Ram mating performance in Border Leicesters and related breed types. 3. Relationships of ram serving capacity, testis diameter, liveweight, breed and age with flock fertility

1989 ◽  
Vol 29 (1) ◽  
pp. 17 ◽  
Author(s):  
SA Barwick ◽  
RJ Kilgour ◽  
DG Fowler ◽  
JF Wilkins ◽  
WR Harvey
Keyword(s):  
Pregnancy Rate ◽  
Testicular Tissue ◽  
Interaction Effects ◽  
The Other ◽  
Mating Performance ◽  
Related Breed

Relationships of ram serving capacity (a measure of serving frequency in pen tests), testis diameter, liveweight, breed and age with flock fertility were studied in 40 rams joined individually for 7 days at high ewe:ram ratios. Rams were either Border Leicester, BLI (a high prolificacy line derived from the Border Leicester and Merino and since released as the Glen Vale breed) or BLI x Border Leicester, and aged either 1.5 or 2.5 years. Joinings were over 2 periods, 2-9 April or 16-23 April. Breed, age, period and interaction effects were also examined. On average (± s.e.), the number of ewes with mating marks in 7 days increased by 2.03 ± 0.52 ( P < 0.001) per serve per hour of serving capacity and by 0.40 ± 0.18 ( P < 0.05) per kg liveweight. Relationships with pregnancy rate in marked ewes differed between classes of rams. Larger testes were of most benefit when rams were of high serving capacity ( P < 0.0 1 ) or low liveweight (P<0.01). Only serving capacity was related to number of ewes pregnant, the number increasing by an average (± s.e.) of 1.73 ± 0.57 ewes per serve per hour (P<0.01). This suggests that a ram's capacity for more frequent service was more important to fertility than was extra testicular tissue. BLI x Border Leicester, BLI, and 2.5-year-old Border Leicester rams impregnated 30-40% more ewes than did 1.5-year-old Border Leicester rams. We estimate that the 1.5-year-old Border Leicester rams could be satisfactorily joined to about 46 ewes and the other rams to about 60 ewes.

EFFECT OF FEEDING ETHINYLOESTRADIOL FOR VARIOUS PERIODS BEFORE MATING ON REPRODUCTION IN THE HAMSTER

1972 ◽  
Vol 70 (3) ◽  
pp. 582-590
Author(s):  
B. K. Davis ◽  
I. Noske ◽  
M. C. Chang
Keyword(s):  
Single Dose ◽  
Pregnancy Rate ◽  
Fertility Control ◽  
Normal Pregnancy ◽  
Oestrous Cycle ◽  
The Other ◽  
Feeding Schedule ◽  
Crown Rump Length ◽  
Essentially Normal ◽  
Effect Of Feeding

ABSTRACT Ethinyloestradiol (EO) fed for various periods before mating to female hamsters affected the timing of mating and pregnancy rate. Slight effects on ovulation, foetal-crown rump length and resorption may have occurred, but effects on implantation were not apparent among pregnant hamsters. The response observed depended upon the feeding schedule adopted: hamsters fed 2.5 mg EO in a single dose, on day 3 before mating, mated normally but had a significantly lower pregnancy rate; on the other hand, animals fed 2.5 mg EO (0.21 mg/day) over three oestrous cycles, days 14–3 before mating, showed variations in the time of mating but had an essentially normal pregnancy rate; and, a group of hamsters who received the same total amount of EO (0.63 mg/day) over one oestrous cycle, days 6–3 premating, showed untowards effects by the steroid on both the timing of mating and pregnancy rate. The implications of these results are considered in relation to fertility control.

Modification of spermatozoa quality in mature small ruminants

2012 ◽  
Vol 24 (1) ◽  
pp. 13 ◽  
Author(s):  
G. B. Martin ◽  
T. Jorre de St Jorre ◽  
F. A. Al Mohsen ◽  
I. A. Malecki
Keyword(s):  
Large Body ◽  
Small Ruminants ◽  
Cell Loss ◽  
Testicular Tissue ◽  
The Other ◽  
Sperm Production ◽  
Testicular Mass ◽  
Other Hand ◽  
Sperm Survival ◽  
Sperm Output

This review is based largely, but not entirely, on the assumption that gamete quality is directly linked to sperm output and thus testicular mass, an approach made necessary by the absence of a large body of data on factors that affect gamete quality in ruminants. On the other hand, there is a change in the efficiency of sperm production per gram of testicular tissue when the testis is growing or shrinking, a clear indicator of changes in the rates of cell loss during the process of spermatogenesis, probably through apoptosis. We therefore postulate that the spermatozoa that do survive when the testis is shrinking are of a lower quality than those that are produced when the testis is growing and the rate of sperm survival is increasing. In adult small ruminants in particular, testicular mass and sperm production are highly labile and can be manipulated by management of photoperiod (melatonin), nutrition, genetics and behaviour (‘mating pressure’). Importantly, these factors do not act independently of each other – rather, the outcomes in terms of sperm production are dictated by interactions. It therefore seems likely that spermatozoa quality will be affected by these same factors, but definitive answers await detailed studies.

scholarly journals Does Technology Impact on Teaching Styles or Do Teaching Styles Impact on Technology in the Delivery of Higher Education?

10.28945/2792 ◽  
2004 ◽  
Author(s):  
Tony Jewels ◽  
Carmen de Pablos Heredero ◽  
Marilyn Campbell
Keyword(s):  
Higher Education ◽  
Distance Education ◽  
Case Studies ◽  
Teaching Styles ◽  
Interaction Effects ◽  
The Other ◽  
Web Based ◽  
Other Hand ◽  
Practice Teaching ◽  
Institutional Adoption

Although there are many teaching styles in higher education, they can usually be reduced to two: the traditional, on campus attendance, lecturing, student-passive style and the newer, distance education, self-paced, student-active style. It is the contention of this paper, illustrated by two case studies of one Spanish and one Australian university, that the differences in technology seem to have evolved due to these different teaching styles. On the other hand, both institutions seem to be in the same stage of technological implementation, although the technological product appears different. A discussion is provided to consider the interaction effects in practice, teaching styles and institutional adoption stage on web based technologies in these two universities.

scholarly journals Loneliness, Family Communication, and School Adjustment in a Sample of Cybervictimized Adolescents

2020 ◽  
Vol 17 (1) ◽  
pp. 335 ◽  
Author(s):  
Elizabeth Cañas ◽  
Estefanía Estévez ◽  
Celeste León-Moreno ◽  
Gonzalo Musitu
Keyword(s):  
Gender Differences ◽  
Family Communication ◽  
School Adjustment ◽  
Academic Competence ◽  
Interaction Effects ◽  
The Other ◽  
Social Variables ◽  
Open Communication ◽  
Individual Family ◽  
The One

The objective of this study was to compare individual, family, and social variables, such as the perception of loneliness, family communication, and school adjustment in a sample of 2399 Andalusian (Spanish) adolescents aged 12 to 18 (M = 14.63, SD = 1.91) suffering from cybervictimization (low, moderate, and high). The results show that adolescents suffering from high cybervictimization report more loneliness, more problematic communication with both parents, and worse school adjustment than the rest of the groups. Regarding gender, differences are observed in open communication with the mother and in the dimensions of school adjustment, being more favorable for girls. However, there were no significant differences between girls and boys in the loneliness variable. The interaction effects indicate, on the one hand, that female severe cybervictims present more avoidant communication with the mother than the other groups, and, on the other hand, that male cybervictims of all three groups and female severe cybervictims have lower academic competence than the group of female low cybervictims, followed by female moderate cybervictims. These data support the idea that, depending on its intensity and duration, cybervictimization affects girls and boys differently in terms of individual, family, and social variables.

Effect of Relative Positions of Segments on Strength of the Mueller-Lyer Illusion

1971 ◽  
Vol 33 (3_suppl) ◽  
pp. 1051-1058 ◽  
Author(s):  
Clive M. Davis ◽  
Marshall H. Segall
Keyword(s):  
Visual Field ◽  
Depth Perception ◽  
Interaction Effects ◽  
The Other ◽  
Relative Height ◽  
Lyer Illusion ◽  
Main Effect ◽  
Depth Cue

Segall, Campbell, and Herskovits (1966) postulated that the Mueller-Lyer illusion results from the misapplication of normally valid visual inference habits related to depth perception. To test the hypothesis that the depth cue of the relative height of the Mueller-Lyer segments in the visual field affects susceptibility, 100 Ss were presented two identical sets of 15 slides of Mueller-Lyer stimuli, one set with the >—–< above the <——> and the other set in the reverse orientation. Placement of the >—–< above the <—–> produced significantly greater illusion susceptibility, as predicted by the depth cue hypothesis. Females were more susceptible than males, but there were no interaction effects of sex with figure orientation or trials nor a main effect for trials. The results were interpreted as supporting an empiricistic explanation of the Mueller-Lyer illusion.

scholarly journals Effect of different endometrial preparation protocols on pregnancy outcomes in frozen- embryo transfer cycles: a retrospective cohort study

2021 ◽  
Author(s):  
Yue Qian ◽  
Qi Wan ◽  
Xiao-Qing Bu ◽  
Tian Li ◽  
Xiao-Jun Tang ◽  
...  
Keyword(s):  
Logistic Regression ◽  
Pregnancy Rate ◽  
Live Birth ◽  
Pregnancy Outcomes ◽  
Multiple Logistic Regression Analysis ◽  
Clinical Pregnancy ◽  
The Other ◽  
Multiple Logistic Regression ◽  
Endometrial Preparation ◽  
Natural Cycles

Abstract Background Owing to the crucial role the endometrium plays in embryo implantation, the four main endometrial preparation protocols have become important factors in the study of pregnancy outcomes in the FET cycles. Previous studies have shown that the best of these four protocols remains controversial for women undergoing FET. Methods A total of 10333 FET cycles from January 2018 to December 2018 were analyzed in this study. They were categorized into four groups according to endometrial preparation regimen: natural cycles (Group NC,n = 815), hormone replacement therapy cycles (Group HRT ,n = 6434), GnRH agonist artificial cycles (Group GAC,n = 1392) and ovarian stimulation cycles (Group OC, n = 1692). All patients were followed up for at least 1 year. Pregnancy outcomes were compared between the four groups and multiple logistic regression models were used to adjust for the effects of confounding factors. Results The ectopic pregnancy rate (P = 0.627) and miscarriage rate (P = 0.164) were not statistically significant between the four groups. Moreover, biochemical pregnancy rate, clinical pregnancy rate and live birth rate in the NC group were not statistically significant compared to the other three groups. After adjusting for covariates, multiple logistic regression analysis showed no statistical significance in pregnancy outcomes in the HRT, GAC and OC groups compared to the NC group.And the adjusted OR for live births was 0.988 (95 % CI0.847-1.152) for the HRT group, 0.955 (95 % CI0.795-1.146) for the GAC group,0.898 (95 % CI0.754-1.070) for the OC group. Conclusions Our study showed that natural cycles have similar pregnancy outcomes in terms of clinical pregnancy and live birth to the other three endometrial preparation options. As it has other advantages, the natural cycle protocol can therefore be the recommended option for endometrial preparation in the FET population.

scholarly journals Role of Fiber Finish in the Conversion of Fiber to Nonwovens — Part II: Finish Performance as a Mechanical Processing Aid in Carding

2002 ◽  
Vol os-11 (1) ◽  
pp. 1558925002OS-01 ◽  
Author(s):  
Abdelfattah M. Seyam ◽  
Thomas J. Proffitt ◽  
Murali Velmurugan
Keyword(s):  
Process Parameters ◽  
Interaction Effects ◽  
The Other ◽  
Mechanical Processing ◽  
Fiber Breakage ◽  
Static Charge ◽  
Charge Generation ◽  
Other Hand ◽  
Different Levels

This part of the study aims to investigate the role of fiber finish in the carding process. Two different fibers, namely, polyester and polypropylene with different levels of finish and finish uniformity, are processed on carding machine. Certain key response parameters such as fiber breakage, fiberweb cohesion, fiberweb uniformity, nep generation and static charge generation, are chosen and the effect of finish level and its uniformity on these parameters are observed. The finish performance is also studied for possible interaction effects between other carding process parameters. The results indicate a significant effect of finish add-on percentage on most of the response parameters. On the other hand, finish uniformity was found to have less influence on the response parameters. It has also been found that the response parameters behave differently for each of the two fibers and hence results based on one type of fiber may not be applicable for another.

11 FERTILITY OF FRESH AND FROZEN - THAWED EPIDIDYMAL STALLION SPERM WITH OR WITHOUT EXPOSURE TO SEMINAL PLASMA

2007 ◽  
Vol 19 (1) ◽  
pp. 124 ◽  
Author(s):  
A. Heise ◽  
D. Gerber ◽  
D. H. Volkmann ◽  
W. Kähn ◽  
N. K. Brouwer
Keyword(s):  
Pregnancy Rate ◽  
Seminal Plasma ◽  
Animal Health ◽  
Skim Milk ◽  
The Other ◽  
Epididymal Sperm ◽  
Chi Square ◽  
Estrous Cycles ◽  
Preliminary Results ◽  
Chi Square Test

The aim of this study was to determine if the addition of equine seminal plasma to epididymal semen enhances its fertility before or after freezing. Thirty-two mares were randomly assigned to 5 stallions; 3 stallions were kept in Pretoria, each having 7 mares, and 2 stallions were kept at Cornell, one having 6 mares and the other 5. Mares were synchronized using 10 daily IM progesterone and estradiol injections; an Ovuplant® implant (26 mg of deslorelin; Peptech Animal Health, Sydney, NSW, Australia) was inserted under the mucosa of the vaginal vestibulum once a follicle reached a diameter of 35 mm; implants were removed after ovulation. Mares were inseminated 30 h after implant insertion. Each insemination dose consisted of 200 million progressively motile sperm and was deposited into the uterine body. Following insemination, mares were examined for ovulation at 6 hourly intervals. Fourteen days after ovulation, mares were examined for pregnancy by transrectal ultrasonography and treated with PGF2α to induce the next estrus. Seminal plasma was collected from the stallions used in the trial prior to castration, frozen, and stored. In Pretoria, stallions were castrated and one epididymal tail was flushed with seminal plasma and the other with skim milk extender; in the first cycle, half of the mares were inseminated with one of the two sperm samples. In Cornell, testes of each stallion were removed 3 weeks apart, and all mares were inseminated first with one and 3 weeks later with the other semen sample. Mares were inseminated during consecutive estrous cycles using the following sperm types: fresh epididymal sperm that had been exposed to seminal plasma (G1: 4 mares per stallion in Pretoria, 6 and 5 mares per stallion at Cornell); fresh epididymal sperm that had never been exposed to seminal plasma (G2: 3 mares per stallion in Pretoria, 6 and 5 mares per stallion at Cornell); frozen–thawed ejaculated sperm (G3); frozen–thawed epididymal sperm that had been exposed to seminal plasma prior to freezing (G4); and frozen–thawed epididymal sperm that had never been exposed to seminal plasma (G5). The results of inseminations with fresh epididymal semen (G1–2) of 5 stallions and the preliminary results of inseminations with frozen–thawed epididymal semen (G3–5) of 2 stallions are summarized in the Table 1. Cycles where ovulation did not occur within 12 h after insemination were excluded. The pregnancy rate of mares inseminated with fresh epididymal sperm of G1 was significantly higher (chi-square test; P &lt; 0.05) than that of mares of G2. The pregnancy rate of mares inseminated with frozen–thawed ejaculated semen (G3) was similar to that of mares inseminated with frozen–thawed epididymal semen of G4 and G5 (P = 0.3). Based on these preliminary results, we conclude that the fertility of fresh epididymal sperm can be enhanced by exposure to equine seminal plasma. To determine if the same holds true for frozen–thawed epididymal sperm, more inseminations must be performed. Table 1.Results of inseminations with various semen types

11 Invivo-derived embryo pregnancy rates at Maddox Dairy from 2008 to 2018

2020 ◽  
Vol 32 (2) ◽  
pp. 130
Author(s):  
D. Demetrio ◽  
A. Magalhaes ◽  
M. Oliveira ◽  
R. Santos ◽  
R. Chebel
Keyword(s):  
Pregnancy Rate ◽  
Embryo Transfer ◽  
Milk Production ◽  
Pregnancy Rates ◽  
The Other ◽  
Lactating Cows ◽  
June July August ◽  
June July ◽  
Management Changes ◽  
July August September

Maddox Dairy, located in Riverdale, CA, USA, is a Holstein herd that milks 3500 cows with a 305-day mature-equivalent milk production of 12 800 kg, and they have been producing high genetic animals by embryo transfer (ET) since the early 1980s. Invivo-derived embryos from Holstein donors were transferred fresh (grade 1 or 2) or frozen (grade 1), at morula (4), early blastocyst (5), or blastocyst (6) stage, to virgin heifers (VH, natural oestrus, 13-15 months old) or lactating cows (LC, Presynch-Ovsynch, 86 days in milk, first or second lactation) 6 to 9 days after oestrus. Pregnancy diagnosis was done by transrectal ultrasonography at 32-46 days in VH and by the IDEXX PAG test at 30 days in LC. June, July, August, September, and October were called critical months (first service AI conception rate drops below 44%) and compared with the other months. The data from 32 503 ETs between January 2008 and December 2018 are summarised on Table 1. Pregnancy rates (PR) are lower for LC recipients than for VH. Embryo transfers performed 7 or 8 days after oestrus had higher PR in both types of recipients and embryos, but Day 6 and 9 oestrus are also used with fair results. The season does not seem to affect PR. There is not enough difference in the combination of stage and days from oestrus for invivo-derived embryos. These numbers do not belong to a planned experiment. Several management changes during the years were made, which make it very difficult to apply statistical methods to analyse the data correctly. They are used as a tool to make decisions in an attempt to improve future results. Table 1.Pregnancy rate (PR) of virgin heifers (top) and lactating cows (bottom)-fresh (SH) and frozen (OZ) invivo-derived embryo transfer1 Heat-months SH-ST4 SH-ST5 SH-ST6 SH-All OZ-ST4 OZ-ST5 OZ-ST6 OZ-All PR% n PR% n PR% n PR% n PR% n PR% n PR% n PR% n Heifers 6 d-CM 62 934 66 243 68 69 63 1246 56 473 58 219 62 42 57 734 6 d-OM 62 1623 67 489 69 211 64 2323 56 600 55 296 48 137 55 1033 6 d-T 62 2557 67 732 69 280 63 3569 56 1073 57 515 51 179 56 1767 7 d-CM 64 1506 68 495 67 221 65 2222 60 822 62 340 63 156 61 1318 7 d-OM 66 2723 68 1021 69 510 67 4254 57 1120 59 581 57 231 58 1932 7 d-T 66 4229 68 1516 69 731 67 6476 58 1942 60 921 60 387 59 3250 8 d-CM 65 1348 64 518 67 322 65 2188 59 595 64 258 63 108 61 961 8 d-OM 66 2166 68 886 70 510 67 3562 61 770 60 364 51 130 60 1264 8 d-T 66 3514 67 1404 69 832 66 5750 60 1365 62 622 56 238 60 2225 9 d-CM 60 109 56 43 70 20 60 172 60 5 33 6 50 4 47 15 9 d-OM 58 129 63 57 60 40 60 226 63 16 50 18 75 4 58 38 9 d-T 59 238 60 100 63 60 60 398 62 21 46 24 63 8 55 53 All-CM 64 3897 66 1299 67 632 65 5828 58 1895 61 823 63 310 60 3028 All-OM 65 6641 67 2453 69 1271 66 10 365 58 2506 58 1259 53 502 58 4267 All-T 65 10 538 67 3752 69 1903 66 16 193 58 4401 60 2082 57 812 59 7295 Lactating cows 6 d-CM 54 265 48 86 50 12 53 363 38 141 31 77 50 10 36 228 6 d-OM 49 463 52 203 45 56 50 723 46 101 48 54 59 27 48 182 6 d-T 51 728 51 289 46 68 51 1086 41 242 38 131 57 37 42 410 7 d-CM 54 755 59 274 56 103 55 1137 43 928 48 450 43 192 45 1570 7 d-OM 55 914 66 367 54 109 58 1393 46 1052 45 564 47 353 46 1969 7 d-T 55 1669 63 641 55 212 57 2530 45 1980 46 1014 46 545 45 3539 8 d-CM 63 252 68 82 76 33 65 368 48 219 56 80 42 33 50 332 8 d-OM 61 257 64 161 53 47 61 466 50 191 53 77 56 16 51 284 8 d-T 62 509 65 243 63 80 63 834 49 410 55 157 47 49 50 616 All-CM 56 1272 58 442 60 148 57 1868 44 1288 47 607 43 235 45 2130 All-OM 55 1634 62 731 51 212 56 2582 47 1344 46 695 48 396 47 2435 All-T 55 2906 60 1173 55 360 57 4450 45 2632 47 1302 46 631 46 4565 1ST=stage; CM=critical months (June, July, August, September, and October); OM=other months.

scholarly journals Response of Yield and Yield Components of Tef [Eragrostis tef (Zucc.) Trotter] to Tillage, Nutrient, and Weed Management Practices in Dura Area, Northern Ethiopia

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Gebreyesus Brhane Tesfahunegn
Keyword(s):  
Grain Yield ◽  
Weed Control ◽  
Yield Components ◽  
Scientific Information ◽  
Interaction Effects ◽  
The Other ◽  
Eragrostis Tef ◽  
Northern Ethiopia ◽  
Leaf Stage ◽  
Yield And Yield Components

The low average grain yield (0.7 ton ha−1) of tef in Ethiopia is mainly attributed to low soil fertility, and inappropriate tillage and weeds control practices. Despite this, limited scientific information has been documented so far on their interaction effects on tef crop productivity in northern Ethiopia. The objective of this study was to assess the separate and interaction effects of tillage, fertilizer, and weed control practices on tef yield and yield components in the conditions of northern Ethiopia. A two-year study (2008-2009) was conducted using split-split-plot design with three replications. In the main plot, three tillage treatments: conventional tillage (6 times tillage passes) (T1), four times tillage passes (T2), and reduced tillage (single tillage pass at sowing) (T3) were applied. The fertilizer treatments in the subplots were: no fertilizer (F1); 23 kg N ha−1 (F2); 23 kg N ha−1 and 10 kg P ha−1 (F3); 23 kg N ha−1 and 2.5 ton manure ha−1 (F4); and 2.5 ton manure ha−1 (F5). The sub-subplot weed control treatments included farmer weed control practice or hand weeding (W1); 2,4 D at 0.75 kg ha−1 at five-leaf stage; 2,4 D at 0.75 kg ha−1 at six-leaf stage; 2,4 D at 1.5 kg ha−1 at five-leaf stage; and 2,4 D at 1.5 kg ha−1 at six-leaf stage. This study showed that the separate and interaction effects of tillage, fertilizer, and weed control practices significantly affected tef crop yield and yield components in both crop seasons. T2 increased tef yield by >42% over the other tillage and F3 increased yield by >21% over the other fertilizer treatments. Grain yield increased by >23% due to W1. This study thus suggested that promising treatments such as T2, F3, and W1 should be demonstrated at on-farm fields in order to evaluate their performance at farmers’ conditions.

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