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111.
Martín-Palomino P Píriz S Jiménez R Serrano FJ Vadillo S 《Acta veterinaria Hungarica》2004,52(3):275-285
This research consists of an evaluation of the effectiveness of different substances administered as adjuvants in the stimulation of humoral immune response induced by the vaccine composed of strains A1, A2 and C of Dichelobacter nodosus. To do this, a total of 120 Merino sheep were vaccinated and revaccinated. These sheep were selected from a farm located in the region of Extremadura (Spain), and they were divided into 12 groups of 10 animals each. An additional group with 10 sheep was used as control. The immune response (titre of antibodies) was determined by agglutination tests and ELISA. The most pronounced immune response was obtained by the use of Freund's incomplete adjuvant and aluminium hydroxide as adjuvants. 相似文献
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Two trials were conducted to determine the effects of weaning age on pig performance in a multisite production system. The second trial also evaluated the effects of modifying the nursery feeding program according to weaning age. In Trial 1 (2,272 pigs), treatments included weaning litters at 12, 15, 18, or 21 d of age. In Trial 2 (3,456 pigs), litters were weaned at 15, 16, 18, 19, 21, or 22 d of age and categorized into three treatments (15.5, 18.5, or 21.5 d of age). In Trial 2, pigs in each age group were fed one of two nursery feeding programs. Nursery feeding programs varied in both diet formulation and in the quantity of diets fed containing increased levels of whey and spray-dried animal plasma. Each trial was conducted as a randomized complete block design with four blocks of nursery and finishing sites. All weaning-age treatments were weaned from a 7,300-sow farm on the same day into the same nursery. Each block remained intact as pigs moved from nursery to finishing site. Increasing weaning age (12, 15, 18, or 21 d in Trials 1; and 15.5, 18.5, or 21.5 d in Trial 2) increased (linear, P < 0.001) ADG (299, 368, 409, 474 +/- 7 g/d; 435, 482, 525 +/- 13 g/d) and tended to decrease (linear, P < 0.09) mortality (5.25, 2.82, 2.11, 0.54 +/- 0.76%; 2.17, 1.56, 1.30 +/- 0.36%) in the initial 42 d after weaning. Finishing ADG (722, 728, 736, 768 +/- 11 g/d; 783, 790, 805 +/- 11 g/d) also improved (linear, P < 0.01) with increasing weaning age. Overall, increasing weaning age increased (linear, P < 0.001) wean-to-finish ADG (580, 616, 637, 687 +/- 8 g/d; 676, 697, 722 +/- 6 g/d), weight sold per pig weaned (94.1, 100.5, 104.4, 113.1 +/- 1.3 kg; 107.6, 111.6, 116.2 +/- 1.1 kg), and decreased (linear, P < 0.03) mortality rate (9.4, 7.9, 6.8, 3.6 +/- 0.95%; 3.9, 3.4, 2.5 +/- 0.5%). Altering the nursery feeding program did not affect wean-to-finish growth performance. In this multisite production system, increasing weaning age from 12 to 21.5 d of age increased weight sold per pig weaned by 1.80 +/- 0.12 kg for each day increase in weaning age. These studies suggest increasing weaning age up to 21.5 d can be an effective management strategy to improve wean-to-finish growth performance in multisite pig production. 相似文献
114.
Comparison of three methods of feeding sows in gestation and the subsequent effects on lactation performance 总被引:1,自引:0,他引:1
Young MG Tokach MD Aherne FX Main RG Dritz SS Goodband RD Nelssen JL 《Journal of animal science》2004,82(10):3058-3070
A total of 684 sows from breeding groups over 6 wk was used to compare three methods of feeding during gestation on gestation and lactation performance. Control gilts and sows were fed according to body condition based on a scale of 1 to 5 (1 = thin, 5 = fat). Sows were visually assessed for body condition at breeding and were assigned a daily feed allowance to achieve a BCS of 3 at farrowing. Treatment 2 used feeding levels based on backfat thickness (measured between d 0 and 5 after breeding) and weight at weaning for sows or service for gilts. Feed allowance was calculated to achieve a target backfat of 19 mm at farrowing, and remained constant from d 0 to 101 of gestation. Feed allowances were based on modeled calculations of energy and nutrient requirements to achieve target sow maternal weight and backfat gains. Treatment 3 was identical to Treatment 2, except that feeding pattern was altered for thin sows and gilts (<15 mm at service) in an attempt to reach 19 mm by d 36 of gestation. Sows were weighed at the previous weaning, and gilts were weighed at service, with both weighed again between d 112 and 114 of gestation. Backfat was measured between d 0 and 5, and again between d 108 and 113 of gestation. At farrowing, sows on Treatments 2 and 3 had 19 and 19.1 mm of backfat, respectively, whereas control sows tended to have greater (P < 0.07) backfat (20 mm). On average, sows targeted to gain 6 to 9 mm of backfat failed to reach target gains regardless of feeding method. Feeding sows in gestation based on backfat (Treatments 2 and 3) resulted in a numerically higher proportion of sows in the target backfat range of 17 to 21 mm (40.2, 53.3, and 52.6% for control and Treatments 2 and 3, respectively) at farrowing and a numerically lower percentage of fat sows (>21 mm), but no difference in the percentage of thin sows (<17 mm) compared with feeding based on body condition. In conjunction with this observation, sows fed based on BCS were fed higher (P < 0.05) feeding levels in gestation than were sows fed based on backfat depth. Gestation feeding method had no effect on performance during lactation. Feed intake in lactation was lower (P < 0.05) for high backfat sows (>21 mm) at farrowing compared with sows with <21 mm. The high proportion of sows in the optimal backfat category demonstrates that feeding based on backfat and BW has potential for facilitating more precise feeding during gestation. 相似文献
115.
Kling J 《Science (New York, N.Y.)》2006,311(5765):1305-1306
116.
Ortega-Pacheco A Rodriguez-Buenfil JC Segura-Correa JC Montes de Oca-González AR Jiménez-Coello M 《The Journal of small animal practice》2006,47(5):266-269
OBJECTIVES: To determine the prevalence of fetal resorption in 77 pregnant bitches and its association with the age, size and body condition score of the bitch and to determine the frequency of transuterine migration of embryos. METHODS: The number and position of embryos or fetuses and placental zones were registered postmortem. The prevalence of fetal losses was determined by comparing the number of corpora lutea with the number of embryos or fetuses in each bitch. The prevalence of transuterine migration of embryos was determined by correlating the number of fetuses in each horn and the number of corpora lutea in the ipsilateral ovary. RESULTS: Fetal resorption zones were demonstrated in 42.9 per cent of the bitches. However, pregnancy continued in 84.9 per cent of cases. Of the fetal losses, 25.9 per cent were determined by counting the number of corpora lutea and viable embryos or fetuses. Young bitches tended to have a higher probability of fetal resorption than adult bitches (P<0.06). The presence of fetal resorption zones was not associated with size or body condition. Transuterine migration of embryos had occurred in 15.8 per cent of the bitches. CLINICAL SIGNIFICANCE: This study demonstrated that embryo resorption is a normal event in the bitches, with a higher prevalence than previously thought. 相似文献
117.
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119.
Shelton NW Tokach MD Dritz SS Goodband RD Nelssen JL DeRouchey JM Usry JL 《Journal of animal science》2012,90(1):361-372
Four experiments were conducted to examine the effect of porcine circovirus type 2 (PCV2) vaccination on the response of growing and finishing pigs (PIC 337 × 1050) to increasing dietary Lys. Experiments 1 and 2 evaluated 38- to 65-kg gilts and barrows, respectively, and Exp. 3 and 4 evaluated 100- to 120-kg gilts and barrows, respectively. Gilts and barrows were housed separately in different barns. Treatments were allotted in a completely randomized design into 2 × 4 factorials with 2 PCV2 treatments (PCV2-vaccinated and nonvaccinated) and 4 standardized ileal digestible (SID) Lys:ME ratios (2.24, 2.61, 2.99, and 3.36 g/Mcal in Exp. 1 and 2 and 1.49, 1.86, 2.23, and 2.61 g/Mcal in Exp. 3 and 4) within each experiment. There were 5 pens per treatment. At the start of Exp. 1 and 2, there were more pigs per pen (P < 0.001) in vaccinated pens because vaccinated pigs had a greater survival rate than nonvaccinated pigs, and this increase was maintained throughout the experiments. Removal rate approached 30% in nonvaccinated barrows and more than 20% in nonvaccinated gilts. Observation suggested that the removals were largely due to PCV2-associated disease. No PCV2 vaccination × SID Lys:ME ratio interactions (P > 0.10) were observed in any of the 4 studies. In Exp. 1 and 2, PCV2-vaccinated pigs had increased (P < 0.001) ADG compared with nonvaccinated pigs. The growth response was primarily due to increases in ADFI, which suggests that vaccinated pigs have a greater Lys requirement (g/d) than nonvaccinated pigs. In Exp. 1, increasing the SID Lys:ME ratio increased (quadratic; P < 0.04) ADG and G:F, with pigs fed the 2.99 g/Mcal ratio having the greatest ADG and G:F. In Exp. 2, increasing the SID Lys:ME ratio improved (linear; P < 0.001) G:F. In Exp. 3, ADG and G:F increased (P < 0.05) in a quadratic manner as the SID Lys:ME ratio fed increased. In Exp. 4, increasing the SID Lys:ME ratio increased ADG (linear; P < 0.001) and G:F (quadratic; P = 0.03). Although PCV2 vaccination improved growth, the corresponding increase in ADFI did not increase the optimal SID Lys:ME ratio for growing and finishing barrows and gilts. 相似文献
120.
Jiménez-Coello M Acosta-Viana KY Guzman-Marin E Ortega-Pacheco A 《Zoonoses and public health》2012,59(Z2):166-169
American Trypanosomiasis (AT) is an infectious parasitic disease produced by the protozoa Trypanosoma cruzi (T. cruzi). Infection is acquired by vectorial via but can also be transmitted congenitally, by ingestion of an infected host, by transfusion with contaminated blood or transplant of organs from an infected donor. Currently, AT is widely distributed from the South of the United States to South America. In Mexico, the presence of the parasite has been reported throughout the country where several reservoirs such as dogs, opossums, rats and cats have been identified. Yucatan is in the south-east of Mexico where AT is endemic and has been reported since 1940s. There is little information about the role of pigs as reservoirs of T. cruzi. The frequency of specific antibodies against T. cruzi was determined in fattening pigs from Yucatan, Mexico. After sampling in the 3 main areas of pig production in the state, IgG ELISA and Western blot were performed to identify seropositive cases. Association of farm size, farm area and production system with infected pigs was evaluated. From 273 sampled pigs, 5.4% (n = 15) positive cases were found. No association with evaluated factors and infected pigs was found. Pigs are also reservoirs of T. cruzi in the studied area. These findings are considered important to improve vectorial control in the area in order to avoid the parasite infection in animal populations destined for human consumption and avoid further transmission to humans. 相似文献