A study of periodontal disease in sheep over a twelve month period

Sheep affected by broken mouth periodontal disease (P.D.) were examined over a twelve month period for different clinical parameters. It is suggested that P.D. in sheep is an episodic phenomenon similar to human P.D., and that only a few animals with signs of P.D. may undergo clinically significant destruction over a yearly period. No single parameter could reliably predict future deterioration in other parameters.     

Daily and alternate day supplementation of urea or biuret to ruminants consuming low-quality forage: I. Effects on cow performance and the efficiency of nitrogen use in wethers

Two experiments were conducted to determine the influence of supplemental nonprotein N (NPN) provided daily (D) or every other day (2D) on ruminant performance and N efficiency. Treatments included an unsupplemented control (CON) and a urea (28.7% CP) or biuret (28.6% CP) supplement provided D or 2D at 0700. In Exp. 1, five wethers (39 +/- 1 kg BW) were used in an incomplete 5 x 4 Latin square with four 24-d periods to determine the influence of supplemental NPN source and supplementation frequency (SF) on the efficiency of N use in lambs consuming low-quality grass straw (4% CP). The amount of CP supplied by each supplement was approximately 0.10% of BW/d (averaged over a 2-d period). In Exp. 2, 80 Angus x Hereford cows (540 +/- 8 kg BW) in the last third of gestation were used to determine the effect of NPN source and SF on cow performance. The NPN treatments were formulated to provide 90% of the estimated degradable intake protein requirement. The supplemented treatments received the same amount of supplemental N over a 2-d period; therefore, the 2D treatments received double the quantity of supplemental N on their respective supplementation day than the D treatments. In Exp. 1, total DM, OM, and N intake; DM, OM, and N digestibility; N balance; and digested N retained were greater (P < 0.03) for supplemented than for CON wethers, with no difference (P > 0.05) between NPN sources or SF. Plasma urea-N (PUN) was increased with N supplementation compared with CON (P < 0.01), and urea treatments had greater PUN than biuret (P < 0.01). In addition, PUN was greater (P = 0.02) for D than for 2D treatments. In Exp. 2, pre- and postcalving (within 14 d and 24 h after calving, respectively) cow weight and body condition score change were more positive (P < 0.05) for supplemented groups than for CON. These results suggest that supplements containing urea or biuret as the primary source of supplemental N can be effectively used by lambs and cows consuming low-quality forage, even when provided every other day.     

Effects of implant regimens (trenbolone acetate-estradiol administered alone or in combination with zeranol) and vitamin D3 on fresh beef color and quality

In the first oftwo experiments, 123 calf-fed steers were used over a 2-yr period to evaluate the effects of trenbolone acetate (TBA)-based implants administered alone or in combination with zeranol implants on fresh beef muscle quality, color, and physiological maturity of the carcass. Implant treatments decreased (P < 0.05) a* values (d 0 and d 3 of retail display) and b* values (d 0, d 1, and d 3 of retail display) after 14 d of aging. Carcasses from cattle initially implanted with Revalor-S and reimplanted with Revalor-S on d 60 of the finishing period showed increased lean and bone maturity scores and ash content of the 9th to 11th thoracic buttons and Warner-Bratzler shear force values (WBS) compared to those initially implanted with Ralgro and subsequently reimplanted with Revalor-S or control cattle. In addition, implants decreased (P < 0.05) marbling, percentage of the carcasses grading Choice, and kidney, pelvic, and heart fat (KPH). Implant treatments increased (P < 0.05) ADG, hot carcass weights, and longissimus muscle (LM) area. In the second experiment over a 2-yr period, 166 steers fed as yearlings were allotted to one of two implant treatments and one of two vitamin D3 preharvest supplementation treatments. Implanted steers had heavier (P < 0.05) final body weights and higher (P < 0.05) ADG, less (P < 0.05) KPH fat, and larger (P < 0.05) LM. Also, implanted steers had more (P < 0.05) advanced bone maturity scores, higher (P < 0.05) ash content of the 9th to 11th thoracic buttons, and higher (P < 0.05) WBS values on 5-d postmortem loin steaks. Vitamin D3 feeding decreased (P < 0.05) final live weight, ADG (P < 0.05), and LM (P < 0.05), but did not significantly improve WBS values. In Experiment 2, neither implant treatment nor vitamin D3 supplementation had significant effects on L*, a*, or b* values of muscles in steaks before or during simulated retail display.     

THE EFFECTIVENESS OF LEVAMISOLE HYDROCHLORIDE IN THE TREATMENT OF ADULT DIROFILARIA IMMITIS

Dogs infected with D. immitis were treated with oral levamisole hydrochloride at various dose rates over different durations. Clinical toxicity, haematological and biochemical parameters, body weight and food intake were recorded and filarial mortality estimated at autopsy. All filariae were dead in dogs treated at 10 mg/kg body weight twice daily (12 hourly) for 14 days, with minimal clinical toxicity being seen during the treatment period.     

Serial assessment of the coagulation status of dogs with immune-mediated haemolytic anaemia using thromboelastography

This study investigated the coagulation status of dogs with immune-mediated haemolytic anaemia (IMHA) over time. Thirty animals with primary IMHA were blood sampled on three occasions over a 5 day period and assays performed included prothrombin time, activated partial thromboplastin time, D-dimer and fibrinogen concentration, antithrombin activity and recalcified unactivated thromboelastography (TEG). Based on TEG, dogs with IMHA were significantly hypercoagulable vs. controls (P<0.001) and over the 5 day period, 3/4 of the TEG parameters reflected increased clotting kinetics (P ≤ 0.02). The 30 day survival of these patients was 80% and, at hospital admission, the TEG maximum amplitude (MA) was significantly higher in survivors than non-survivors (P=0.015). Each unit increase in MA was associated with an increased odds of 30 day survival of 1.13 (95%; CI 1.02-1.25). Based on TEG, most dogs with IMHA were hypercoagulable on admission and their clotting kinetics increased with time. Relative hypocoagulability identified by TEG at initial assessment was found to be a negative prognostic indicator.     

水分胁迫下墨西哥羽毛草耐旱生理

本研究以一年生墨西哥羽毛草(Nassella tenuissima)为试验材料,采用盆栽控水法对墨西哥羽毛草进行水分胁迫,测定其各项指标,以期为墨西哥羽毛草的养护管理与在园林中的合理应用提供理论基础。结果表明,土壤水分为田间最大持水量的20%、40%、60%处理(D20、D40、D60)的植株株高生长速度和叶片相对含水量随干旱胁迫时间的延长而大幅度地降低,复水后D₂₀、D₄₀、D₆₀各处理的叶片含水量与对照(土壤水分为田间最大持水量的80%)相差7.11%、2.68%、0.80%,只有D₂₀处理与对照差异显著(P<0.05)未恢复到对照水平;相对电导率和丙二醛(MDA)含量随各处理水分胁迫时间的延长而呈逐步增加的趋势,复水后,D₂₀、D₄₀、D₆₀各处理相对电导率分别比对照高12.1%、5.92%、2.42%,D₂₀、D₄₀、D₆₀处理MDA含量分别为对照的152.18%、151.92%、133.97%,与对照差异显著(P<0.05);在水分胁迫下的超氧化物歧化酶(SOD)和过氧化酶(POD)活性均呈先上升后下降的变化趋势,复水后,D₂₀、D₄₀、D₆₀各处理SOD活性恢复到对照的82.65%、90.68%、97.13%,只有D₂₀处理与对照差异显著(P<0.05),其余处理均恢复到对照水平,D₂₀、D₄₀、D₆₀处理POD活性与对照相差7.54%、5.55%、11.73%,D₂₀、D₄₀处理与对照差异显著(P<0.05)。通过本研究可以得出,墨西哥羽毛草具有较强的抗旱性,能够适应40%田间持水量的土壤水分条件,是干旱地区优良的园林地被植物。     

Growth and somatic production estimates of Dosinia hepatica (Lamark) (Mollusca: Bivalvia) in the Swartkops estuary,South Africa

Regular and quantitative sampling for Dosinia hepatica was performed in the Swartkops estuary over a period of a year. The size of the D. hepatica recorded at LWMST was significantly (P<0,01) larger than that sampled at 0,4 m above LWMST This appeared to be a result of a spatial separation of large and small individuals. Size frequency analyses of the populations sampled and growth ring lengths were used to construct a growth curve for D. hepatica. The calculated growth rate was slow, with D. hepatica reaching a shell length of approximately 16,3 mm and a dry tissue mass of ca. 44 mg after three years. The potential life span of the bivalve was estimated to be 8-9 years. The annual somatic production (per m2) of the population sampled was calculated to be 0,58 g shell free dry mass or 8,63 kJ, while the production biomass (P/B) ratio was 0,3.     

初乳清粉的货架期预测和贮藏稳定性

为了掌握初乳清粉的贮藏特性,采用货架期预测方程来估计初乳清粉在室温(25℃)、50％相对湿度(RH)条件下PET包装的货架期,并对90d贮藏期过程中其理化指标以及生化指标的变化进行研究.研究结果表明:在PET包装90d贮藏时间内,初乳清粉的水分含量、硫代巴比妥酸(TBA)值和羟甲基糠醛(HMF)含量均随贮藏时间的延长而显著增加(P＜0.05),色差随贮藏时间的延长有所波动,但总体呈现上升趋势,而免疫球蛋白(IgG)的含量在60d内逐渐降低,60d后其下降不显著;在25℃、50％ RH条件下PET包装的初乳清粉的货架期为99.40d.     

Daily and alternate-day supplementation of urea or biuret to ruminants consuming low-quality forage: III. Effects on ruminal fermentation characteristics in steers

Five ruminally and duodenally cannulated steers (491 +/- 21 kg BW) were used in an incomplete 5 x 4 Latin square with four 24-d periods to determine the influence of supplemental nonprotein N (NPN) source and supplementation frequency (SF) on the dynamics of ruminal fermentation in steers consuming low-quality grass straw (4% CP). Treatments (TRT) included an unsupplemented control (CON) and a urea or biuret supplement that were placed directly into the rumen at 0700 daily (D) or every other day (2D). The NPN treatments were formulated to provide 90% of the estimated degradable intake protein requirement; therefore, the urea and biuret treatments received the same amount of supplemental N over a 2-d period. Daily TRT were supplemented with CP at 0.04% of BW/d, whereas the 2D TRT were supplemented at 0.08% of BW every other day. Forage was provided at 120% of the previous 5-d average intake in two equal portions at 0715 and 1900. Ruminal fluid was collected 0, 3, 6, 9, 12, and 24 h after supplementation on a day of and a day before supplementation for all TRT. Ruminal NH3-N increased (P < 0.04) with CP supplementation on the day all supplements were provided and on the day on which only daily supplements were provided compared with the CON. However, an NPN source x SF interaction (P = 0.03) on the day all supplements were provided indicated that NH3-N increased at a greater rate for urea as SF decreased compared with biuret. Ruminal NH3-N on the day only daily supplements were provided was greater (P = 0.02) for D compared with 2D. On the day all supplements were provided, D increased (P = 0.05) ruminal indigestible acid detergent fiber passage rate and ruminal fluid volume compared with 2D. These results suggest that urea or biuret can be used effectively as a supplemental N source by steers consuming low-quality forage without adversely affecting ruminal fermentation, even when provided every other day.     

Daily and alternate-day supplementation of urea or biuret to ruminants consuming low-quality forage: II. Effects on site of digestion and microbial efficiency in steers

Five steers (491 +/- 21 kg BW) were used in an incomplete 5 x 4 Latin square with four 24-d periods to determine the influence of supplemental non-protein N (NPN) source and supplementation frequency (SF) on nutrient intake and site of digestion in steers consuming low-quality grass straw (4% CP). Treatments (TRT) included an unsupplemented control and a urea- or biuret-containing supplement placed directly into the rumen daily (D) or every other day (2D) at 0700. The NPN treatments were formulated to provide 90% of the estimated degradable intake protein requirement. Daily TRT were supplemented CP at 0.04% of BW/d, whereas the 2D TRT were supplemented at 0.08% of BW every other day. Therefore, all supplemented TRT received the same quantity of supplemental CP over a 2-d period. Forage OM intake was not affected (P > 0.05) by NPN supplementation, NPN source, or SF; however, total OM and N intake were increased (P < 0.01) with CP supplementation. Duodenal flow of N was greater (P = 0.04) with CP supplementation compared with the control. In addition, duodenal bacterial N flow was increased with CP supplementation (P = 0.04) and for biuret compared with urea (P < 0.01). Bacterial efficiency (g bacterial N/kg OM truly digested in the rumen) was greater (P = 0.05) for biuret than for urea. Apparent total-tract N digestibility was increased with NPN supplementation (P < 0.01) but not affected by NPN source or SF. These results suggest that urea or biuret can be used effectively as a supplemental N source by steers consuming low-quality forage.     

THE PLACE OF VETERINARY ANAESTHESIA IN "THE FUTURE ROLE AND EDUCATIONAL NEEDS OF THE VETERINARY PROFESSION" AND RECOMMENDATIONS REGARDING FRAMEWORK OF EMPLOYMENT OR POSTGRADUATE TRAINING IN VETERINARY ANAESTHESIA

I would say that the ultimate position holders of the D.V.A. find themselves in, is very largely dependent on the course of events over the next few years and in no small measure to their own endeavours. I feel that the holders of the D.V.A. should view this training period as one in which they have enlarged their own over all appreciation of the subject they have studied and have therefore, gained for themselves a material advantage over other members of the profession who have not in fact followed this line of study and that although there is a certain amount of despondency in the ranks of the veterinary anaesthetists at the moment, this should not be allowed to become an obstacle in the progressive development of this group.     

Vitamin D3 requirement of young chicks receiving diets varying in calcium and available phosphorus

1. Three battery experiments were conducted with broiler chicks during the 2nd and 3rd week of life. Graded amounts of cholecalciferol (D3) were added to maize-soyabean meal diets that were designed to be (a) severely deficient in available phosphorus (P), (b) marginally deficient in calcium (Ca) or (c) adequate in both available P and Ca. 2. With diets containing 1.0 g available P and 6.3 g Ca/kg (assay 1), graded doses of D3 between 0 and 37.5 mu/kg produced linear (P 0.05) positive responses in both weight gain and tibia ash. With a D3 concentration of 1250 mug/kg, 250 times the requirement recommended by the NRC, bone ash was increased (P 0.05) over that of birds fed 37.5 mug/kg, and neither weight gain nor food intake were reduced. 3. With a P- adequate diet (4.5 g available P/kg) containing 8.5 g Ca/kg (assay 2), weight gain and bone ash increased linearly (P 0.05) upon supplementing the basal diet with 0, 2.5 and 5.0 mug D3/kg. Higher doses of D3 did not elicit further responses, and chicks fed on a diet containing 1250 mug D3/kg gained as fast and had bone ash values that did not differ from those of chicks receiving 5, 10, 20 or 40 mug D3/kg. 4. When the maize-soyabean meal basal diet was fortified with Ca and P to achieve adequate amounts of Ca (10.1 g/kg) and P (4.5 g available P/kg) in assay 3, dietary additions produced results similar to those obtained in assay 2 where P was adequate and Ca was slightly deficient. Again, chicks receiving a surfeit of D3 (1250 mug/kg) exhibited weight gains and bone ash values that were as great as those of chicks receiving 5, 10, 15 or 30 mug D3/kg. 5. It is apparent that young chicks have a high tolerance for excess D3, and chicks fed on diets that are severely deficient in available P continue to respond to D3 in excess of 37.5 mug/kg.     

The effect of biotechnological treatment of milk-replacer feeding mixtures on hematologic and biochemical parameters and its utilization in calves

A trial was performed with cellulase administration (3 cx per g of ingested feed dry matter) to early weaned calves fed minimum amounts of milk replacer (21 kg per milk nutrition period) and sweet (C, D) and sour (A, B) diets. The groups B and D were supplemented with an enzyme till the age of 90 days. The calves were given free choice of COT concentrate mixture, hay and water. Liveweight gains, feed and nutrient intake and health condition of calves were the characteristics investigated in this trial. Hematocrit value, hemoglobin, glucose and urea contents were determined in blood, in blood plasma buffer capacity was investigated. Although the differences in calf performance are not statistically significant, the best growth of calves in the vegetable nutrition period was observed in calves in group D. Nutrient conversion was also higher in calves of group D in the vegetable nutrition period. In conversion of nutrient consumption per 1 kg liveweight gain the difference in the intake of digestible crude protein and starch units between the group of calves fed sweet milk without enzyme addition in the milk nutrient period (A--digestible crude protein 0.40 +/- 0.005; starch units 1.74 +/- 0.008) and group D (sour diet + 3 cx cellulase--digestible crude protein 0.34 +/- 0.007; starch units 1.52 +/- 0.044) was statistically significant (P less than 0.025 and P less than 0.05) in favour of group D. An analysis of the results of hematological and biochemical investigations during the trial demonstrates that the sour diet is better in view of changes in glucose concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)     

不同水平蛋氨酸对埋植褪黑激素母貂营养物质消化率和血清生化指标的影响

采用单因素随机试验设计,选择离乳恢复期及冬毛生长期经产美国短毛黑母貂40只,随机分成A、B、C、D 4组,分别饲喂在基础日粮中添加0%、0.2%、0.4%和0.6%蛋氨酸的4种试验饲粮,以探讨不同水平蛋氨酸对埋植褪黑激素水貂生产性能的影响。结果表明:添加不同水平蛋氨酸后4组水貂干物质、粗蛋白、粗脂肪、能量的消化率表现为差异不显著(P0.05)。试验C组干物质采食量显著高于A、D组(P0.05);试验组与对照组增重、体长差异不显著(P0.05)。试验C组饲料转化率显著高于B、D组(P0.05),A、B、D组饲料转化率差异不显著(P0.05)。试验C、D组总胆固醇含量显著高于对照组A组(P0.05);B、C、D组总胆固醇含量差异不显著(P0.05)。试验各组甘油三酯含量差异不显著(P0.05);B组总蛋白含量明显高于A、D两组(P0.05);C、D组总蛋白含量明显高于A组(P0.05);C组与B、D组总蛋白差异均不显著(P0.05)。在此日粮基础上,综合各项指标可得出,埋植褪黑激素后恢复期和冬毛生长期经产母水貂日粮中蛋氨酸的适宜添加水平为0.4%。     

6种热带亚热带豆科牧草抗寒性及营养品质比较

为了筛选华南地区适宜的优质冬季青饲料草种,本研究比较了旋扭山绿豆(Desmodium intortum)、大叶山蚂蟥(Desmodium laxiflorum)、异果山绿豆(Desmodium heterocarpum)、显脉山绿豆(Desmodium reticulatum)、糙毛假地豆(Desmodium heterocarpum var.strigosum)和柱花草(Stylosanthes guianensis)6种热带亚热带豆科牧草在广州越冬期的抗寒性及营养品质。结果表明,除柱花草外,其它5种豆科牧草均能保持青绿越冬,其中旋扭山绿豆和大叶山蚂蟥的叶绿素含量均显著高于其它牧草(P0.05)。旋扭山绿豆的净光合速率最高(P0.05),其次是大叶山蚂蟥(P0.05),因此这两种牧草具有相对较强的抗寒性;与其它牧草相比,旋扭山绿豆在冬季能保持较高的粗蛋白含量(15.99%~20.26%)(P0.05)以及较低的洗涤纤维(NDF 27.92%~30.89%、ADF 23.96%~27.06%)和缩合单宁含量(6.05~11.95mg·g~(-1))(P0.05),因而具有较高的营养价值。因此,旋扭山绿豆可以作为华南地区冬季豆科青饲料的潜在优选草种。     

不同NDF/NFE比的日粮对山羊瘤胃发酵参数影响的研究

利用4只(35±2.5)kg装有瘤胃瘘管的徐淮白山羊,采用拉丁方试验设计,饲喂NDF/NFE分别为1.46(A组)、1.2(5 B组)、1.0(3 C组)、0.8(2 D组)的4种日粮,研究其对瘤胃内环境参数的昼夜动态变化规律的影响。结果表明:①瘤胃pH随NDF/NFE的降低而降低,由A组的6.37降至D组的5.86;②乙酸浓度以B组最高,极显著(P<0.01)高于A、C和D组,A、C、D 3组则依次降低(P>0.05);丙酸浓度以B、D两组较高,极显著(P<0.01)高于A和C组;丁酸浓度随NDF/NFE降低而升高,D组最高,极显著(P<0.01)高于C和B组;总VFA浓度B组最高,极显著(P<0.01)高于D组,显著(P<0.05)高于A、C组;乙酸/丙酸比随NDF/NFE比的降低而减小,A组极显著(P<0.01)大于B、C和D组;③瘤胃氨态氮平均浓度随日粮NDF/NFE比的降低而升高,由A组的8.37mg/dL升至D组的13.71mg/dL。     

Circadian rhythm of calciotropic hormones,serum calcium,phosphorus and magnesium during the shortest and longest days of the year in horses in New Zealand

A study was conducted to determine the circadian rhythms and trends of vitamin D metabolites including 25‐hydroxyvitamin D₃, 25‐hydroxyvitamin D₂, 1,25‐dihydroxyvitamin D and parathyroid hormone, in addition to serum calcium, phosphorus and magnesium concentrations in horses over 48 h on the shortest and longest days of the year in 2013. Five healthy adult horses (Equus caballus) were on a constant pasture feeding regimen, and blood samples were collected from each horse every 3 h over a 48‐h period, starting at 07:00 PM on day one and finishing at 07:00 PM on day three, for the measurement of calciotropic hormones and electrolytes. There was a significant difference between the serum concentration of calciotropic hormones, iCa, tCa, P and tMg between the shortest (winter) and longest (summer) days of the year in horses. Serum concentration of 25OHD₃ was very low and mostly undetectable. Serum iCa, 1,25(OH)₂D and PTH concentrations clearly showed a circadian rhythm on the longest days of the year and serum tCa, P and tMg concentrations showed a diurnal pattern on the longest days (summer) of the year. None of the analytes showed any circadian rhythm on the shortest days (winter) of the year. The result of this study could have significant relevance to equine athletes travelling to international equestrian competitions and facing a huge time and seasonal differences that might affect their ability to adjust their circadian rhythms to new time zones.     

A free-choice intake of mineral blocks in beef cows during the grazing season and in winter

A herd of 25 beef cows were offered four types of mineral blocks (A, B, C, D) with a different Ca to P ratio (A 0.6:1, B 0.8:1, C 2:1 and D 3.6:1). The Mg content was identical in all blocks whereas the Na content was equal in B, C and D, while the Na content in A block was double. The mineral block intake was monitored for 1 year, which was broken down to the grazing period (Pa) and the winter period (Wi). The intake of pasture grass and winter forage was assessed and the feed chemical composition was analysed; based on the obtained values, a macroelement balance (for Ca, P, Mg, Na and K) was calculated.The results showed the forage diet met requirements for all the observed macroelements (except in Na). The macroelement intake from forage was considerably higher than from mineral blocks. There were significant seasonal (Pa versus Wi) differences in B and C blocks intake. The consumption of D block was relatively invariable all year round; block A was refused in both seasons though it contained the highest amount of highly deficient Na.It can be concluded that mineral content in forage meets beef cattle requirements for Ca, Mg and K, P content is just satisfactory, and Na content is insufficient. It appears that cows control, to some extent, the Ca to P ratio in their diet by choosing the appropriate type of mineral block. However, the preference or refusal of some types of mineral blocks regardless of the season suggests the influence of other factors affecting mineral block intake which were not the subject of our observation.     

Effect of nematode infections on growth performance of calves after stabling on commercial dairy farms

Growth performance of calves was assessed on 32 farms during winter housing. Nematode infection was measured by antibody titres, pepsinogen values, and faecal examinations. Half of each herd was treated with ivermectin after stabling. Treatment significantly increased growth rate by an average of +0.059 kg day-1 (P less than 0.01). The effect of treatment varied among herds from -0.078 to +0.210 kg day-1. Only a few of the infection parameters correlated weakly, but positively, to the effect of treatment on growth performance per herd. Untreated control groups showed very different growth rates among herds, ranging from 0.250 to 0.936 kg day-1. This was strongly correlated to several infection parameters. Groups with the highest values for the infection parameters gained approximately 50 kg less over a 4-month period during winter housing than groups with the lowest values for those infection parameters.