Nutrient digestibility,but not mineral absorption,is age‐dependent in cats

Availability of nutrients is influenced by extremes of age, and a better characterization of this influence is necessary for appropriate development of foods and nutritional management throughout life stages of cats. This study investigated nutrient digestibility, mineral absorption, faeces and urine production in three groups of six young, mature and old cats fed two diets containing different energy densities. Apparent digestibility and mineral absorption were calculated by total collection method and values were tested with anova and regression analysis. A quadratic relationship was detected between age and digestibility of dry matter, organic matter, crude protein, acid‐hydrolysed fat and starch in the low‐energy diet. Starch digestibility showed the same response in the high‐energy diet. Young adult cats had intermediate digestibility, mature cats the highest and old cats the lowest. Mineral absorption (calcium, phosphorus, magnesium, sodium, potassium and chloride) and urinary pH were not different among groups. These findings confirm previous studies that found low digestibility of nutrients in some old cats, and support evidence that this trend is even more important in less digestible dry foods. On the contrary, data suggest that mineral formulations do not need to be varied in diets for adult cats of different ages.     

牛至油对断奶獭兔营养物质消化率和血液生化指标的影响

将60只35日龄左右断奶獭兔随机分为3组,对照组饲喂基础日粮,试验组在基础日粮中分别添加35mg/kg喹乙醇和100mg/kg10%牛至油,研究日粮中分别添加喹乙醇、牛至油后对断奶獭兔营养物质消化率和部分血液生化指标的影响。结果表明:牛至油能够显著提高断奶獭兔日粮中干物质表观消化率、蛋白质表观消化率和粗纤维表观消化率;牛至油可改善断奶獭兔血清白蛋白(ALB)、血清尿素氮(SUN)等部分血液生化指标。     

苜蓿青贮料替代苜蓿青干草对奶牛生产性能及乳品质的影响

试验旨在探讨苜蓿青贮料替代不同比例苜蓿青干草对奶牛生产性能、乳品质、营养物质表观消化率、血液生化指标及经济效益的影响。选取体重、产奶量、胎次相近的健康泌乳中期中高产中国荷斯坦奶牛15头,随机分为3组,每组5个重复,每个重复1头牛。对照组饲喂4.0 kg苜蓿青干草,试验A、B组分别用4.4,8.8 kg苜蓿青贮料代替2.0和4.0 kg等干物质的苜蓿青干草,正试期64 d。结果表明,1)各组间干物质采食量差异不显著(P>0.05),B组产奶量显著低于对照组(P<0.05),A组与对照组、B组间差异不显著(P>0.05); 2)用50%,100%的苜蓿青贮料替代等干物质的苜蓿青干草,其乳蛋白、乳脂率、乳糖均有所改善,但只有B组的乳脂率显著高于对照组(P<0.05),其余指标各组间差异均不显著(P>0.05);3)A、B组与对照组的中性洗涤纤维表观消化率、钙表观消化率无显著性差异(P>0.05),A、B组间粗蛋白和磷表观消化率差异不显著(P>0.05),但是粗蛋白表观消化率均显著低于对照组、磷表观消化率均显著高于对照组(P<0.05);4)苜蓿青贮料替代苜蓿青干草其血清总蛋白、白蛋白、血尿素氮、血糖、二氧化碳结合力等指标没有显著性改变(P>0.05);5)试验A、B组经济效益均有所增加,其中A组的净增收益最高,为0.61元/(头·d)。综上,用4.4 kg苜蓿青贮料代替2.0 kg苜蓿青干草对中高产奶牛是适宜的,能提高其生产性能,改善乳品质,增加收益。     

Effect of a novel animal milk oligosaccharide biosimilar on macronutrient digestibility and gastrointestinal tolerance,fecal metabolites,and fecal microbiota of healthy adult cats

GNU100 is a novel animal milk oligosaccharide (AMO) biosimilar. In a recent in vitro fermentation study, GNU100 was shown to be fermentable by feline gastrointestinal microbiota and lead to increased short-chain fatty acid production. Our objectives herein were to evaluate the palatability, safety, and gastrointestinal tolerance of GNU100 in healthy adult cats. Exploratory end-points were measured to assess utility. In study 1, 20 adult cats were used to test the palatability of diets containing 0% or 1% GNU100. In study 2, 32 (mean age = 1.9 yr; mean body weight = 4.6 kg) male (n = 12) and female (n = 20) adult cats were used in a completely randomized design. After a 2-wk baseline, cats were assigned to one of the following treatment groups and fed for 26 wk: control (CT, no GNU100), low dose (LD, 0.5% GNU100), medium dose (MD, 1.0% GNU100), and high dose (HD, 1.5% GNU100). On weeks 2, 4, and 26, fresh fecal samples were collected for the measurement of stool quality and immune and inflammatory markers and on weeks 2 and 4 for microbiota and metabolites. On week 4, total feces were collected to measure apparent total tract macronutrient digestibility. On weeks 2, 4, and 26, blood samples were collected for serum chemistry, hematology, and inflammatory marker measurement. The palatability test showed that 1% GNU100 was strongly preferred (P < 0.05), with GNU100 having a 17.6:1 consumption ratio compared with control. In the long-term study, all cats remained healthy, without any signs of gastrointestinal intolerance or illness. All diets were well accepted, resulting in similar (P > 0.05) food intake, fecal characteristics, immunoglobulin A, and calprotectin, and dry matter, organic matter, fat, and crude protein digestibilities. Fecal butyrate was greater (P = 0.02) in cats fed HD than cats fed LD or MD. Fecal indole was lower (P = 0.02) in cats fed HD than cats fed LD. Cats fed CT had a higher (P = 0.003) relative abundance of Actinobacteria than cats fed LD. The relative abundance of Peptococcus was impacted by diet and time. At 4 wk, Campylobacter was lower in fecal samples of cats fed HD. Overall, the data suggest that dietary GNU100 supplementation was highly palatable, well tolerated, did not cause detrimental effects on fecal quality or nutrient digestibility, increased fecal butyrate concentrations, and reduced fecal indole concentrations, supporting the safety of GNU100 for inclusion in feline diets and suggesting potential benefits on gastrointestinal health of cats.     

Urea utilization in growing lambs. 4. N balances with unprocessed rations

N balance experiments were carried out with lambs of the ages of 8, 12 and 15 weeks fed with wheat rations with and without 2% urea supplement (N 1 and N 2) as well as with 3% urea and 20% straw (N 3) or with a soya bean meal supplement (N 4). There were no significant differences in the digestibility of the crude nutrients and in per cent of N retention between the individual ages. The straw supplement decreased the digestibility of organic matter, crude protein, crude fibre and NfE. The supplements of soya bean meal or urea increased the crude protein content in comparison to the wheat ration without supplements by 6% in the dry matter and resulted in N intakes 55 ... 60% higher and in 23 ... 38% higher N retention, which was, however, lower in relation to N intake. There were no significant differences with regard to N retention between N 2, N 3 and N 4. Consequently urea supplement to the feed mixture with 14% native crude protein resulted in increased N retention, which was not lower than with a soya bean meal supplement.     

Comparison of Nutrient Digestibility Between Adult and Aged Horses

There is little published work comparing digestibility in healthy adult versus healthy aged horses. Researchers hypothesized that there would be no differences in macronutrient digestibility between eight adult (5–12 years) and nine aged (19–28 years) horses fed three diets in a Latin square design. Seventeen stock-type mares were randomly assigned for a 5-week period to one of three diets: hay only (HAY), hay plus a starch- and sugar-rich concentrate (CHO), or hay plus a fat- (oil) and fiber-rich concentrate (FF). Each diet period comprised 3 weeks of outdoor group drylot feeding, 2 weeks of indoor stalled individual feeding, followed by a 72-hour digestibility trial including total urine and fecal collection. Feed, fecal, and/or urine samples were analyzed to determine dry matter, crude protein, fat, energy, calcium, and phosphorus apparent retention as well as apparent digestibility. Neutral detergent fiber digestibility was also determined. Mean body weight was lower in aged than in adult horses (455 ± 12 kg vs. 500 ± 13 kg; P = .02), but body condition score (BCS) did not differ between groups (aged horses, 4.8 ± 0.2 BCS and adult horses, 5.1 ± 0.2 BCS; P = .20). No age differences in digestibility, apparent digestibility, or apparent retention were seen for any of the variables measured. Based on the results of this study, total tract macronutrient digestibility appears to be similar between healthy adult and aged horses.     

Digestibility for dogs and cats of meat and bone meal processed at two different temperature and pressure levels*

This study evaluated the effect of two rendering processes applied to meat and bone meal (MBM) production, associated or not with extrusion, by measuring diet apparent total tract digestibility of dogs and cats, and true digestibility of amino acids (AA) by cecectomized roosters. Four diets were evaluated, with the main protein source as follows: conventional and extruded MBM; high temperature and pressure (HPT; 135 °C, 3 bar, 20 min) and extruded MBM; conventional non‐extruded MBM; HPT non‐extruded MBM. Nutrient digestibility and food metabolizable energy content were evaluated with dogs and cats by the method of total collection of faeces. True AA digestibility was evaluated by a precision‐fed assay with cecectomized roosters. The evaluated MBM had high‐ash content. The HPT process of MBM increased the digestibility of crude protein of the diets by cats, and the true digestibility of several AA by cecectomized roosters. The extrusion process did not modify the apparent total tract nutrient digestibility of MBM by dogs and their amino acid digestibility by roosters, but increased the digestibility of the dietary protein by cats. Dogs fed HPT MBM presented a higher urea post‐prandial response, suggesting reductions in bioavailability and protein synthesis from absorbed AA.     

不同代谢能和粗蛋白质水平对合浦鹅日粮养分消化率及生长性能的影响

本文旨在研究日粮不同代谢能和粗蛋白质水平对合浦鹅日粮干物质、粗蛋白质、粗脂肪、粗纤维、钙和磷等养分的消化率及生长性能的影响.将120只28日龄的合浦鹅随机分成6个组,进行2个饲养和消化试验:试验1组饲喂粗蛋白质水平为15.10%,代谢能水平分别为10.03、11.00和11.85 MJ/kg的3种日粮;试验2组饲喂代谢能水平为11.50 MJ/kg,粗蛋白质水平分别为12.50%、14.85%和17.83%的3种日粮.用4 mol/L HCI ALA方法测定日粮的养分消化率.结果表明:粗蛋白质水平为15.10%和代谢能水平为10.03 MJ/kg的日粮,具有较高的养分消化率,但不同代谢能水平对试鹅的生长性能影响差异不显著(P>0.05);代谢能水平为11.50 MJ/kg和粗蛋白质水平为12.50%的日粮也具有较高的养分消化率,但不同粗蛋白质水平对试鹅的生长性能影响差异也不显著(P>0.05).因此,28日龄以后的合浦鹅的日粮粗蛋白质和代谢能水平分别为15.10%和10.03 MJ/kg,或分别为12.50%和11.50 MJ/kg时,均具有较高的养分消化率,但对合浦鹅的生长性能无显著影响.     

Clinical evaluation of dietary modification for treatment of spontaneous chronic kidney disease in cats

Objective-To determine whether a renal diet modified in protein, phosphorus, sodium, and lipid content was superior to an adult maintenance diet in minimizing uremic episodes and mortality rate in cats with stage 2 or 3 chronic kidney disease (CKD). Design-Double-masked, randomized, controlled clinical trial. Animals-45 client-owned cats with spontaneous stage 2 or 3 CKD. Procedures-Cats were randomly assigned to an adult maintenance diet (n = 23 cats) or a renal diet (22) and evaluated trimonthly for up to 24 months. Efficacy of the renal diet, compared with the maintenance diet, in minimizing uremia, renal-related deaths, and all causes of death was evaluated. Results-Serum urea nitrogen concentrations were significantly lower and blood bicarbonate concentrations were significantly higher in the renal diet group at baseline and during the 12- and 24-month intervals. Significant differences were not detected in body weight; Hct; urine protein-to-creatinine ratio; and serum creatinine, potassium, calcium, and parathyroid hormone concentrations. A significantly greater percentage of cats fed the maintenance diet had uremic episodes (26%), compared with cats fed the renal diet (0%). A significant reduction in renal-related deaths but not all causes of death was detected in cats fed the renal diet. Conclusions and Clinical Relevance-The renal diet evaluated in this study was superior to an adult maintenance diet in minimizing uremic episodes and renalrelated deaths in cats with spontaneous stage 2 or 3 CKD.     

Effects of short-chain fructooligosaccharides and galactooligosaccharides, individually and in combination, on nutrient digestibility, fecal fermentative metabolite concentrations, and large bowel microbial ecology of healthy adults cats

Short-chain fructooligosaccharides (scFOS) and galactooligosaccharides (GOS) are nondigestible oligosaccharides that result in a prebiotic effect in some animal species; however, the cat has not been well studied in this regard. This experiment evaluated scFOS and GOS supplementation on nutrient digestibility, fermentative end product production, and fecal microbial ecology of cats. Eight healthy adult cats were fed diets containing no prebiotic, 0.5% scFOS, 0.5% GOS, or 0.5% scFOS + 0.5% GOS (scFOS + GOS) in a replicated 4 × 4 Latin square design. Apparent total tract CP digestibility was decreased (P < 0.05) when cats were fed a diet containing scFOS + GOS compared with the other treatments. Dry matter, OM, acid hydrolyzed fat, and GE digestibilities were not different (P > 0.05) among treatments. Cats fed scFOS-, GOS-, and scFOS + GOS-supplemented diets had greater (P < 0.05) fecal Bifidobacterium spp. populations compared with cats fed the control diet. Fecal pH was less (P < 0.05) for cats fed the scFOS + GOS-supplemented diet compared with the control. Butyrate (P = 0.05) and valerate (P < 0.05) concentrations were greater when cats consumed the scFOS + GOS diet. Acetate tended (P = 0.10) to be greater when cats were fed the scFOS + GOS diet. Total short-chain fatty acid (P = 0.06) and total branched-chain fatty acid (P = 0.06) concentrations also tended to be greater when cats consumed the scFOS + GOS treatment. Fecal protein catabolites, including ammonia, 4-methylphenol, indole, and biogenic amines, blood lymphocytes, neutrophils, total white blood cell counts, or fecal DM concentration and output did not differ (P > 0.05) among treatments. Low level supplementation of scFOS, GOS, and their combination exert positive effects on select indices of gut health in cats.     

Feeding value of enset (Ensete ventricosum), Desmodium intortum hay and untreated or urea and calcium oxide treated wheat straw for sheep

Feed intake, in vivo nutrient digestibility and nitrogen utilization were evaluated in male sheep fed different fractions (leaf, pseudostem, corm, whole plant) of enset, untreated or 2% urea‐ and 3% calcium oxide‐ (CaO or lime) treated wheat straw and Desmodium intortum hay as sole diets. All feeds, except D. intortum hay and enset leaf had low crude protein (CP) content. Non‐fiber carbohydrate contents were higher in enset fractions, especially in pseudostem and corm relative to other feeds. Enset leaf and pseudostem had high calcium, phosphorus and manganese contents. Corm, whole enset and D. intortum hay were rich sources of zinc. Daily dry matter and CP intakes were higher (p < 0.05) in sheep fed D. intortum hay (830 and 133 g, respectively) than those fed pseudostem (92 and 7.8 g, respectively). Organic matter digestibilities were highest for corm (0.780) and whole enset (0.776) and lowest for D. intortum hay (0.534) and untreated wheat straw (0.522). The CP digestibility ranged from 0.636 in D. intortum hay to 0.408 in corm. Nitrogen (N) balance was highest (p < 0.05) in D. intortum hay (10.4 g/day) and lowest in corm (?1.3 g/day). Enset leaf could be a useful protein supplement whereas the pseudostem and corm could be good sources of energy.     

Blood pressure assessment in healthy cats and cats with hypertensive retinopathy

OBJECTIVE: To determine whether there was an association between hypertensive retinopathy and high systolic, diastolic, and mean arterial blood pressures in cats. ANIMALS: 181 cats. PROCEDURE: Systolic, diastolic, and mean arterial blood pressures were measured by use of a noninvasive oscillometric technique. The range of blood pressure measurements in healthy cats from various age groups was determined. Associations among systolic, diastolic, and mean arterial blood pressure; hypertensive retinopathy; hyperthyroidism; left ventricular cardiac hypertrophy; chronic renal failure; and serum biochemical abnormalities were determined. RESULTS: All blood pressure measurements increased with age in healthy cats. The frequency of hypertensive retinopathy also increased with age and with blood pressure, and hypertensive retinopathy was particularly found in cats with systolic blood pressures > 168 mm Hg. There was an increased risk for hypertensive retinopathy in cats that were female, > 10 years old, and neutered. The risk of chronic renal failure also increased as blood pressure, particularly systolic blood pressure, increased. CONCLUSIONS AND CLINICAL RELEVANCE: Hypertensive retinopathy was common in cats > or = 10 years of age and was associated with systolic blood pressures > 168 mm Hg when measured by the noninvasive oscillometric technique.     

Effect of Lysine Supplement on the Digestion and Metabolism of the Rumen in Small-tail Han Sheep

5 male Small-tail Han sheep with the body weight of 45 kg at 1.5 years old,fitted with permanent rumen fistula,to study of the effect of the supplement of the untreated commercial lysine on the rumen microbiocoenosis,rumen metabolism and whole body metabolism by 5×5 Latin square design (5 groups:control,control with low urea (equal nitrogen),low lysine,control with high urea (equal nitrogen),high lysine).The amounts of lysine-HCl supplement were 0,4.0 and 8.0 g/kg diet (as DM basis) in each group respectively,with two urea supplement control groups of equal amount of nitrogen.The results showed that by supplement of 4.0 and 8.0 g/kg of lysine-HCl diet (as DM basis) respectively,the voluntary intake of dry matter of sheep were increased by 5.5%(P>0.05) and 11.8%(P<0.05) respectively.The total amount of rumen bacteria were increased by 18.9%(P<0.01) and 23.9%(P<0.01) respectively,as the amount of rumen Coccus was increased by 21.2%(P<0.01) and 30.1%(P<0.01) respectively.The amount of rumen big Bacillus was decreased by 16.7%(P<0.05) and 33.3%(P<0.01) respectively.The total VFA of was increased by 9.6%(P<0.05) and 12.2%(P<0.01) respectively,as the butyric acid was increased by 12.8%(P>0.05) and 20.2%(P<0.01) respectively.The apparent digestibility of organic matter was increased by 6.4%(P>0.05) and 10.0%(P<0.05) respectively,the apparent digestibility of crude protein was increased by 7.0%(P>0.05) and 18.3%(P<0.01) respectively;And nitrogen retention was increased by 46.4%(P>0.05) and 110.7%(P<0.01) respectively.However,there was no effect of lysine supplement on the amounts of the rumen protozoa and fungi,and the concentration of rumen ammonia nitrogen.It was concluded that the supplement of untreated commercial lysine to adult sheep would increase the voluntary intake,digestibility,nitrogen retention the rumen microbiocoenosis and the total amount of rumen bacteria,especially the rumen Coccus of adult sheep.The effect of lysine supplement could not be replaced by urea supplement completely.     

添加赖氨酸对小尾寒羊瘤胃消化代谢的影响

试验选用5只1.5岁左右装有永久性瘤胃瘘管的小尾寒羊公羊(体重约45 kg),按照5×5拉丁方试验设计(对照组、低尿素对照(等氮)组、低赖氨酸组、高尿素对照(等氮)组、高赖氨酸组),研究添加未经任何处理的市售赖氨酸对成年小尾寒羊瘤胃微生物群落、瘤胃消化代谢和整体消化代谢的影响。赖氨酸盐酸盐添喂量分别为0、4.0和8.0 g/kg日粮(干物质计)。结果表明,绵羊添加4.0和8.0 g/kg赖氨酸盐酸盐日粮,自由采食量分别比对照组增加5.5%(P>0.05)和11.8%(P<0.05),瘤胃细菌总数分别增加18.9%(P<0.01)和23.9%(P<0.01),其中球菌分别增加21.2%(P<0.01)和30.1%(P<0.01),大杆菌数量减少16.7%(P<0.05)和33.3%(P<0.01),瘤胃液总挥发性脂肪酸分别比对照组增加9.6%(P<0.05)和12.2%(P<0.01),其中丁酸分别增加12.8%(P>0.05)和20.2%(P<0.01),有机物表观消化率分别增加6.4%(P>0.05)和10.0%(P<0.05),粗蛋白质表观消化率分别比对照组增加7.0%(P>0.05)和18.3%(P<0.01),氮保留率分别增加46.4%(P>0.05)和110.7%(P<0.01)。然而,添加赖氨酸对绵羊瘤胃原虫和真菌数量、瘤胃液氨态氮浓度均无显著影响(P>0.05)。由本试验得出结论,给成年小尾寒羊添加一定量的未经任何处理的市售赖氨酸,可提高小尾寒羊的日粮自由采食量和消化率,增加氮保留率;可调控瘤胃微生物群落的组成,增加瘤胃细菌总数,主要是瘤胃球菌数量;以上这些添加赖氨酸的作用是添加等氮量尿素所不能完全替代的。     

Efficacy of different phosphorus supplements for sows during gestation and lactation

This study was undertaken to compare dicalcium, Curacao, and soft ph sophates as supplemental feeding during gestation and lactation. In Exp eriment 1, 37 crossbred sows at 11 months of age were mated and each of 4 groups given an experimental diet. The basal diet was a 16% crude pro tein-fortified corn-soybean meal containing .34% of phosphorus and .72% of calcium. The test diets were fortified with either dicalcium, Curaca o, or soft phosphate to provide .52% of phosphorus. Limestone was given to maintain .72% of calcium. Animals were confined in a concrete feedin g area and fed 1.8 kg of diet per head per day until Day 94 of gestation . At that time the diet was increased to 2.3 kg/day. On Day 109 of gestation animals were moved to farrowing crates until 10 days postpartu m and then to wooden units until weening at 8 weeks. Sows were sacrific ed after 8 weeks lactation, or if they developed posterior paralysis. In this experiment, the different phosphate sources were without observed influence on the livability or performance of pigs up to 8 weeks of age (p less than .05). Gilts receiving no supplemental phosphorus had significantly lower bone ash and phosphorus than did those receiving either of the supplements. Posterior paralysis was observed in 5 of 9 sows fed the unsupplemented diet, in 3 of 9 fed the soft supplemented diet, and in 2 of 10 fed the Curacao phosphate supplement. None fed dicalcium phosphate developed paralysis. The paralysis usually occurred after 6 weeks of lactation and was often accompanied by a fractured femur. In Experiment 2, 70 sows were bred at 10 months of age and fed 1.8 kg of the experimental diets. During 36 days of lactation, phosphorus digestibility, retention, and balance were shown to be lower for those fed only the basal diet. Bone ash, bone phosphorus, and bone strength were lower in those fed the unsupplemented diet. Results of these studies indicate the need for supplemental phosphorus in sow feeding. When feeding dicalcium phosphate or Curacao phosphate the use of over .5% phosphorus in the sow's diet is unnecessary during gestation and lactation.     

复合微生态制剂对乌骨羊生产性能及养分表观消化率的影响

为研究复合微生态制剂对乌骨羊生产性能及养分表观消化率的影响,试验选择体重相近的乌骨羊90只,随机分成3个组,每个组3个重复,每个重复10只,1组饲喂基础日粮为空白对照组,2、3组分别在基础日粮中添加5.0%、10.0%的复合微生态制剂,试验期为60 d。试验期间测定生产性能和养分表观消化率。结果表明:(1)3组的试验末重和平均日增重分别较1组提高5.57%、31.16%(P<0.05),3组料重比较1组降低18.05%(P<0.05)。(2)3组的粗蛋白质、中性洗涤纤维、酸性洗涤纤维表观消化率较1组分别提高14.23%、19.19%、16.69%(P<0.05),2、3组的粗脂肪、粗灰分、钙、磷的表观消化率均高于1组(P>0.05)。综上,基础日粮中添加10.0%复合微生态制剂可以提高乌骨羊的生长性能和养分表观消化率。     

一种新型缓释尿素替代日粮中部分豆粕对肉牛生长性能、养分消化率及血液生化指标的影响

试验旨在研究一种新型缓释尿素替代日粮中部分豆粕对肉牛生长性能、养分消化率及血液生化指标的影响。选择18头健康、体重相近(315±5)kg、7月龄左右生长期西门塔尔杂交公牛,随机分为豆粕组、缓释尿素组和普通尿素组3组,每组6头牛。豆粕组饲喂含11.12%豆粕(粗蛋白质(CP)为15.51%、干物质(DM)为48.06%)的试验日粮(精粗比4∶6)。按照等能等氮原则,缓释尿素组和普通尿素组饲喂含缓释尿素和普通尿素分别占各自日粮的1.41%和1.15%,即2个试验组分别用缓释尿素和普通尿素替代豆粕组日粮中75%豆粕。预试期14 d,正试期60 d。结果表明:①各组间平均日增重和料重比均无显著差异(P>0.05),但缓释尿素组和普通尿素组的平均日采食量(ADMI)显著低于豆粕组(P<0.05)。②缓释尿素组和普通尿素组的干物质和有机物(OM)表观消化率显著高于豆粕组(P<0.05);缓释尿素组粗蛋白质的表观消化率显著低于普通尿素组(P<0.05),但与豆粕组相比无显著差异(P>0.05);普通尿素组粗脂肪(EE)表观消化率最低,豆粕组最高,各组间均存在显著差异(P<0.05);各处理组间的中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)的表观消化率均无显著差异(P>0.05)。③与豆粕组相比,缓释尿素替代日粮中部分豆粕未对肉牛各项血液生化指标产生影响(P>0.05);缓释尿素组的白蛋白(ALB)、谷丙转氨酶(ALT)和谷草转氨酶(AST)均显著高于普通尿素组(P<0.05)。由上述结果可知,缓释尿素和普通尿素可替代日粮中部分豆粕应用于肉牛生产中,且缓释尿素替代豆粕效果优于普通尿素。     

Effects of enzyme addition on the nutritive value of broiler diets containing hulled or dehulled Chinese double-low rapeseed meals

An in vitro and a feeding trial was conducted to investigate the effect of fibre-degrading enzymes A (xylanase + β-glucanase), B (xylanase) and C (xylanase + cellulase) on the nutritive value of broiler diets containing either hulled (22.5% and 23.5% for 4–21 days and 22–42 days of age, respectively) or dehulled (20% and 21.5%) Chinese double-low rapeseed meals (DLRM). Overall, in vitro digestibility of dry matter (DM) or neutral digestibility fibre (NDF) did not differ (p > 0.05) because of meal types; both crude protein (CP) and NDF digestibility was improved (p < 0.05) because of addition of enzymes B or C either to hulled or dehulled DLRM diets. Birds fed dehulled DLRM diets had a higher (p < 0.05) growth rate, feed efficiency and lower (p < 0.05) feed intake than those fed hulled DLRM diets during the overall phase. Enzyme C addition to dehulled DLRM diets resulted in improved (p < 0.05) growth rate and feed efficiency during 4–21 days of age. Enzymes A and B addition elicited a positive response in feed intake and weight gain (p < 0.05), respectively, but did not affect (p > 0.05) feed efficiency. It would appear that the nutritive value of broiler diets containing Chinese DLRM could be improved by appropriate xylanase-based enzymes. Responses of broilers to fibre-degrading enzymes could be highlighted by hull removal of fed DLRM.     

Comparison of corn gluten meal and meat meal as a protein source in dry foods formulated for cats

OBJECTIVE: To compare the nutritional value of corn gluten meal (CGM) and meat meal (MM) as a dietary source of protein in dry food formulated for adult cats. ANIMALS: 8 healthy adult cats (4 males and 4 females). PROCEDURE: Diets containing CGM or MM as the main protein source were each fed for a 3-week period in a crossover study. Digestibility and nutritional balance experiments were conducted during the last 7 days of each period. Furthermore, freshly voided urine was obtained to measure urinary pH, struvite crystals, and sediment concentrations. RESULTS: Daily food intake and dry-matter digestibility were significantly higher for the MM diet. Fecal moisture content also was higher for the MM diet. Apparent nitrogen (N) absorption and N retention were higher for the MM diet, even when values were expressed as a percentage to account for differences in N intake. Urinary pH, struvite activity product, number of struvite crystals in urine, and urinary sediment concentrations were not different between diets. Retention of calcium, phosphorus, and magnesium was lower for the CGM diet, and cats lost body calcium and magnesium when fed the CGM diet. CONCLUSIONS AND CLINICAL RELEVANCE: Meat meal was superior to CGM as a protein source in dry foods formulated for cats, because dry-matter digestibility and N utilization were higher for the MM diet. In addition, net loss of body calcium and magnesium for the CGM diet suggests that mineral requirements increase when CGM is used as a protein source.     

Oestradiol and genistein reduce food intake in male and female overweight cats after gonadectomy

AIM: To determine if exogenous oestradiol or the phyto-oestrogen genistein could reduce food intake in male and female cats fed ad libitum that had been allowed to accrue excessive bodyfat following neutering. METHODS: Sixteen adult (eight female, eight male) cats were neutered and allowed to increase their bodyweight (BW) through feeding ad libitum of a complete and balanced dry diet. Oestradiol was injected subcutaneously for 5-day periods in incremental doses (0.25-4 microg per cat), then food intake was recorded, and vaginal cytological changes were observed in females. Similarly, genistein was administered orally for 5-day periods in incremental doses (5-100 mg/kg). RESULTS: In males and females, both oestradiol (p<0.001) and genistein (p=0.037) significantly reduced food intake during treatment, and the minimum daily doses that produced a significant effect were 0.5 mug and 100 mg/kg, respectively. The minimum daily dose of oestradiol that produced a significant effect on food intake was not associated with changes in vaginal cytology over the 5-day treatment period. CONCLUSIONS AND CLINICAL RELEVANCE: Gonadal oestradiol appeared to be a key modulator of food intake in both male and female cats, and replacement of oestrogen to neutered cats via oestradiol or an oestrogen surrogate such as genistein has potential for reducing the prevalence of obesity in neutered cats.