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11.
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This article examines the efforts by the Northwest Treeplanters and Farmworkers United union to organize Mexican migrant farmworkers in the Willamette Valley. It focuses on the union's 1995 organizing campaign of strawberry picker?s, the largest campaign in the history of Pacific Northwest agriculture. To provide context for the union's efforts, the article develops the historical role and changing nature of Oregon agriculture, sketches the politics of agriculture in the state, and describes the industry's labor system. The article concludes that significant gains for strawberry pickers were made during the 1995 campaign; the long-term consolidation of those gains remains to be demonstrated.  相似文献   
13.
DARPP-32, a dopamine- and adenosine 3',5'-monophosphate (cAMP)-regulated phosphoprotein (32 kilodaltons in size), is an obligate intermediate in progesterone (P)-facilitated sexual receptivity in female rats and mice. The facilitative effect of P on sexual receptivity in female rats was blocked by antisense oligonucleotides to DARPP-32. Homozygous mice carrying a null mutation for the DARPP-32 gene exhibited minimal levels of P-facilitated sexual receptivity when compared to their wild-type littermates. P significantly increased hypothalamic cAMP levels and cAMP-dependent protein kinase activity. These increases were not inhibited by a D1 subclass dopamine receptor antagonist. P also enhanced phosphorylation of DARPP-32 on threonine 34 in the hypothalamus of mice. DARPP-32 activation is thus an obligatory step in progestin receptor regulation of sexual receptivity in rats and mice.  相似文献   
14.
Sera from hosts infected with a variety of nematodes were examined for the presence of antibodies against nematode acetylcholinesterase (AChE). Antibodies were detected in the serum from hosts infected with Oesophagostomum spp., Ostertagia spp. and Trichostrongylus spp., but not in serum from hosts infected with Cooperia pectinata or Haemonchus spp., Toxocara spp. or Trichuris vulpis. In those infections in which anti-AChE antibodies were found, some individual animals failed to produce detectable antibodies. The enzyme appeared to possess antigenic specificity at the genus but not the species level.  相似文献   
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There was no difference in the establishment or rate of development of Oesophagostomum columbianum in young lambs after infective larvae were administered either orally or by injection directly into the rumen. However, the linear distributions in the intestine of encysted third-stage larvae differed according to the route of infection. The distributions of fourth-stage larvae, after migration to the large intestine, did not differ. It is suggested that the distribution of parasitic third-stage O. columbianum is host-dominated, depending on the site of exsheathment and the rate of passage of ingesta, but that of fourth-stage and adult worms involves active site selection by the parasite.  相似文献   
17.
1. Addition of sunflower oil (SFO) at 30 or 60 g/kg or three vegetable oils, namely SFO, soybean (SBO) or groundnut (GNO), at 30 g/kg to isocaloric and isonitrogenous broiler chicken diets were evaluated for possible counteractive effects against aflatoxin (AF) (0.3 microg B1/g diet) from 0 to 42 d of age. 2. Body weight, food intake and serum concentration of protein were lower in the AF group than in the control, whereas in the SFO and SBO supplemented groups they were comparable with those of the control. Sunflower oil at both concentrations exerted similar effects on growth. Groundnut oil did not improve growth or food intake in AF-fed birds. 3. The serum concentration of cholesterol and triglycerides decreased with AF feeding and was increased by supplementation of any of the three oils both in the control and in AF-fed groups. 4. Liver and giblet weight and liver fat content were increased by AF; these effects were countered by dietary oil inclusion, except for liver weight at 60 g/kg SFO. Weights of pancreas and gall bladder were increased by AF. Oil supplementation reduced the weight of pancreas in chickens given AF. 5. Humoral immune response was depressed by AF and dietary oil supplementation (particularly SFO or SBO) countered this effect. Other variables, namely, serum gamma glutamyl transferase activity, bone mineralisation, weights of lymphoid organs, kidney and adrenals, ready-to-cook yields and fat content in muscle and skin showed little or no effect of dietary oil supplementation. 6. It is concluded that dietary inclusion of SFO or SBO at 30 g/kg may alleviate the adverse effects of 0.3 microg/g of AF B1 in commercial broiler chickens. Groundnut oil, although showing beneficial effects on some biochemical variables, failed to improve growth performance.  相似文献   
18.
1. An experiment was conducted to determine optimal non-phytate phosphorus (NPP) concentrations for White Leghorn (WL) layers (22–72 weeks) fed diet containing 38 g Ca/kg.

2. Eight diets with graded concentrations (1.5–3.25 g/kg in increments of 0.25 g) of NPP were prepared. Each diet was fed to eight pen replicates containing 88 birds in each. Performance data was evaluated in three different phases (phase I-22–37 weeks, phase II-38–53 weeks and phase III-54–72 weeks). Optimum levels of NPP were determined by fitting a quadratic polynomial (QP) regression model.

3. Egg production (EP) was not affected (P = 0.059) by the concentration of NPP and interaction between NPP and diet phase was non-significant, indicating that the lowest concentration (1.5 g/kg diet) of NPP used in the study was adequate across the three phases. However, EP was influenced by phase (P < 0.001).

4. Optimum concentration of NPP for feed intake (FI) was estimated to be 1.5, 1.71 and 2.40 g/kg diet during phases I, II and III, respectively. FI per egg mass (EM) or feed efficiency (FE) responded quadratically with NPP and also differed significantly between phases. Optimum concentration of NPP for FE during phases I, II and III was 1.5, 2.56 and 2.32 g/kg diet, respectively.

5. Egg weight (EW), EM, shell weight and thickness were not affected by NPP concentration although all of these variables (except shell weight) were influenced by phases.

6. Breaking strength of tibia and Ca contents in tibia ash were not affected by the concentration of NPP, but bone ash and P contents in tibia ash were influenced (P < 0.001) by NPP. Predicted optimal concentrations of NPP for responses for tibia ash at 44 or 72 weeks, tibia ash P at 44 weeks and tibia ash P at 72 weeks were 1.55, 2.63 and 1.5 g/kg diet, respectively.

7. Based on the results, it was concluded that WL layers required 1.5 g, 2.63 g and 2.4 g, respectively/kg diet during phase I, II and III with the calculated daily intake of 137.3, 278.3 and 262 mg NPP/b/d.  相似文献   

19.

Relationship of scrotal bifurcation or splitness with breeding soundness traits was investigated in 15 Beetal bucks (17–20 months of age and 48.72?±?1.57 kg mean BW). Breeding soundness traits of conjoined/unsplit (n?=?6) scrotal bucks was compared with split (n?=?9) scrotal bucks having lengthwise >?1 in. bifurcation. Two consecutive semen ejaculations per buck were collected at monthly interval during summer season (April to June 2018) using intact buck as teaser and sexual behavior was simultaneously recorded. Scrotal morphometry parameters, i.e., scrotal circumference, scrotal volume, scrotal skin thickness, testis length, width, and thickness were also recorded. Bucks with split scrotum had relatively more scrotal dimensions (scrotal circumference (P?<?0.01), scrotal volume (P?<?0.01), testis length (P?<?0.01)) than conjoined scrotal bucks. Among various semen attributes, semen volume of first ejaculate (P?<?0.01), second ejaculate (P?<?0.05), mean semen volume (P?<?0.01), total sperm count of first ejaculate, and mean sperm count of both ejaculates were more (P?<?0.01) in split scrotal bucks. However, scrotal bifurcation had no influence on sexual behavior of bucks. It is concluded that Beetal bucks with split scrotum had relatively better breeding efficiency traits than conjoined scrotal bucks.

  相似文献   
20.
1. A total of 433 birds (7 weeks old) of both sexes belonging to Indian native breeds, including, Aseel, Kadakanath, Naked Neck and Frizzle fowl along with the imported breeds Dahlem Red, White Leghorn, Synthetic dam line broiler (SDL) and Naked Neck broiler were utilised to test the primary antibody response to sheep erythrocytes by haemagglutination test. The effect of genotype (breed), sex and their interactions on antibody response were also studied. 2. The results revealed the presence of natural antibodies in all groups under study. 3. All groups except broilers showed the highest HA titre on day 5 post immunisation, which gradually declined until the end of the experiment (19th day post immunisation). In broilers, the peak HA titre was observed on day 12. 4. Dahlem Red showed the highest response throughout. The lowest antibody response was recorded for broilers except on day 19 post immunisation when it exceeded the White Leghorn value. 5. Amongst the native Indian breeds, the Naked neck had the highest titre on day 5 post immunisation but the Aseel titre was highest on days 12 and 19. 6. Males tended to have higher titres than females in Aseel, Kadakanath, Naked Neck, White Leghorn and Naked Neck broilers whereas Frizzle, Dahlem Red and SDL broilers showed the converse. 7. Statistical analysis revealed significant variation in HA response among the various genetic groups on different days post immunisation. The apparent differences between sexes were not significant. However, interactions between breed and sex were significant on day 5 and 19 post immunisation.  相似文献   
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