利用微量元素来最大限度地促进生产

在过去的15年中,肉鸡养殖业中的遗传改良是显著的.一个领先的种鸡公司声称仅在这一时期其产品的饲料转化率就提高了35个百分点,活重肉产量提高了4.5%.实际生产中这些遗传改良有可能还在继续.这些改善是合乎人们需要的,因此,通过营养和管理手段,特别是在亲本饲养方面,来充分发挥这种遗传潜力,就非常有挑战性.     

Medial patellar ligament splitting for the treatment of upward fixation of the patella in 7 equids

OBJECTIVE: To describe a surgical technique for splitting the proximal third of the medial patellar ligament (MPL) in horses and ponies with upward fixation of the patella (UFP), and to report outcome. STUDY DESIGN: Prospective clinical study. SAMPLE POPULATION: Four horses and 3 Shetland ponies. METHODS: With ultrasound guidance, the proximal third of the MPL was split by percutaneous use of a no. 15 scalpel blade. The rationale for this surgical procedure was to induce a localized desmitis with subsequent ligament thickening. No anti-inflammatory drugs were administered, and horses and ponies were exercised the day after surgery. Clinical, radiographic and ultrasonographic follow-up evaluation was obtained. RESULTS: No short-term or long-term complications were observed, and no patients had clinical signs of UFP after surgery. This clinical effect was attributed to a 2- to 3-fold increase in size of the proximal part the MPL from an induced localized desmitis. CONCLUSIONS-Percutaneous splitting of the proximal third of the MPL resolved UFP in equids. CLINICAL RELEVANCE: Splitting of the proximal third of the MPL is effective for treatment of UFP and allows rapid return to normal activity.     

Ultrasonograhic and histopathological features of atypical interstitial (Leydig) cell tumors in two cryptorchid horses

This article describes atypical interstitial (Leydig) cell tumors in two cryptorchid horses. Ultrasonography allowed accurate localization of the cryptorchid testicles. Ultrasonographic features of the tumor are also presented and may be of value for the clinical diagnosis.Histopathological evaluation of testicular tissue after cryptorchidectomy revealed atypical evolving interstitial (Leydig) cell tumors. Clinically, the tumors reported here appear to have several similarities with the interstitial (Leydig) cell tumors described in the literature, which in most cases appear to be (1) cryptorchidism–induced tumors, (2) often benign and not enlarged, and (3) often associated with aggressive behavior. Although generally considered to be uncommon, equine testicular neoplasms may occur more frequently than previously thought. The use of ultrasonography may improve diagnosis.     

Cholinergic receptors of the central nervous system of insects

Concentrated particulate preparations were made from housefly heads and the nerve cords of the American and Madagascar cockroaches. Macromolecules present in these preparations bound ³H-nicotine reversibly and with high affinities (3, 1.1, and 1.5 μM, respectively). Binding of ACh to the macromolecules in the preparation of houseflies and Madagascar cockroach was determined by inhibition of ³H-nicotine binding, and was found to be of much lower affinity than that of nicotine.There was a 2 × purification of the nicotine-binding macromolecules in this particulate preparation of housefly heads as compared to an earlier preparation of supernatant of 100,000g. Nicotine binding to this particulate preparation was blocked also by d-tubocurarine and atropine demonstrating the nicotinic and muscarinic nature of these nicotine-binding macromolecules. Prior exposure of the preparation to trypsin and chymotrypsin reduced nicotine binding by 58 and 68%, respectively.The relationship of these nicotine and ACh binding macromolecules to ACh-receptors is discussed.     

Impaired thermosensation in mice lacking TRPV3, a heat and camphor sensor in the skin

Environmental temperature is thought to be directly sensed by neurons through their projections in the skin. A subset of the mammalian transient receptor potential (TRP) family of ion channels has been implicated in this process. These "thermoTRPs" are activated at distinct temperature thresholds and are typically expressed in sensory neurons. TRPV3 is activated by heat (>33 degrees C) and, unlike most thermoTRPs, is expressed in mouse keratinocytes. We found that TRPV3 null mice have strong deficits in responses to innocuous and noxious heat but not in other sensory modalities; hence, TRPV3 has a specific role in thermosensation. The natural compound camphor, which modulates sensations of warmth in humans, proved to be a specific activator of TRPV3. Camphor activated cultured primary keratinocytes but not sensory neurons, and this activity was abolished in TRPV3 null mice. Therefore, heat-activated receptors in keratinocytes are important for mammalian thermosensation.     

The effects of slaughter weight on chemical composition,physical properties,and fatty acid profile of musculus longissimus dorsi in Holstein bulls

Tropical Animal Health and Production - This study was conducted to investigate the effects of slaughter weight on chemical composition, physical properties, and fatty acid profile of musculus...     

Occurrence of Campylobacter species from broiler chickens and chicken meat in Malaysia

Tropical Animal Health and Production - Campylobacter is reported as a major cause of foodborne illness worldwide. Consumption of contaminated chicken meat is considered a significant risk factor...     

Improved resistance against Botrytis cinerea by grapevine-associated bacteria that induce a prime oxidative burst and phytoalexin production

Bacteria such as Pantoea agglomerans (Pa-AF2), Bacillus subtilis (Bs-271), Acinetobacter lwoffii (Al-113), and Pseudomonas fluorescens (Pf-CT2), originating from the vineyard, can induce defense responses and enhance resistance of grapevine against the fungal pathogen Botrytis cinerea. The perception of these bacteria by plant cells or tissues in relation to their activities remains unknown. In this study, we examined the relationships between the activity of each bacterium to induce or prime some defense responses, and its effectiveness to induce resistance in grapevine against B. cinerea. We showed that all selected bacteria are capable of inducing early oxidative burst and phytoalexin (trans-resveratrol and trans-ε-viniferin) production in grapevine cells and leaves. Pf-CT2 and Al-113 induced higher H(2)O(2) and trans-resveratrol accumulations, and were able to further prime plants for accelerated phytoalexin production after B. cinerea challenge. These two bacteria were also the most effective in inducing local and systemic resistance. A similar level of induced resistance was observed with live Pa-AF2 which also induced but not primed a greater accumulation of trans-resveratrol. However, Bs-271, which was less effective in inducing resistance, induced a lower trans-resveratrol synthesis, without priming activity. Treatment of grapevine cells with growing medium or crude extract of the bacteria quickly and strongly enhanced oxidative burst compared with the live bacteria. However, both treatments resulted in comparable amounts of phytoalexins and induced local and systemic resistance to B. cinerea as compared with those induced by living bacteria, with extracts from Pf-CT2 and Al-113 being the most effective. Together, these results indicate that induced resistance can be improved by treatment with bacteria or derived compounds which induced or primed plants for enhanced phytoalexin accumulation.