阿拉善荒漠草地8种牧草营养物质季节动态及营养均衡价评价

探讨了阿拉善荒漠草地珍珠柴(Salsola passerina)、霸王(Zygophyllum xanthoxylon)、红砂(Reaumuria soon-gorica)、绵刺(Potaninia mongolica)、梭梭(Haloxylon ammodendron)、盐爪爪(Kalidium foliatum)、沙鞭(Psammochloavillosa)和牛心朴子(Cynanchum komarovii)8种牧草营养物质含量的季节动态,并以粗蛋白质对其营养均衡价进行了比较。结果表明:8种牧草的粗蛋白质、粗脂肪、无氮浸出物、钙含量和钙磷比随着牧草的生长期呈先增加后降低的趋势,粗蛋白质含量6月最高,为7.86%~19.18%,1月最低,为5.25%~9.24%;粗脂肪、无氮浸出物、钙含量及钙磷比分别为0.81%~9.63%,26.19%~52.58%,0.12%~1.93%和0.86%~16.00%。粗纤维含量随植物生长呈降低趋势,且8种牧草的含量差异性较大,范围为9.56%~43.01%;粗灰分含量随生长期没有明显的季节动态规律;磷含量随牧草的生长而降低,范围0.04%~0.20%。牧草营养均衡价的评价表明:8种牧草营养均衡价(NB)依次为:梭梭绵刺珍珠柴霸王红砂盐爪爪牛心朴子沙鞭。     

Influence of ruminal and postruminal carbohydrate infusion on visceral organ mass and adipose tissue accretion in growing beef steers

Forty crossbred beef steers (243 +/- 2 kg of BW) with ruminal and abomasal infusion catheters were used to test 2 hypotheses: 1) visceral mass is responsive to energy input and site of carbohydrate (CHO) infusion and 2) rate and site of adipose accretion are dependent on site of CHO infusion and complexity. Treatments included a pelleted, forage-based, basal diet fed at 161 (LI) or 214 (HI) kcal of ME/(kg of BW(0.75) x d), LI plus ruminal (R-SH) or abomasal (A-SH) infusion of a partial starch hydrolysate (SH), and LI plus abomasal infusion of glucose (A-G). The basal diet was fed in 12 equal portions daily at 2-h intervals, with starch and glucose infused over a 22-h period at rates of 12.6 and 14.4 g/(kg of BW(0.75) x d). After 35 d of infusion, steers were slaughtered; and visceral organ and adipose mass, subcutaneous adipose thickness over the 5th and 12th rib, and LM intramuscular fat concentration were determined. Total intake energy (IE) increased (P = 0.0001) with ME intake. Dietary IE was similar between LI and CHO treatments, but total IE increased (P < 0.001) with CHO infusion. Greater dietary ME intake and CHO infusion increased or tended (P < or = 0.09) to increase final BW and HCW. As a percentage of empty BW, total stomach complex, rumen, omasum, liver, pancreas, and kidney weights were greater (P < or = 0.05) for HI vs. LI. Stomach complex, rumen, pancreas, and kidney weights as a percentage of empty BW were greater (P < or = 0.05) for R-SH vs. A-SH. Compared with ASH, A-G increased (P < or = 0.02) total and mucosal weights from the 10-cm sections of the ileum. Increases in rumen mass were associated with no change or an increase in rumen total and mucosal DNA concentrations. Greater dietary ME tended (P = 0.06) to increase subcutaneous fat thickness at the 5th rib but did not affect alimentary adipose accretion on an empty BW basis. Omental and total alimentary adipose weights were increased (P < or = 0.04) by A-G compared with A-SH. Although SH infusion did not alter adiposity, there was a consistent numerical pattern in total alimentary and subcutaneous fat depots with CHO infusion (A-G > ASH > R-SH). Our findings demonstrate that increasing ruminal CHO supply results in a disproportionate increase in rumen mass, whereas increasing small intestinal CHO supply does not alter gastrointestinal organ mass. Small intestinal energy in the form of glucose resulted in greater adipose accretion, particularly the omental depot.     

Frequency of pancreatic amyloid deposition in cats from south-eastern Queensland

Summary Stereological procedures were used to estimate the amount of amyloid deposition in the pancreatic islets of 83 cats from random sources in south-eastern Queensland. Most had only minor deposits of less than 20% of islet volume (median 9%), but deposits equal to more than 50% of the islet volume were found in 10% of the cats. Amyloid deposition in pancreatic islets was correlated with the age of the cat. Although similar observations have been made previously in cats from the USA, the frequency of amyloid deposition was higher in this population of cats from south-eastern Queensland.     

两种吡虫啉种衣剂在棉花和土壤中的残留动态研究

采用田间试验方法，研究了两种吡虫啉种衣剂在棉花和土壤中的残留消解动态，并对其在棉花上使用的安全性作出了评价。结果表明，两种吡虫啉种衣剂无论在棉株中或土壤中消解动态没有显著差异，其消解速度相当缓慢，有较长的药效。试验还表明，无论是推荐药量还是加倍药量．在正常使用条件下，都不会造成棉子残毒污染和土壤的残留积累。     

Risk Factors for Dairy Cow Mastitis in the Central Highlands of Ethiopia

This study, with the objective of assessing the effect of risk factors on dairy cow mastitis in the central highlands of Ethiopia, was undertaken between February and September 2001 in the urban and peri-urban areas of Addis Ababa, Ethiopia. A prevalence study and questionnaire survey were carried out simultaneously. Clinical examination of lactating udders and California mastitis test (CMT) determined clinical and subclinical mastitis, respectively. Risk factors for subclinical and clinical mastitis were identified from data on animals and farm management by chi-square analysis and subsequent logistic regression. Cows aged at least 8 years, with poor body condition, with at least 8 parities and in at least the eighth month of lactation had a significantly higher risk for subclinical mastitis (p < 0.05). The risk was reduced for cows up to their third parity in good body condition and for cows receiving dry cow therapy. Cows aged at least 4 years, or with at least 8 parities, cows in at least the fourth month of lactation, cows with poor body condition, leaking milk or previous udder infections had a significantly higher risk of clinical mastitis (p <0.05). The risk was reduced by the use of separate towels for udder cleaning and by drying off at the end of lactation. Most of the risk factors were in agreement with previous reports. However, stage of lactation and drying-off style were in contrast to others. Further research is needed to identify the interrelationship between production level, specific pathogens and management risk factors.     

Genetic screening of FecB,FecXG and FecXI mutations and their linkage with litter size in Barki and Rahmani sheep breeds

Characterization of fecundity genes offers the opportunity to improve production efficiency, and the consequent increase in litter size in livestock industry, through utilizing them in breeding programs. The main objective of this study was to detect the BMPR‐IB, BMP15 and GDF9 gene mutations and to investigate whether these mutations are associated with litter size in Egyptian sheep breeds. To achieve this goal, 73 adult ewes representing Barki (n = 33) and Rahmani (n = 40) breeds were used. Polymerase chain reaction–restriction fragment length polymorphism (PCR‐RFLP) screening approach was used to detect the presence of FecB, FecX^G and FecX^I mutations in the two selected breeds. Results of this study showed that the three different candidate gene mutations, namely FecB, FecX^G and FecX^I are not present among these selected populations of the Egyptian breeds. Further studies regarding other mutations and/or other genes, which may influence ovulation rate, should be carried out to determine the type and mode of inheritance of such genes in Egyptian sheep breeds.     

Occurrence of hydatidosis in slaughter buffaloes (Bos bubalis) and helminths in stray dogs in Kathmandu Valley, Nepal

The study aimed at identifying the occurrence of hydatidosis in slaughter buffaloes and helminth eggs, particularly Taenia spp. eggs in stray dogs' fecal samples in Kathmandu Valley, Nepal. The study period was from November, 2004 to April, 2005. A total of 500 buffalo carcasses in a slaughterhouse, at the riversides and individual butchers'sites were examined for the presence of hydatid cysts. The cyst fluid was collected and microscopically examined to determine if it was fertile or not. Of the 500 carcasses examined, 10.6% had hydatid cysts. Specifically, the slaughterhouse carcasses had a 6.7% occurrence of hydatid cysts, whereas those examined at riversides and individual butcher places had 10.0% and 12.7%, respectively. Distributions of the hydatid cysts by specific organs showed single occurrence of 6.4% in lungs, 2.4% in livers and 1.8% in both, livers and lungs. In a total of 53 infected buffaloes, 58.5% were fertile and 41.5% sterile cysts. Overall, 366 faecal samples from stray dogs were collected around buffaloes slaughtering areas (slaughterhouse and individual butcher places), riversides, garbage sites and temple sites. These samples were examined by formalin-ether concentration technique to investigate the presence of different helminth eggs. The total prevalence of Taenia, hookworms, Trichuris/Capillaria,Toxocara, Spirometra and Physaloptera eggs were 12.8%, 18.3%, 19.1%, 12.8%, 1.4% and 1.9%, respectively.     

The role of sand lances (Ammodytes sp.) in the Northwest Atlantic Ecosystem: A synthesis of current knowledge with implications for conservation and management

The American sand lance (Ammodytes americanus, Ammodytidae) and the Northern sand lance (A. dubius, Ammodytidae) are small forage fishes that play an important functional role in the Northwest Atlantic Ocean (NWA). The NWA is a highly dynamic ecosystem currently facing increased risks from climate change, fishing and energy development. We need a better understanding of the biology, population dynamics and ecosystem role of Ammodytes to inform relevant management, climate adaptation and conservation efforts. To meet this need, we synthesized available data on the (a) life history, behaviour and distribution; (b) trophic ecology; (c) threats and vulnerabilities; and (d) ecosystem services role of Ammodytes in the NWA. Overall, 72 regional predators including 45 species of fishes, two squids, 16 seabirds and nine marine mammals were found to consume Ammodytes. Priority research needs identified during this effort include basic information on the patterns and drivers in abundance and distribution of Ammodytes, improved assessments of reproductive biology schedules and investigations of regional sensitivity and resilience to climate change, fishing and habitat disturbance. Food web studies are also needed to evaluate trophic linkages and to assess the consequences of inconsistent zooplankton prey and predator fields on energy flow within the NWA ecosystem. Synthesis results represent the first comprehensive assessment of Ammodytes in the NWA and are intended to inform new research and support regional ecosystem‐based management approaches.