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PubMed1987

Effects of beak trimming and restraint on heart rate, food intake, body weight and egg production in hens.

1. Heart rate (measured on restrained hens in two experiments) was used as an indicator of short term fear and pain responses of light and heavy strains of hens subjected to beak trimming. 2. In the first experiment 3 mm of the upper and lower mandibles was trimmed, while in the second 0, 2, 4, 6 and 8 mm of upper and lower mandibles were removed. 3. Production responses to beak trimming were measured after trimming, for 4 weeks in experiment 1 and for 10 weeks in experiment 2. 4. In the first experiment the recovery of beak trimmed hens to normal heart rate took significantly longer than that of control hens subjected only to catching and restraint, suggesting that there was short term pain associated with beak trimming. 5. The heavier strain took about 4 min longer to return to a normal heart rate than the lighter strain, indicating a strain difference in responsiveness to beak trimming. 6. Trimming the hens' beak by 3 mm had no significant effect on rate of lay or body weight, but their mean egg weight was depressed and food intake took 9 to 10 d to recover to pre-trimming values. 7. In the second experiment a plateau was reached in recovery time of the heart rate once 4 mm of beak was removed. Removal of 4, 6 and 8 mm of beak depressed normal feeding and resulted in variable effects on production and body weight.

Animals↗
PubMed2000

Vocal tract function in birdsong production: experimental manipulation of beak movements.

Kinematic analyses have demonstrated that the extent to which a songbird's beak is open when singing correlates with the acoustic frequencies of the sounds produced, suggesting that beak movements function to modulate the acoustic properties of the vocal tract during song production. If motions of the beak are necessary for normal song production, then disrupting the ability of a bird to perform these movements should alter the acoustic properties of its song. We tested this prediction by comparing songs produced normally by white-throated sparrows and swamp sparrows with songs produced when the beak was temporarily immobilized. We also observed how temporarily loading the beak of canaries with extra mass affected vocal tract movements and song production. Disruption of vocal tract movements resulted in the predicted frequency-dependent amplitude changes in the songs of both white-throated sparrows and swamp sparrows. Canaries with mass added to their beak sang with their beak open more widely than normal and produced notes with greater harmonic content than those without weights. Both manipulations resulted in acoustic changes consistent with a model in which beak motions affect vocal tract resonances, thus supporting the hypothesis that dynamic vocal tract motions and post-production modulation of sound are necessary features of normal song production.

Acoustics↗
PubMed1995

Influences of age at final beak trim on the productive performance of commercial layers.

Two commercial egg-type strains were beak-trimmed at 10, 10 and 63, or 10 and 84 d. There were no interactions between strain and beak trimming treatment. Pullet feed consumption was significantly reduced within the 14-d period following beak trimming at 63 or 84 d. Total pullet feed consumption (1 to 126 d) was significantly lower among birds trimmed twice than among those trimmed only at 10 d. At 126 d, body weight of pullets trimmed at 10 and 84 d or 10 and 63 d was significantly less than that of those trimmed only at 10 d. Pullet mortality was not significantly influenced by beak trimming treatments. No significant effects of beak trimming treatments on layer mortality, egg production, egg weight, egg mass, feed conversion, or egg quality were detected. Layer feed consumption was significantly greater among birds beak trimmed at 10 d than among those trimmed at 10 and 84 d. Most of the effects associated with beak trimming treatments can be attributed to the influence that beak trimming had on feed consumption.

Age Factors↗
PubMed1996

The effect of beak trimming on two strains of commercial tom turkeys. 2. Behavior traits.

The influence of beak trimming of two strains of commercial male turkeys (Strains A and B) on behavior during the growing period was investigated. Poults were either left with beaks intact or arc beak trimmed at hatching. Strain by beak treatment interactions were generally lacking, indicating that these two strains responded similarly. Beak trimming did not influence tameness (as measured by response to a novel object at 16 wk), fearfulness (as measured by tonic immobility response at 18 wk), or resting behavior from 3 to 15 wk of age. When compared to birds with intact beaks, birds with trimmed beaks spent more time standing during the week of hatching and were observed eating more often at 2 wk of age. Strain B birds were more tame, less fearful, and rested more at 8 and 11 wk of age than Strain A birds. Results of the current study indicate that the influence of arc beak trimming at hatching on behavior of male turkeys at hatching did not appear to have a lasting negative impact on their well-being.

Aging↗
PubMed1991

Region-specific expression of scutate scale type beta keratins in the developing chick beak.

This study shows that different patterns of scutate scale type beta keratins are accumulated in the three adjacent structures of the embryonic chick beak: periderm, egg tooth, and cornified beak. The cornified beak accumulates all of the beta keratins of scutate scale except pp2,3. The periderm, which is the outermost, multilayered covering of the whole embryonic beak, accumulates only beta keratins 2,3, and p2,3 of the scutate scale pattern. The egg tooth, which is the rounded elevation on the dorsal surface of the upper beak, and the embryonic claw accumulate greatly reduced levels of 2,3 and p2,3 compared to scutate scale. Like cornified beak, the claw does not accumulate pp2,3, but both tissues express a potentially new beta keratin, beta keratin 8. Neither the histidine rich "fast" proteins (HRPs), which are expressed in embryonic scutate scales and feathers, nor the avian cytokeratin associated proteins (cap-1 and cap-2), which are expressed in scutate and reticulate scales, are expressed in any of the embryonic beak structures or in the claw. The implications of these findings with regard to regulation of terminal differentiation of avian skin are discussed.

Animals↗
PubMed1976

The cells that secrete the beaks in octopods and squids (Mollusca, Cephalopoda).

A single layer of cell secrets the hard cephalopod beaks. The beccublasts are tall columnar cells that separate the beak from the surrounding buccal muscles, and must serve to attach these muscles to the beak. Within the cell layer there are three types of cells. The first, and most frequently found contain cell-long fibrils. These fibrils may have contractile and tensile properties. Complex trabeculae extend from the beccublasts into the matrix of the beak. The fibrils are attached to these trabeculae and at the other end of the cells they are anchored near to the beccublast-muscle cell interface, closely associated with the muscles that move the beak. The second group of cells contain masses of endoplasmic reticulum the cysternae of which are arranged along the long axis of the cell. These cells also contain dense granules and are probably the major source of beak hard tissue. It is probable that each cell secretes its own column of beak hard tissue. The third group of cells cells contains a mixture of fibrils and secretory tissue. In the beccublast layer there are changes in the proportion of the three types of cells depending upon the region sampled. In the region where growth is most active there are mostly secretory cells, whereas near the biting and wearing tip there are mainly anchoring type cells.

Animals↗
PubMed2002

Ontogeny of behaviour in intact and beak trimmed layer pullets, with special reference to preening.

1. The effects of commercial beak trimming on layer pullet behaviour were investigated, with special reference to preening. 2. One-d-old chicks, 96 in all, were housed in 12 litter floor pens, with 8 birds in each, to 20 weeks of age. Approximately one quarter of the beak was trimmed in all birds in half of the pens (BT) at 8 d of age using a hot blade debeaker. The birds in the other pens remained intact (NBT). 3. There was no significant effect of beak trimming on body weight at any age. At the end of the study, upper mandible lengths were shorter in BT birds. 4. Beak trimming had very little effect on behaviour. NBT birds showed more litter-directed behaviour than did BT birds, and BT birds spent more time in preening directed at the preen gland, and at the back while sitting. 5. Feather damage was minimal and there was no difference in mean feather damage scores between treatments at any age. 6. The young age and small amount of beak removed during beak trimming may be at least partly responsible for the lack of effects of beak treatment on behaviour and plumage condition.

Age Factors↗
PubMed2006

Effects of beak trimming and cage design on laying hen performance and egg quality.

1. Conventional cages are to be replaced by furnished cages or aviary systems to improve the welfare of hens. We compared the performance and egg quality of hens reared in two designs of furnished cages and of two standard cages. We also explored the consequences of the absence of beak trimming when using these designs. 2. Hens (2028) were housed from 18 to 70 weeks of age in 108 standard cages at 6 per cage (60 cmx63.5 cm), in 96 cages at 5 per cage (59.5 cmx55.5 cm) or in two designs of furnished cage at 15 per cage (24 F15M cages and 36 F15P cages made by two manufacturers) which contained equipment varying in size and location (nests, dust baths and perches). Half of the hens were beak-trimmed in each design. 3. Mortality was low in beak-trimmed hens (<5%) but was unacceptably high in non-beak-trimmed hens due to cannibalism (>40%, 516 hens). Mortality was worse in standard cages than in furnished cages. Consequently, hen-housed egg production was significantly lowered in non-beak-trimmed hens. 4. Egg laying in beak-trimmed hens reared in furnished cages occurred mainly in the nest (80 and 84.8% in F15M and F15P) but also in the dust bath (13.3 and 9.4% in F15M and F15P) and in other parts of the cage (6.7 and 5.8% in F15M and F15P). 5. The total percentage of broken (visual observation) and hair-cracked eggs (candling) was high in the furnished cage designs (15.4 and 19.6% in F15M and F15P, respectively) compared with standard cage designs (8.1 and 12.2% in S6 and S5). This was mainly due to hair-cracked eggs, the highest percentages occurring in the nests, especially in the design with a narrow nest and no egg saver (11.1% in F15M compared to 17.6% in F15P) as a consequence of egg accumulation in the cradle and relatively low frequency of manual egg collection. 6. Eggshell quality (index and breaking strength) was only slightly influenced by cage effects so differences in egg breakage were attributable to impacts related to cage design. 7. It is concluded that beak trimming remains the most effective way to prevent cannibalism, although furnished cages with a large group of hens slightly reduced the incidence, and that further development and optimisation of furnished cages is needed to reach egg quality similar to standard cages.

Animal Husbandry↗
PubMed2005

Stable isotopes, beaks and predators: a new tool to study the trophic ecology of cephalopods, including giant and colossal squids.

Cephalopods play a key role in the marine environment but knowledge of their feeding habits is limited by lack of data. Here, we have developed a new tool to investigate their feeding ecology by combining the use of their predators as biological samplers together with measurements of the stable isotopic signature of their beaks. Cephalopod beaks are chitinous hard structures that resist digestion and the stable isotope ratios of carbon (delta13C) and nitrogen (delta15N) are indicators of the foraging areas and trophic levels of consumers, respectively. First, a comparison of delta13C and delta15N values of different tissues from the same individuals showed that beaks were slightly enriched in 13C but highly impoverished in 15N compared with lipid-free muscle tissues. Second, beaks from the same species showed a progressive increase in their delta15N values with increasing size, which is in agreement with a dietary shift from lower to higher trophic levels during cephalopod growth. In the same way, there was an increase in the delta15N signature of various parts of the same lower beaks in the order rostrum, lateral walls and wings, which reflects the progressive growth and chitinization of the beaks in parallel with dietary changes. Third, we investigated the trophic structure of a cephalopod community for the first time. Values of delta15N indicate that cephalopods living in slope waters of the subantarctic Kerguelen Islands (n=18 species) encompass almost three distinct trophic levels, with a continuum of two levels between crustacean- and fish-eaters and a distinct higher trophic level occupied by the colossal squid Mesonychoteuthis hamiltoni. delta13C values demonstrated that cephalopods grow in three different marine ecosystems, with 16 species living and developing in Kerguelen waters and two species migrating from either Antarctica (Slosarczykovia circumantarctica) or the subtropics (the giant squid Architeuthis dux). The stable isotopic signature of beaks accumulated in predators' stomachs therefore revealed new trophic relationships and migration patterns and is a powerful tool to investigate the role of the poorly known cephalopods in the marine environment.

Animal Migration↗
PubMed2001

Choreography of song, dance and beak movements in the zebra finch (Taeniopygia guttata).

As do many songbirds, zebra finches sing their learned songs while performing a courtship display that includes movements of the body, head and beak. The coordination of these display components was assessed by analyzing video recordings of courting males. All birds changed beak aperture frequently within a single song, and each individual's pattern of beak movements was consistent from song to song. Birds that copied their father's songs reproduced many of the changes in beak aperture associated with particular syllables. The acoustic consequences of opening the beak were increases in amplitude and peak frequency, but not in fundamental frequency, of song syllables. The change in peak frequency is consistent with the hypothesis that an open beak results in a shortened vocal tract and thus a higher resonance frequency. Dance movements (hops and changes in body or head position) were less frequent, and the distribution of dance movements within the song was not as strongly patterned as were changes in beak aperture, nor were the peaks in the distribution as strongly marked. However, the correlation between the positioning of dance movements within fathers' and sons' songs was striking, suggesting that the choreography of dance patterns is transmitted from tutor to pupil together with the song.

Animals↗
PubMed1998

Molecular genetic identification of southern hemisphere beaked whales (Cetacea: Ziphiidae).

To assist in the species-level identification of stranded and hunted beaked whales, we compiled a database of 'reference' sequences from the mitochondrial DNA control region for 15 of the 20 described ziphiid species. Reference samples for eight species were obtained from stranded animals in New Zealand and South Australia. Sequences for a further seven species were obtained from a previously published report. This database was used to identify 20 'test' samples obtained from incompletely documented strandings around New Zealand. Analyses showed that four of these 'test' specimens (20%) had initially been misidentified. These included two animals of particular interest: (i) a Blainville's beaked whale (Mesoplodon densirostris), the first record of this species in New Zealand waters; and, (ii) a juvenile Andrews' beaked whale (Mesoplodon bowdoini), a species known from just over 20 strandings worldwide. A published sequence from a beaked whale product purchased in the Republic of Korea was identified as a Cuvier's beaked whale (Ziphius cavirostris). Levels of intra- and interspecific variation were compared to determine the potential for misidentification when the database or taxonomy is incomplete. Intraspecific variation was generally < 2%, and interspecific divergence was generally > 4.7%. Exceptions were within-species variation in Hyperoodon planifrons, southern bottlenosed whale (4.12%), which exceeded the variation between the two species of Berardius (3.78%), and variation between the two specimens assigned to M. hectori, Hector's beaked whale (7.14%). The latter case appears to be an error in species identification, and could represent the discovery of a new species of beaked whale.

Animals↗
PubMed1999

Histopathology of the palmar beak ligament in trapeziometacarpal osteoarthritis.

Eighteen cadaver hands were studied to investigate the relationship between degeneration of the palmar beak ligament and articular disease of the trapeziometacarpal joint. Eight of 18 joints had chondromalacia alone; 10 contained areas of eburnation in the palmar aspect of the joint. Beak ligament degeneration correlated closely with the presence of articular degeneration; all joints with eburnation demonstrated frank detachment of the ligament from its metacarpal insertion site. Histologically, the collagen fibers of the beak ligament were disorganized at the metacarpal attachment. The normal insertional zone of fibrocartilage was often unrecognizable on the metacarpal side and, in more degenerative specimens, an intervening synovial recess appeared at the palmar beak of the metacarpal. The trapezial insertion of the beak ligament showed no degenerative change. Increasingly severe cartilage disease was associated with progressive and selective degeneration of the collagen framework of the beak ligament at its insertion onto the thumb metacarpal. These localized histopathologic findings further support the existence of an anatomically distinct intra-articular beak ligament essential to the normal function of the trapeziometacarpal joint and suggest an etiologic relationship to osteoarthritic disease.

Aged↗
PubMed2006

Jumbo squid beaks: inspiration for design of robust organic composites.

The hard tissues found in some invertebrate marine organisms represent intriguing paradigms for robust, lightweight materials. The present study focuses on one such tissue: that comprising the beak of the jumbo squid (Dosidicus gigas). Its main constituents are chitin fibers (15-20wt.%) and histidine- and glycine-rich proteins (40-45%). Notably absent are mineral phases, metals and halogens. Despite being fully organic, beak hardness and stiffness are at least twice those of the most competitive synthetic organic materials (notably engineering polymers) and comparable to those of Glycera and Nereis jaws. Furthermore, the combination of hardness and stiffness makes the beaks more resistant to plastic deformation when in contact with blunt abrasives than virtually all metals and polymers. The 3,4-dihydroxy-l-phenylalanine and abundant histidine content in the beak proteins as well as the pigmented hydrolysis-resistant residue are suggestive of aromatic cross-linking. A high cross-linking density between the proteins and chitin may be the single most important determinant of hardness and stiffness in the beak. Beak microstructure is characterized by a lamellar arrangement of the constituents, with a weak interface that promotes crack deflection and endows the structure with high fracture toughness. The susceptibility of this microstructure to cracking along these interfaces from contact stresses at the external surface is mitigated by the presence of a protective coating.

Animals↗
PubMed1997

Behavioural and anatomical consequences of two beak trimming methods in 1- and 10-d-old domestic chicks.

1. To examine the effects of beak trimming on behaviour, beak anatomy, weight gain, food intake and feather condition 360 ISA Brown chicks were trimmed by hot cut or cold cut at 1 d or 10 d of age or were sham-operated controls. The experiment was a 3 x 2 factorial design, with the chicks housed in littered pens in groups of 10 and observed for 6 weeks after trimming. 2. In the first week after trimming, when trimmed birds were compared with untrimmed controls, they were less active (sat and slept more), fed less, preened less and generally engaged in less beak-related behaviour. 3. These differences waned sharply during week 2 and had disappeared by week 5. There were very few differences between hot- and cold-cut birds. 4. There were also differences in production variables: trimmed birds grew more slowly during the week after trimming, their food intake was depressed for 3 weeks and food conversion efficiency improved for 2 weeks. 5. The only significant effect on feather scores was better plumage condition in the groups trimmed at 1 d and scored at 6 weeks. 6. To examine the anatomical effects 36 ISA Brown chicks trimmed by hot or cold cut at 1 d or 10 d of age were killed at 21 and 42 d after trimming, and their beaks were processed and examined histologically. In all trimmed groups healing was very rapid and no scar tissue was seen but, unlike the controls, the regrown tips contained no afferent nerves or sensory corpuscles. 7. Beak lengths immediately after trimming were 40% to 50% shorter than controls; the anatomical consequences of both methods were identical. 8. Overall, it was judged that the effects on behaviour and beak anatomy were much less severe than previously reported for birds trimmed at older ages. If birds do have to be trimmed then the procedure should be carried out in young birds: from the birds' standpoint 1 d appears to be the most suitable.

Aggression↗
PubMed1988

Effects of beak trimming at different ages on the body weight and feed conversion of guinea fowl (Numida meleagris).

The effect of beak trimming at different ages on feed consumption and growth of meat-type guineas (Numida meleagris) up to 12 wk of age was investigated. In the first experiment, beaks of birds were trimmed at 7, 28, 49, and 70 days, respectively. In the second experiment, beak trimming was done at 42, 49, 56, and 63 days, respectively. Body weight, feed consumption, and mortality were measured first at 4 wk and weekly thereafter in both experiments. Beak trimming of keets at 7 days, significantly (P less than .05) reduced body weights at 4, 8, and 12 wk whereas beak trimming at 70 days significantly (P less than .05) reduced body weights at 12 wk. Beak trimming at other ages did not produce significant differences in body weights or feed conversions. Mortality was low (2 to 4%) throughout.

Age Factors↗
PubMed1989

Effects on turkey mortality and body weight of type of beak trimming, age at trimming, and injection of poults with vitamin and electrolytes solution at hatching.

This study was designed to determine the influence of: 1) age at and type of beak trimming (BT), and 2) injection of poults at hatch with 2 mL of a commercial mineral and vitamin solution versus noninjection of poults on the viability and growth rate of turkeys to market age. Mortality from 0 to 20 wk of age and BW at 8, 16, and 20 wk of age were recorded. At hatch, poults were BT 1.0 mm (Experiment 1) or 1.5 mm (Experiment 2) anterior to the nostril using an electric arc beak trimmer. In a second treatment (Experiments 1 and 2), one-third to one-half of the beak was removed at 11 days of age with a hot blade beak trimmer. In Experiment 1, offspring from three large-bodied crosses were used whereas in Experiment 2 birds were from a single large-bodied cross. The BT at 1.0 mm anterior to the nostril with an electronic beak trimmer (Experiment 1) increased mortality and decreased BW at 8, 16, and 20 wk of age relative to BT at 11 days of age with the hot blade beak trimmer. The BT at 1.5 mm (Experiment 2) at hatching did not affect mortality and reduced BW only at 8 wk of age relative to BT at 11 days of age. The use of an injectable commercial vitamin-mineral solution did not influence mortality in either experiment and significantly increased BW only at 8 wk of age in Experiment 2. The interactions of strain cross with either age of BT or injection vs. noninjection of poults were NS in Experiment 1.

Age Factors↗
PubMed1990

Influence of age at final beak trimming on pullet and layer performance.

Effects of final beak trimming on pullet and layer productivity were examined with three strains of commercial layers. All pullets were precision-trimmed at 7 days with final beak trimming at either 63, 84, or 105 days. Transient depressions of pullet body weight and feed consumption were noted in the periods immediately following beak trimming. Pullet mortality from 7 to 18 wk of age and 18-wk body weight were not significantly affected by beak trimming treatments. Strain effects were noted in rate of feed consumption following beak trimming. Age at 50% production was significantly later among birds trimmed at 63 days than among those trimmed at 84 or 105 days. Feed consumption, egg production, and mortality (140 to 441 days) were significantly lower among birds trimmed at 63 days than among those trimmed at 84 or 105 days. Egg quality and size were not influenced by beak trimming treatments.

Aging↗
PubMed1991

Beak trimming effects on behavior patterns, fearfulness, feathering, and mortality among three stocks of White Leghorn pullets in cages or floor pens.

White Leghorn pullets of the Y1, Y2, and North Central Randombred (NCR) experimental stocks were used. Half of the birds of each stock had half of the upper and less of the lower mandible removed at 4 wk of age by making a V-shaped cut as viewed from the side (BT), whereas the other half retained their beaks intact (IN). Pullets were moved from growing pens to a layer house at 18 wk of age. Seventy-two cages and 30 floor pens were filled with 6 and 20 birds per unit, respectively. Pullets within a cage or floor pen were all of the same genetic stock and beak treatment. All measurements were performed within 10 wk after housing, except for mortality in cages. When kept in cages, genetic stocks did not show behavioral differences. However, in floor pens, stock differences were detected in feeding, crouching, and nonaggressive pecking. When kept in cages, the stocks also differed in 24-wk body weight, weight gain from 18 to 24 wk, and certain measures of fearfulness in both cages and pens, and in feather condition at 21 and 22 wk. Mortality from cannibalism and hen-days survival of caged IN pullets differed among genetic stocks. Mortality from cannibalism was absent among pullets kept in experimental floor pens. In cages, BT pullets were less active, gained less weight, and had lower incidence of cannibalism than IN pullets. Also, BT pullets were less nervous and had better feather condition than IN pullets. However, trimming beaks to prevent cannibalism was less effective in NCR pullets than in Y1 or Y2 pullets. In floor pens, BT pullets showed less activity and reduced feeding frequency and less fearfulness as indicated by duration of induced tonic immobility. Agonistic behaviors were not different between BT and IN pullets. From these results, beak trimming could be interpreted as having either stressful or stress-alleviating effects, depending on the criteria used. However, proper beak trimming appears beneficial when cannibalistic pecking is likely to be a problem. The relative benefits of beak trimming vary among genetic stocks.

Agonistic Behavior↗