through 118 days of lactation on feedlot performance, carcass characteristics, Longissimus muscle (LM) fatty acids and glucose tolerance of male progeny (n = 36). Angus‐Simmental heifer dams were fed diets that contained either DDGS (DG) or not (CON) formulated to provide similar daily net energy for gain but differing crude protein. In the feedlot, male progeny were fed a diet devoid of DDGS. An intravenous glucose tolerance test (IVGTT) was performed on a subset of 20 steers prior to harvest. Steers were harvested at a common 12th rib fat depth. Data were analyzed with the GLIMMIX and MIXED procedures of SAS. Performance (P ≥ 0.11) and glucose and insulin concentrations during IVGTT (P ≥ 0.24) did not differ between treatments. Dressing percentage tended to be greater (P = 0.09) in DG than CON progeny, but all other carcass characteristics did not differ (P ≥ 0.18). Progeny from DG dams had greater LM 16:2, 18:0, and 20:1 n‐9 concentrations than progeny from CON dams (P ≤ 0.02). In conclusion, DDGS are a viable option for gestating and lactating beef cows.     

全株青贮玉米对西门塔尔杂交牛生产性能、表观消化率及血液生化指标的影响

选择体重350 kg左右健康的西门塔尔杂交公牛45头随机分为3组,分别饲喂3种不同日粮,其中试验Ⅰ组(精料+玉米秸秆黄贮)、试验Ⅱ组(精料+全株青贮玉米)和试验Ⅲ组(精料+添加剂全株青贮玉米),试验期140 d。结果表明,试验Ⅲ组的日增重极显著地高于试验Ⅰ组(P<0.01)和试验Ⅱ组(P<0.01),分别比试验Ⅰ组、试验Ⅱ组高出90.35%、24.00%。试验Ⅰ组干物质采食量极显著高于试验Ⅱ组(P<0.01)和Ⅲ组(P<0.01),试验Ⅱ组和试验Ⅲ组的干物质采食量无显著差异。试验Ⅲ组和试验Ⅱ组料重比极显著低于Ⅰ组(P<0.01)。试验Ⅲ组和试验Ⅱ组的粗蛋白的表观消化率显著高于试验Ⅰ组(P<0.05),试验Ⅲ组粗蛋白表观消化率极显著高于试验Ⅰ组(P<0.01);中性洗涤纤维和酸性洗涤纤维的表观消化率Ⅲ组显著高于试验Ⅰ组(P<0.05)。肉牛血清中游离脂肪酸、瘦素的含量试验Ⅰ组显著高于Ⅱ组和Ⅲ组(P<0.05)。肉牛血清中胰岛素样生长因子Ⅰ浓度试验Ⅱ组、试验Ⅲ组显著高于Ⅰ组(P<0.05),试验Ⅱ组与试验Ⅲ组差异显著(P<0.05)。试验Ⅲ组的头均日收益比试验Ⅰ组、试验Ⅱ组分别高22.21和9.27元。综上所述,添加剂全株青贮玉米的育肥效果和经济效益最好。     

Interactive effect of corn particle size and insoluble fiber source on performance,nutrient utilization and intestine morphology in broilers fed pelleted diets

The effects of corn particle size and dietary fibre on the performance, coefficient of apparent ileal digestibility (CAID) and intestinal characteristics in broiler starters fed pelleted diets were studied. The experiment included 10 treatments arranged as a 2 × 5 factorial with two corn particle sizes (GMD of 1071 [CGC] vs. 534 [FGC]) and five diets that consisted in a low-fibre diet and four extra diets resulting from the inclusion of insoluble fibre sources (10 g/kg of lignocellulose (LC), and 30 g/kg of oat hulls; OH, rice hulls; RH, and sunflower hulls; SFH). In coarse grinding, all-fibre sources improved body weight gain and feed intake compared to the control diet (p < 0.01). Feed conversion ratio (FCR) improved with fibre supplementation (p < 0.01) and fine grinding of corn (FGC) (p < 0.01). Coarse grinding of corn (CGC) and inclusion of RH, SFH and OH reduced gizzard pH (p < 0.01). Fibre inclusion increased ileal fat and Ca digestibility (p < 0.01), gizzard weight (p < 0.01), digesta transit time (p < 0.01) and length of duodenum and small intestine (p < 0.01). The CAID of phosphorus increased in CGC fed birds and inclusion of RH, SFH and OH (p < 0.05). The weight of gizzard, proventriculus and pancreas (p < 0.01) was greater in CGC fed birds. Feeding SFH, RH and OH (p < 0.01), and CGC (p < 0.01) increased the villus height (VH) of the duodenum. The OH, RH and SFH supplementation increased the caecal population of Lactobacillus spp. and total anaerobic bacteria (p < 0.01) only in FGC fed birds. Overall, birds fed pelleted diets containing RH, OH and SFH (3%) exhibited improved performance, and increased nutrient digestibility, which may be caused by developed gizzards and intestine. Furthermore, coarse grinding of corn is beneficial to gizzard development.     

Influence of barley inclusion method and protease supplementation on growth performance,nutrient utilisation,and gastrointestinal tract development in broiler starters

The influence of the method of barley inclusion(fine,coarse and whole barley)in a wheat-based diet and protease supplementation(0 and 0.20 g/kg)on growth performance,nutrient utilisation and gastrointestinal tract development of broilers(d 1 to 21)was evaluated in a 3
2 factorial arrangement.Whole barley(WB)grains were ground in a hammer mill to pass through the screen sizes of 2.5 and 8.0 mm to achieve fine(FB)and coarse(CB)barley particle sizes,respectively.A total of 288,one-day-old male broilers were allotted to 36 cages(6 cages/treatment;8 birds/cage).There was no significant(P>0.05)interaction between barley inclusion method and protease for any growth performance or nutrient utilisation parameters.Birds fed diets containing CB and WB showed higher(P<0.05)weight gain,and digestibility of dry matter,nitrogen,calcium,gross energy,and ileal digestible energy compared to those fed FB diets.Compared to the birds fed FB diets,feed per gain was lower(P<0.05)in birds fed diets made of WB.Fat digestibility of the birds fed CB was higher(P<0.05)than those fed FB and WB birds.Compared to FB and CB diets,inclusion of WB resulted in heavier(P<0.05)gizzards but reduced(P<0.05)gizzard pH.Supplemental protease,however,had no effects(P>0.05)on growth performance and nutrient utilisation,most likely due to the well balanced digestible amino acids and high inherent digestibility of protein in the basal diet,and/or the presence of exogenous carbohydrase and phytase.In conclusion,the present results showed that the inclusion of coarsely ground and whole barley in a wheat-based diet can enhance nutrient and energy utilisation and is beneficial to the growth performance of young broilers.     

Effect of replacing corn with brown rice grain in a total mixed ration silage on milk production,ruminal fermentation and nitrogen balance in lactating dairy cows

Nine multiparous Holstein cows were used in a replicated 3 × 3 Latin square design to determine the effects of substituting corn grain with brown rice (BR) grain in total mixed ration (TMR) silage on milk yield, ruminal fermentation and nitrogen (N) balance. The TMR silages were made from the ensiling of TMR containing (dry matter basis) 50.1% forage in rice silage and corn silage combination, and 49.9% concentrate. The grain portion of the diets contained 31.2% steam‐flaked corn, 31.2% steam‐flaked BR or an equal mixture of corn and BR. Dietary treatments did not affect dry matter intake, milk yield and milk fat, protein and lactose yields. The ruminal pH and total volatile fatty acid concentrations were not affected by dietary treatment. The urinary N excretion decreased linearly (P < 0.01) in response to increased levels of BR, with no dietary effect on N intake, N secretion in milk and fecal N excretion. Our results indicate that steam‐flaked BR is a suitable replacement for steam‐flaked corn in dairy cow diets, and that it can be included in rations to a level of at least 31.2% of dry matter without adverse effects on milk production, when cows were fed rice silage and corn silage‐based diets.     

Effect of temperature,storage time,and sample type on sorbitol dehydrogenase activity in llama serum and plasma

Abstract: Serum and heparinized plasma samples were collected from 11 adult, clinically healthy llamas. Aliquots were assayed for sorbitol dehydrogenase (SDH) activity after storage at room temperature (20°C), 4°C, or −20°C for defined time intervals up to 1 week postcollection. Sorbitol dehydrogenase activity in all samples was within reference intervals for our laboratory. No difference was found between serum and plasma SDH activity when measured immediately (within 1 hour) after collection. Sorbitol dehydrogenase activity decreased to 79% of initial activity by 24 hours in serum stored at room temperature; plasma had 94% of initial SDH activity under the same conditions. Sorbitol dehydrogenase activity was stable in both plasma and serum stored for up to 1 week at 4°C or −20°C. With the exception of serum stored at 20°C for > 8 hours, in vitro stability of llama SDH was adequate for its use in diagnostic testing.     

不同储藏温度和时间对长白猪肌肉pH、失水率及脂质氧化的影响

研究测定了长白猪屠宰后12h肌肉pH的下降速度、极限值和肌间脂肪氧化速度,及不同储藏温度和时间对肌肉pH值、失水率及脂质氧化的影响。结果表明:屠宰后0～5h长白猪肌肉pH值下降速度较快,9～12hTBA值变化速度较快。4℃条件下,储存时间对长白猪肌肉pH影响不显著,对滴水损失影响极显著,TBA值影响显著;-20℃冷冻条件下,储存时间对长白猪肌肉pH、TBA影响显著,对解冻失水率影响不显著。温度对pH值和TBA值的影响不明显,对滴水损失和解冻失水率有极显著的影响。通过回归分析,长白猪肌肉滴水损失和解冻失水率随pH升高而降低;-20℃条件下TBA值随pH升高而升高。