Hatching

The study was done in the ostrich farm in Patos – Albania. One egg setting was monitored, through dividing the eggs into three groups according to their age, as following: 20–30 days old, 10–20 days old and 1–10 days old. All the 197 eggs were marked according to their age of storage. During the hatching process, the respective parameters, such as: the total eggs set, fecundity, embryonic mortality, weight loss, were followed, recorded and monitored. Related to all these parameters, the appropriate incubation regime was selected. The average weight loss of all the eggs, no matter of their age, resulted to be 5.3%, or 0.5% more than the standard. The reason of the high embryonic mortality (40.7%) relates mainly with the very long time and improper storage condition of the eggs before setting. While, on the other hand, the very high level of egg sterility (42.6%), relates with several factors, where the main two ones are the transport stress of the breeders, because they have just arr...

Effects of high and low cast feed on the hatching and survival rate of freshwater prawn Macrobrachium rogenbergii larvae were observed. Three different treatments (T1, T2 and T3) were designed with three types of feeds as follows: T1, Saudi-Bangla Prawn feed 100%; T2,Saudi-Bangla prawn feed 50% + low cast feed 50%; T3, low cast feed 100%. The prawns were reared from February to May 2001 until they became mature enough to breed. The results showed that the average value of hatching rate was 90.14%, 89.69% and 89.29% and the average survival rate of larvae was 39.44%, 38.88% and 38.33% in Tl, T2 and T3 respectively. There were no significant differences (P>0.05) between hatching and survival rate of M. rogenbergii from different feeding trails. The price of Saudi-Bangla prawn feed was very high (Tk. 24/kg) than the local feed (Tk. 14/kg). So, use of local feed was recommended for M. rogenbergii brood rearing.

The Indian chameleon, Chamaeleo zeylanicus was studied in Orissa, in captivity and in the wild. Captive specimens were housed in enclosures with ample vegetation, and maintained on an insect diet. The smallest female with functional ova was 375 mm in total body length. Mating occurred during the last week of August, and egg laying in October. The shape and size of the nest depended on the suitability of the ground. On soft fine sand the nest was an oblique hole, 22 cm in depth, 9 cm in diameter at the mouth. The eggs were 15-22.5 mm x 9-12 mm x 1.0-2.0 gm. There was indication of increase in size and weight of the eggs during incubation. Hatching occurred after eight months in the month of June, when small insects were available in large numbers. In three of the four cases reported, the female died within 1-42 days after egg laying. Females move less and are more territorial. Females are intolerant of close approach of other chameleons of either sex except of suitor males during a period of a few days when they are ready to mate. Mating is preceded by display by female and 'chase and escape' behaviour between the male and the female. Display by female and male (against other males) included assumption of deep green body colouration with dark spots and blotches, lateral flattening of the body, and hissing with open mouth.

Effects of high and low cast feed on the hatching and survival rate of freshwater prawn Macrobrachium rogenbergii larvae were observed. Three different treatments (T1, T2 and T3) were designed with three types of feeds as follows: T1, Saudi-Bangla Prawn feed 100%; T2,Saudi-Bangla prawn feed 50% + low cast feed 50%; T3, low cast feed 100%. The prawns were reared from February to May 2001 until they became mature enough to breed. The results showed that the average value of hatching rate was 90.14%, 89.69% and 89.29% and the average survival rate of larvae was 39.44%, 38.88% and 38.33% in Tl, T2 and T3 respectively. There were no significant differences (P>0.05) between hatching and survival rate of M. rogenbergii from different feeding trails. The price of Saudi-Bangla prawn feed was very high (Tk. 24/kg) than the local feed (Tk. 14/kg). So, use of local feed was recommended for M. rogenbergii brood rearing.

Effects of culture filtrate of Verticillium chlamydosporium were evaluated on mortality of larvae and hatching of eggs of Meloidogyne javanica. Mortality of M. javanica larvae was found to be directly proportional to concentrations of culture filtrate of V. chlamydosporium and duration of exposure. Maximum mortality of larvae (65.5%) was observed in 100% concentration of culture filtrate after 72 h followed by 80 % concentration which caused 53.25 % mortality. Similarly different dilutions of culture filtrate significantly inhibited hatching of M. javanica eggs. Larval emergence was, however, inversely proportional to filtrate concentrations. Significant lower hatching was observed in 100 % concentration.

Ostrich chick mortality was studied in 2522 chicks that were hatched artificially during the 1999/2000 breeding season. High levels of mortality were observed, with 1978 (78.4 %) of these chicks dying before 90 days after hatching. Atotal of 46.7 %(1177) of these chicks died before 28 days of age, and a further 30.7 %(801) died between 28 and 90 days post-hatching. Chick mortality to 28 days of age could not be conclusively related to sex, day of external pipping or breeder diet. Mortality rates were higher (P < 0.05) at the beginning and end of the breeding season than in the middle months. Differences in mortality levels of chicks incubated in different incubators could be related to the time of the breeding season during which the incubator was mostly used. The regression of chick mortality to 28 days of age on day-old chick mass followed a 2nd-degree polynomial. Chicks with day-old masses below 762.5 g were particularly at risk of dying before 28 days after hatching. Chicks h...

This study was conducted to determine the influence of eggshell thickness, albumen height, yolk height and haugh unit on hatching results. A total of 746 eggs, which were obtained and evaluated for egg quality parameters from 100 brown pure line hens of 42 weeks of age, were used. Eggs were collected from each hen for 12 days and individual incubation was carried out. Eggs were grouped based on quality parameters and evaluated accordingly. The findings suggested that hatchability, hatchability of fertile eggs, early, mid and late embryonic mortality did not differ in terms of haugh unit, albumen height, eggshell thickness and yolk height groups. However, early embryonic mortality was found different between the yolk height groups. No relationship was determined among albumen height, haugh unit, eggshell thickness and hatching results. There was no relation between yolk height and hatchability of fertile eggs, hatchability, mid and late embryonic mortalities but was a positive correl...

The effect of anthropogenic magnetic field on water ecosystems has been constantly growing as a result of an increasing number of underwater cables transferring electric current. Northern pike were subjected to a static magnetic field (emitted by DC cables) of 10 milliteslas (mT) during the embryonic phase and in the first six days post-hatching (DPH), in the period when larvae of this species in the natural environment are attached to artificial substrate. No statistically significant effect of a magnetic field was recorded on the hatching success (87.1% in the magnetic field and 83.3% in the control) or on larvae mortality (54.5% in magnetic field and 54.3% in control). The size of larvae at hatching (9.84 mm SL in a magnetic field and 9.86 mm SL in a control) and their growth rate during the first six days of life (0.52 mm·day-1 in a magnetic field and 0.53 mm·day-1 in a control) were also almost the same - no statistically significant differences. A significant effect of a magnetic field, however, was observed on the time of hatching (one day earlier in a magnetic field than in a control), yolk-sac size on 1 DPH (smaller in a magnetic field), and yolk-sac absorption time (faster in a magnetic field). Faster yolk-sac absorption time in a magnetic field was interpreted as an indication of increased metabolic rate. Even if some negative consequences may be expected as a result of shorter time until first feeding, the actual risk for increased Northern pike larvae mortality due to those factors seems to be negligible. Although it cannot be excluded that higher than 10 mT magnetic field values are hazardous for fish larvae, such values do not occur in the natural environment (e.g. along underwater cables).

Background: This study was undertaken to evaluate the major causes of mortality at different stages of incubation and their economic impact in response to sustainability challenges at the Rwandan National Hatchery.Methods: The study evaluated the fertility, hatchability and embryonic deaths in broiler-producing flocks (B series) and layer-producing flocks (L series) at Rubilizi, a state-owned hatchery in Kigali, Rwanda.Results: Mean fertility in the B series (94.23%) was not significantly different (P > 0.05) from that of the L series (93.24%). Mean hatchability in the B series (57.39%) was significantly (P 0.05).Conclusions: Low hatchability in the L series possibly resulted from the higher number of embryonic deaths and hatch debris and not from reduced fertility or cull chicks. Total chick losses during the study amounted to US$54 327.00. The hatchery was experiencing more losses in layers than in broilers as emanating from low hatchability of the layers. Further investigation...