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Biomedical subjects

J A Renden

Publications and source records attributed to J A Renden.

34 records · Page 2Linked to original sources
PubMed1986

Sperm release from the uterovaginal storage gland of the chicken: A perfusion study.

In vitro and in vivo intraluminal perfusions of the uterovaginal junction of the oviduct were performed in an attempt to quantitate sperm release from the uterovaginal sperm host glands (UV-SHG) of breeder hens. Spermatozoa were present in the perfusate at all time periods examined. However, the quantity of spermatozoa recovered showed a significant (P<0.0001) decline over a 2-h perfusion period in all experiments. Furthermore, histological examination of the perfused oviduct revealed significantly lower percentages (P<0.05) of UV-SHG containing spermatozoa compared to unperfused control oviducts. The perfusion techniques used in this study seemed to influence the pattern of sperm release from the storage glands.

Journal Article↗
PubMed1986

The effect of feeding programs on reproductive traits and selected blood chemistries of caged broiler breeder males.

The effects of five different feeding levels [136, 125, 113, 102, and 91 g/male/day of a 13.1% crude protein (CP), 3167 kcal metabolizable energy (ME)/kg feed] were evaluated on the reproductive traits of caged adult broiler breeder males from 30 to 60 weeks of age. Individual body weights, semen volume, sperm cells per ejaculate, and fertilizing ability were measured at 30, 40, 50, and 60 weeks of age. To assist in measuring the effect of feed restriction on metabolism during these periods, average hematocrits, plasma cholesterol, total protein, and uric acid levels were analyzed. Significant (P less than .05) reductions were observed in average body weights, semen volume, sperm cell numbers per ejaculate, testicular weights, and hematocrits with feed restriction at the 91-g compared to the 136-g feeding level. At 40 weeks of age, the percent of males producing semen was significantly reduced for the 102-and 91-g compared to the 136-g feeding level. Average plasma cholesterol levels were significantly increased at the 91-g compared to the 136-g feeding level, but little effect was observed in plasma total protein and uric acid levels. Correlation coefficients were negative for plasma cholesterol to body weights, sperm numbers per ejaculate, and testicular weights but positive for body weights to hematocrits and testicular weights.

Animals↗
PubMed1986

Body composition and other physical parameters as determinants of age at sexual maturity and performance efficiency in dwarf hens divergently selected for body weight.

Hens in this study were produced from random breeding within lines (high, low, and control) of dwarf White Leghorns that had been divergently selected for four generations for 20-week body weight. Birds were weighed at 10 weeks of age and placed in individual cages at 18 weeks of age. Body weights, shank lengths, and egg weights were obtained at sexual maturity (day of first egg) and at 4, 8, 12, and 16 weeks after sexual maturity. Egg production was recorded during 28-day periods. Thirty hens/line were sampled at sexual maturity and at the above times after sexual maturity for body composition (percent fat, protein, moisture, and ash). High line hens showed increased percent body fat and reduced percent protein and moisture compared to low and control hens. Coefficients of determination (R2) for age at sexual maturity and body weight were small (R2 less than or equal to .20) for high and control hens. There were no meaningful relationships between body weight or other physical measurements and sexual maturity in low hens. There were no significant relationships between body composition and age at sexual maturity in high and control hens. There was a strong cubic association (R2 = .73; P less than .001) between percent ash and age at sexual maturity in low hens, although the biological importance of this relationship was uncertain. Coefficients of determination between body weight and performance efficiency (egg mass per body weight) were small to moderate (R2 = .04 to .46) for high and control hens.(ABSTRACT TRUNCATED AT 250 WORDS)

Aging↗
PubMed1985

Fluorometry of poultry semen: its application in the determination of viability, enzyme leakage, and fertility.

The accuracy of fluorometry for estimating percentages of dead chicken spermatozoa was investigated by comparing this technique with the eosin-nigrosin differential staining procedure and with glutamic oxaloacetic transaminase (GOT) concentration in seminal plasma. The relationship between percent dead sperm measured by fluorometry and fertility was also examined. The correlation coefficient of percentage of dead spermatozoa determined by fluorometry with eosin-nigrosin counts was highly significant (r = .99; P less than .001). Similarly, the correlation coefficient of GOT activity with percentage of dead spermatozoa was .99 (P less than .001). Percent fertility, fertile egg production, and duration of fertility were negatively correlated with percent dead spermatozoa; 4 = -.55, -.51, and -.44 (P less than .001), respectively.

Animals↗
PubMed1985

Relationship of body fat to fertility in broiler breeder hens.

Sixty-one dwarf broiler breeder hens (58 weeks of age) were utilized to examine relationships among body weight, body fat, oviduct fat, and fertility. Body weight showed a significant (P less than .05) positive relationship to percent body fat (r = +.26). The correlation coefficient between percent body fat and percent oviduct fat was +.26 (P less than .05). Body weight and percent body fat were negatively correlated with fertility; oviduct fat, however, was not significantly correlated to fertility. The adverse effect of body fat on fertility seems to involve a mechanism other than increased fat deposition in the oviduct.

Adipose Tissue↗
PubMed1985

The influence of staining techniques and examiners on evaluation of the morphology of fowl spermatozoa.

A total of 53 dwarf Single Comb White Leghorn males from the relaxed selection mating of low and high body weight lines and a randombred control line were used to determine the influence of technique (eosin-nigrosin smears or collection of spermatozoa on membrane filters) and examiner on the assessment of sperm morphology. There were significant (P less than .05) line, technique, examiner, and technique X examiner interactions for sperm abnormalities. Total abnormal spermatozoa were higher in the high line than in the other two lines, and this was associated with increased midpiece defects and twisted spermatozoa. Eosin-nigrosin smears showed almost twice the percentage of abnormal spermatozoa compared to stained membrane filters.

Animals↗
PubMed1984

Egg characteristics and production efficiency of dwarf (dw) White Leghorn hens divergently selected for body weight.

Egg characteristics, feed efficiency (egg mass/daily feed intake), and performance efficiency (egg mass/body weight) were studied in dwarf White Leghorns after four generations of selection for divergent body weight at 20 weeks of age. Sexual maturity and livability were not significantly different among high (H), low (L), or control (C) lines. Mean 20-week body weights for H, L, and C lines were 1.50 kg, .76 kg, and 1.02 kg, respectively. Daily feed intake, egg mass, egg weight, and yolk, albumen, and shell weights were significantly (P less than .05) different between H and L hens and were directly related to body weight. Percent yolk was greatest and percent yolk mottling and percent albumen were lowest in eggs from L hens. Percent shell was not significantly different among the lines. Albumen quality (Haugh units) was significantly better in eggs from H and L hens than from C hens. Percent hen-day egg production was not significantly different among lines. Feed efficiency was greatest in C hens with both C and L hens significantly more efficient than H hens. Performance efficiencies of C and L hens were significantly better than H hens throughout the experiment, and L hens were significantly more efficient than C hens during peak egg production. These results suggest that there may be minimum body weight requirements for efficient egg production.

Animals↗
PubMed1984

Relationship of fertility to day of insemination during the laying sequence.

Fertility among hens artificially inseminated (AI) at different stages of the laying sequence were compared in two experiments with broiler breed (Experiment 1) and egg-type hens (Experiment 2). The different stages of the laying sequence were prepause (PP)-oviposition without ovulation, pause (P)-no oviposition with or without ovulation, and nonpause (NP)-oviposition with ovulation. There were no significant differences among PP, P, and NP groups for duration or percent fertility in Experiment 1. Fertility and duration were significantly lower in PP than NP in Experiment 2. However, these differences were most likely caused by 36% of the PP hens ovipositing during the time of AI. Time of AI seems to be a more important factor in determining subsequent fertility than the day of AI during the laying sequence.

Animals↗
PubMed1984

Reproductive performance of broiler breeders exposed to cycling high temperatures from 17 to 20 weeks of age.

Forty male and 240 female broiler breeders were placed in cages within environmental chambers (20 males or 40 females per chamber) at 14 weeks of age. Chamber temperatures were maintained at 21.3 +/- 2.5 C, and relative humidity (RH) ranged from 40 to 50%. Ventilation rate was approximately 47.2 liters/sec per chamber, and light was provided from 0600 to 1800 hr. Feed was restricted daily according to industry recommendations, and water was provided ad libitum. From 17 to 20 weeks of age, control (C) chambers were kept at constant 21.0 +/- 1.4 C with 45 +/- 5% RH, and heat-treated (HT) chambers were cycled from 24.4 +/- 5.5 C (45 +/- 5% RH) during 1800 to 0800 hr to 36.0 +/- 2.8 C (15 +/- 5% RH) during 0800 to 1800 hr. Body weights were recorded at biweekly intervals. At 18 and 20 weeks of age, blood samples and rectal body temperatures were obtained randomly from five fasted birds per chamber at 0800 and 1400 hr. From 20 to 60 weeks of age, all birds were kept in individual cages in a conventional fan-ventilated house. Maximum temperature never exceeded 30 C, and average RH was 65.0%. Reproductive parameters were monitored and body weights were obtained at 4-week intervals. There were no significant treatment effects for body weight, body temperature, or differential leukocyte counts. Hematocrits were significantly lower for HT females than controls, and heat treatment did not result in consistent changes in plasma glucose or total proteins.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed1984

Relationships among fertility, sperm storage, and shell quality.

One hundred and nine White Leghorn hens (50 weeks of age) were used to determine the relationships among fertility, sperm storage, and shell quality. The hens were artificially inseminated (AI) on 2 consecutive days with 100 million spermatozoa per insemination. Eggs were collected for 17 days and were classified as hard shell (HS), thin shell (TS), or shell-less (SL). Specific gravity (SG) was determined on HS eggs. All eggs were incubated for 3 days and broken out to determine fertility. The SL eggs were difficult to incubate; therefore, fertility was not obtained for these eggs. Hens producing eggs with SG less than 1.070 showed a significant (P less than .05) decrease in percent and duration of fertility. Specific gravity was significantly correlated with percent fertility, duration of fertility, and fertile egg production. Following the fertility trial, five hens laying HS and five hens laying SL eggs were inseminated as previously described and were killed on the day after the second insemination. The uterovaginal segments were excised, processed for histological evaluation, and stained for either oil red O to quantitate lipid or hematoxylin and eosin to show sperm distribution in uterovaginal sperm-host glands (UV-SHG). Histological examination of the UV-SHG showed that SL hens had a significantly higher percentage of empty glands than HS hens. However, there were no differences between HS and SL hens for UV-SHG lipid deposition.

Animals↗
PubMed1983

Effects of the sex-linked dwarfing gene (dw) on growth and reproduction in white Leghorn hens.

The influence of the dwarfing gene, dw, on growth and reproduction was determined by comparing 1) pure line and reciprocal cross dwarf and normal layers and 2) dwarf and normal full-sib sisters. In Experiment 1, two lines of chickens, the Oregon State University randombred dwarf Leghorn population (D) and Shaver Starcross "288" Leghorns (S), were mated within line and reciprocally to produce normal-sized (SS, SD) and dwarf (DS, DD) female progeny. All progeny were reared similarly until 18 weeks of age when birds were transferred to individual cages. At 18 weeks of age, half the pullets were fed a basal laying ration containing 15% protein while the remaining birds received the basal ration with .1% supplemental methionine. In Experiment 2, full-sib normal and dwarf sisters were obtained by mating hemizygous dwarf females to heterozygous males. Layers were reared in a similar manner to those in Experiment 1 with the exception that all layers received the basal ration with .1% methionine supplemented. Methionine supplementation in Experiment 1 significantly increased egg weights at 35 and 62 weeks of age for all lines and crosses but had no effect on other growth and reproductive traits. Genotype X diet interactions were not observed for any of the measured traits. Normal-sized layers had significantly heavier body weights and longer shank lengths than dwarf layers in both experiments. Dwarf hens in both experiments showed reduced egg production capabilities, although ages at sexual maturity were similar among phenotypes. Dwarf layers laid smaller eggs than normal-sized layers. There were no consistent differences in feed efficiency measures between normals and dwarfs.

Animals↗
PubMed1983

Divergent selection for mature body weight in dwarf White Leghorns. 1. Growth and reproductive responses to selection.

Genetic selection for high (H) and low (L) 20-week body weight (BW) in dwarf White Leghorns was practiced for three generations. The base population was the Oregon State University dwarf Leghorn population (C) selected previously for part year hen-housed egg production (EP), early sexual maturity (SM), and large initial egg weight (EW). Asymmetry of response was observed in both sexes. Realized heritabilities for 20-week BW for H and L males were .49 and .36 and for H and L females were .45 and .79, respectively. Twenty-week BW of the 3rd generation H and L line females were 1.48 and .80 kg, respectively, compared to 1.13 kg for the C line. Similar weights for the males were 1.74, .97, and 1.27 kg for the H, L, and C line, respectively. The H and L lines diverged significantly in 10, 20, 40, and 60-week BW, SM, and EW after one generation of selection and the divergence continued through the third generation. The EP and egg specific gravity did not differ among lines. The C line was intermediate to the selected lines for all traits except EP. The EW at 35 and 60 weeks differed between the H and L lines by 10 g at generation 3 and SM was 149 and 157 days for the H and L lines, respectively.

Animals↗
PubMed1981

Histochemistry of uterovaginal sperm-host glands in Japanese Quail (Coturnix coturnix japonica) with reference to the period of oviposition.

General histochemistry of uterovaginal sperm-host glands (SHG) of Japanese quail was examined in virgin and naturally mated hens and during oviposition in artificially inseminated hens. The SHG tissues were stained for complex carbohydrates with periodic acid - Schiff (PAS); for lipids with oil red O (ORO); and for acid phosphatase (AP) with AS-TR phosphate substrate. Typically, PAS material was absent from SHG cells, SHG showed preferential uptake of ORO, and the stain was seen as discrete droplets with greater accumulation in the apical and basal portions of the epithelia. The SHG showed reduced ORO with an egg in the uterus, and staining was not altered by presence or absence of sperm. All epithelia of the uterovaginal region showed strong AP activity with greatest concentration in the apical portion of the SHG epithelia.

Acid Phosphatase↗
PubMed1980

Effects of progesterone on developing chick embryos.

Experiments were conducted to examine the effects of progesterone on the developing chick embryo with particular attention to the reproductive system. Differing levels of progesterone (0, .5, 1.0, or 2.0 mg) were dissolved in propylene glycol and injected at 4 days of incubation into the yolk sac of eggs from Barred Plymouth Rock females mated to New Hampshire males. Progesterone caused significant reductions in both weight and length and shank weight and length in 18-day-old embryos. Aside from reductions in embryonic growth, progesterone did not cause gross alterations in embryonic development. Progesterone modified neither normal morphology nor differentiation of male or female gonads and associated ductal systems.

Animals↗
PubMed1978

The effect of oviposition on fertility in chickens.

The fertility between the first two eggs of a clutch and between eggs oviposited by the same bird on the same day were compared to determine the effect of oviposition on fertility. No differences in fertility were observed indicating that factors other than oviposition are involved in the mechanism of spermatozoal release and fertility in chickens.

Animals↗