Ovarian follicle development and genital tract characteristics in different birthweight gilts at 150 days of age

In the last decades, selection for improved prolificacy has resulted in higher litter sizes and has thereby increased the proportion of low birthweight (LW) piglets. It is well documented that LW piglets have lower growth performance, muscle accretion and poor carcass quality. However, little is known about the relations of birthweight with subsequent reproductive performance in gilts. This study investigated the effects of birthweight on reproductive tract and ovarian follicle development in 150-day-old gilts. Twenty eight female pigs of different birthweight ranges (high-HW: 1.8-2.2 kg; low-LW: 0.8-1.2 kg) from higher parity commercial sows were reared until 150 days of age, and their body weights were recorded at weaning, end of nursery and end of the grower-finisher phase. The animals were killed and their reproductive tracts collected for biometrical and histomorphometrical analysis. LW gilts showed significantly lower body weights and growth rates during all phases of production compared to their HW counterparts (p < .01). Most biometrical measurements of the reproductive tract were similar between the experimental groups, except vaginal length and the gonadossomatic index (relative ovarian weight), which were affected by birthweight class (p < .05). LW females also showed fewer medium size (3-5 mm; p < .01) ovarian follicles, pre-antral follicles (p < .07) and more atretic follicles per ovarian cortex area (p < .05). Therefore, besides the effects on post-natal growth performance, birthweight affects vaginal length and the follicular dynamics process, which may impair the reproductive performance of replacement gilts.

Colostrum yield and litter performance in multiparous sows subjected to farrowing induction

The consumption of colostrum at a low level can compromise the survival and growth of piglets. Therefore, this study aimed to evaluate the effect of farrowing induction on colostrum yield, IgG concentration and the survival and performance of piglets until the weaning. Sows of parity 3 to 7 were assigned into two groups: Control (n = 48), sows with spontaneous farrowing; and induction (n = 48), sows induced to farrow on day 114 of gestation with a PGF₂ analogue. Colostrum and blood samples were collected from the sows, at farrowing and 24 hr later. Blood samples from the piglets were collected at 24 hr after birth. The performance of the piglets was evaluated in a subsample of 28 litters from each group. All piglets were weighed at 7, 14 and 20 days of age. The farrowing length, the number of piglets born alive, stillborn piglets, weight at birth, litter weight at birth and colostrum yield were not significantly affected (p > .05) by farrowing induction. There was no difference between the groups (p > .05) in the percentage of sows with obstetric interventions. Serum IgG concentration, in both sows and piglets, and colostrum IgG concentration were similar between the groups (p > .05). Furthermore, survival rate, piglet weight and litter weight at 7, 14 and 20 days of age were also similar between the groups (p > .05). Therefore, it can be concluded that the farrowing induction performed on day 114 of gestation does not affect the colostrum yield, the IgG concentration in colostrum and serum of piglets, and the litter performance until the weaning.

Intra-uterine growth retardation affects birthweight and postnatal development in pigs, impairing muscle accretion, duodenal mucosa morphology and carcass traits

The present study investigated the occurrence of intra-uterine growth retardation (IUGR) in newborn (n = 40) and 150-day-old (n = 240) pigs of different birthweight ranges (high, HW: 1.8–2.2 kg; low, LW: 0.8–1.2 kg) from higher-parity commercial sows and its impact on their subsequent development and carcass traits in a Brazilian commercial production system. HW newborn pigs had heavier organs than LW pigs (P < 0.01), and all brain : organ weight ratios were higher (P < 0.01) in LW compared with HW offspring, providing strong evidence of IUGR in the LW piglets. HW pigs had higher bodyweights and average daily gain (ADG) in all phases of production (P < 0.05), but ADG in the finisher phase was similar in both groups. Additionally, LW newborn and 150-day-old pigs showed a lower percentage of muscle fibres and a higher percentage of connective tissue in the semitendinosus muscle, greater fibre number per mm2 and a lower height of the duodenal mucosa (P < 0.05). On the other hand, HW pigs had higher hot carcass weight, meat content in the carcass and yield of ham, shoulder and belly (P < 0.01). Hence, lower-birthweight piglets may suffer from IUGR, which impairs their growth performance, muscle accretion, duodenal mucosa morphology and carcass traits.

Distribution of rotavirus genotypes after vaccine introduction in the Triângulo Mineiro region of Brazil: 4-Year follow-up study

BACKGROUND

Rotaviruses are the major cause of diarrhea in children for which a monovalent G1P[8] vaccine has been provided free for all Brazilian infants since March 2006.

OBJECTIVES

To investigate prevalence and genotypes of rotavirus strains causing diarrhea in children in Triângulo Mineiro, Minas Gerais, during 2007-2010, and to assess local vaccine impact.

STUDY DESIGN

Fecal specimens were analyzed for rotavirus detection and characterization by PAGE, RT-PCR and PCR-genotyping assays.

RESULTS

Overall, rotavirus was diagnosed in 12.1% (76/630) cases, accounting for 35.8% of the hospitalizations and 6.5% of outpatient attendance due to diarrhea. A trend in rotavirus disease reduction occurred in both cities (71.8% and 83.4% in Uberaba; 95.3% in Uberlândia) up to 2009, but it reversed in 2010 with increased rotavirus cases in Uberlândia. Short pattern G2P[4] strains were detected in all but three (96%) cases of mixed/P[NT] infections with long electropherotypes.

CONCLUSIONS

This 4-year follow-up study showed a reduction in rotavirus-related diarrhea and even skipped a rotavirus season, which is consistent with vaccine mediated protection. The 2007-2010 rotavirus epidemic curve reflected the natural cyclic fluctuation of the single G2P[4] genotype, with sharp reduction of cases in 2008 leading to lack of a rotavirus 2009 season (both cases and hospitalizations) followed by its come back in 2010. Diarrhea cases related to either vaccine serotype/genotype (G1 or P[8]) were not detected. Thus, a new scenario emerged with a single epidemic genotype replacing the cocirculation of great diversity of genotypes, thus far, a hallmark of the epidemiology of rotavirus in Brazil.

Administration of thyroxine affects the morphometric parameters and VEGF expression in the uterus and placenta and the uterine vascularization but does not affect reproductive parameters in gilts during early gestation

The aim of this study was to evaluate the effects of thyroxine administration on morphometric parameters, expression of vascular endothelial growth factor (VEGF) and vascularization in the uterus and placenta and reproductive parameters in gilts at 70 days of gestation. At 150 days of age, i.e., before first heat, 20 gilts were randomly divided into two experimental groups: treated (n=10) and control (n=10). The treated group received a daily dose of 400 μg of L-thyroxine (T(4)) in their diet until slaughter and the control group received only typical meals. Before artificial insemination, blood was collected to determine plasma total T(4). The gilts were inseminated in the second oestrus and slaughtered at 70 days of gestation. The foetal thyroid follicular epithelium height, number, size and weight of foetuses; foetal myogenesis, corpora lutea number, embryonic mortality rate, uterine weight, placental weight and placental fluid volume were measured. Histomorphometric and immunohistochemical analysis of uterus and placenta were determined. The averages of all variables were compared by the Student's t-test. The gilts treated with thyroxine showed significant increase of plasma total T(4). At 70 days of gestation, the heights of the trophoblastic epithelium, endometrial epithelium and endometrial gland epithelium were significantly higher in the group treated with T(4). The expression of cytoplasmatic and nuclear VEGF in trophoblastic cells and the number of blood vessels per field in endometrial stroma were significantly higher in the gilts treated with T(4). No other significant differences between groups were obtained with respect to other parameters (p>0.05). We conclude that oral administration of T(4) up to 70 days of pregnancy in gilts affects the morphometric parameters, the expression of placental VEGF and the uterine vascularization but does not affect reproductive parameters in gilts during early gestation.

Multicenter trial of dynamic cardiomyoplasty for chronic heart failure. The American Cardiomyoplasty Group

OBJECTIVES

The purpose of this study was to prospectively assess the effect of dynamic cardiomyoplasty in patients with symptomatic chronic heart failure.

BACKGROUND

Since the first procedure was performed in 1985, dynamic cardiomyoplasty has been developed for use in patients with chronic heart failure. The aging population in developed countries has made heart failure a growing public health concern. Heart transplantation is appropriate or available for only a small proportion of these patients because of limited donor supply. Effective alternatives to transplantation are needed.

METHODS

Eight centers in North and South America performed 68 cardiomyoplasty procedures between May 1991 and September 1993. Data were prospectively collected every 6 months and compared with preoperative values using paired t tests, chi-square tests and actuarial survival analyses.

RESULTS

Patients had a mean (+/- SD) age of 57 +/- 1 years and were predominantly male (53 [78%] of 68). Heart failure etiology was classified as idiopathic in 47 (69%) of 68 patients and ischemic in 21 (31%). The in-hospital mortality rate was 12% (8 of 68), and the survival rate at 6 and 12 months was 75 +/- 5% and 68 +/- 6%, respectively. Objective improvements were seen at 6 months (n = 49) in left ventricular ejection fraction (23 +/- 1% vs. 25 +/- 1%, p = 0.05), stroke volume (50 +/- 2 vs. 56 +/- 3 ml/beat, p = 0.02) and left ventricular stroke work index (26 +/- 1 vs 30 +/- 2 g/m2 per beat, p = 0.01). Improvements in mean New York Heart Association functional class (3 +/- 0.04 vs. 1.8 +/- 0.1, p = 0.0001) and activity of daily living score (59 +/- 3 vs. 80 +/- 2, p = 0.0001) were also observed. There were no significant changes at 6 months in peak oxygen consumption (15 +/- 1 vs. 16 +/- 1 ml/kg per min), cardiac index (2.26 +/- 0.08 vs. 2.33 +/- 0.08 liters/min per m2), pulmonary capillary wedge pressure (19 +/- 2 vs. 18 +/- 1 mm Hg) or heart rate (87 +/- 2 vs. 82 +/- 3 beats/min).

CONCLUSIONS

These data suggest that dynamic cardiomyoplasty improves ventricular systolic function, reduces symptoms of heart failure and improves objective measures of quality of life in patients with congestive heart failure. This improvement occurred without changes in peak exercise capacity, ventricular filling pressure or actuarial survival.