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951.

In the next two decades, the world population will increase significantly; the majority in the developing countries located in the tropics of Africa, Asia, Latin America, and the Caribbean. To feed such a population, it is necessary to increase the availability of food, particularly high-value animal protein foods produced locally, namely meat and dairy products. Dairy production in tropical regions has a lot of growth potential, but also poses a series of problems, particularly as dairy production systems were developed in temperate countries and in most cases are difficult to implement in the tropics. Drawbacks include hot weather and heat stress, the lack of availability of adequate feeds, poor infrastructure, and cold chain and the competition with cheap imports from temperate countries. This position paper reviews the major drawbacks in dairy production for the five major dairy species: cattle, water buffalo, sheep, goat, and camel, as well as the future trends in research and development. It also concerns the major trends in reproduction and production systems and health issues as well as environmental concerns, particularly those related to greenhouse gas emissions. Tropical Animal Health and Production now launches a topical collection on Tropical Dairy Science. We aim to publish interesting and significant papers in tropical dairy science. On behalf of the editorial board of the Tropical Animal Health and Production, we would like to invite all authors working in this field to submit their works on this topic to this topical collection in our journal.

  相似文献   
952.
This study evaluates the analgesic efficacy of low-dose hydromorphone administered via pharmacopuncture at Governing Vessel 20 (GV20) for postoperative pain management following canine ovariohysterectomy. Fifty clinically healthy female dogs undergoing ovariohysterectomy were allocated to receive hydromorphone [0.1 mg/kg body weight (BW)] intramuscularly (IM, n = 25) or hydromorphone (0.01 mg/kg BW) pharmacopuncture at GV20 (GV, n = 25) following extubation. This was a prospective, blinded, randomized clinical trial. Pain and sedation scores were evaluated using the Glasgow Composite Measure Pain Scale Short Form (CMPS-SF) at 1, 2, 3, 4, and 12 hours following study treatment. Time of treatment failure (CMPS-SF ≥ 6/24) was recorded and analyzed using Kaplan-Meier survival analysis. Patient demographics and duration of surgery and anesthesia were analyzed using the appropriate unpaired Student’s t-test. The Glasgow CMPS-SF and sedation score were analyzed using a repeated measures 2-way analysis of variance (ANOVA) followed by Bonferroni post-test where appropriate. Significance was set a P < 0.05. There were no significant differences in patient demographics, anesthesia and surgery duration, and study treatment failure. The Glasgow CMPS-SF scores were significantly higher for IM compared with GV [2 (0 to 8) versus 1 (0 to 6), respectively; P = 0.044] at 4 hours. Sedation scores were significantly higher for IM compared with GV at 2 [2 (1 to 3) and 1 (1 to 3), respectively; P = 0.0004] and 4 [1 (1 to 3) and 1 (1 to 2), respectively; P = 0.03] hours. Pharmacopuncture with low-dose hydromorphone provided adequate postoperative analgesia in dogs undergoing ovariohysterectomy with reduced sedative effects. Pharmacopuncture is a good alternative in dogs when reduced dosing of opioids is recommended.  相似文献   
953.
Summary The existence of structural differentiation between genomes in section Arachis of the genus Arachis has important implications in the utilization of diploid wild species in this section as a germplasm resource. Maximum expression of desirable characters may not be achieved unless tetrasomic dose levels can be achieved. Possible breeding strategies discussed include natural and induced gene exchange between genomes and chromosome substitution which could be brought about by manipulation of ploidy level and where appropriate the use of ionizing radiation. Such strategies could be tested in the improvement of resistance to the Cercospora leafspots.Paper number 5561 of the Journal Series of the North Carolina Agricultural Experimental Station, Raleigh, NC 27650.  相似文献   
954.
955.
956.

Objective

To determine whether intratesticular injection of an alfaxalone–lidocaine combination can induce anesthesia and provide a rapid recovery in piglets undergoing surgical castration.

Study design

Randomized experimental study.

Animals

A group of 30 male piglets, aged 2–10 days, weighing 1.3–4.6 kg.

Methods

Animals were randomly divided into three equal groups for intratesticular administration of alfaxalone + lidocaine: high dose (group HD; 8 mg kg–1 + 2.5 mg kg–1), medium dose (group MD; 6 mg kg?1 + 2 mg kg?1) and low dose (group LD; 4 mg kg?1 + 1.5 mg kg?1). Induction and recovery times, movement and vocalization were recorded. Pulse rate (PR), oxygen saturation, respiratory rate (fR), rectal temperature, blood pressure and end-tidal carbon dioxide were recorded until recovery.

Results

Induction time did not differ significantly among groups (p = 0.19); mean time of 2.2, 3.3 and 3.7 minutes for HD, MD and LD, respectively. Recovery time to sternal recumbency was significantly faster in LD compared with HD and MD (p = 0.005). Time to standing was mean 34.1, 31.6 and 29.6 minutes for HD, MD and LD, respectively (p = 0.58). Incidences of movement and vocalization during the castration procedure were decreased in HD and MD compared with LD, but were not statistically different. There were no differences in the physiologic data among the groups except for PR, which decreased in all three groups (p < 0.05), and fR, which increased in MD and LD (p < 0.05).

Conclusions and clinical relevance

The alfaxalone–lidocaine combinations investigated in this study induced deep sedation in all piglets. Physiologic data remained within clinically acceptable ranges, suggesting that this drug combination by intratesticular injection prior to castration in neonatal piglets is well tolerated. The authors recommend the alfaxalone (6 mg kg?1) + lidocaine (2 mg kg?1) dose.  相似文献   
957.
Herbage from forage rape ( Brassica napus cv. Lair), harvested in the autumn, was separated into different morphological components and offered ad libitum to weaned lambs and adult sheep in two indoor pen-feeding experiments. In vivo. digestibility and the voluntary intake of herbage components were measured and related to chemical composition and in vitro digestibility. The organic matter digestibility of all plant components, especially of petiole, was high; lamina, 0·847: petiole, 0·892; upper stem. 0·865; lower stem, 0·771. Lambs and adults digested 'leaf' (0·83) vs 0·846) or 'stem' (0·782 vs 0·789) equally well. Both lambs and adults ate much less of the components or of whole crop than would be predicted with grass crops of similar digestibility or fibre content. With the exception of lamina, intake was closely related positively to digestibility and negatively lo fibre content. Low intakes of lamina were associated with high concentrations of glucosinolates. In vitro digestibility values obtained on small samples of forage show that the process is adequate for the prediction of in vivo digestibility.  相似文献   
958.
The induction and differentiation of feeding structures (syncytia) of the cyst nematode Heterodera schachtii in roots of Arabidopsis thaliana is accompanied by drastic cellular modifications. We investigated the formation of cell wall openings which occurred during syncytium differentiation. At the beginning of syncytium induction, a callose-like layer was deposited inside of the wall of the initial syncytial cell (ISC). First wall dissolutions developed by gradual widening of plasmodesmata between the ISC and neighbouring cells. As a general thickening of syncytial cell walls blocked existing plasmodesmata, other large openings were formed by enzymatic dissolution of intact walls by putative cellulase activity.  相似文献   
959.
960.
1. The role of beta2-agonist and of cAMP in chick skeletal muscle proteolytic pathways and protein synthesis was investigated using an in vitro preparation that maintains tissue glycogen stores and metabolic activity for several hours. 2. In extensor digitorum longus (EDL) muscle total proteolysis decreased by 15 to 20% in the presence of equimolar concentrations of epinephrine, clenbuterol, a selective hbetaagonist, or dibutyryl-cAMP. Rates of protein synthesis were not altered by clenbuterol or dibutyryl-cAMP. 3. The decrease in the rate of total protein degradation induced by 10(-5)M clenbuterol was paralleled by a 44% reduction in Ca2+-dependent proteolysis, which was prevented by 10(-5)M ICI 118.551, a selective fbeta2antagonist. 4. No change was observed in the activity of the lysosomal, ATP-dependent, and ATP-independent proteolytic systems. Ca2+-dependent proteolytic activity was also reduced by 58% in the presence of 10(-4)M dibutyryl-cAMP or isobutylmethylxanthine. 5. The data suggest that catecholamines exert an inhibitory control of Ca2+-dependent proteolysis in chick skeletal muscle, probably mediated by fbeta2adrenoceptors, with the participation of a cAMP-dependent pathway.  相似文献   
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