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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Vyhodnocení plodnosti prasnic ve vybraném chovu

NĚMCOVÁ, Eva January 2016 (has links)
The goal of the thesis was to analyse the reproductive performance of sows at a selected farm during years of 2011 - 2015. As a main performance indicator we picked a number of live born piglets per sow and litter. Average number of born alive piglets per litter was 12.54. Highest average was reached by Large White breed with 12.70 piglets in a single parity. Highest average over observed period occurred in 2012 with 13.07 live born piglets. Most productive month was May with 12.81 piglets per parity.First parity produced least amount of piglets (11.94), this metric increased until 4th litter to 13.11, and since 5th parity the parity number slowly decreased. Sows with a shorter farrowing interval (under 145 days) exhibited slightly lower fertility than sows with a longer interval (12.64 and 12.75 live born piglets/parity respectively), the difference being 0.11 piglets per sow. Measuring the effect of length of weaning-to-conception interval, sows with interval of 5 or less days produced more live-born piglets per parity (12.69) than sows with interval of 6 and more days (12.55). As for effect of gestation length, sows with shorter gestation (114 days or less) farrowed more piglets (13.10) than sows with longer gestation (115 days and more 12.14 piglets). Examining gilts, the ones mated in earlier age (under 8.3 months) had smaller average litter size of 11.80 piglets vs. 12.29 piglets for gilts mated after 8.3 months. For 92.05 % of observed sows, a single mating was sufficient, and these had higher farrowing rate of 12.55 vs. 12.35 for sows requiring repeated mating.
2

Analýza ukazatelů reprodukce ve šlechtitelském chovu hus / Analysis of reproduction parameters in the grandparent stock of geese.

ZEMANOVÁ, Lenka January 2014 (has links)
The reproductive efficiency in the grandparent stock and the parent stock of geese was monitored in the thesis. In terms of the grandparent stock, there were found out better values in year 2012 than in year 2013. In 2012, there was a better egg fertilization of 4.61 % (the average was 49.65 %) and hatchability of the put eggs better of 3.83 % (the average was 39.01 %). The hatchability of the fertilized eggs was almost the same in both years. It has the same value of 78.63 %. Best results were proved in strains 1, 3 and 4. Worst values were proved in the strain number 41. The chosen indicators of geese of four ponds were monitored in the parent stock. The average fertilization of eggs was 58.26%; significantly higher value was proved in case of the Jakulský pond (72.34%). The average hatchability of the put eggs reached 46.46%; the highest value was also proved on the Jakulský pond (56.22%). The other ponds have balanced results. The hatchability of the fertilized eggs reached the average value of 79.10%, the highest value was proved on the Lomský pond (84.45%); the second place is represented by the Velebil pond (79.42%). The geese bred on the Lomský pond had eggs with the lowest fertilization, but with the highest percent of hatchability of the fertilized eggs. In case of geese bred on the Velebil pond, there was an increase of the monitored indicators in year 2013 than in 2012. In contrast, the Byňovský pond, the Jakulský pond and the Lomský pond showed an increase of the monitored indicators in 2012. There was a smaller difference of egg fertilization in geese of the Jakulský and the Lomský pond. There was a smaller difference of hatchability indicators of either put or fertilized eggs in geese bred on the Byňovský and the Jakulský pond.
3

Reproductive Peformance of Great Egrets (Ardea alba) at High Island, Texas

McInnes, Andrew 2011 December 1900 (has links)
Despite habitat perturbations and seasonal fluctuations in reproduction, many studies report no significant inter-annual variation in Great Egret reproductive performance. I examined the reproductive performance of Great Egrets (Ardea alba) for two breeding seasons (2009 and 2010) immediately following Hurricane Ike at High Island, Texas. Breeding success, productivity, and mean brood size did not differ between years (U-test, P > 0.05). Fledging success at 21 days showed no significant difference between years, however fledging success at 28, 35, and 42 days decreased significantly between years (~15% reduction at 42 days; U-test, P = 0.027). The number of deaths per nest also differed significantly between 2009 and 2010 (0.36 and 0.95, respectively) (U-test, P = 0.013). Brood-size dependent mortality was also a significant between-year parameter (H test, P = 0.003). Successful nests in 2009 had a brood size range of 2 to 3, and of these nests, 6% and 50% experienced partial brood reduction, respectively; whereas 2010 brood size range for successful nests was 2 to 4, and 0%, 57%, and 100% of these nests, respectively, experienced partial brood reduction. Other parameters examined were water level, temperature, precipitation, prey availability, and human disturbance. I rejected my hypothesis that habitat conditions would be less conducive to high reproductive success in 2009 than 2010, due to the impacts of Hurricane Ike. My results suggest that Great Egrets have bimodal occurrences of nestling death that are expressed as a function of brood size, hatching spread, and nestling age. Reproductive performance studies should continue through at least fledging age (42 days post-hatching for Great Egrets) to better document the reproductive performance, especially by incorporating the apparent behavioral plasticity of nestlings.
4

Reproductive responses of anestrous ewes to the introduction of rams /

Ungerfeld, Rodolfo, January 2003 (has links) (PDF)
Diss. (sammanfattning). Uppsala : Sveriges lantbruksuniv., 2003. / Härtill 6 uppsatser.
5

Porovnání chovu dvou plemen ovcí chovaných ve stejné oblasti / The comparison of two breed of sheeps reared in the same area

RAABOVÁ, Alena January 2011 (has links)
The comparison of two breed of sheeps reared in the same area. The aim of the master thesis was the evaluation of the level of the reproductive and the productive traits by the two breeds of sheeps in the area of Novohradské Hory Mts. The examination was conducted from 2006 to 2009. The farm recording and the author´s personal observation were both used for the evaluation. The following traits were recorded: insemination, fertility, intensity, lamb rearing, infertility, mortality. The production traits recorded were the weight of the wool and weight gain in 100 days after the birth. The following results (arithmetic means) were obtained: the rate of insemination by the Valaška breed was 94.3 %, fertility 168.4 %, intensity 158.5 % and the lamb rearing 150.2 %. The rate of infertility was 5.9 % and rate of mortality 5.1 %. The average wool weight was 2.21 kg and the weight gain 175.8 g day-1. By the Merinolandschaf breed, the rate of insemination was 87 %, fertility 134.4 %, intensity 116.1 % and the lamb rearing 101.5 %. The rate of infertility was 13.2 % and rate of mortality 8.8 %. The average wool weight was 4.2 kg and the weight gain 236.9 g day-1. The herd A revealed better results as regards the reproduction traits while the herd B revealed better results concerning the production traits. The significant differences between the examined herd of Valaška sheeps and the Czech population were found in the fertility, intensity and the lamb rearing (T test). By the Merinolandschaf herd, the significant differences from the Czech population were found by the weight gains (T test). The significant differences between the two breeds were found in the fertility, intensity and lamb rearing (T test).
6

Synchronization and Resynchronization of Ovulation and Timed Insemination in Lactating Dairy Cows and Heifers

Peeler, Iris Dawn 29 April 2004 (has links)
This study was conducted to evaluate the efficacy of intravaginal progesterone (P4) inserts (CIDR) in synchronization protocols combined with timed artificial insemination (TAI) as related reproductive performance. In the first study, heifers were synchronized with CIDR inserts followed by TAI. Heifers in the estradiol cypionate (ECP) group were synchronized with a combination of ECP, CIDR, prostaglandin (PGF2α), and ECP (CIDR-ECP), while the gonadotropin-releasing hormone (GnRH) group was synchronized using a combination of ECP, CIDR, PGF2α, and GnRH (CIDR-GnRH). All heifers were bred at either 48, 56, or 72 hours (h) after CIDR removal. Overall pregnancy rate (PR) for synchronized heifers was 60.1%, and embryo survival rate (ESR) was 98%. Pregnancy rate for CIDR-ECP treated heifers was influenced by artificial insemination (AI) time. In conclusion, ECP or GnRH may be used effectively in a CIDR-based TAI program in heifers. In the second study, cows were synchronized with CIDR devices or Ovsynch. The CIDR group received a combination of ECP, CIDR, PGF2α, and GnRH, while the Ovsynch group was synchronized using a combination of GnRH and PGF2α. Cows were bred at either 0, 8, or 24 h after the final GnRH injection. Overall PR for first service was 30.5% with ESR of 82.8%. Overall resynchronization PR was 35.1% with an ESR of 84.8%. In conclusion, Ovsynch and CIDR-based protocols are equally effective in synchronizing ovulation in a TAI program and resulted in comparable PR. / Master of Science
7

Reproduction and Enzyme Detoxification Activities in Mouse Lines Selected for Response to Fescue Toxicosis

Wagner, Catherine Ann Robertson 21 May 1999 (has links)
In previous work, mouse lines were selected for resistance (R) or for susceptibility (S) to fescue toxicosis based upon reductions in post-weaning growth rate caused by an endophyte-infected diet. The first objective of the current experiment was to determine whether long term reproduction of S mice was more severely depressed than that of R mice by the toxic diet. The second objective was to quantify glutathione-S-epoxytransferase (GST) and uridine diphosphate glucuronosyl-transferase (UDPGT) activities in R and S dams form the experiment and to determine whether reproduction during continuous cohabitation and liver detoxification enzyme activities were correlated within line x diet groups. Effects of the toxic diet were detectable within the first litters produced. Reproduction was more seriously influenced by the toxic diet within the S line than within the R line when these measures were compared within four equal time phases. The effects of the toxic diet on reproduction were greatest early in the experiment; by the fourth time phase differences among line x diet groups, with the exception of litter weight, were not significant. Percentage differences in total reproduction were greater between S mice fed the non-toxic diet and S mice fed the toxic diet than those between the R mice fed the non-toxic and toxic diets. Averaged across diets, GST activities were higher in R mice, but UDPGT activities were not significant. Within R line mice, GST was correlated with three reproductive measures, but UDPGT activity was not correlated with reproduction within any line x diet group. / Master of Science
8

LONG-TERM EFFECTS OF DIETARY COPPER SOURCE AND LEVEL ON PERFORMANCE AND HEALTH OF SOWS AND PIGLETS

Lu, Ning 01 January 2018 (has links)
The objectives of this study were to investigate the long-term effects of feeding increasing supplemental levels (20, 120, or 220 mg/kg) of dietary copper (Cu) as tribasic copper chloride (TBCC) or copper sulfate (CuSO4) on performance, antioxidant status, nutrient digestibility, and trace mineral deposition of sows and piglets; as well as to assess nursery dietary Cu levels on growth performance and response to immunological challenge in nursery pigs from sows fed either high or low Cu diets. In the long-term sow experiment, sows fed TBCC diets had greater adjusted weaning weight for litter and piglet (P < 0.10), as well as adjusted litter and piglet weight gain (P < 0.10) when compared to sows that received CuSO4 diets. Increasing dietary Cu level linearly increased live born piglet weight (P = 0.06). Sows fed TBCC diets had lower apparent total tract digestibility (ATTD) of ether extract (P = 0.01) during late gestation, but greater ATTD of dry matter, nitrogen, and phosphorous during lactation (P < 0.05). Increasing Cu levels linearly increased dry matter digestibility in lactating sows (P = 0.02). Milk from sows fed TBCC diets had a greater concentration of protein (P = 0.02) than that from sows fed CuSO4 diets. Increasing Cu levels increased levels of milk fat and Cu (linear, P < 0.05); but linearly decreased lactose and Zn levels (P < 0.05). Lactating sows fed TBCC diets had a greater activity of Cu/Zn superoxide dismutase (SOD) and ceruloplasmin in serum than those fed CuSO4 diets (P < 0.05). Increasing dietary Cu levels increased total and Cu/Zn SOD activity for lactating sows (linear, P < 0.05). Sows fed TBCC diets had lower concentrations of Cu (P = 0.04), but higher concentrations of iron and manganese (P < 0.05) in the liver, when compared to those fed with CuSO4 diets. In addition, liver Cu concentrations increased with increasing dietary Cu levels (linear and quadratic, P < 0.05). Increasing dietary Cu levels resulted in the elevation of concentrations and contents of Cu in the liver of weanling piglets (linear, P < 0.0001). In the nursery pig experiment, pigs from sows fed 120 mg/kg Cu diets had greater ADG from d 0 to 14 (P < 0.05), and tended to have greater ADG in the overall period (P < 0.08), when compared to pigs from sows fed 20 mg/kg Cu diets. During the lipopolysaccharide challenge period, the challenged pigs from sows fed 120 mg/kg Cu had a greater overall rectal temperature than those from sows fed 20 mg/kg Cu (P = 0.01). Also, the challenged pigs fed with 220 mg/kg Cu diets had greater serum tumor necrosis factor-alpha concentration over time as compared to those fed 20 mg/kg Cu diets (P = 0.03). In summary, the TBCC may be a superior Cu source compared to CuSO4 regarding reproductive performance, and higher dietary Cu levels result in greater birth weight of piglets; furthermore, high Cu levels in sow and nursery diets promote growth performance of nursery pigs and affects their responses to immunological challenge.
9

Effects of Rumen Protein Degradability on Rumen Characteristics, Milk Production and Reproductive Performance in Holstein Dairy Cows

Figueroa, Mario Raul 01 May 1992 (has links)
Three non-lactating Holstein cows fitted with rumen cannula were used to determine crude protein and dry matter rate of disappearance of two protein supplements: 1) soybean meal and 2) bypass protein blend by using the in situ bag technique. Rate disappearance (%/hr) was higher for soybean meal. Two collection periods were completed using 6 cows with a minimum of 21 d adaptation to the treatment top dressed on to the total mixed ration. Ruminal concentration of ammonia N, blood ammonia, and urea did not differ between treatments. Total concentration of volatile fatty acids was higher for bypass protein blend-fed cattle as well as percent molar concentration of propionate, butyrate, and valerate, while pH was lower. Total protozoa, and total and cellulolytic viable bacteria populations did not differ. Four of the cows received a dose of 5 ml of Prostaglandin F,a. Blood and cervical muc us samples obtained showed no difference in blood ammonia and urea concentration . Forty-six Holstein cows were assigned to one of the two treatments (top dressed on the t otal mixed ration), according to parity during the following 125 d postpartum. Daily dry matter intake and milk production were recorded. Feed, orts, and feces were sampled. Milk samples were collected weekly and analyzed for components. Percent lactose and solid non-fat showed higher for cattle fed the bypass prorein blend. Starting on day 10 postpartum, cows were observed for signs of estrus and bred at first estrus observed after 45 d postpartum. Cervical mucus and blood collected at first standing estrus, and first, seco nd, and third service, did not show a significant difference in urea concentration between rations. Twice-weekly collected blood samples showed similar monthly mean concentration of ammonia, urea, and progesterone profile for both treatment groups. Percent pregnancy, services per pregnancy, first service pregnancy and embryo mortality showed no significant difference. Motility and survivability of bull sperm were evaluated by incubating thawed semen in different levels of previously observed and/or ammonia. physiological There were no concentrations of urea significant treatment differences observed. Detrimental effects of treatment on sperm were not detected.
10

Ecophysiological studies of body composition, body size and reproduction in polar bears

Atkinson, Stephen Noel 01 January 1996 (has links)
For the polar bear (<i>Ursus maritimus</i>), a terrestrial carnivore on the highest trophic level in the Arctic marine ecosystem, periods of nutritional restriction or fasting are a characteristic feature of an annual cycle. The overall objective of my thesis was to examine some of the effects of such a 'feast-or-fast' feeding pattern on the body composition, body size and reproductive performance of this Holarctic ursid. As a reproductive strategy, pregnant polar bears occupy maternity dens for up to 6 months between late summer and spring. While in dens, maternal nutrient stores meet all maintenance energy requirements and sustain the nutritional demands of gestation and early lactation. I quantified the nutritional costs of this prolonged 'reproductive fast' in polar bears and examined the effects of variation in maternal body condition on reproductive performance. While fasting, body mass decreased by 43% and of the change in body energy content 93% was attributable to loss of fat. Bears that were fatter priorto denning produced heavier cubs, which would be more likely to survive. Much of the variation in body condition prior to denning was accounted for by age, older females being in better condition. Using an index of milk quality that was closely related to daily milk energy yield, I investigated the independent effects of maternal body condition and age on lactation. Irrespective of condition, older bears tended to produce higher quality milk. While lactation in polar bears is clearly sensitive to body condition, these results also provide strong support for an age-specific increase in reproductive effort among females. Body size is typically a strong determinant of male reproductive success in polygynous mammals such as polar bears. Consequently, theory predicts that mothers in good condition should invest more in male than female offspring in-order to produce large adult males. An underlying assumption of this theory, however, is that early differences in body size among male offspring, such as those apparent by the end of maternal care, will affect their relative adult body size. I tested the validity of this assumption in polar bears and found that, in comparison to females, variation in body size among 2-year-old males was a weak determinant of adult size. I suggest that, in comparison to females, a longer period of growth after maternal care may predispose the adult size of males to a greater degree of environmentally mediated variation. This lack of persistence in relative body size would limit the ability of mothers to affect the adult size of their male offspring, and thus reduce the effectiveness of sex-biased maternal investment as a reproductive strategy in polar bears. One of the principle physiological adaptations enabling animals to go without food for prolonged periods seems to be a heightened ability to minimize the net catabolism of body protein. I quantified changes in the body composition of free-ranging polar bears during the ice-free season. In contrast to previous studies on fasting bears, catabolism of protein appeared to meet a significant proportion of maintenance energy demands in some individuals. (Abstract shortened by UMI.)

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