Prenatal and postnatal influences on growth and fat measurements in swine

Data from 153 foster groups, each consisting of a dam and a nurse, were analyzed separately for breed (Lacombe, Yorkshire) parity (first, second), and sex of piglet (boar, gilt) to estimate prenatal, postnatal and prenatal X postnatal influences on growth and fat measurements. Significant differences were not observed between breeds, parity and sex of piglets; the estimates were pooled over these traits. Prenatal effects were the major contributing factor in the determination of preweaning growth rate, weaning weight, postweaning average daily gain and allometric growth coefficient, rib and loin fat deposition coefficients. Postnatal influence was of minor importance and the prenatal X postnatal interaction was of negligible consequence. These observations indicated that crossfostering of piglets between parities and breeds without regard for the sex of the piglet would not seriously bias subsequent performance testing results. Heritability estimates for weaning weight, postweaning growth rate and backfat thickness differed from published values.     

GDF9 affects the development and tight junction functions of immature bovine Sertoli cells

Transforming growth factor‐β (TGFβ) superfamily are critical regulators of germ cell development that act as extracellular ligands of the signal transduction pathways regulating proliferation, apoptosis and other aspects of cell behaviour. As a member of the TGF‐β superfamily, growth differentiation factor 9 (GDF9) plays a critical role in ovarian follicular development and the ovulation rate in females; however, its role in the testis has not been well elucidated. The aim of this study was to investigate the expression of GDF9 and its receptor genes BMPRII and ALK5 in prepuberal bovine Sertoli cells (SCs). In addition, we assessed the effects of GDF9 on immature SCs apoptosis, the cell cycle and tight junction functions. We found that GDF9 and its receptor genes BMPRII and ALK5 were expressed in immature SCs. Exogenous GDF9 significantly promoted SCs proliferation and inhibited the apoptosis of SCs by significantly upregulating Cyclin E (cell cycle) and bcl‐2 (anti‐apoptosis) mRNA expression and downregulating caspase‐3 (pro‐apoptosis) mRNA expression. Meanwhile, exogenous GDF9 significantly decreased the value of transepithelial electrical resistance by significantly downregulating claudin‐11 mRNA expression and influencing the distribution of occludin. In conclusion, this study reveals that GDF9 is a key regulator of bovine SCs through the modulation of the cell cycle, apoptosis and tight junction functions.     

Influence of age and testosterone levels on masculine development in rams

Fifty wethers and 51 spring-born rams were divided into five groups and slaughtered at different seasons of the year at average ages of 271, 361, 459, 557 or 652 d to determine the age and season at which differences in secondary sex characteristics could be detected. Serum testosterone concentrations and testes weights were low in January when the rams were 271 d of age and again in April at 361 d of age. By July, at 459 d of age, testosterone concentrations and testes weights had peaked and then decreased the following November at 557 d and February at 652 d. In contrast with plasma testosterone concentrations and testes weights, buckiness scores, splenius to semimembranosus or semitendinosus muscle ratios, splenius muscle weights and neck and shoulder percentages were not seasonal. All of these measures increased significantly up to July and continued to increase slowly, but not significantly, thereafter. Muscle color and texture scores and rib eye color scores tended to increase in a linear manner for both rams and wethers as age increased. Subcutaneous fat from rams was yellower and softer than that from wethers over all age groups. Ram fat firmness did not change (P greater than .05) with age, and the only significant change in ram fat color was between the groups at 271 and 361 d of age. Overall, season of year coupled with higher levels of serum testosterone was related to initial development of secondary sex characteristics in ram lambs.     

Profiling of miRNAs in porcine Sertoli cells

Background: Sertoli cells(SCs) create a specialized environment to support and dictate spermatogenesis.MicroRNAs(miRNAs), a kind of ~ 22 nt small noncoding RNAs, have been reported to be highly abundant in mouse SCs and play critical roles in spermatogenesis. However, the miRNAs of porcine SCs remain largely unknown.Methods: We isolated porcine SCs and conducted small RNA sequencing. By comparing miRNAs in germ cells, we systematically analyzed the miRNA expression pattern of porcine SCs. We screened the highly enriched SC miRNAs and predicted their functions by Gene Ontology analysis. The dual luciferase assay was used to elucidate the regulation of tumor necrosis factor receptor(TNFR)-associated factor 3(TRAF3) by ssc-miR-149.Results: The analysis showed that 18 miRNAs were highly expressed in SCs and 15 miRNAs were highly expressed in germ cells. These miRNAs were predicted to mediate SC and germ cell functions. In addition, ssc-miR-149 played critical roles in SCs by targeting TRAF3.Conclusion: Our findings provide novel insights into the miRNA expression pattern and their regulatory roles of porcine SCs.     

Immunoglobulins and immunoglobulin-containing cells in the reproductive tract of normal rams

The levels of the immunoglobulins IgA, IgG1, IgG2, and IgM were measured in serum and fluid from various locations in the reproductive tract of normal rams. These fluids included semen, preputial washings, and fluid from the accessory sex glands (ASG), vasa deferens, rete testes, and tissue fluid from the seminal vesicles, bulbourethral glands, epididymal tails and efferent ducts. In addition, the prevalence of specific Ig-containing cells (ICC) was measured in sections of formalin fixed tissues stained by an indirect peroxidase-antiperoxidase labelling technique. Mean IgA levels in semen (1.23 mg/ml) and ASG fluid (0.46 mg/ml), were higher than in serum (0.19 mg/ml) and were at levels higher than IgG1 or IgG2 levels in semen, ASG fluid, and preputial washings, thus confirming the existence of a local immune system primarily in the ASG of ram genitalia. Relatively low concentrations of IgA and IgG in other genital fluids and IgG levels in these fluids were consistent with diffusion from serum. The relatively high prevalence of IgA-containing cells in bulbourethral (56% of all ICC) and prostate (49%) glands confirmed these tissues as major sites of local Ig production. ICC were also found in large numbers beneath pelvic urethral and preputial epithelia, but these were predominantly IgG-containing (88 and 72% respectively).     

产前应激与胎儿发育

产前应激(prenatal stress,PS)是妊娠期母体受到各种内外界环境因素、社会和心理因素刺激时,所表现出的全身性、特异性适应反应。产前应激不仅影响母体本身,还可能影响胎儿的正常发育,甚至诱发终身疾病。发育中的胎儿对外界刺激具有较高的敏感性和较低的适应性,且产前应激对胎儿的生理和心理上都有较大的危害,致使后代生长发育迟缓、免疫功能紊乱、疾病易感性增加,而产前应激对胎儿的影响取决于应激的类型、时间、强度以及后代的性别,因此本研究主要综述光照应激、束缚应激、冷应激等几种产前应激对胎儿发育的影响,为研究动物产前应激提供理论基础。     

Urinary tract ultrasonography in normal rams and in rams with obstructive urolithiasis

We determined the position, dimensions, and structure of the kidneys, ureters, bladder, and urethra in 20 healthy, adult rams by use of ultrasonography. The findings were compared with those of seven rams with obstructive urolithiasis, thus establishing criteria for the diagnosis of urolithiasis via ultrasonography. A 5.0 MHz convex transducer was placed over the right paralumbar fossa to examine the kidneys, and a 5.0 MHz linear rectal transducer was used to examine the bladder and urethra transrectally. All examinations were performed on standing rams. The left kidney had a length of 8.4 ± 0.3 cm (mean ± SD), a width of 4.7 ± 0.3 cm, and a depth of 4.4 ± 0.3 cm. The diameter of the renal sinus of the left kidney was 1.5 ± 0.2 cm. The circumference of the medullary pyramids measured 2.8 ± 0.3 cm. Similar ultrasonographic measurements were obtained for the right kidney. The mean diameter of the bladder of 12 rams was 7.5 ± 2.8 cm. The diameter of the bladder could not be determined in the remaining eight rams because it was greater than 10 cm and therefore beyond the penetration depth of the scanner. The only part of the urethra which could be visualized ultrasonographically was the internal urethral orifice. It had a diameter of 0.2 ± 0.1 cm.

Ultrasonographic examination of seven rams with obstructive urolithiasis revealed a markedly dilated urethra and urinary bladder. Due to severe cystitis, the contents of the urinary bladder appeared as multiple, tiny, uniformly distributed echoes. The renal pelvis and medullary pyramids of both kidneys were dilated in four rams. In two rams, uroperitoneum and accumulation of urine in the abdomen were diagnosed via ultrasonography. In one ram this was due to a ruptured ureter and in one to a ruptured bladder. The results of this study indicate that ultrasonography is a useful aid in the diagnosis of obstructive urolithiasis.

     

Hypospadias in rams

In an abattoir survey conducted in south-west England, 15 of 6521 rams aged three to 12 months had hypospadias; in 27 others the scrotum was completely or partly divided, but they had no other abnormalities of the urinary or genital systems. The lesions observed in 11 of the rams in the abattoir survey, and in four young rams and one mature ram found during visits to farms, are described in detail. Five of them had periscrotal openings of the urethra and in the other 11 the openings were in a perineal position, close to the anus. In all of them the penis was underdeveloped, the prepuce had failed to fuse and the galea faced in a caudal direction. They all had completely or partially divided scrotums, and signs of urine scalding of the scrotum were visible.     

Epididymitis in rams and lambs

This article reviews lamb epididymitis and epididymitis caused by Brucella ovis. Pathogenesis, occurrence, signs and lesions, diagnosis, prevention, and treatment are discussed.     

Prenatal development of the bovine lung

A light and electronmicroscopic study of the development of the bovine lung was conducted, using tissues from 60 abatoir collected fetuses of various ages. Standard categorical stages of development were used to classify development stages relative to fetal age. The sequencial development of the bovine lung is described and compared with that of other species in which similar studies have been made.     

Prenatal development of the bovine oviduct

In this study the development of the bovine Fallopian tube was investigated using light microscopic methods. Formation and differentiation of the Müllerian duct were studied in mesonephroi of 16 embryos and fetuses with a crown-rump lengths (CRL) of 0.9-8.4 cm. The funnel field, the rostral beginning of the Müllerian duct was first observed at a CRL of 0.9 cm. It appears as a thickening of the mesothelium on the craniolateral side of the mesonephros. During later development the Müllerian duct emerges by caudal outgrowth from the funnel field. Formation of a common basal lamina surrounding the caudal tips of Müllerian and Wolffian ducts could be observed at all stages up to CRL of 2.7 cm. The mesothelium and the epithelium of the Wolffian duct adjacent to the Müllerian duct showed a modification of epithelium height in all examined stages. Probably the Wolffian duct influences the growth of Müllerian duct by epithelio-mesenchymal interactions. Fetuses from a CRL of 12.0 to 94.0 cm were used for investigation of the prenatal differentiation of the oviductal mucosa. Folding of the oviductal mucosa started at a CRL of 29.0 cm and continued until birth. Individual primary, secondary and tertiary folds are formed in special proliferation zones and epithelium-folding buds. The cellular differentiation of the oviductal epithelium involves the formation of ciliated and secretory cells during different times of prenatal development. Ciliogenesis was first detected at a CRL of 33.0 cm. Active secretory cells could be observed in the oviductal epithelium from a CRL of 64.0 cm onwards.     

Impaired postnatal development in C/EBPbeta-deficient mice

Tail DNA genotyping of fetal and neonatal mice from C/EBPbeta heterozygous parents was performed to determine whether the decreased number of surviving C/EBPbeta mutants was caused by prenatal or postnatal death. Eighty-four 3-week-old mice born of heterozygous parents had significantly lower numbers of C/EBPbeta-deficient offspring than the expected Mendelian ratio (29.8%+/+, 65.5%+/-, 4.76%-/-, P<0.05). The genotypes of 72 fetal mice from intercrossed heterozygotes showed approximately the expected 1:2:1 Mendelian ratio (18.1% +/+, 52.8% +/-, 29.2% -/-, P>0.05). No difference in the proportions by sex could be detected in these perinates. This data indicates that C/EBPbeta-deficient mice have unknown lethal problems between the embryonic stage and weaning.     

Renal excretion of drugs during postnatal development in piglets

The renal excretion of organic acids involves three mechanisms: glomerular filtration, active tubular secretion and passive tubular reabsorption. The postnatal development of each of these mechanisms was assessed in piglets. From birth to 8 weeks of life glomerular filtration rate (GFR) and clearance of p-amino-hippurate (PAH) rose twofold while the maximal tubular secretion of PAH (Tm_PAH) rose fourfold. Thus, the active secretion increased in parallel with GFR when the transport mechanism was unsaturated, whereas it increased about twofold more than GFR at saturation point. Age differences in the passive reabsorption were evaluated by using sulphachlorpyridazine (SCP) as test substance. Although the renal handling of SCP includes both secretion and reabsorption, the age-dependent rise in the ratio between clearance of ultrafiltrable SCP and GFR indicated a relative decrease in reabsorption with age.     

Early postnatal development of central corneal thickness in dogs

Objective To investigate the changes in corneal thickness that occur during maturation of the canine eye over the first months of life. Animals studied Dogs of two different breeds with ages ranging from 14 days to 42 weeks of age. Procedures The central corneal thickness was measured by ultrasonic pachymetry every week for the first month after eyelid opening (around 14 days) and then every month until 42 weeks of age. Segmented regression was applied to capture the two phases observed in the central corneal thickness plotted against age. Breed, eye and gender were also included in the model. Results Mean central corneal thickness (CCT) values initially decreased following eyelid opening, with the lowest point being reached at around 6 weeks of age. Then CCT gradually increased as the dogs matured. Differences between left and right eye were not significant. Breed and gender effects were significant factors in the statistical model. Conclusions Following eyelid opening there is an initial decrease in corneal thickness until approximately 6 weeks of age, which presumably mirrors maturation of corneal endothelial cell function. After 6 weeks of age the CCT increases with age until approximately 30 weeks of age after which there was only a gradual increase over the remainder of the study period. A similar pattern of changes in corneal thickness in humans has been previously recorded.     

Chemotherapy of brucellosis in rams

Abstract

Extract

Recognition that one infective agent could cause ram epididymitis and ewe abortion in New Zealand was due to McFarlane et al. (1952 McFarlane, D., Jebson, J. L., Hartley, W. J., Salisbury, R. M., McClure, T. J. and Osborne, H. G. 1952. Aust. vet. J., 28: 226–226. [Crossref] , [Google Scholar]). The organism was not identified at that time, but Buddie and Boyes (1953 Buddle, M. B. and Boyes, B. W. 1953. Aust. vet. J., 29: 145–153. [Crossref] , [Google Scholar]) classified it in the genus Brucella—possibly a variant of Br. melitensis. This finding provided a basis for research on control and treatment of the disease. The present paper describes studies on one aspect of this problem, the chemotherapy of affected rams.