Evaluation of ewe and lamb immune response when ewes were supplemented with vitamin E.
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Fifty-two Targhee twin-bearing ewes were used in a factorial arrangement of treatments to investigate the role of supplemental vitamin E (vit E); 0 (NE) vs 400 IU of vit E x ewe x (-1)d(-1) (E) and parainfluenza type 3 (PI3) vaccination; none (NP) vs PI3 vaccination (P) in immune function. Parainfluenza type 3 vaccination was used to evoke an immune response. Ewes receiving PI3 were vaccinated at 49 and 21 d before the expected lambing date. Ewes receiving vit E were orally dosed daily, 32 to 0 d before lambing. Blood was collected from ewes at the time of the initial PI3 vaccination and 4 h postpartum. Blood was collected from lambs (n = 104) at 3 d postpartum. Ewe and lamb sera were analyzed for anti-PI3 antibody titers, immunoglobulin G (IgG) titers, and vit E concentrations. Colostrum was collected 4 h postpartum and analyzed for IgG. The model for ewe and lamb analysis included the main effects of vit E and PI3, sex (lambs model only), and their interactions. No interactions were detected (P > 0.20) for any ewe or lamb variables. Serum anti-PI3 titers were greater (P < 0.01) in P ewes and their lambs than NP ewes and their lambs. Serum vit E concentrations were greater (P < 0.01) in E ewes and their lambs than NE ewes and their lambs. Colostral IgG titers and serum anti-PI3 titers did not differ (P > 0.20) between E and NE ewes. Serum IgG titers in E ewes and their lambs did not differ (P > 0.15) from IgG titers in NE ewes and their lambs. Lamb anti-PI3 titers did not differ (P = 0.76) between lambs reared by E and NE ewes. These results indicate that, although supplemental vit E to the ewe increased lamb serum vit E concentration, it had no effect on measures used in this study to assess humoral immunity in the ewe or passive immunity to the lamb. (+info)
Uterine eosinophils and reproductive performance in interleukin 5-deficient mice.
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Interleukin 5 is expressed in type 2 T lymphocytes and has a key role in driving the differentiation, recruitment and activation of eosinophils. Mice with a null mutation in the interleukin 5 gene (IL-5 -/- mice) have altered type 2 immune responses and severely depleted eosinophil populations. In the present study, the effect of interleukin 5 deficiency on the abundant population of eosinophils present in the female reproductive tract was investigated, and the reproductive performance in C57Bl/6 IL-5 -/- mice was measured. Endometrial eosinophils, detected on the basis of their endogenous peroxidase activity, were reduced in number by four-sevenfold during the oestrous cycle and in early pregnancy in IL-5 -/- mice. Eosinophils present in the cervix and decidual tissues at the time of parturition were similarly diminished. The temporal fluctuations in eosinophil recruitment and localization within these tissues were otherwise unchanged, indicating that interleukin 5 is not a necessary chemotactic agent in the female reproductive tract. Oestrous cycles were moderately greater in duration in IL-5 -/- mice (mean +/- SD = 5.6 +/- 1.0 days in IL-5 -/- mice versus 5.0 +/- 0.8 days in IL-5 +/+ mice), owing to an extended period in oestrus (2.7 +/- 0.9 days per cycle in IL-5 -/- mice versus 1.8 +/- 0.7 in IL-5 +/+ mice). The interval between placing females with males and the finding of copulatory plugs was reduced significantly in interleukin 5-deficient mice. Implantation rates and subsequent fetal development were comparable in IL-5 -/- and IL-5 +/+ mice, irrespective of whether pregnancies were sired by syngeneic (C57Bl/6) or allogeneic (CBA or Balb/c) males, apart from a 10% increase in placental size and a 6.5% decrease in placental∶fetal ratio seen on day 17 in pregnancies sired by CBA males. Parturition and post-partum uterine repair were not compromised in interleukin 5-deficient mice, as judged by the length of gestation, and the outcomes of pregnancies initiated at post-partum oestrus. The birth weights and growth trajectories of pups were significantly influenced by interleukin 5 status, with small but significant increases in the weights of IL-5 -/- pups, particularly C57Bl/6 and CBA F(1) animals, remaining evident until adulthood. These data are consistent with the view that eosinophils have a role in endometrial tissue remodelling associated with the oestrous cycle, but indicate that the events of pregnancy and parturition proceed quite normally in the absence of maternal and fetal interleukin 5. However, strain-dependent effects of interleukin 5 deficiency on placental growth and function and subsequent weight gain in the newborn indicate that this cytokine may act through the maternal or fetal immune axis to exert subtle influences on reproductive outcome. (+info)
Farrowing hut design and sow genotype (Camborough-15 vs 25% Meishan) effects on outdoor sow and litter productivity.
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Performance measures were evaluated for 125 outdoor sows and litters of two crossbred genotypes (Camborough-15 and 25% Meishan) and in two farrowing hut designs (American-style and English-style hut). Contemporary breeding groups of second-parity sows were evaluated in an intensive, outdoor research unit. Sow genotype and hut designs were arranged factorially. Seven complete blocks were evaluated over a 21-wk period. No interactions between environment and genotype were identified for sow and litter productivity. Litters farrowing in the English-style huts weaned 1.5 more (P < .05) piglets per sow (because of a lower preweaning mortality, P = .05) than did litters in the American-style huts. The 25% Meishan weaned 1.7 more (P < .01) pigs per sow than Camborough-15, because of a greater number of piglets born alive. The effects of hut style and genotype were additive and 25% Meishan sows in English-style huts weaned an average (+/- SEM) of 11.1 +/- .83 piglets per sow. The English-style arc hut design may improve outdoor pig production and increase competitiveness of the intensive, outdoor system. The 25% Meishan genotype has potential for increased pigs weaned per litter that must be considered in light of other features of this genotype such as body composition. (+info)
Effects of dietary valine concentration on lactational performance of sows nursing large litters. NCR-42 Committe on Swine Nutrition.
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A cooperative study, using 231 primiand multiparous crossbred sows from six experiment stations (IN, KS, MI, MN, ND, and OH), was conducted to determine the effects of elevating dietary valine concentration in corn-soybean meal diets on lactational performance of sows nursing large litters. Crossbred sows were fed diets containing a minimum of .60% lysine during gestation. Sows were allotted at farrowing to four dietary valine concentrations, .80, .95, 1.10, and 1.25%. Crystalline L-valine replaced cornstarch to maintain a constant ratio of corn:soybean meal across diets. Dietary lysine, provided by corn, soybean meal, and .15% crystalline L-lysine x HCl, was .90% in all diets. Sows were allowed ad libitum access to feed. Sows were weighed within 24 h after farrowing, and all litters were adjusted to > or = 10 pigs/litter by d 2 following farrowing. Average sow parity, number of pigs on d 2, and lactation length for the four treatments were, respectively, 2.3, 2.3, 2.3, 2.5; 10.9, 10.8, 10.8, 10.7; and 25.1, 24.5, 25.2, 25.0 d. The ADFI during lactation was 5.87, 5.77, 5.87, and 5.74 kg (P > .50); hence, valine intakes were 41, 48, 55, and 61 g/d (linear, P < .01). Lysine intake ranged from 51.5 to 52.7 g/d (P > .50). Sow weight after farrowing averaged 198 kg (P > .60). Overall pig survival to weaning was high (>92%), and the number of pigs weaned (10.1, 10.3, 10.3, 10.3) did not differ (P > .30) among treatments. Litter weaning weights (73.6, 73.6, 74.5, 72.6 kg), litter weight gains (55.1, 55.1, 56.0, 54.1 kg), sow weight change during lactation (-4.9, -5.4, -4.8, -6.3 kg), and return-to-estrus interval (7.5, 6.4, 6.9, 8.2 d) were not affected (P > .30) by dietary valine. There were no station x treatment interactions (P > .50). These results indicate no benefit of elevated dietary valine for lactating sows nursing > or = 10 pigs and consuming a corn-soybean meal diet containing .90% lysine and .80% valine. (+info)
Influence of time of infection during pregnancy with coxsackievirus B3 on maternal pathology and foetal growth in mice.
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Coxsackievirus B3 causes foetal wastage and growth retardation in mice which may be attributed to the action of the virus in destroying the maternal exocrine pancreas. Injection of virus on Day 4 or 8 of gestation caused greater foetal wastage than injection at 12 days. Foetal and placental weights in infected animals were less than in the controls but did not vary according to the time of infection. Little support is offered for the view that the mouse foetus differs in its susceptibility to Coxsackievirus B3 according to the stage in gestation of infection. (+info)
Specific physiological roles of cytosolic phospholipase A(2) as defined by gene knockouts.
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The cytosolic 85 kDa phospholipase A(2) (cPLA(2)) is a unique member of the phospholipase A(2) (PLA(2)) superfamily. Because PLA(2) activity and eicosanoid production are important in normal and pathophysiological states we and the laboratory of Shimizu created a mouse deficient in cPLA(2) (cPLA(2)(-/-) mouse). cPLA(2)(-/-) mice develop normally but the females have severe reproductive defects. cPLA(2)(-/-) mice suffer smaller infarcts and fewer neurological deficits after transient occlusion of the middle cerebral artery and have less injury after administration of a dopaminergic selective neurotoxin. cPLA(2)(-/-) mice have a more rapid recovery from allergen-induced bronchoconstriction and have no airway hyperresponsiveness. Peritoneal macrophages from cPLA(2)(-/-) mice fail to produce prostaglandins, leukotriene B(4) and cysteinyl leukotrienes after stimulation. Bone marrow-derived mast cells from cPLA(2)(-/-) mice fail to produce eicosanoids in either immediate or delayed phase responses. Thus the cPLA(2) knockout mouse has revealed important roles of cPLA(2) in normal fertility, generation of eicosanoids from inflammatory cells, brain injuries and allergic responses. Furthermore the cPLA(2)(-/-) mouse reveals that the many other forms of PLA(2) cannot replace many functions of cPLA(2). The importance of cPLA(2) in inflammation and tissue injury suggests that pharmacological targeting of this enzyme may have important therapeutic benefits. (+info)
Unilateral intrauterine horn insemination of fresh semen in cats.
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The sperm count required were investigated to obtain a conception rate of 80% by unilateral intrauterine insemination (UIUI) of fresh semen in cats. The conception rates obtained by insemination before and after ovulation were also examined. Thirty-six female cats aged 1-7 years were used in the experiments, and the number of experimental cases was 44. Seven male cats aged 2-12 years from which semen could be collected by the artificial vagina method were used. In artificial insemination, 100 iu x 2 or 250 iu of hCG was administered on days 2-4 of estrus, and sperm were introduced into the uterine horn with a greater number of ovulations (or mature follicles) 15, 20 and 30 hr after hCG administration by laparotomy. The inseminated sperm counts were 2 x 10(6) (Exp. 1). 4 x 10(6) (Exp. 2), and 8 x 10(6) (Exp. 3). As a result, ovulation was induced in 42 of 44 cases (induction rate: 95.5%) regardless of the dosage of hCG. Conception was obtained by UIUI in two of 16 animals (conception rate: 12.5%) in the Exp. 1, five of 16 animals (31.3%) in Exp. 2, and eight of 10 animals (80.0%) in Exp. 3. Regarding the relationship between the ovulation state at insemination and conception, the conception rate obtained by insemination before ovulation was clearly higher than that obtained by insemination after ovulation (p<0.05). Regarding the number of kits compared to the number of ovulations on the inseminated side, the percentages of cases in which the number of kits exceeded the number of ovulations on the inseminated side were similar in all groups inseminated with a different number of sperm. It is therefore necessary to investigate conception rates obtained by bilateral insemination to increase the fertility rate. Based on the above findings, it was shown that the sperm count required for fertilization by UIUI is 8 x 10(6). (+info)
Unilateral intrauterine horn insemination of frozen semen in cats.
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Frozen feline semen was prepared using two types of extenders, egg yolk Tris-fructose citric acid (EYT-FC) and egg yolk sodium citrate solution (EYC), and the semen qualities after thawing and the conception rates obtained by unilateral intrauterine horn insemination (UIUI) were investigated. Cats used in the experiment were six males and 11 females aged 2-12 years (the number of experimental cases was 17). For preparation of frozen semen, semen collected by the artificial vagina method was adjusted to I x 10(8) sperm/m/ and 7% glycerol, put in 250 microl straws, and then frozen using a cell freezer. The mean sperm motility after thawing was 30.0+/-9.7 (SE) % in the semen prepared with EYT-FC and 30.0+/-3.3% in the semen prepared with EYC. Four of seven animals were fertilized by UIUI using two straws in both extenders, and the conception rate was 57.1%. The mean ratios of number of kits to the number of ovulations in the inseminated side were 61.1+/-24.5% and 30.5+/-3.4% for EYT-FC and EYC, respectively, showing that the ratio tended to be higher in the semen prepared with EYT-FC. The above findings, comparing the two extenders for preparation of frozen feline semen, showed that EYT-FC is slightly superior to EYC. To increase conception and fertility rates, it may be important to increase the sperm count for insemination and to inseminate both uterine horns. (+info)