Benefits of Courtship-Feeding for Rifleman (Acanthisitta Chloris) Parents

Behaviour ◽  
1989 ◽  
Vol 109 (3-4) ◽  
pp. 303-318 ◽  
Author(s):  
Greg Sherley
Keyword(s):  
Egg Laying ◽  
Early Season ◽  
Food Items ◽  
Total Food Intake ◽  
Energy Demands ◽  
Pair Bonds ◽  
Courtship Feeding ◽  
Total Food ◽  
First Clutch ◽  
Maintenance Requirements

Abstract1. Courtship-feeding was studied in riflemen (Acanthisitta chloris) in a population at Kaikoura, South Island, New Zealand between 1982 and 1984. The proportion of the food males collected which was donated to his mate was calculated and what proportion of the female's diet this represented. This information revealed that males made a significant early season contribution to parental care. 2. Allied information collected during the pre-lay and egg-laying periods included the time to form eggs, laying interval and clutch size. 3. Courtship-feeding in riflemen involved no ceremony. 4. Copulation attempts did not correspond with bouts courtship-feeding or the peak of courtship-feeding. 5. Pairs spent 91.2% of daylight hours in each other's company, which facilitated coursthip-feeding. 6. Food items delivered in courtship-feeding were significantly larger than those eaten by males or females while foraging for themselves, and larger food items were consistently offered throughout the pre-laying and egg-laying periods. 7. The peak in the volume of food delivered to the female occurred about 3.5 days after the first egg was laid. 8. Overall the male contributed 42% of the food he gathered to the female and this comprised 35% of her total food intake. 9. Females fed themselves enough food to meet maintenance requirements and the extra required for oogenesis was received from the male through courtship-feeding and any reserves stored by the female. 10. Riflemen laid eggs every 48 hours which probably reduced peak energy demands during oogenesis. 11. Courtship-feeding was not associated with second clutches which were significantly smaller than the first clutch laid and reared in a season. 12. Incubation occurred after the last egg was laid but was sometimes delayed. During the delay courtship-feeding continued until incubation started. 13. Courtship-feeding represents a significant early season investment by male riflemen in their offspring which probably allows time to rear two broods thereby improving both parents' productivity. Such early season investment might influence sexual selection towards stable, monogamous pair bonds.

Sexual dimorphism in size and plumage of the polyandrous Dotterel (Charadrius morinellus): sex roles and constraints on sexual selection

1988 ◽  
Vol 66 (6) ◽  
pp. 1334-1341
Author(s):  
John Atle Kålås
Keyword(s):  
Sexual Dimorphism ◽  
Wing Length ◽  
Pair Formation ◽  
Egg Laying ◽  
Published Data ◽  
Museum Specimens ◽  
Time Activity ◽  
Monogamous Species ◽  
First Clutch ◽  
Behaviour Data

Data on live birds and previously published data reveal that female Dotterel (Charadrius morinellus) were on average larger than males for all measurements. However, sexual dimorphism on the basis of size appears weaker than expected when Dotterel are compared with closely related monogamous species. Female museum specimens have less disrupted (brighter) plumage colours than males, and dimorphism in plumage is more pronounced than it is in size. A discriminant analysis based on plumage characters did not separate the sexes totally, however. Females moult earlier in the spring than males, but summer plumage is still not fully developed for all females by the first period of pair formation, suggesting that female plumage is most important in reproduction only after the first clutch is complete. No significant differences were evident in wing length and plumage colour between 1882–1917 and 1957–1982. Time–activity studies on the polyandrous Dotterel during the arrival, prelaying, and egg-laying periods showed small differences between the sexes in the amount of time devoted to agonistic and courtship behaviour. Data from prelaying periods showed no difference between the sexes as to who initiates bouts of courtship and agonistic behaviour. The behaviour of paired birds was highly synchronized. Three hypotheses on the slight sexual dimorphism in size and plumage of this polyandrous species are presented and discussed.

scholarly journals Blueberry, Early Season Control of Cranberry Fruitworm and Cherry Fruitworm, 1996

1997 ◽  
Vol 22 (1) ◽  
pp. 53-53
Author(s):  
John C. Wise
Keyword(s):  
Egg Laying ◽  
Early Season ◽  
Cranberry Fruitworm ◽  
Research Complex

Abstract Insecticides were applied to mature blueberry bushes at the Trevor Nichols Research Complex in Douglas, MI at a rate of 50 GPA with a FMC 1029 airblast sprayer. Treatment plots were arranged in a CRB design of two 44 ft long rows containing a total of 22 bushes, replicated 4 times. Funginex was applied separately to all treatments. Applications of materials were made on 10 Jun (1st egg laying, Bloom), 19 Jun (Petal Fall), 25 Jun (PF + 7 days), and 2 Jul (1C). Harvest fruit evaluations were made on 12 Jul by randomly picking 25 blueberry fruit clusters per replicate, or 100 clusters per treatment, and evaluating the fruit for CBFW and CFW injury.

Effect of adrenalectomy and corticosterone replacement on meal patterns of Zucker rats

1985 ◽  
Vol 249 (5) ◽  
pp. R584-R594 ◽  
Author(s):  
M. R. Freedman ◽  
T. W. Castonguay ◽  
J. S. Stern
Keyword(s):  
Weight Gain ◽  
Food Intake ◽  
Body Weight Gain ◽  
Zucker Rats ◽  
Meal Frequency ◽  
Light Cycle ◽  
Dark Cycle ◽  
Meal Patterns ◽  
Total Food Intake ◽  
Total Food

Male obese and lean Zucker rats were adrenalectomized (ADX) or sham-operated at 10 wk of age. Approximately 16 wk later, patterns of food intake were monitored by computer-interfaced top loading balances. Data were collected from ADX rats before, during, and after access to a corticosterone-supplemented saline solution (20 micrograms/ml). Although total food intake during the precorticosterone treatment period was not different between ADX and sham controls, ADX resulted in attenuation of light cycle food intake, primarily via decreased meal frequency. With steroid replacement, light cycle meal frequency and food intake increased. Despite comparable self-administered dose (20.33 +/- 0.89 vs. 17.05 +/- 1.2 mg corticosterone/period, obese vs. lean), obese ADX rats were more responsive to steroid than were lean ADX rats. This increased responsiveness was reflected by a 30% increase in food intake and 60% increase in body weight gain of obese ADX rats during replacement. Lean ADX rats exhibited no change in total food intake or weight gain with replacement. Further, during corticosterone treatment, obese ADX rats increased meal frequency, total food intake, and consumption of large meals (greater than or equal to 4 g) during the dark cycle. Significant postprandial correlations were found only in obese ADX rats, both with and without replacement during the dark cycle. These results suggest adrenal glucocorticoids have a minimal effect on food intake and meal patterns in lean Zucker rats but significantly alter intake and meal patterns in obese rats.

PREVIOUS DIETARY PROTEIN LEVEL AND SURVIVAL OF STARVING RATS IN THE COLD

1963 ◽  
Vol 41 (1) ◽  
pp. 171-178 ◽  
Author(s):  
John R. Beaton ◽  
T. Orme ◽  
A. Turner ◽  
J. Laufer
Keyword(s):  
Body Weight ◽  
Dietary Protein ◽  
Protein Level ◽  
Environmental Temperature ◽  
Body Weight Loss ◽  
Protein Diet ◽  
Dietary Protein Level ◽  
Total Food Intake ◽  
Total Food ◽  
Ad Libitum Feeding

The effect of the level of dietary protein (5%, 20%, 40% casein by weight) fed for 7 days in an environmental temperature of 22 °C, upon the survival of rats subsequently starved in an environmental temperature of 2 °C was studied. In these experiments ad libitum feeding, isocaloric feeding, and restricted feeding techniques were used, and the effects of thyroidectomy and thyroid feeding were investigated. In all cases, animals provided with the 5% protein diet survived for shorter periods than did those fed the 20% protein diet. In intact rats, but not in thyroidectomized rats, survival time appeared to be inversely related to rate of body weight loss in starvation. Differences in duration of survival among dietary groups are not explicable on the basis of differences in body weight, body composition, or total food intake prior to starvation. The results of experiments using thyroidectomized rats and thyroid feeding suggest that the effect of dietary protein level upon survival in subsequent starvation in the cold are not mediated through the thyroid gland.

scholarly journals Mate Attentiveness, Seasonal Timing of Breeding and Long-term Pair Bonding in the House Finch (Carpodacus mexicanus)

Behaviour ◽  
2004 ◽  
Vol 141 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Geoffrey Hill ◽  
Kevin McGraw
Keyword(s):  
Pair Bond ◽  
Egg Laying ◽  
Carpodacus Mexicanus ◽  
Timing Of Breeding ◽  
Pair Bonding ◽  
House Finches ◽  
Breeding Date ◽  
Pair Bonds ◽  
Term Pair

AbstractIn seasonally breeding birds, natural selection favors individuals that begin breeding earlier in a year because they produce more or higher quality offspring than those that begin breeding later. Among the factors that influence the timing of breeding, which include the age, health, competitive ability, or mate quality of individuals, is the longevity of the pair bond, with birds that remain mated across years initiating breeding earlier in the season than newly formed pairs. The behavioural interactions between pair members that may facilitate long-term pair bonding and early breeding onset have infrequently been studied, however. Here we report the relationship between male-female affiliative behaviour, pair-bond duration, and breeding date in house finches (Carpodacus mexicanus), a short-lived, socially monogamous passerine species in which the duration of pair bonds is highly variable within and among seasons. Finches that initiated breeding earliest in the season were those that had bred with one another in previous years. Early breeding males from returning pairs maintained significantly closer contact with their mate during the first egg-laying period of the year than did males from late-breeding, newly formed pairs. Similarly, early-breeding females from returning pairs followed their mate more closely in nest-vicinity flights during the fertile period than females from late-breeding, newly formed pairs. These results suggest that attributes of and interactions between both pair members may help to maintain stable breeding pairs and influence the timing of breeding in seasonally nesting, short-lived songbirds. Rather than advertising for or seeking extra-pair fertilization opportunities, high-quality pairs of finches may invest heavily in their mate to secure the pair bond and ensure high intrapair reproductive success.

scholarly journals STUDIES ON THE TOTAL BILE

1924 ◽  
Vol 40 (1) ◽  
pp. 25-42 ◽  
Author(s):  
Philip D. McMaster
Keyword(s):  
Food Intake ◽  
Gall Bladder ◽  
Total Food Intake ◽  
Total Food ◽  
Additional Amount ◽  
Ordinary Diet

The development of a method for the collection of total bile from dogs in a sterile state and uninfluenced by the gall bladder, day after day for weeks, has rendered possible an accurate study of the influence of diet upon the cholesterol output of the secretion. When a diet rich in cholesterol is given the amount of the substance in the bile greatly increases. Not only this but the concentration per cc. is, in almost every instance, greater. An increase in the total food intake, by the addition to the ordinary ration of a bone mash diet containing only a slight additional amount of cholesterol (200 mg.) produces a similar, though lesser, increase. In the fasting dog, the cholesterol yield is greatly cut down. The increase in the cholesterol after food rich in the substance does not depend on the cholagogue action of this latter, though it is true that the concentration of cholesterol in the bile usually increases with the bile volume. Though fasting cuts down the cholesterol of bile, the concentration of the substance per cc. is greatly increased. On an ordinary diet the yield of it fluctuates abruptly and considerably from day to day. In general the rule holds that an animal eating largely puts out not only much more bile but much more cholesterol. The relation between bile quantity and cholesterol yield is anything but a fixed one, however. The cholesterol yield of the bile does not parallel that of bilirubin. The pigment output from day to day remains relatively constant as compared with that of cholesterol.

The food intake and growth of Australian feral cross Angora kids when fed whole grain barley-lupins diets with three levels of roughage intake

1984 ◽  
Vol 24 (124) ◽  
pp. 77 ◽  
Author(s):  
BA McGregor
Keyword(s):  
Food Intake ◽  
Crude Protein ◽  
Dry Matter ◽  
Barley Grain ◽  
Whole Grain ◽  
Total Food Intake ◽  
Total Food ◽  
Ad Libitum ◽  
Ad Libitum Feeding ◽  
Basal Ration

Kids six months old and of mean liveweight 22 kg were offered a basal ration of barley and lupins (crude protein 15 .4%) supplemented with three levels of chopped hay (0, 13% of total intake and ad libitum). Supplementation of the basal ration with 13% hay increased total dry matter intake from 479 to 753 g/d (P< 0.001) and liveweight gain from 10 to 54 g/d (P<0 .01). Non-significant increases in total food intake and liveweight gains were achieved by supplementing with ad libitum hay; kids fed ad libitum hay actually consumed 26.9% of their diet as hay. They were then offered various mixtures of barley, oats and lupins with 13% chopped hay at near ad libitum feeding. Differences in intake or growth were not significant at P= 0.05 with kids growing at 74, 65 and 101 g/d for those fed barley, oats and lupins respectively. Results indicate that highest food intake was obtained when 13% chopped hay was added to whole barley grain rations.

Diet selection in pigs: choices made by growing pigs given foods of different protein concentrations

1990 ◽  
Vol 51 (1) ◽  
pp. 189-199 ◽  
Author(s):  
I. Kyriazakis ◽  
G. C. Emmans ◽  
C. T. Whittemore
Keyword(s):  
Growth Rate ◽  
Food Intake ◽  
Protein Concentration ◽  
Live Weight ◽  
Diet Selection ◽  
Growing Pigs ◽  
Growth Potential ◽  
Feeding Method ◽  
Total Food Intake ◽  
Total Food

ABSTRACTTo test the proposition that growing pigs, when given a choice between two foods, are able to select a diet that meets their requirements, and to investigate the rules of diet selection, four foods (L, A, B and H) with similar energy yields, but different concentrations of crude protein (CP) (125, 174, 213 and 267 g CP per kg fresh food respectively) were formulated. The four foods were offeredad libitumeither singly, or as a two-way choice using all the six possible pairs, to 40 individually caged pigs from 12 to 30 kg live weight. On the single foods the rate of food intake fell from 1001 to 971 to 961 to 868 (s.e.d. 40) g/day (F < 0·05) as the protein concentration of the foods increased from L to H; the growth rate followed an opposite trend (492, 627, 743 and 693 (s.e.d. 31) g/day respectively;P< 0·01). When the pigs had to select between two foods limiting in protein (L and A) the less limiting one was preferred (710 (s.e. 200) g A per kg total food intake; the protein concentration of the selected diet was 160 (s.e. 10) g CP per kg). On the choice between B and H (a choice between a food with protein concentration close to requirements and a food with protein excess) the lower food was markedly preferred (928 (s.e. 4) g B per kg total food intake; the protein concentration of the selected diet was 218 (s.e. 1) g CP per kg). When the animals were given a choice between two foods, a combination of which was non-limiting (pairs LB, LH, AB and AH), the protein concentrations of the selected diets were not different between treatments (208, 204, 202 and 205 (s.e.d. 13) g CP per kg respectively) and they also declined systematically with time and weight. The growth rate of the animals on these pairs were 752, 768, 769 and 763 (s.e.d. 54) g/day (P > 0·05), which were not significantly different from the highest growth rate achieved on a single food. The results suggest that pigs, when given a choice between a suitable pair of foods, are able to choose a balanced diet and to change its composition to reflect their changing requirements. The choice-feeding method may well be useful as an effective and economic way of estimating and meeting requirements, and of measuring the growth potential of pigs.

Quantitative aspects of feeding of chaetognaths in the eastern Mediterranean pelagic waters

2003 ◽  
Vol 83 (3) ◽  
pp. 559-569 ◽  
Author(s):  
George Kehayias
Keyword(s):  
Eastern Mediterranean ◽  
Standing Stock ◽  
Gut Content Analysis ◽  
Ionian Sea ◽  
Gut Content ◽  
Sampling Area ◽  
Food Items ◽  
Total Food ◽  
The Mean ◽  
Pelagic Area

The diet of all chaetognath species found in a broad pelagic area of the eastern Mediterranean was investigated through gut content analysis. Eight chaetognath species were recovered from four depth intervals between 0 to 300 m in the Ionian, Cretan and Rhodes Seas and in the Cretan Passage. The mean food containing ratio (FCR) value for all chaetognaths combined was 0·048. Copepods comprised nearly 65% of the total food items consumed. The epipelagic species Sagitta enflata, Sagitta serratodentata atlantica, Sagitta bipunctata and Sagitta minima fed mainly in the 0 to 50 m surface layer, while the mesopelagic species Sagitta lyra, Sagitta decipiens, Sagitta hexaptera and Krohnitta subtilis fed in deeper layers. Sagitta s. atlantica showed the highest mean FCR in the integrated water column (0 to 300 m) of the whole sampling area. The estimated impact of chaetognath predation on copepod communities ranged from 0·3 to 7·8% of the copepod standing stock, and was higher in the Ionian Sea and the Cretan Passage than in the Cretan and Rhodes Seas. Sagitta s. atlantica, S. lyra, and S. decipiens had the most important predation impact among the eight chaetognath species found in the 0 to 50 m, 50 to 100 m and 100 to 300 m depth layers respectively.

Extra-Pair Copulations in the Red-Billed Gull: Females With High-Quality, Attentive Males Resist

Behaviour ◽  
1994 ◽  
Vol 128 (1-2) ◽  
pp. 41-64 ◽  
Author(s):  
J.A. Mills
Keyword(s):  
Mating System ◽  
Reproductive Investment ◽  
Pair Bond ◽  
Feeding Rates ◽  
High Quality ◽  
Fertile Period ◽  
Pair Bonds ◽  
Courtship Feeding ◽  
Term Pair ◽  
Strange Male

AbstractExtra-pair copulation (EPC) and within-pair copulation (WPC) behaviour of red-billed gulls (Larus novaehollandiae scopulinus) was observed in a breeding colony at Kaikoura Peninsula, New Zealand. Twenty-five females and 19 individually colour-marked males were monitored for six hours per day for twenty days from 20 September to 30 October 1973. Extra-pair copulation attempts were common, amounting to 21% of all copulation attempts, but less than 3% were successful during the fertile period of the female. Ten percent of EPCs were on males. Within-pair mountings were eight times more likely to end in cloacal contact than EPCs. Within-pair and EPC attempts occurred throughout the day, but the frequency of WPC attempts increased markedly towards evening, possibly as an adaptation to ensure last-male sperm precedence. Approximately 80% of females, but only 32% of males, were involved in EPC attempts. Mounting within and between pairs increased in frequency about 15 days prior to laying of the first cgg. Within-pair copulation attempts ceased abruptly after the first egg was laid, but EPC attempts on the female continued well into incubation and amounted to 11% of the total EPC attempts. Seventy-five percent of EPC attempts occurred in the fertile period of the recipient female. Approximately 75% of the EPC attempts by males occurred over a nine-day period; six days prior to and two days after its mate had laid the first egg. No EPC attempts were recorded for males more than seven days after its mate commenced laying. The female had control as to whether the copulation attempt would be successful. In WPC attempts the female ended the mount on 72% of the occasions, whereas all EPC attempts were ended by the female. Approximately 91% of within-pair mountings followed some form of courtship feeding display, and in the remaining 9% the male mounted without courtship preliminaries. In contrast, 97% of extra-pair mountings occurred in the absence of courtship displays. On the two instances where preliminaries occurred, mounting followed courtship feeding solicitation by the female towards the strange male. Potentially high quality females which were being well provisioned in courtship feeding by their mates were at greater risk from EPCs because they were able to spend more time at the nest site than less well provisioned females. Females which were well fed during courtship feeding resisted all EPC attempts and retained their partner the next breeding season. Poorly courtship fed females divorced the next season. One such female solicited an EPC four days prior to the laying of her first egg. There was no evidence to suggest that males performing EPCs were at risk from being cuckolded and the male partners of females experiencing high numbers of EPCs did not respond to the risk by having more WPCs or having more genital contacts per hour. It is considered that EPCs were not a major feature of the mating system for the majority of red-billed gulls. The advantages of EPCs were greater for females than for males and the results support the genetic quality hypothesis. Theoretically if males wanted to maximise their fitness they should attempt EPC's on females nesting earlier than themselves, but this only happened on 17% of the EPC attempts. The high number of WPCs, the increase in frequency of copulations in the evening and high courtship feeding rates are measures that help to ensure paternity of the true mate. It is hypothesized that in species like the red-billed gull which have long-term pair-bonds and invest considerable time and energy in courtship feeding and parental care during incubation and chick rearing it would be more advantageous to strengthen the pair-bond than to philander to increase production. In a mating system such as this, philandering would jeopardize the current reproductive investment and future reproduction because those which change partners are less productive than those which retain their partners and for those which divorce the probability of breeding the next season is lower than for those which retain pair-bonds (MILLS, unpub. data). More successful breeding occurs if the pair-bond has been established for more than one year (MILLS, unpub. data). Thus, in this mating system the ''attentive prosper''.

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