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1.
The three-spot swimming crab Ovalipes punctatus is commonly found in surf zones off sandy beaches in Algoa Bay. It is exclusively marine and occurs down to a depth of 38 m. Large crabs were found close inshore while smaller crabs were predominantly found in deeper water, suggesting that settlement mainly occurs offshore in water 25 – 38 m deep. Gravid females were found closer inshore in shallow water. The zoeae could not tolerate high temperatures (>27,5 °C) or low salinities (<15‰). The optimal temperatures and salinities for survival of the zoeae were 15–22 °C and 34–35‰ respectively.  相似文献   

2.
《African Zoology》2013,48(3):249-257
Understanding fish movement patterns and migrations is important for fisheries management as well as the identification and conservation of critical habitats. Data collected by the Oceanographic Research Institute's Cooperative Fish Tagging Project (ORI-CFTP) were used to describe the large-scale movement patterns of Lichia amia along the South African coastline. A total of 10 762 L. amia were tagged between 1984 and 2012, of which 744 (7%) were recaptured. Most tagging effort, mainly on juvenile and subadult individuals, took place along the south-eastern (i.e. Eastern Cape) and south-western (i.e. Western Cape) regions of the country during summer. Conversely, more L. amia were tagged and recaptured (mostly adults) during winter and spring (July to November) along the north-east coast (i.e. KwaZulu-Natal). Movements (dispersal distance in kilometres) by juveniles were restricted and largely confined to estuaries within the south-eastern and south-western regions of the country. There was a significant effect of fish size on distance moved (ANOVA: p<0.001), with evidence of a distinct seasonal (winter) longshore migration by adults to KwaZulu-Natal. The consequences of juvenile residency in estuarine habitats and high recapture rate of adults during a directed, seasonal spawning migration are discussed in light of improving current fisheries management.  相似文献   

3.
The intermandibular width (IMW) was measured on 3042 Thoroughbreds ranging in age from 12 to 319 months and subsequently compared to their racing performance. IMW had a near normal distribution for both males and females and mean IMW was similar (P>.05) between both groups as yearlings and two-year-olds. However, after 36.5 months the mean IMW of males (9.63 cm) was greater (P<.002) than females (9.29 cm) and continued to become more pronounced with age. Males had an IMW growth rate of 9.1% compared to a 5% growth rate for females. For both males and females, grown IMW (GIMW) was weakly correlated (r−.08, P=.01) to grown height (GHT). Male GIMW had a small inverse relationship (r=−.062, P=.0412) to highest racing performance (HP) and a somewhat stronger inverse relationship (r=−.130, P=.0001) to highest racing distance (HD). For females, the correlation of GIMW with HP was essentially zero, but again a negative relationship (r-−.076, P=.0147) was found between GIMW and HD. Surprisingly, when individual GHT of males and females was divided by individual GIMW, there was a greater (P<.02) percentage of graded stakes winners in the groups with the highest (narrower IMW) ratio. Similarly, horses with the highest ratio were more (P<.0001) successful at racing distances over eight furlongs while horses with lower ratios (wider IMW) were more (P<.05) successful at sprint distances. The reason(s) for these findings remain the focus of further research. However, IMW may well be more reflective of individual body shape, than anything else, since narrower bodied horses, in general, tend to be best suited for distance racing, whereas wider bodied individuals tend to be best suited for sprint racing. Although IMW was not a useful indicator of Thoroughbred racing potential, the former claim that horses (particularly tall individuals) with ‘narrow’ IMW are at a racing performance disadvantage was unfounded.  相似文献   

4.
The third interosseous muscle (suspensory ligament, TIOM) is composed of connective tissue (CT) with a variable proportion of muscle (MT) and adipose tissue (AT). The aim of our study is to quantify the CT, MT and AT within the body and the branches of right thoracic and pelvic limbs TIOM in sound horses to determine whether there are differences in CT, MT and AT between age, sex, limbs and levels. Right limbs from 11 sound horses were collected. Samples from 6 levels of the TIOM were embedded in paraffin or in Tissue‐Tek®. Most of the paraffin sections were shredded. Using the cryosection, some artefacts appeared. Cryoprotection was carried out, which produced the best results. Hematoxylin–phloxine–saffron and Hematoxylin–eosin gave a good contrast of colours between the tissues observed allowing the use of an image analysis programme to calculate percentage of each tissue within the TIOM. The percentage of MT and AT decreased significantly (P < 0.0001), whereas the percentage of CT increased significantly (P < 0.0001) with age and when descending from the proximal to the distal level of the TIOM. The percentage of MT was significantly higher (P < 0.0001) in females than males, while the percentage of CT was significantly higher (P < 0.0001) in males than females. The percentage of AT was significantly higher (P = 0.0278) in pelvic limbs than in thoracic limbs. These results confirm the variation in tissue composition within the TIOM of sound horses.  相似文献   

5.
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6.
Growth hormone (GH) profiles were measured during a 60-hour period in four release was not affected by feeding when measured at 2, 4 and 8 hr before and after castrated male and five female, 20-week-old Yorkshire pigs. During this period, GH feeding time. A photoperiod of 12 hr light and 12 hr darkness produced a decrease (P<.05) in baseline mean GH levels from 4.0 to 3.5 ng/ml during periods of darkness. This effect was observed in both genders. Females and castrated males exhibited (P>.05) similar baseline GH levels and identical numbers of GH peaks during feeding and photoperiod studies. However, during these periods, the amplitude of the GH peaks and areas under the GH curves were greater (P<.05) in females. These results indicate that: 1) feeding did not influence GH secretion; 2) darkness produced a decrease in the baseline GH levels in both sexes; and 3) females secreted more GH than castrated males of the same age.  相似文献   

7.
Upright and pendulous combs commonly exist in most single‐comb chicken breeds. Here, the phenotypic characteristics of upright and pendulous combs in chickens and association with growth rate and egg production were analyzed. Phenotypic frequencies of upright and pendulous comb were investigated in five chicken breeds; the phenotypic frequencies of complete pendulous comb (CPC) and partial pendulous comb (PPC) ranged from 10.1% to 29.0% and 21.8% to 65.3%, respectively. CPC hens produced more eggs than PPC hens (P < 0.05) in Nongda‐3, Huainan and Wenchang breeds. In Huainan breed, CPC males were heavier than PPC males at 12 and 16 weeks of age, while CPC females were heavier at 24 weeks of age. PPC and CPC chickens have greater (P < 0.05) comb length, comb height and comb index than upright comb (UC) chickens. There was no significant difference in comb phenotypic frequency distribution between the offspring from UC(♂) × CPC(♀) and CPC(♂) × UC(♀); however, it differed (χ² = 45.12, P < 0.01) between offspring from UC(♂) × UC(♀) and CPC(♂) × CPC(♀). These results suggested that the comb phenotype does not appear to be Z‐linked; the effective loci influencing the trait could be estimated in a further study.  相似文献   

8.
ABSTRACT

1. The potential growth of feathers and feather-free body and their chemical components was measured in two commercial broiler strains.

2. A total of 200 chicks of each sex x strain were fed adequate amounts of dietary protein using a four-phase feeding programme. Ten birds per genotype were sampled at 14, 28, 42, 56, 70, 84, 98 and 112 d of age. They were weighed before and after being dry-plucked to determine the weight of feathers, and the feather-free body was then minced and analysed for water, protein and lipid.

3. Body weights and chemical composition of males of the two strains were similar throughout the trial. Females of the two strains differed only in their body lipid contents, with mature Cobb females being higher than Ross (1371 vs. 1210 g).

4. Mature body weights of males and females from both strains averaged 8420 g and 6650 g; mature body protein weights averaged 1555 g and 1030 g; and mature body lipid contents averaged 908 and 1290 g, respectively.

5. Rates of maturing per day of body weights of males and females of both strains averaged 0.0385 and 0.0368; feather-free body protein was 0.0316 and 0.0348 and body lipid was 0.0503 and 0.0375, respectively. The rates for body lipid differed between Cobb and Ross females (0.0352 vs. 0.0397/d). Separate equations were required for males and females to describe the allometric relationship between lipid and protein in the feather-free body.

6. The rate of maturing of feathers in females was higher than in males (0.0526 vs. 0398/d) and the mature weight was lower (205 vs. 266 g), respectively. Mature body weights of broilers in this trial were considerably higher than those measured using the same protocol 24 years ago, whereas rates of maturing remained the same.  相似文献   

9.
A longitudinal demonstration project was carried out in 2005/2006 for thirteen months to determine the effectiveness of a strategic community-based worm control (CBWC) programme in the control of gastrointestinal (GI) nematodes and Fasciola gigantica in cattle. Two villages namely, a CBWC village (Ilula-Masukanzi) and a village without CBWC (Kilolo-Luganga) were randomly selected in Kilolo district, Iringa region of Tanzania. Animals in both villages were under the traditional management system and used the village communal grazing area. At the village with CBWC, 60 zebu cattle (6–18 months old) from 10 farms in the village were selected and ear tagged for monthly sampling and weghing. A strategic CBWC programme was instituted whereby all animals in the village (tagged and non-tagged) were treated with albendazole 10% drench at 10 mg/kg four times a year e.g. middle of the rainy season (February), end of the rainy season (May), middle of the dry season (September) and late dry/early rainy season (December). In the village without CBWC, 68 zebu cattle (6–18 months old) from 11 farms in the village were selected and tagged for monthly sampling and weighing. Farmers in the village without CBWC were allowed to continue with their normal management practices including anthelmintic treatments. Faecal and blood samples from tagged animals and pasture samples from communal grazing areas were collected on monthly basis for 13 months. Results showed that strategic CBWC programme was highly effective in reducing faecal egg counts (FEC) and the proportion of animals passing Fasciola eggs in faeces. The strategic CBWC significantly reduced FEC of animals by an average of 60% compared to animals at the village without CBWC (P < 0.01). Four strategic CBWC treatments per year significantly reduced the proportion of animals passing Fasciola eggs in faeces by an average of 82.5% compared to animals at the village without CBWC (P < 0.05). From commencement to the end of the trial, animals at the village with CBWC significantly outgained animals at the village without CBWC by an average of 13.9 kg per year (P < .05). It is concluded that strategic CBWC programme was highly effective in reducing FEC, reducing the proportion of animals passing Fasciola eggs in faeces and improved weight gain in animals.  相似文献   

10.
Eighteen cattle (six Bonsmara males, seven Simmanteler x Beefmaster males and five Simmanteler x Beefmaster females) were assigned to three diets containing 0% (Control), 10% and 20% Macadamia oil cake to evaluate the effects of different levels of Macadamia oilcake (MOC) on feed intake, growth performance and carcass characteristics of feedlot cattle. Differences in average feed intake were not significant (P > 0.05). Average daily gains on the 0% and 20% MOC diets were not significantly different (P < 0.05) but were significantly higher than the average gain on 10% MOC (P < 0.05). The inclusion of 20% MOC increased feed conversion ratio significantly (P < 0.05) compared with the other two treatments. The control group had significantly heavier warm carcasses than the 10% and 20% MOC groups and the 20% MOC group had significantly heavier carcasses than the 10% MOC group. The inclusion of MOC did not significantly affect the dressing percentage and conformation scores of the animals (P > 0.05). There were no condemned livers, suggesting that either there were no toxic factors in the feed or, even if present, were probably inactive in the liver.  相似文献   

11.
Effects of the opiate agonist, morphine, and antagonist, naloxone, on LH release, courtship behavior and ejaculation frequency of mature, sexually active or sexually inactive rams were investigated. Plasma LH concentrations were monitored from blood samples collected every 15 min for 10 hr (0800 to 1800 hr) from eight rams that were isolated from or in contact with estrous females. Plasma LH concentration was higher (P<.05) in sexually active rams exposed to receptive females compared with hormone concentration of rams isolated from ewes. Intravenous infusion of morphine sulphate (1 mg/kg) into rams 4 and 6 hr after exposure to ewes reduced (P<.05) plasma LH concentration as compared to rams given saline. Morphine did not affect (P>.05) courtship behavior (investigatory sniff, mount attempt, foreleg kick, flehmen, vocalization) but diminished (P<.05) number of ejaculations. In another trial, LH concentrations were higher (P<.05) in seven sexually active rams given naloxone iv or when given to three rams through an intracerebroventricular cannula (icv) as compared to LH response of sexually inactive rams. LH did not differ (P>.05) in seven sexually inactive rams before or after administration of naloxone. Investigatory sniffs by sexually active rams were increased (P<.03) after treatment with the opiate antagonist. Four of the seven sexually active rams had more ejaculations after naloxone compared with the pretreatment period, but mean ejaculation frequency after treatment did not differ (P=.31). Naloxone did not stimulate courtship behavior of sexually inactive males. These data suggest that the effect of opiates on sexual behavior and LH secretion depends upon the inherent level of sexual activity among rams.  相似文献   

12.
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13.
Fish eggs, thought to be those of the liparid fish, Careproctus griseldea, were found In the gill chambers of several specimens of the stone crab, Lithodes tropicalls, caught In deep-water (-600 m) oil the South West African/Namibian coast (-24°46/S/13°28'E). The size class and quantity of crabs involved in this symbiotic relationship are discussed and some observations are made as to the diameter, number and maturity of the fish eggs removed from the crabs.  相似文献   

14.
Airag, (Fermented horse milk) is a traditional milk product in Mongolia. Herders separate foals from their dams and tie them at a milking site during the daytime to produce airag. To evaluate the effects of horse management on the movement of dams, we tracked three dams in a herd in camp 1 during summer and camp 2 during autumn of 2013 and analyzed their movements during the milking (daytime) and non‐milking (nighttime) periods in an area famous for its high‐quality airag. Dams were gathered every 1.7 ± 0.0 h between 07.46 and 15.47 hours at the milking sites and milked 4.6 ± 0.2 times/day during the study period (86 days). Daily cumulative and maximum linear distances from the milking sites were longer (P < 0.01) during the non‐milking period than during the milking period. Daily home ranges were 91 and 26 times greater during the non‐milking period (P < 0.001) in camps 1 and 2, respectively. The greater range during the non‐milking period would reflect the spatial distributions of water, salt and forage. The dams initially used similar areas and gradually shifted their daily home ranges after several days. This shift suggests that the dams grazed farther afield as forage availability declined around the milking site. For better airag production and sustainable pasture use, our results provide insights useful for evaluating the effects of milking management on vegetation and soil in those pastures, for selecting the appropriate milking times and frequency, and for choosing the right timing to shift milking sites.  相似文献   

15.
The effects of electrolytes and transportation on lamb, pig, and calf production and behavior traits were evaluated in three twice-replicated trials. In all trials, animals were randomly allotted to three treatment groups stratified by sex, weight, and breed: 1) not transported, water (CW); 2) transported, electrolyte (TE); and 3) transported, water (TW). Comparisons of CW vs TW resulted in the determination of the effects of transportation when water was used; comparisons of TE vs TW allowed the determination of the effects of electrolyte use in transported animals. Each trial consisted of two transportation days 1 wk apart (transports 1 and 2). Each transportation day consisted of a 4-h rest period between two separate 80-km transports. Seventy-two Dorset lambs (average 105 d; 51 ewes and 21 wethers), 72 Yorkshire weaned pigs (average 51 d; 15 barrows and 57 gilts), and 39 Angus x Simmental cross heifers (average 265 d) were used. In the lamb trial, for transports 1 and 2, weight loss was not different (P>0.05) for TE vs TW; CW lost less (P<0.01) weight than did TW. Average consumption per animal in the TE treatment group was 2.00 kg water or electrolyte solution, and the average per animal consumptions in the TW and CW treatment groups were 2.06 and 2.67 kg water, respectively. In the pig trial, for transports 1 and 2, weight loss was less (P<0.01) for TE than for TW. Average consumption in the TE treatment group was 6.38 kg water or electrolyte solution, and the averages for the TW and CW treatment groups were 4.20 and 5.71 kg water, respectively. In the heifer trial, for transports 1 and 2, weight loss was not different (P>0.05) for TE vs TW; CW lost less (P<0.01) weight than TW. The average animal in the TE treatment group consumed 9.06 kg water or electrolyte solution; the average per animal consumptions in the TW and CW treatment groups were 9.87 and 10.45 kg water, respectively. There were no differences in the behaviors or activities (agonistic, movement, lying down, or loss of balance) of the groups during transport. Administration of electrolytes prior to and during a rest period between transportations appeared to decrease weight loss and increase fluid consumption. This was more pronounced in monogastrics than in ruminants.  相似文献   

16.
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17.
1. The Gompertz equation was used to described the growth of the European quail (Coturnix coturnix) from hatching until 107 d of age.

2. Differences (P < 0.05) in growth existed between sexes. Mature mass values of 148.0 ±3.00 and 191.9 ±5.35 g respectively were found for males and females. Males reached maximum growth at 13.4 ± 0.33 d while a value of 16.4 ± 0.46 d was found for females.

3. A plateau in daily food intake was reached when the time of mature mass was approached.  相似文献   


18.
We determined for the first time the reproductive biology of Piabina argentea through macroscopic and microscopic analysis of ovaries and evaluated the morphological changes in hepatocytes. Two hundred and 46 specimens were collected, 204 females and 42 males, between March 2014 and February 2015. Biometrics data were obtained. From females, gonad and liver samples were conducted to histological, histochemical and immunohistochemical techniques. Mature ovaries were used to determine absolute and relative fecundity. Total length and body weight values indicated that females were larger than males. The estimated weight–length ratio showed negative allometric growth. The absolute fecundity average was 171.83 ± 59.89 oocytes per ovary. In addition, females spawning capable and regressing stages were found throughout the sampling period and the presence of all oocyte types in regressing stage ovaries indicated asynchronous oocyte development and multiple spawning. From regenerating to spawning capable stage the oocytes accumulated yolk in cytoplasm became bigger. While in the liver hepatocytes with a larger cell area during regenerating stage and proliferative activity in the spawning capable stage were observed. Thus, our results indicate that P. argentea had an opportunistic reproductive strategy and cyclic morphological changes of hepatocytes occurred during the oogenesis.  相似文献   

19.
Abstract

Unusual short-term associations provide insight into the long-term development or modification of parasitism. A superinfestation of a trap-held crevalle jack Caranx hippos by juvenile cymothoid isopods Cymothoa oestrum suggested loss of the mechanism controlling numbers of isopods on a host, and overcrowding on the host overcame this isopod's strict site specificity. Crabs (Decapoda) have not been reported as parasites of fishes, but unidentified crab zoeae superinfested the gills of a trap-held gray angelfish Pomacanthus arcuatus. Adult burrowing crabs Raninoides lamarcki invaded the gills of trap-held gray snapper Lutjanus griseus; this suggested how a relatively large crustacean could become an opercular chamber parasite and how wound feeding could occur. An apparent prey-to-predator transfer of the cymothoid isopod Anilocra acuta to a free-swimming king mackerel Scomberomorus cavalla also represented a move from an external to a pharyngeal-attachment position in this site-specific isopod. Trap confinement may have protected the infestations of juvenile C. oestrum and crab zoeae from organisms that serve as cleaners. New associations are usually begun by immature stages, but may also be initiated by adult crustaceans, as in the cases of A. acuta and R. lamarcki. The ability of crustaceans to survive, adapt, and be observed makes them excellent subjects for use in discerning complex parasitological processes.  相似文献   

20.
Sera from 497 sheep and 555 goats collected in a cross sectional study from different geographical locations in north-eastern Tanzania were examined for antibodies to Ehrlichia ruminantium using MAP 1-B ELISA technique. E. ruminantium antibodies were found in 68.6% (341/497) of sheep and 64.7% (359/555) of goats. Overall seroprevalence was 66.5% (700/1052). Infection rates were higher in sheep than goats (P < 0.05), in pastoral than in agro-pastoral production systems (P < 0.05) and in female sheep than males (P < 0.05). (131/143) 91.6% of the farms/flocks tested revealed sero-positive animals. E.ruminantium infections were found in all the geographical villages and districts tested. The infection rates per administrative district varied from 36.4% (Muheza) to 90% (Mkinga) in goats and from 11.9% (Muheza) to 94.6% (Mkinga) in sheep. The results shows E. ruminantium infection was prevalent and widely but unevenly distributed throughout the eight districts under study. These findings should be taken into consideration when future disease control and livestock upgrading programs are implemented.  相似文献   

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