scholarly journals Examination of the causes of mortality in non-beak-trimmed pure line laying hens with special regard to aggression

2020 ◽  
Vol 24 (1) ◽  
pp. 67-79
Author(s):  
Zoltán Zomborszky ◽  
Milisits Gábor ◽  
Zoltán Budai ◽  
Sándor Szász ◽  
Olga Pőcze ◽  
...  

The experiment was started with 1,508 Rhode Island Red (RIR) and 1,820 Rhode Island White (RIW) type non-beak-trimmed day-old pullets, which were originated from 58 RIR and 70 RIW different pedigree cocks, respectively. From all of the 128 cocks 26 half sibling offspring were tested. The pure line pullets were raised up to 18 weeks of age in a closed building, in deep litter pens and moved to the laying house and placed into three types of keeping systems [furnished cage, alternative pen (litter and floor) and conventional cage] thereafter. The number of dead birds and the cause of mortality were recorded daily during the whole rearing and egg-laying period, up to 72 weeks of age. During the rearing period the most frequent cause of mortality was wasting, which accounted for nearly 36% of the total mortality. Aggression was responsible for 28.3% of the total mortality. Depending on the type of the pullets (RIR or RIW), differences were observed in the frequency of occurrence of mortality causes. For example, oedema and beak deformation occurred only in the RIR, whereas technological injury and aggression only in the RIW pullets during the rearing period. During the egg-laying period aggression was the most common cause of mortality. Its lowest occurrence was observed in the alternative pens. In both of the examined types there were found cocks, whose offspring died exclusively by aggression, and cocks, whose offspring did not show any loss due to aggression. The ratio of these cocks differed significantly (P<0.05) between the two types examined. Based on the results it was established that the genetic background has significant effect on the mortality caused by aggression in non-beak-trimmed laying hens.

Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 500
Author(s):  
Gábor Milisits ◽  
Sándor Szász ◽  
Tamás Donkó ◽  
Zoltán Budai ◽  
Anita Almási ◽  
...  

The experiment was carried out with altogether 1740 non-beak-trimmed laying hens, which originated from Bábolna TETRA Ltd., representing two different types (Rhode Island Red (RIR) and Rhode Island White (RIW)) and four different lines (Lines 1–2: RIR, Lines 3–4: RIW). The plumage and body condition of randomly selected 120 hens (30 hens/line) was examined at 20, 46, and 62 weeks of age. The egg production and the mortality of the sampled hens were recorded daily. Based on the results, it was established that the lines differ clearly in most of the examined traits. It was also pointed out that injurious pecking of the hens resulted not only in damages in the plumage but also in the body condition. The results obviously demonstrated that the highest egg production and the lowest mortality rate were reached by those hens, which had the best plumage and body condition. Because the occurrence of injurious pecking seems to depend on the genetic background, selection of the hens (lines, families, individuals) for calm temperament will be very important in the future in order to maintain the high production level in non-beak-trimmed layer flocks.


2020 ◽  
Vol 19 (1) ◽  
pp. 83-92
Author(s):  
Johana Goyes Vallejos ◽  
Karim Ramirez-Soto

Causes of embryonic mortality in Espadarana prosoblepon (Anura: Centrolenidae) from Costa Rica. Members of the family Centrolenidae—commonly known as “glass frogs”—exhibit arboreal egg-laying behavior, depositing their clutches on riparian vegetation. Few studies have investigated specific causes of mortality during embryonic stages, perhaps the most vulnerable stage during the anuran life cycle. The Emerald Glass Frog, Espadarana prosoblepon, was used as a case study to investigate the causes of embryonic mortality in a species with short-term (i.e., less than 1 day) parental care. The specific sources of mortality of eggs of E. prosoblepon were quantified and overall rates of survival (hatching success) were estimated. Nineteen egg clutches were transferred from permanent outside enclosures to the wild. Clutch development was monitored daily until hatching; five mortality causes were quantified: desiccation, failure to develop, fungal infection, predation, and “rain-stripped.” The main causes of mortality were predation (often by katydids and wasps) and embryos stripped from the leaf during heavy rains. The results were compared to those of previous studies of centrolenids exhibiting parental care, and discussed in the context of the importance of the natural history data for these frogs with regard to understanding the evolutionary history of parental care in glass frogs.


1934 ◽  
Vol 24 (4) ◽  
pp. 636-648 ◽  
Author(s):  
J. S. Willcox

SummaryA nitrogen balance experiment of ten weeks' duration with two Rhode Island Red laying hens is described.The observed variations in the retention of nitrogen for egg-producing purposes do not appear to be connected with the output of egg nitrogen or with the number of eggs laid in the various egg cycles.The view held by other workers that the nitrogen required for egg production can be largely if not entirely drawn from the food supplied during the laying period is confirmed.The marked storage of nitrogen which has been shown to occur immediately prior to the commencement of egg laying is not repeated during the laying period, and it is suggested that during a period of heavy egg production synthesis of the nitrogenous constituents of the egg proceeds at a fairly uniform rate.


Toxins ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 156
Author(s):  
Ling Zhao ◽  
Yue Feng ◽  
Jing-Tao Wei ◽  
Meng-Xiang Zhu ◽  
Lei Zhang ◽  
...  

The objective of this study was to evaluate the efficacy of mycotoxin binders in reducing the adverse effects of co-occurring dietary aflatoxin B1 (AFB1), deoxynivalenol (DON) and ochratoxin A (OTA) on laying hens. Three hundred and sixty 26-week-old Roman laying hens were randomly allocated into four experimental groups with 10 replicates of nine birds each. The four groups received either a basal diet (BD; Control), a BD supplemented with 0.15 mg/kg AFB1 + 1.5 mg/kg DON + 0.12 mg/kg OTA (Toxins), a BD + Toxins with Toxo-HP binder (Toxins + HP), or a BD + Toxins with TOXO XL binder (Toxins + XL) for 12 weeks. Compared to the control, dietary supplementation of mycotoxins decreased (P < 0.10) total feed intake, total egg weight, and egg-laying rate, but increased feed/egg ratio by 2.5–6.1% and mortality during various experimental periods. These alterations induced by mycotoxins were alleviated by supplementation with both TOXO HP and XL binders (P < 0.10). Furthermore, dietary mycotoxins reduced (P < 0.05) eggshell strength by 12.3% and caused an accumulation of 249 μg/kg of DON in eggs at week 12, while dietary supplementation with TOXO HP or XL mitigated DON-induced changes on eggshell strength and prevented accumulation of DON in eggs (P < 0.05). Moreover, dietary mycotoxins increased relative liver weight, but decreased spleen and proventriculus relative weights by 11.6–22.4% (P < 0.05). Mycotoxin exposure also increased alanine aminotransferase activity and reduced immunoglobulin (Ig) A, IgM, and IgG concentrations in serum by 9.2–26.1% (P < 0.05). Additionally, mycotoxin exposure induced histopathological damage and reduced villus height, villus height/crypt depth, and crypt depth in duodenum, jejunum and (or) ileum (P < 0.05). Notably, most of these histological changes were mitigated by supplementation with both TOXO HP and XL (P < 0.05). In conclusion, the present study demonstrated that the mycotoxin binders TOXO HP and XL can help to mitigate the combined effects of AFB1, DON, and OTA on laying hen performance, egg quality, and health.


2021 ◽  
pp. 101211
Author(s):  
R. Scappaticcio ◽  
J. Garcia ◽  
G. Fondevila ◽  
A.F. de Juan ◽  
L. Cámara ◽  
...  

Author(s):  
Adam Kraus ◽  
Lukáš Zita

The aim was to assess the internal and external quality of consumer eggs of egg‑laying hens of two selected genotypes depending on their age. All of these hens were kept in enriched cages. There were compared eggs from Hy‑Line Brown and ISA Brown hens at the age from 36 to 64 weeks. In total, 3840 eggs from 300 hens were evaluated. Quality of eggs was determined by their technological value. Statistically significant interactions (P = 0.001) between age and genotype were found in all evaluated parameters except for the yolk colour (P = 0.044), whereas there was not found interaction (P = 0.072) between age and genotype in eggshell strength. The significant effect of hens’ age was found in all evaluated parameters, with the only exception of the yolk colour. The results showed that the average weight of eggs, eggshell, albumen and yolk increased with the age. Also the eggshell proportion, its colour and yolk index values ​​increased, whereas the egg shape index, eggshell thickness and strength, albumen proportion, Haugh units, the albumen and the yolk index decreased. Statistically significant effect of the genotype was found in all evaluated parameters except for the yolk index. When comparing both genotypes, the eggs from ISA Brown hens had a better quality. The trend of deteriorating egg quality with age was confirmed.


Author(s):  
Hasan Eleroğlu

In this study, the effects of coat difference and breeding age on the internal and external quality of the eggs were investigated in white laying hens in different cages. The eggs obtained from a total of one hundred fifty eggs White layer pure line hens at 24, 28, 32, 36 and 40 weeks of age that housing in individual cages in the Ankara Poultry Research Institute were used. Shape Index, egg weight (g), albumen height (mm), Roche scale, Haugh unit and shell strength (N) values were examined in 438 eggs obtained from these chickens found in these cages which are three tiers as upper, middle and bottom. In addition, temperature and humidity values in the tiers were recorded at 30-minute intervals during the study and then they were analysed. Statistically significant differences were calculated between temperature and humidity values measured in tiers. Although there was no difference between the tiers in terms of shape index and egg weight, the effect of age was significant. The effect of age and tiers difference on albumen height (mm) was insignificant. The Roche scale and shell strength (N) values were significantly influenced by the tier difference and breeding age. In general, it was concluded that the effect of the tier difference on the Haugh unit was insignificant, but the age was found to have an effect on the Haugh unit.


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