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1.
Summary Sixty dairy buffaloes (second to fourth lactation) from a large buffalo farm were used to compare the effects of single intramuscular injections of 100 µg gondadotrophin releasing hormone (GnRH), 250 µg GnRH or saline given on day 14post partum. The buffaloes had calved at the end of the breeding season (December). Milk samples for progesterone determination were taken at the time of injection and then three times a week either until first insemination or until around day 90post partum. GnRH given at 14 dayspost partum resulted in quicker completion of uterine involution, earlier resumption of ovarian activity, shorter intervals between calving and conception and a better first service conception rate in non-suckled dairy buffaloes. Differences between the results obtained by a GnRH dose level of 100 µg and 250 µg were non-significant. In the post-treatment period cases of prolonged luteal activity were common in all groups of buffaloes. Therefore the sequential administration of GnRH and prostaglandin is suggested for the management of post-partum reproductive activity in problem herds.
Desempeno Reproductivo De Bufalos Nili-Ravi Despues De Una Sola Inyeccion De GnRH Temprano Despues Del Post-Parto
Resumen Sesenta búfalos lecheros (segunda a cuarta lactancia) pertenecientes a un hato grande fueron utilizados para comparar los efectos de inyecciones intramusculares de 100 µg de GnRH, 250 µg y de solución salina, aplicadas 14 días después del parto. Los búfalos habian parido al final de la estación de pariciones (diciembre). Se tomaron muestras de leche para medir progesterona, en el momento de la inyección y después tres veces por semana hasta la primera inseminación, o hasta cerca de los 90 días post-parto. La GnRH administrada 14 días post-parto, dio como resultado una rápida involución uterina, más rápido retorno a la actividad ovárica, más cortos intervalos entre partos y concepción, y un mejor índice servicio-concepción en búfalos lecheros que no estaban amamantando. Los resultados de dosis de 100 µg y 250 µg no fueron significativos. En el período post-tratamiento, los casos de actividad luteal prolongada fueron comunes en todos los grupos de búfalos. Se sugiere entonces, la administración secuencial de GnRH y prostaglandina, parar el manejo de la actividad reproductiva post-parto en hatos problema.

Performances De Reproduction Du Buffle Nili-Ravi Apres Une Injection Unique PrecocePost Partum De Gonadotrophine (GnRH)
Résumé Soixante bufflesses laitières (de la seconde à la quatrième lactation), appartenant à une grande ferme d'élevage de buffles, ont été utilisées pour comparer les effets d'une injection unique intramusculaire de 100 µg de gonadotrophine, ou de 250 µg du même produit ou d'une solution de sérum physiologique. Les bufflesses avaient mis bas à la fin de la saison de reproduction soit en décembre. Des prélèvements de lait ont été effectués pour déterminer le taux de progestérone au moment de l'injection d'une part, puis trois fois par semaine d'autre part jusqu'à la première insémination ou aux alentours d'une période de 90 jours après le part. La gonadotrophine, libérée sous forme d'hormone (GnRH), injectée 14 jours après la mise bas a eu pour effet un retour complet plus rapide de l'involution utérine et des intervalles plus courts entre la mise bas et la conception ainsi qu'un meilleur taux de conception à la première monte chez les femelles laitières non allaitantes. Les différences entre les résultats obtenus par une dose de 100/µg ou de 250/µg de gonadotrophine (GnRH) n'étaient pas significatives. Pendant la période post-thérapeutique, des cas d'activité lutéale prolongée ont été courants dans tous les groupes de bufflesses. En conséquence, l'administration séquentielle de GnRH et de prostaglandine est conseillée pour contrôler l'activité post-partum de reproduction dans les troupeaux qui présentent des problèmes de cet ordre.
  相似文献   
2.
This experiment aimed to examine the effect of periodical application of bioactive peptides derived from cottonseed (BPC) in comparison with using sub-therapeutic doses of lincomycin and the excessive inclusion of vitamin E on performance, immunity, total antioxidant capacity of serum and intestinal morphology of broiler chickens. A total of 240 one-d-old male broiler chicks with similar initial weight (Ross strain) were randomly assigned to 6 groups (8 chicks/pen): non-treated group (basal diet), basal diet supplemented with 2 mg/kg lincomycin, basal diet supplemented with 50 IU vitamin E, basal diet supplemented with 6 g BPC/kg in starter period, basal diet supplemented with 6 g BPC/kg in starter and grower periods and basal diet supplemented with 6 g BPC/kg throughout the whole experiment. The highest final body weight was obtained in the group supplemented with BPC in starter and grower periods. In the finisher phase, broilers fed the diet containing BPC in the starter period and in the whole trial had significantly (P < 0.05) better feed conversion ratios (FCR). Jejunal villus height was significantly elevated in broilers supplemented with antibiotic (P < 0.001), furthermore it tended to be greater in broilers fed BPC in the starter period. The jejunal villus height-to-crypt depth ratio was significantly (P < 0.01) higher in broilers fed the diet containing antibiotic in comparison to other groups. Humoral immune response against Newcastle disease vaccine tended to be elevated in broilers fed the diet containing BPC in the whole trial (P > 0.05). Broilers supplemented with BPC in starter and grower, and in the whole trial had significantly (P < 0.05) higher antibody titers against sheep red blood cells (SRBC). The highest total antioxidant capacity was obtained in broilers supplemented with the excessive level of vitamin E, furthermore it tended to improve in broilers fed the diet containing BPC in the whole trial. In summary, the results of the study indicated that addition of BPC in broiler diets in the whole trial could improve FCR, immune responses and total antioxidant activity of serum, and BPC could be used in broiler diets as an alternative to in-feed antibiotics.  相似文献   
3.
Controlled-release formulations of 14C-labelled thiobencarb herbicide were prepared in calcium alginate using kaolin as an inexpensive filler. The rates of release of the herbicide from these and from a commercial granular formulation were studied in static distilled water contained in open and closed vessels. The rate of release of the herbicide was much higher from the commercial formulation than from the controlled-release formulations. Increasing the proportion of kaolin to calcium alginate in controlled-release formulations reduced the rate of release of the herbicide. There was a significant loss of thiobencarb-related radioactivity from the water solution when the vessels containing the solutions were left uncovered and exposed to light. The loss of the herbicide seemed to be due to degradation and evaporation.  相似文献   
4.
Biological samples were collected from dogs in resource-limited communities in the North-West and Gauteng Provinces of South Africa to assess the prevalence of helminth parasitism. These samples included adhesive tape peri-anal skin swabs and fresh faecal samples for helminth examination, and thick and thin blood films (smears) and whole-blood samples in anticoagulant for examination of filarial nematode microfilariae and haemoprotozoa. The eggs of Ancylostoma caninum, Toxocara canis, Toxascaris leonina, Dipylidium caninum and taeniids were identified. None of the blood samples and smears tested positive for microfilariae of Dirofilaria immitis or Dipetalonema spp. or for haemoprotozoa. The adhesive tape swabs were negative for cestode eggs and segments. Most of the helminth parasites identified in this study are zoonotic and consequently are regarded as a public health hazard.  相似文献   
5.
Telomere shortening in normal somatic cells has been proposed as a major barrier to unlimited cellular proliferation. Telomerase is an enzyme capable of maintaining telomere length, and thus bypassing this barrier. In human beings, telomerase activity is restricted to cancer cells and cells of stem or germ cell lineages. Dogs represent a potentially useful clinical model for the development of telomerase‐based therapies because telomerase activity is also restricted to cancer cells and stem cells in this species. We examined the ability of telomestatin to inhibit telomerase activity in telomerase‐positive D17 and CMT7 canine cancer cell lines. At a concentration of 2 μM, telomestatin treatment resulted in a decrease in telomerase activity, telomere shortening, growth inhibition and apoptosis in telomerase‐positive cancer cells. These effects were not seen in telomerase‐negative skin fibroblasts or negative controls. These results confirm that telomestatin specifically inhibits telomerase activity in canine cancer cells and strengthens the usefulness of dogs as a model for testing telomerase‐based therapies.  相似文献   
6.
7.
In order to use rice straw as forage in livestock feeding, the effects of steam-treated rice straw (at 15.5 kgf/cm2 for 120 s) feeding on growth performance, plasma volatile fatty acid profile, and nutrient digestibility of goats were determined. Twenty male goats (18.69?±?0.34 kg) were used in an 84-day trial. The goats were divided into four groups of five goats each to receive steam-treated (STRS) or untreated (UTRS) rice straw diet under closed house (CH) and open house (OH) systems. The results revealed that the goats fed with STRS had significantly higher dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fiber (NDF), and acid detergent fiber (ADF) digestibility; similarly, the average daily weight gain and feed conversion ratio were higher for STRS groups under both CH and OH systems than those for UTRS. The plasma protein and insulin in STRS and cholesterol in UTRS groups was higher (P?P?>?0.05) at 30 days. The plasma amylase, lipase, T3, T4 and glucagon at 30 and 60 days were not different (P?>?0.05) among the groups. The plasma acetate, propionate, butyrate, and total volatile fatty acid were higher (P?P?>?0.05) on these parameters. It could be concluded that steam treatment of rice straw at 15.5 kgf/cm2 for 120 s increased apparent nutrient digestibility, hence increased the growth and feed efficiency of growing goats.  相似文献   
8.
研究不同时期斑茅产量及其化学组分的变化。结果表明:斑茅生物质产量在11月达到最高,其后开始下降;整个生长发育过程中茎叶生物质产量比呈现上升趋势;含水量随生长发育的进行显著降低;叶片灰分含量全年最低为5月,从10月份开始显著增加,至12月份达到最高。茎秆灰分含量略低于叶片,全年最低为10月,最高为7月,变化幅度不大。叶片中木质素含量全年由高到低排列顺序为12月11月9月10月7月8月6月;茎秆中木质素含量全年由高到低排列顺序为12月11月9月7月8月10月6月。10月份茎秆含水量低,灰分含量最低,热值较高,结合产量和燃料品质考虑其更适于直接燃烧,而9月份叶片则更加适于作为生物转化的材料。  相似文献   
9.
Present study is focused on the preparation of two layers composite wound dressing for drug release. The outer layer is made of hydrogel which contains of drug and the core layer is made of fabric. The two layers structure of composite dressing is formed by grafting of polyacrylamide-co-acrylic acid hydrogel on cotton fabric using ammonium per sulphate (APS) as chemical initiator and polyethylene glycol (PEG) as crosslinker. The major factors affecting graft copolymerization of hydrogel on cotton fabric are optimized by varying concentration of monomers & initiator, reaction temperature and addition time of crosslinker. Maximum grafting of hydrogel is obtained at 5 % (w/v) APS and 15 % acrylamide/acrylic acid (1:1 w/w ratio) concentration. The FTIR spectra of composite dressing shows characteristics peak of acrylic acid and acrylamide. The composite wound dressing material is loaded with model drug bovine serum albumin (BSA) and drug release behaviour is studied at different pH. The dressing shows drug release in different pH with maximum release of drug in acidic medium.  相似文献   
10.
The concentration and size distribution of bacterial and fungal aerosol was studied in 15 houses. The houses were categorized into three types, based on occupant density and number of rooms: single room in shared accommodation (type I), single bedroom flat in three storey buildings (type II) and two or three bedroomed houses (type III). Sampling was undertaken with an Anderson six-stage impactor during the summer of 2007 in the living rooms of all the residential settings. The maximum mean geometric concentration of bacterial (5,036 CFU/m3, ± 2.5, n?=?5) and fungal (2,124 CFU/m3, ± 1.38, n?=?5) aerosol were in housing type III. The minimum levels of indoor culturable bacteria (1,557 CFU/m3, ±1.5, n?=?5) and fungal (925 CFU/m3, ±2.9, n?=?5) spores were observed in housing type I. The differences in terms of total bacterial and fungal concentration were less obvious between housing types I and II as compared to type III. With reference to size distribution, the dominant stages for culturable bacteria in housing types I, II and III were stage 3 (3.3–4.7 μm), stage 1 (7 μm and above) and stage 5 (1.1–2.1 μm), respectively. Whereas the maximum numbers of culturable fungal spores were recovered from stage 2 (4.7–7 µm), in housing type I, and from stage 4 (2.1–3.3 μm) in both type II and III houses. The average geometric mean diameter of bacterial aerosol was largest in type I (4.7 μm), followed by type II (3.89 μm) and III (1.96 μm). Similarly, for fungal spores, type I houses had the highest average mean geometric diameter (4.5 μm), while in types II and III the mean geometric diameter was 3.57 and 3.92 μm, respectively. The results indicate a wide variation in total concentration and size of bioaerosols among different residential settings. The observed differences in the size distributions and concentrations reflect their variable airborne behaviour and, as a result, different risks of respiratory exposure of the occupants to bioaerosols in various residential settings.  相似文献   
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