Feeding motivation on the incidence of floor eggs and extraneously calcified eggs laid by broiler breeder hens

1. Commercial broiler breeder hens lay many eggs on the floor rather than in nest boxes provided. A study was conducted to determine whether feeding feed-restricted broiler breeder hens during the sitting phase of nesting results in a higher incidence of floor eggs and/or retained eggs. 2. Sixty broiler breeder females (Ross 308) were randomly assigned to 6 deep litter pens containing 10 nest-boxes. At 35 weeks of age and for 9 weeks, feed was distributed to all pens at lights-on every second day (fed normally, FN). On alternate days (feeding delay, FD), feed was distributed when 2-3 hens/pen were sitting in a nest box. Behaviour was sampled at 41 weeks of age, for 26 d. Eggs and egg location data were collected daily, and eggs were scored for extra-cuticular calcium. 3. Of 81 instances in which the hen was sitting firmly in a nest box at the time of feeding, on 80 instances the hen left the nest-box to feed, and on one instance the hen laid her egg then exited to the feeder. Of these 80 instances, on 58 occasions the hen returned to a nest-box to lay her egg; on 12 the hen returned to the nest-box but laid no egg; on 7 the hen did not return to the nest box and laid no egg; and on three the hen laid her egg on the floor. 4. Mean floor egg percentage was 13·3 ± 3·2% on FN and 13·3 ± 4·7% on FD days; these did not differ significantly. 5. The mean extra-cuticular calcium score over all pens was 0·9 ± 0·06 on FN days and 1·2 ± 0·06 on FD days; these differed significantly. 6. In conclusion, feeding broiler breeder hens during nesting results in a conflict between feeding and nesting motivation and higher numbers of extraneously calcified eggs, but does not result in a significant increase in floor eggs even though nesting hens will leave the nest box for food.     

减少肉种鸡场窝外蛋的方法

窝外蛋是许多肉种鸡场都可见到的问题,仅靠集蛋是无法得到解决的,其解决需要在饲养管理方式上作出改变。在理想生产条件下,窝外蛋有可能降低至1%以内。     

Dietary rapeseed meal and the incidence of tainted eggs

1. Incorporating 0, 3, 6 or 9% rapeseed meal in the diet of brown‐egg laying birds for 28 d resulted in the production of 0, 1.2, 19.3 and 20.9% tainted eggs respectively, the first tainted eggs being laid on the fifth day.

2. During the second and third weeks the incidence of tainted eggs exceeded 20% but fell to 11.4% during the final week.

3. Omission of the rapeseed meal from the diets halted the production of tainted eggs.

4. Neither egg production nor the health of the birds was adversely affected by the treatments.

5. The taint was described as “ fishy ” or “ crabby ” and was distinctive, but the source was not identified.     

Whitening of brown shelled eggs: Individual variation and relationships with age,fearfulness, oviposition interval and stress

1. Fearfulness, shell colour, incidence and degree of shell whitening and the interval between ovipositions were studied in two populations of 30 brown egg laying hens with family histories of a low or a high incidence of egg shell whitening.

2. Hens of the population with the high incidence of whitening appeared to be more fearful than hens of the population with the low incidence of whitening.

3. Brown colouration of the egg shell and the incidence and degree of shell whitening declined as the hens aged.

4. Brown colouration and egg shell whitening were most pronounced on the blunt ends of the eggs.

5. A large part of the variation in egg shell whitening was attributable to the individual (hen) component of variance.

6. Differences in egg shell whitening, between the two populations, were detectable throughout the 26 weeks of the experiment.

7. Oviposition intervals were similar for normal and coated eggs when birds were not exposed to disturbance.

8. Disturbance of hens increased oviposition intervals and the incidence and degree of shell whitening, to a similar extent, in both populations.

9. It is concluded that stress‐related egg retention is not the sole factor responsible for abnormal egg shell whitening. Shell whitening may occur as a consequence of the premature termination of shell pigmentation as well as a consequence of the retardation of oviposition which occurs when hens are disturbed.     

浅谈减少生种发生率的体会

前几年,我所生产的“两广二号”普通种的正交种生种较多,尤以遂溪前进农场的原蚕点最为严重,特别是在2000年秋制的第一批种,生种率高达30%,甚至出现整张蚕种都是生种的情况。生种既严重影响蚕种质量,又造成了生产上的损失,导致经济效益下降,蚕种场为此大伤脑筋。我所近两年来通     

Bacterial contamination of eggs and behaviour of poultry flocks in the free range environment

The free range production system is becoming more common in Australia and is expected to increase. Free range hens are exposed to more stressors in comparison to hens from barn and cage systems and it is suggested that stress can increase bacterial shedding on eggs. The aims of this study were to examine the level of total bacteria and Enterobacteriaceae populations, as well as the presence of Salmonella and Campylobacter, in eggs collected from two free range flocks on two different farms and to conduct longitudinal observations of the behaviour and welfare of hens in the free range production system. Hen age (weeks) was shown to have a significant effect (increase) on the level of total bacteria on the egg shell surface and in shell pores, as well as having an effect on feather condition score. As the hens aged, the frequency of external visual egg characteristics increased, as did feather condition score (where feather condition was poorer). These observations indicate areas which should be investigated further to improve the food safety of eggs and optimise the welfare of free range hens.     

Individual variation in corticosterone secretion in laying hens

1. Plasma corticosterone responses to a handling and isolation stressor were measured in laying hens once, before two groups were mixed into a single larger group, and again after the groups were mixed. Hens were bled before the stressor was applied and within 3 min of removal from groups (0 min sample), and again 15 and 45 min later 2. Social interactions were recorded throughout the experiment using continuous, all-occurrences sampling during group observations and the social rank index of each hen was calculated. 3. Plasma corticosterone was low immediately after birds were first picked up and sampled on each occasion, and rose to a peak after repeated handling, 15 min later. It then declined and was almost back to basal levels 40 min after first handling. 4. Corticosterone responses were greater 6 d before mixing (first day of sampling) than they were 1, 7 or 21 d after mixing. Corticosterone concentrations and responses were not elevated 1 d after the two groups of hens were mixed. 5. Variation in corticosterone concentrations and responses within and between hens was quantified by calculating coefficients of variation of corticosterone concentrations and areas under corticosterone response curves. Variation tended to be less within than between hens. 6. There was a transient increase in aggressive interactions immediately after mixing. One bird was clearly dominant in each observed dyadic interaction and hierarchies tended to strong linearity in all groups. Social rank was not related to corticosterone concentrations or responses. 7. Area under the corticosterone response curve can be used to compare differences between and within laying hens in their responsiveness to a handling and isolation stressor.     

Individual variation in blood magnesium and susceptibility to hypomagnesaemia in cows

1. Within a normal range for blood magnesium in cows, 1.55-3.0 mg of Mg per 100 ml of serum or plasma, statistically significant differences between individuals were detected.
2. Reference was made to studies of the renal handling of magnesium and to demonstrations in the literature of large individual variations in the ability of cows to utilize magnesium from the diet. It is logical to assume that such variations will contribute to the creation of individual differences in plasma levels of the element. The point was emphasized that to moderate differences in plasma concentration can correspond large quantitative differences in magnesium metabolism.
3. A positive correlation was demonstrated in one herd between earlier individual plasma magnesium levels within the normal range and decreased levels after one week on a tetany-producing pasture.
4. Gows with initial plasma magnesium values in the lower part of the range of a group of animals appeared specially susceptible to disease when subsequently the whole group was subjected to hypo- magnesaemia-producing conditions. This rule was detected within the limited material from the mentioned herd with tetany and also in materials from the literature.
5. The possibility that certain individuals within herds can be pointed out as specially susceptible to hypomagnesaemic disturbances before the beginning of a tetany season may be of practical interest.

     

Individual production differences do not explain cannibalistic behaviour in laying hens

1. Sixty-three laying hens were collected from 5 commercial farms experiencing outbreaks of cannibalism. It is known that cannibalistic behaviour varies strongly between hybrids and between individuals of the same hybrid. The aim of this study was to test specific hypotheses about the causation of cannibalism by comparing matched individuals varying in their cannibalistic behaviour. 2. To investigate feed efficiency, egg production and feed consumption, data were collected over 30 d. Nutrient deficiencies have been associated with outbreaks of cannibalism and we hypothesised that cannibals are more feed efficient than their flock mates and, therefore, more susceptible to transient nutrient deficiencies or imbalances that trigger cannibalistic behaviour. 3. Video recordings were made of victims of cloacal cannibalism and their matched controls during oviposition. Victims were expected to have longer oviposition durations and a higher incidence of short-term cloacal prolapses than controls, because the starting point for cannibalism is often suggested to be pecking at the red mucosa of the victim during, or just after, oviposition. 4. Oviduct swab samples were taken from surviving victims of cloacal cannibalism and their matched controls 4 weeks after the cannibalistic attack. If peck wounds provide a route for subsequent bacterial invasion of the reproductive tract, victims would be expected to have greater bacterial colonisation of the oviduct. 5. Mortality within each matched trio was recorded over a 23-month period after the cannibalistic attack. Victims that survived a cannibalistic attack were expected to have reduced longevity compared to controls and cannibals. This could occur if they developed secondary infections as a result of the cannibalistic attack, or if they had poorer health even before the attack. 6. No significant differences were found between cannibals, victims and controls in feed efficiency or any of the production variables measured. Victims of cloacal cannibalism did not expose their cloacal mucosa more, or for longer, than matched control hens during oviposition, and had no more bacteria in their oviduct. Victims tended to die sooner than their matched cannibals or cannibals during a 23-month period after a cannibalistic attack.     

籽鹅卵巢5个基因产蛋前期与产蛋期mRNA表达的研究

为了进一步分析从消减文库获得的未知基因表达与产蛋性能的相关性,利用SYBR GreenⅠ实时荧光定量PCR方法分析籽鹅卵巢组织中5个基因EST4、EST5、EST6、EST7和EST8产蛋前期与产蛋期的mRNA表达。结果显示,EST4、EST5、EST6、EST8的产蛋期表达量显著高于产前期(P<0.05),EST7的产蛋期表达量极显著高于产蛋前期(P<0.01)。研究结果提示,这5个基因参与鹅产蛋性状的分子调控。     

Storage of sperm in the uterovaginal junction and its incidence on the numbers of spermatozoa present in the perivitelline layer of hens' eggs

1. The numbers of spermatozoa found in the perivitelline layer (perivitelline spermatozoa) of hens' eggs during a 14-d period after insemination were found to be log-dose dependent (r = 0.99) on the quantities of spermatozoa inseminated intravaginally in these hens (50, 100, 200 or 400 million/female). 2. Highly significant correlations were also observed between the perivitelline spermatozoa and the proportion of uterovaginal sperm-storage tubules containing spermatozoa on day 14 after insemination. 3. These data confirm that the number of perivitelline spermatozoa in eggs laid on day 2 after artificial insemination (AI) are highly correlated with the mean percentages of fertility of its duration over a 14-d or 24-d period. As a consequence, eggs laid by the 10% highest or the 10% lowest females primarily classified on the basis of this variable exhibited on average 99% or 49.7% fertility, respectively, over a two-week period after AI.     

Effects of the age of male and female broiler breeders on sexual behaviour, fertility and hatchability of eggs

1. The effects of the age of male and female broiler breeders on fertility, hatchability and sexual behaviour were determined in two 2x2 factorial experiments. In the 1st, male and female birds 27 to 29 and 35 to 37 weeks and in the 2nd at 35 to 37 and 55 to 57 weeks of age were compared. 2. Fertility was not affected by the age of the males or females. 3. Early embryo deaths were higher and hatchability of fertile eggs was lower in eggs from females aged 27 to 29 and 55 to 57 weeks compared with eggs from birds aged 35 to 37 weeks. 4. There were no differences in male display behaviours at any age. The number of observed matings were higher in young males 27 to 29 weeks old compared with males 35 to 37 and 55 to 57 weeks of age. There were no detectable differences in the responses of the females to the males at different ages. 5. Plasma testosterone concentration in males increased from 24 to 30 weeks of age and was relatively constant from 36 to 60 weeks. Plasma oestrogen in females was high at 24 and lowest at 30 weeks of age after which it increased. 6. The results suggest that there may be little difference in the fertility of male and female broiler breeders at different ages when body weight is adequately controlled to at least 60 weeks of age.     

Rolling behaviour of sows in relation to piglet crushing on sloped versus level floor pens

The study focused on the rolling behaviour of sows and the crushing of piglets by sows' rolling behaviour. The experiment examined the influence of sloped floor in loose housed farrowing pens on the rolling behaviour of sows and crushing of piglets. The experimental unit was made up of 24 pens. There were two experimental pen designs with piglet creep in the corner of the pen and piglet creep across the end of the pen, respectively. Both of the experimental pen designs had a 10% sloped floor in the sow's resting area. The two control pen designs were identical to the experimental pen designs, but with a level floor. The behaviour of 85 sows and their litters was continuously video recorded. Behavioural observations were made from birth of the first piglet and until 3 days after birth of the first piglet. Rolling behaviour of sows caused significantly more trapped piglets under the sow than lying down from standing (P = 0.04). Rolling behaviour caused 64% of the trapped piglets and lying down from standing caused 36% of the trapped piglets. Rolling from udder to side without protection trapped significantly more piglets than rolling from udder to side near slanted wall or piglet protection rails and rolling from side to udder (P < 0.001). With a certain pen design sloped floor reduced rolling from udder to side without protection (P = 0.007) and reduced the number of trapped piglets (P = 0.01), but results concerning lying behaviour showed that sloped floor pushed sows to rest on the level part of the floor. The results indicate that rolling behaviour that crushes piglets can be reduced, and sows prefer to lie on a level floor.     

Association between floor type and behaviour, skin lesions, and claw dimensions in group-housed fattening bulls

Rubber mats covering concrete slatted flooring are a developing market in dairy barns but remain rare in beef cattle facilities. The aim of this study was to investigate the effects of covering slatted concrete floor with perforated rubber mats on behaviour and occurrence of skin and claw lesions in fattening bulls. The groups of six bulls each with a total average age of 9.8 months were kept over 1 year on either slatted concrete (CONCRETE PEN) or on slatted concrete covered completely (RUBBER PEN) or partially (CHOICE PEN) with perforated rubber mats. Every quarter-year, behaviour (preference of flooring, lying, aggression, mounting) was recorded. In two-weekly intervals the incidence of skin lesions was examined. At 12 and 18 months of age the rising time of the bulls was measured. At the beginning of the study and after slaughter claw dimensions were recorded. Bulls in the CHOICE PEN preferred (P<0.01) the rubber coated area throughout the experiment. Animals in the RUBBER and the CHOICE PENS showed more lying periods (P<0.01) and had a lesser incidence of skin lesions (P<0.01) compared to bulls in the CONCRETE PEN. Bulls in the CHOICE PEN needed less time for rising (2.7+/-0.3s) than bulls in the CONCRETE PEN (4.4+/-0.5s, P<0.01). Net claw growth differed significantly between all pens (RUBBER>CHOICE>CONCRETE; P<0.05). In conclusion, the results of this study indicate that rubber coated slatted flooring has a positive influence on the housing conditions of beef cattle.     

The effect of floor space allowance on feedlot performance and on behaviour of Israeli-Friesian male cattle

Four groups of Israeli-Friesian male cattle were fattened in pens with concrete slatted floors from an initial live weight of 138 kg up to 450 kg at slaughter. Floor space per animal differed between groups, of which two were fed ad lib. and two restricted. One group had an adjoining uncovered yard. Both DM intake and daily gain different significantly from the 150th day to slaughter. The differences were directly related to floor space allowance per animal. Animals of the smaller space allowance had a significantly higher dressing percentage, but they were not significantly fatter.     

Genetic variation in sows' maternal behaviour, recorded under field conditions

The present study presents heritabilities for several maternal behavioural traits of sows recorded under field conditions (by the farmer) in Norwegian (N) and Finnish (SF) nucleus herds. Based on questionnaires to the farmers, maternal behaviour was scored on a scale from 1 to 7 for 11 traits in the Norwegian study and 5 of the same traits in the Finnish study. Based on the full relationship matrixes, significant heritabilities were found for the same traits in the two countries' breeding herds. The highest heritabilities were found for the sow's reaction to piglet screaming when handled (h²=0.16 (N), h²=0.12 (SF)), how often the sow showed fear during routine management (h²=0.14 (N), h²=0.17 (SF)), aggression towards humans (h²=0.11 (N)) and protests by the sow when moved to the farrowing pen (h²=0.00 (N) but h²=0.22(SF)). Except for the last trait, the results were very consistent across countries. The study shows that field recording of maternal behaviour with questionnaires is one way of detecting genetic variation between sows and seems to work in a large scale, under field conditions. Some of the estimated heritabilities were higher than corresponding heritabilities based on behavioural tests presented in previous studies. Sows' reaction to piglets screaming when handled, sows' fear of humans and sows' aggressive behaviour towards humans are possible candidate traits for selection.     

Effect of rearing factors on the prevalence of floor eggs, cloacal cannibalism and feather pecking in commercial flocks of loose housed laying hens.

1. Effects of rearing conditions on behavioural problems were investigated in a cohort study of commercial flocks of laying hens housed in 2 different loose housing systems. The sample population was 120 385 laying hens from 59 flocks of various hybrids at 21 different farms. 2. Logistic regression modelling was used to test the effects of selected factors on floor eggs, cloacal cannibalism and feather pecking. In addition to early access to perches or litter, models included hybrid, stocking density, group size, housing system, age at delivery, identical housing system at the rearing farm and at the production farm and, in models for floor eggs and cloacal cannibalism, nest area per hen. Odds ratios were calculated from the results of the models to allow risk assessment. 3. No significant correlations were found between the prevalence of floor eggs, cloacal cannibalism and feather pecking. 4. Access to perches from not later than the 4th week of age decreased the prevalence of floor eggs during the period from start-of-lay until 35 weeks of age, odds ratio 0-30 (P<0-001). Furthermore, early access to perches decreased the prevalence of cloacal cannibalism during the production period, odds ratio 0-46 (P=0.03). 5. No other factor had a significant effect in these models. Although it was not significant, early access to litter had a non-significant tendency to reduce the prevalence of feather pecking.     

Individual variation in the content of free amino acids observed in the blood and muscle of chicks fed a single meal daily

1. Fifty broiler chicks in individual cages, were fed on a balanced diet ad libitum until 10 d old and then given a single meal daily. Blood and pectoral muscle samples were taken from each. Free aspartic acid, threonine, serine, glutamic acid, glycine, alanine, valine, cystine, isoleucine, leucine, phenylalanine, lysine and arginine were determined.

2. Free amino acid concentrations varied greatly between birds. Values for the coefficient of variation ranged from 0.21 for serine in both tissues to 0.571 and 0.749 for valine and lysine in blood and muscle respectively.

3. Many correlations for pairs of amino acids did not seem related to the body weight of chicks.