母猪批次化生产猪场的各类猪群存栏数及占栏数的计算

合理的猪群结构、猪群组成及其周转是猪场均衡生产和提高效率的关键因素。目前,母猪批次化生产技术在猪场实施的过程中,各种参数的制定、各类猪群存栏数及占栏数的计算依据不清晰,容易出现错误。文中的研究以600头基础母猪、7 d为一个生产周期猪场为例,详细地阐述了生产参数的制定、不同猪群的存栏数和占栏数的计算依据和过程,以期为猪场设计人员的猪场设计与建设和养猪生产者生产工艺的制定提供参考。     

Determination of the nutritional value of lignocellulose materials

The determination of the nutritive value of various secondary wood products was conducted by the method of the in-vitro digestibility of dry matter (Mellenberger et al., 1970) and by detergent analyses of fibre (Goering and Van Soest, 1970). Rumen contents for trials in vitro were obtained from adult wethers having a permanent rumen fistula and fed good meadow hay ad lib. The animals also had free access to water and mineral lick for sheep. Out of the 11 lignocellulose materials tested, digestibility in vitro higher than 60% (equivalent to the digestibility of high-quality meadow hay) was only found in three samples. These are: a) beech sawdust II treated with 0.1M sulphuric acid at the hydromodulus of 1:8, temperature 100 to 130 degrees C for two hours, and pressure of 0.25 MPa and then with 0.47M nitric acid at the hydromodulus of 1:13, temperature 100 degrees C for two hours and pressure of 0.25 MPa; b) beech sawdust III treated as beech sawdust II and then neutralized with ammonia to pH 8; c) aspen sawdust treated hydrobarothermically at a temperature of 280 degrees C and pressure of 7 MPa in saturated vapour medium (Canon system). The high digestibility of these samples was due to a low lignin content so that the polysaccharides (cellulose and hemicelluloses) of these secondary wood sources could be sufficiently utilized by rumen microflora.     

利用体外产气法评定反刍动物饲料的营养价值

试验利用体外产气法评定反刍动物饲料的营养价值。对花生藤、木薯渣、柠檬酸渣和甜叶菊渣4种原料进行体外发酵试验,通过测定各种原料的24h累计产气量、干物质(DM)降解率和细菌氮含量来评定其对反刍动物的营养价值。试验结果表明:花生藤、木薯渣、柠檬酸渣和甜叶菊渣的24h累计产气量分别为93.50、106.25、117.25和54.33ml;DM降解率分别为34.76%、48.34%、24.66%和33.63%;细菌氮含量分别为1.48、1.10、1.54和1.59mol/(g·ml)。总体来看,这几种饲料可以作为反刍动物的新型饲料资源加以推广利用,而且用体外产气法评定反刍动物饲料的营养价值是可行的。     

利用体外产气法评定反刍动物饲料的营养价值

本试验利用体外产气法评定反刍动物饲料的营养价值.对花生藤、木薯渣、柠檬酸渣和甜叶菊渣4种原料进行体外发酵试验.通过测定各种原料的24 h累计产气量、干物质(DM)降解率和细菌氮含量来评定其对反刍动物的营养价值.试验结果表明,2 g花生藤、木薯渣、柠檬酸渣和甜叶菊渣样品的24 h累计产气量分别为93.50、106.25、117.25 mL和54.33 mL;DM降解率分别为34.76%、48.34%、24.66%和33.63%;细菌氯含量分别为1.48、1.10、1.54mol/(g·mL)和1.59 mol/(g·mL).总体来看,这几种饲料可以作为反刍动物的新型饲料资源加以推广利用,而且用体外产气法评定反刍动物饲料的营养价值是可行的.     

DDGS对蛋鸡营养价值评定

为研究酒精糟及残液干燥物(DDGS)营养价值(与豆粕比较),测定了DDGS常规养分,结果表明DDGS的粗蛋白、粗脂肪、粗纤维、CaP2,P含量分别为40.00%、8.60%、7.45%、0.10%和0.60%。其中粗纤维和粗脂肪含量高于豆粕,其余养分含量与豆粕相当。并选用12只成年蛋用公鸡,采用随机区组设计测定了DDGS和豆粕中粗蛋白表观代谢率和表观代谢能,结果表明二者差异不显著(P>0.05),表明DDGS对蛋鸡有较高的营养价值。     

非常规蛋白质饲料原料的营养价值及在养猪业上的应用

<正>近年来,随着我国畜禽业的发展,我国对豆粕和大豆的需要量越来越大。据海关统计,2007年度,我国大豆进口量为3082.1万t,2008年度,     

Assessment of the value of the vertebral heart scale in the radiographic diagnosis of cardiac disease in dogs

In order to assess the influence of the vertebral heart scale (VHS) on the accuracy of the radiographic diagnosis of cardiac disease, thoracic radiographs of 50 dogs with proven cardiac disease, 26 with other thoracic diseases, and 50 with no clinical signs of cardiovascular or respiratory disease were mixed and examined by three independent, blinded observers chosen to represent a range of radiographic abilities. They first examined all the radiographs without making measurements of VHS and made a diagnosis. They then re-examined the radiographs, and measured VHS on both lateral and dorsoventral or ventrodorsal radiographs before again recording a diagnosis without reference to their original diagnoses. For all the observers, the dogs with cardiac disease had a higher mean VHS than the normal dogs. A VHS over 10.7 on the lateral radiograph was a moderately accurate sign of cardiac disease. The observers' accuracy of diagnosis did not change significantly as a result of using VHS as an adjunct to a subjective assessment of the radiographs.     

Assessment of the value of quantitative thyroid scintigraphy for determination of thyroid function in dogs

Objective : To assess the value of thyroid scintigraphy to determine thyroid status in dogs with hypothyroidism and various non‐thyroidal illnesses. Methods : Thyroid hormone concentrations were measured and quantitative thyroid scintigraphy performed in 21 dogs with clinical and/or clinicopathological features consistent with hypothyroidism. Results : In 14 dogs with technetium thyroidal uptake values consistent with euthyroidism, further investigations supported non‐thyroidal illness. In five dogs with technetium thyroidal uptake values within the hypothyroid range, primary hypothyroidism was confirmed as the only disease in four. The remaining dog had pituitary‐dependent hyperadrenocorticism. Two dogs had technetium thyroidal uptake values in the non‐diagnostic range. One dog had iodothyronine concentrations indicative of euthyroidism. In the other, a dog receiving glucocorticoid therapy, all iodothyronine concentrations were decreased. Markedly asymmetric technetium thyroidal uptake was present in two dogs. All iodothyronine concentrations were within reference interval but canine thyroid stimulating hormone concentration was elevated in one. Non‐thyroidal illness was identified in both cases. Clinical Significance : In dogs, technetium thyroidal uptake is a useful test to determine thyroid function. However, values may be non‐diagnostic, asymmetric uptake can occur and excess glucocorticoids may variably suppress technetium thyroidal uptake and/or thyroid hormone concentrations. Further studies are necessary to evaluate quantitative thyroid scintigraphy as a gold standard method for determining canine thyroid function.     

体外法估测日粮和饲料原料外源代谢葡萄糖值

试验旨在建立体外测定日粮和常用饲料原料中外源代谢葡萄糖(MG)含量的方法。试验采用单因子设计,以小肠消化时间为处理因素,分为1、2、4、6 h和8 h共5个处理。通过胃蛋白酶-胰蛋白酶两段法以四种不同日粮为底物进行体外模拟消化。将体外法测得的日粮淀粉降解率与体内法测得的日粮淀粉消化率进行相关性对照,确定两者相关系数最高的时间点,且将此设定为体外模拟消化的最佳时间。用此模拟消化时长,测定6种猪料原料外源MG水平。结果显示,体外法测定淀粉消化率,最佳的消化时长为6 h,此时与体内法测定的淀粉消化率建立的回归方程为:y=0.137 4x+84.834(R2=0.871 1)。最终得到体外法估测日粮外源MG的公式:外源MG=小肠淀粉量×(0.14×体外法测的小肠淀粉消化率+84.83)/0.9,并根据此方法测定出了几种常用饲料原料外源MG。     

减少肉种鸡场窝外蛋的方法

窝外蛋是许多肉种鸡场都可见到的问题,仅靠集蛋是无法得到解决的,其解决需要在饲养管理方式上作出改变。在理想生产条件下,窝外蛋有可能降低至1%以内。     

Individual variation in prelaying behaviour and the incidence of floor eggs

1. Floor eggs are a problem in non‐cage systems for laying hens, as they require secondary egg collecting. Failure to lay in a well‐defined nest site may also be a welfare problem for the hens, but only if their nesting motivation has been thwarted.

2. We investigated the relationships between a hen's prelaying behaviour and its tendency to lay on the floor by recording the behaviour of 20 hens housed individually in wire cages with single littered nest boxes.

3. Most floor eggs (80%) were laid by the same 6 hens. These 6 “floor‐layers” performed more nest seeking behaviour, less nest‐building behaviour and less sitting prior to oviposition than the 14 hens that consistently laid in nest boxes.

4. The incidence of floor eggs declined with age. Both nest and floor laying hens performed less nest seeking behaviour with age. Floor layers, however, increased their performance of nesting behaviour, whilst nest layers performed less nesting behaviour with age.

5. Floor laying hens behaved as if they found the nest box less attractive than nest‐laying hens; perhaps because they had lower nesting motivation, or perhaps because their nesting motivation was as high, but they less readily perceived the nest box as an appropriate nest site.     

The enhancement of the nutritive value of mango seed kernels for poultry by thermal treatment and radiation processing.

Raw seed kernels of local mango varieties (Magnifera indica L.) were analyzed for composition, levels of trypsin inhibitors, tannins, cyanogenetic glucosides, in vitro protein digestibility and apparent metabolizable energy (AMEN) as being effected by boiling, autoclaving as well as irradiation at 5, 10, 15, and 20 kGy. The air-dry mango seed kernels (MSK) contained CP 70 g kg-1, EE 128 g kg-1, and tannins 67 g kg-1. Compared with raw kernels the contents of trypsin inhibitory activity (30 TIU g-1) and cyanogenetic glucosides, measured as hydrocyanic acid (71 mg kg-1), were lowered by boiling, autoclaving and radiation treatments. Tannin content (67.2 g kg-1 in raw kernels) was decreased only by boiling or autoclaving, but irradiation did not introduce any effect. The low in vitro protein digestibility and AMEN values of raw MSK were enhanced by processing. The improvements were paralleled to reductions in trypsin inhibitory activity, cyanogenetic glucosides and tannin contents. Greater improvements were noticed with boiling and autoclaving than with irradiation alone. Autoclaving for 30 min plus irradiation treatment up to 20 kGy increased the in vitro protein digestibility and AMEN by 139% and 72%, respectively. These results indicate that tannins, trypsin inhibitors and cyanogenetic glucosides are responsible for the poor nutritive value of MSK. The effects of feeding 200 g kg-1 raw or processed MSK on the performance of broiler chicks were examined. The inclusion of raw kernel affected body weight gain and feed consumption, while weight gain of birds fed the autoclaved (30 min) plus irradiated (20 kGy) kernels was significantly more improved than by the other treatments. However, feed conversion ratio was not significantly different between groups fed the processed MSK. The results showed that the combination of autoclaving for 30 min plus irradiation up to 20 kGy upgraded the nutritive value more than the other tested treatments and that this method is most effective in processing MSK to be used as animal feed.     

Assessment of the feeding value of South Dakota-grown field peas (Pisum sativum l.) for growing pigs

Four experiments were conducted to investigate the feeding value of South Dakota-grown field peas (Pisum sativum L.) for growing pigs. In Exp. 1, 96 pigs (initial BW = 22 +/- 3.35 kg) were allotted to four treatment groups (four pigs per pen, six replicate pens per treatment) and fed growing (0.95% Lys) and finishing (0.68% Lys) diets containing 0, 12, 24, or 36% field peas (as-fed basis). There were no differences among the treatment groups in ADG, ADFI, or G:F. Likewise, there were no differences in backfat thickness or lean meat percent among treatment groups, but pigs fed diets containing 12, 24, or 36% field peas had greater (P < 0.05) loin depths than pigs fed the control diet. In Exp. 2, 120 pigs (initial BW = 7.8 +/- 1.04 kg) were allotted to four treatment groups 2 wk after weaning. Pigs were then fed diets containing 0, 6, 12, or 18% field peas (as-fed basis) during the following 4 wk. There were five pigs per pen and six replicate pens per treatment. Results of the experiment showed no differences in ADG, ADFI, or G:F among treatment groups. In Exp. 3, apparent (AID) and standardized (SID) ileal digestibility coefficients of CP and AA in field peas and soybean meal were measured using six individually penned growing pigs (initial BW = 36.5 +/- 2.1 kg) arranged in a repeated 3 x 3 Latin square design. The AID for Met, Trp, Cys, and Ser, and the SID for Met, Trp, and Cys were lower (P < 0.05) in field peas than in soybean meal; but for CP and all other AA, no differences in AID or SID were observed between the two feed ingredients. Experiment 4 was an energy balance experiment conducted to measure the DE and ME concentrations in field peas and corn. Six growing pigs (initial BW = 85.5 +/- 6.5 kg) were placed in metabolism cages and fed diets based on field peas or corn and arranged in a two-period switch-back design. The DE values for field peas and corn (3,864 and 3,879 kcal/kg DM, respectively) were similar, but the ME of corn was higher (P < 0.05) than the ME of field peas (3,825 vs. 3,741 kcal ME/kg DM). The results from the current experiments demonstrate that the nutrients in South Dakota-grown field peas are highly digestible by growing pigs. Therefore, such field peas may be included in diets for nursery pigs and growing-finishing pigs in amounts of at least 18 and 36%, respectively, without negatively affecting pig performance.     

地面平养蛋鸡就巢行为的遗传改善

在许多发达国家,存在着一种放弃利用传统鸡笼饲养蛋鸡的趋势,并且提供了替代型饲养系统及设施。如：散养系统（图1）、室内地面放养（图2）、大鸟笼式饲养系统（多层式地面平养禽舍）（图3）、改良式笼养系统（增设巢、沙浴和栖木等装置）（图4）。     

The use of perches by broilers in floor pens

1. Small flocks of broilers, numbering between 160 and 240, were placed in two deep‐litter pens each 10.13 m² in area, one of which contained four perches each 3.05 m long and about 0.3 m above the floor. The presence of birds on the perches was noted. Body weights at 56 d were recorded and food intakes from 0 to 56 d measured.

2. In experiments 1 and 2, when 160 birds without perches were compared with 240 with perches, the latter gained slightly less weight but had an improved food conversion efficiency. At 8 weeks about 27% of the birds were observed on the perches at any one time.

3. In experiments 3 and 4 both pens contained about 200 birds. Those with perches gained slightly more weight and food conversion efficiencies were similar. At 8 weeks about 12% of the birds were observed on the perches.

4. Perch usage appeared to be governed both by the age and size of the birds and by their density. In all four experiments the numbers perching at 8 weeks seemed to be such that the density of birds on the floor was about 17 birds/m² (28 to 34 kg/m²).