大蒜素及其在畜禽生产中的应用进展

大蒜素是一种绿色环保药物和环保型绿色饲料添加剂,在畜禽养殖中应用十分广泛.本文综述了大蒜素的化学成分和理化特性、功能特点及其在畜禽养殖中的应用情况,并对其应用前景作了分析.     

磺胺嘧啶原料药生产设备的清洁验证

为验证磺胺嘧啶原料药生产设备清洁方法的有效性，从验证合格标准、取样回收率、检测方法、设备清洁后的贮存期限等方面对清洁方法进行了研究。试验证明，磺胺嘧啶原料药生产设备的清洁方法是有效的，按此方法清洁的设备其贮存期限为14天。     

Erythrocytes

Most anemias can be classified using the reticulocyte count, PCV, MCV, and MCHC. Regenerative anemias are characterized by reticulocytosis. Polychromasia and increased MCV usually are present. Hemolytic mechanisms and hemorrhage should be considered in a systemic evaluation of the blood and the patient. In animals with chronic external blood loss, a microcytic, hypochromic anemia develops secondary to iron deficiency. Nonregenerative anemias generally are characterized by normocytic, normochromic erythrocytes and the lack of reticulocytosis. Patients with nonregenerative anemia should be evaluated for chronic inflammation or neoplasia, renal disease, endocrine insufficiency, or hypoplasia of the bone marrow.     

Idiopathic immune-mediated hemolytic anemia in a calf.

Severe anemia was found in a 4-month-old heifer, which was admitted with a 1-day history of anorexia, signs of depression, and recumbency. A diagnosis of immune-mediated hemolytic anemia (IHA) was made on the basis of a Coomb's titer of 1:128 and decreased resistance to osmotic stress, as determined by an RBC fragility test. Anaplasmosis and leptospirosis were ruled out as possible causes of the IHA. Other causes of hemolytic anemia, including intoxication by copper, water, Brassica spp, or drugs were ruled out. Therefore the IHA was considered idiopathic. Treatment consisted of supportive therapy, oxytetracycline, and dexamethasone. After 60 days of treatment, CBC, Coomb's test result, and RBC fragility were within normal limits.     

Spleen cell population changes and hemolytic anemia in F344 rats with large granular lymphocyte leukemia

A spontaneous large granular lymphocyte leukemia from a F344 rat was transplanted to 36 syngeneic recipients to study the interactions among leukemia, T lymphocytes, and the development of immunemediated hemolytic anemia. Six rats were euthanatized at biweekly intervals, and spleen weight, total spleen cellularity, and differential spleen cell counts were correlated with hemograms and osmotic fragility. Sequential changes in splenic architecture were correlated with hematologic parameters. Monoclonal antibodies defining all T lymphocytes (W3/13), T helper-inducer cells (W3/25), and T suppressor cells (OX-8) were used to identify T cells in immunocytochemical techniques on spleen sections, as well as in fluorescence activated cell sorter analysis of spleen cell suspensions. The onset of hemolytic anemic at 7 weeks after transplantation coincided with the first detection of tumor cells in the spleen and peripheral blood. Tumor cells first accumulated in the marginal zones, and then they infiltrated the red pulp sinusoids. Although the leukemia caused dispersion of the splenic lymphoid tissue, there was no significant lymphopenia, and the relative number of helper (W3/25+) and suppressor (OX-8+) lymphocytes did not change. Because the induction of anemia was a relatively early event in splenic involvement, we concluded that anemia was unrelated to disruption of lymphoid architecture; furthermore, it does not appear to be caused by changes in the numbers of regulatory T lymphocytes.     

Bovine leukocyte adhesion deficiency in Holstein cattle.

Two Holstein heifers with persistent and recurrent infections including ulcerative gingivitis, periodontitis, pneumonia, loss of teeth and stunted growth associated with marked neutrophilia were evaluated clinically and for neutrophil function, CD18 expression on neutrophils and CD18 genotype analysis by DNA-polymerase chain reaction (PCR) test. Adherence to nylon fibers and phagocytic activity of neutrophils from affected animals were significantly (p < 0.05) impaired as compared with those of controls. Neutrophils from affected heifers had decreased chemiluminescent (CL) responses when stimulated with opsonized zymosan, compared with those of controls. In contrast, neutrophils from affected heifers produced increased CL responses when stimulated with latex beads and phorbol myristate acetate compared with those of controls. The clinical findings, functional leukocyte abnormalities, deficiency in expression of CD18 on neutrophils, and the D128G mutation detected by DNA-PCR testing of affected heifers demonstrated that these heifers have bovine leukocyte adhesion deficiency (BLAD). Although both animals were confirmed to be homozygotes for BLAD by DNA-PCR test, they had differences in clinical, hematological and neutrophil functional characteristics.     

Malocclusions in the koala (Phascolarctos cinereus)

Malocclusions are a misalignment or incorrect positioning of the teeth when the upper and lower jaws close. These are poorly described in the koala and can result in irregular mastication which can have lifelong effects on body condition and oral health. A total of 370 koalas from two populations in Queensland (295) and one in South Australia (75) were examined for malocclusions. The prevalence of malocclusions in South Australian free‐ranging koalas, captive Queensland koalas and Queensland free‐ranging koalas was 39% (44), 30% (29) and 22% (29) respectively. Four types of malocclusion were identified based on severity of misalignment of the incisor/canine region, types 1, 2, 3 and 4. Maxillary overbite measurements of the molariform teeth were determined and these anisognathic values were then used to describe malocclusions within familial relationships in captive colonies. Captive koalas with a malocclusion had narrower mandibular width that ranged between 0.5 and 1% less than the normal measurements. The specific malocclusions reported in this study affected individuals by leading to tooth rotation, mobility and erosion with inefficient mastication of food and vegetation compaction. These changes increased the oral cavity pathology, by placing animals at risk of periodontal disease. There was evidence of familial links to malocclusion types in captive animals. Therefore captive breeding recommendations should consider known koala malocclusion traits to minimise their effect on future generations.     

Influence of Osteopontin in Bovine Uterine Tube Fluid on Sperm Binding and Fertilization in RCA-1 Lectin-treated Oocytes

This study was conducted to determine the effect of pre‐exposure of oocytes to Ricinus communis (RCA‐1) lectin and osteopontin (OPN) in uterine tube fluid (UTF) on in vitro sperm–egg binding and fertilization. In vitro‐matured bovine oocytes were incubated (39°C, 5% CO₂ in air) for 2 h in the following treatments: (i) 500 μl of fertilization medium (FM); (ii) 250 μl of FM with 0.25 ml of non‐luteal ampullary uterine tube fluid (NLAUTF); (iii) 250 μl of FM with 250 μl of NLAUTF and 4 μl of RCA‐1 lectin; (iv) 250 μl of FM with 250 μl of NLAUTF, a rabbit polyclonal antibody (1:200) against purified bovine milk OPN, and RCA‐1 lectin; (v) 500 μl of FM and RCA‐1 lectin. Following incubation, oocytes were washed, placed in FM with 2 μg heparin, and incubated with 1 × 10⁵ frozen–thawed spermatozoa per 10 oocytes. Oocytes used to assess sperm binding were stained with Hoescht 33342, and the number of sperm bound per zona pellucida counted. The remaining oocytes were fixed in acid alcohol, stained with 1% acetate‐orcein and observed to determine the presence of pronuclei. More sperm bound to the zona pellucida (mean ± SEM) when oocytes were incubated in treatment 3 (59.0 ± 5.5) than in treatments 2 (46.4 ± 5.6), 4 (18.1 ± 5.4), 5 (33.4 ± 5.6) or 1 (32.5 ± 5.6). More oocytes were fertilized when incubated in treatment 3 (91% ± 3.0) than in 2 (84% ± 3.0), 4 (40% ± 3.0), 5 (77% ± 3.0) or 1 (76% ± 3.0). As in previous studies, this study suggests that RCA‐1 lectin enhances binding of UTF‐derived OPN to bovine oocytes, resulting in increased sperm–egg binding and fertilization in vitro and a possible role in fertilization.     

Sex-related responses to vitamin B12 and trace element supplementation in prime lambs

Bodyweight, plasma vitamin B12 and blood selenium concentrations were monitored in prime lambs given different forms of supplementation at 2 sites in separate years. At the first site treatment groups comprised control, vitamin B12 injection, selenium given orally and a combination of vitamin B12 and selenium. At the second site cobalt and selenium supplied in a glass bullet was compared with an untreated group. Significant sex-related responses were observed to treatment in terms of bodyweight and at site 2 in plasma vitamin B12 concentrations. A marked bodyweight response to glass bullet supplementation was observed in castrated male lambs but not in ewe lambs. These studies show that sex differences should be considered when investigating trace element deficiencies.