Cemental Deposition, Tooth Succession, and Horn Development as Criteria of Age in Dall Sheep

1969 ◽  
Vol 33 (3) ◽  
pp. 552 ◽  
Author(s):  
James E. Hemming
Keyword(s):  
Horn Development

Horn growth patterns of Nubian ibex from the Sinai, Egypt

Mammalia ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Omar Attum ◽  
Alaaeldin Soultan ◽  
Louis C. Bender
Keyword(s):  
Natural History ◽  
Arid Environment ◽  
Growth Patterns ◽  
Non Invasive ◽  
Significant Relationships ◽  
Horn Growth ◽  
Younger Age ◽  
Invasive Method ◽  
Viable Method ◽  
Horn Development

Abstract Documenting patterns of horn growth and horn-age relationships of Nubian ibex (Capra nubiana) can contribute to a more comprehensive understanding of their natural history, horn development in ibex in general, and future conservation of the species. Our specific objectives included (1) documenting age-horn growth patterns; (2) contrasting horn growth patterns of Nubian ibex with other ibex species; and (3) determining whether horn development accurately reflects age of Nubian ibex in Sinai, Egypt. As expected, all male and female horn measurements had significant relationships with age. Horn growth in males started plateauing at ca. age 7–8, whereas female horn growth started plateauing at ca. age 4–6. The extremely arid environment of Nubian ibex in the Sinai may account for the slowing of horn growth at a younger age than seen in populations of some other ibex species. We found a significant relationship between the number of horn ridges and age, indicating that counting horn ridges provides a viable method of aging males to within ±1 y. Thus counting horn ridges may be a useful and non-invasive method to determine age or age class, which can further our understanding of age structure, the natural history, and management of Nubian ibex populations.

Development of specific muscle and cutaneous sensory projections in cultured segments of spinal cord

Development ◽  
1994 ◽  
Vol 120 (5) ◽  
pp. 1315-1323 ◽  
Author(s):  
K. Sharma ◽  
Z. Korade ◽  
E. Frank
Keyword(s):  
Spinal Cord ◽  
Dorsal Horn ◽  
Muscle Afferents ◽  
Cutaneous Afferents ◽  
In Ovo ◽  
Sensory Afferents ◽  
Chicken Embryos ◽  
Sensory Projections ◽  
Spinal Segments ◽  
Horn Development

Development of sensory projections was studied in cultured spinal segments with attached dorsal root ganglia. In spinal segments from stage 30 (E6.5) and older chicken embryos, prelabeled muscle and cutaneous afferents established appropriate projections. Cutaneous afferents terminated solely within the dorsolateral laminae, whereas some muscle afferents (presumably Ia afferents) projected ventrally towards motoneurons. Development of appropriate projections suggests that sufficient cues are preserved in spinal segments to support the formation of modality-specific sensory projections. Further, because these projections developed in the absence of muscle or skin, these results show that the continued presence of peripheral targets is not required for the formation of specific central projections after stage 29 (E6.0). Development of the dorsal horn in cultured spinal segments was assessed using the dorsal midline as a marker. In ovo, this midline structure appears at stage 29. Lack of midline formation in stage 28 and 29 cultured spinal segments suggests that the development of the dorsal horn is arrested in this preparation. This is consistent with earlier reports suggesting that dorsal horn development may be dependent on factors outside the spinal cord. Because dorsal horn development is blocked in cultured spinal segments, this preparation makes it possible to study the consequences of premature ingrowth of sensory axons into the spinal cord. In chicken embryos sensory afferents reach the spinal cord at stage 25 (E4.5) but do not arborize within the gray matter until stage 30. During this period dorsal horn cells are still being generated. In spinal segments, only those segments that have developed a midline at the time of culture support the formation of midline at the time of culture support the formation of specific sensory projections.(ABSTRACT TRUNCATED AT 250 WORDS)

Microsatellite mapping of a gene affecting horn development in Bos taurus

1993 ◽  
Vol 4 (2) ◽  
pp. 206-210 ◽  
Author(s):  
Michel Georges ◽  
Roger Drinkwater ◽  
Tracey King ◽  
Anuradha Mishra ◽  
Stephen S. Moore ◽  
...  
Keyword(s):  
Bos Taurus ◽  
Microsatellite Mapping ◽  
Horn Development

scholarly journals Function of weaponry in females: the use of horns in intrasexual competition for resources in female Soay sheep

2007 ◽  
Vol 3 (6) ◽  
pp. 651-654 ◽  
Author(s):  
Matthew R Robinson ◽  
Loeske E.B Kruuk
Keyword(s):  
Local Density ◽  
Intrasexual Competition ◽  
Genetic Associations ◽  
Aggressive Interactions ◽  
Soay Sheep ◽  
Male Phenotype ◽  
Feral Population ◽  
Males And Females ◽  
Competition For Resources ◽  
Horn Development

In many species, females show reduced expression of a trait that is under sexual selection in males, and this expression is thought to be maintained through genetic associations with the male phenotype. However, there is also the potential for the female trait to convey an advantage in intrasexual conflicts over resources. We tested this hypothesis in a feral population of Soay sheep, in which males and females have a polymorphism for horn development, producing either full (normal horned), reduced (scurred) or no (polled, females only) horns. During the lambing period, females who possessed horns were more likely to initiate and win aggressive interactions, independent of age, weight and birthing status. The occurrence of aggression was also context dependent, decreasing over the lambing period and associated with local density. Our results demonstrate that a trait that confers benefits to males during intrasexual competition for mates may also be used by females in intrasexual competition over resources: males use weaponry to gain mates, whereas females use weaponry to gain food.

Comparison of a modified cryptorchid treatment and castration: effect on growth, wool production, posthitis, testosterone production and development of masculine characteristics

1992 ◽  
Vol 32 (4) ◽  
pp. 443 ◽  
Author(s):  
DL Hopkins ◽  
RB Jackson ◽  
AHK Roberts
Keyword(s):  
Rank Correlation ◽  
Asymmetric Distribution ◽  
Lower Prevalence ◽  
Blood Samples ◽  
Wool Production ◽  
Testosterone Levels ◽  
Testosterone Production ◽  
Testicular Size ◽  
Wool Quality ◽  
Horn Development

Male lambs born to Merino, Polwarth and Merino x Polwarth ewes were used to study a technique for manipulating testicular size. Of these lambs, 82 were castrated at marking (wethers). For the remaining 100 the testicular parenchyma was removed at marking and then, at a subsequent date, the scrotal sac and any large testicles were removed (modified cryptorchids). Cryptorchids were significantly (P<0.05) heavier than wethers throughout the study and produced significantly (P<0.05) heavier fleeces (4.3 � 0.08 v. 4.0 � 0.06 kg). Bin class, as an indicator of wool quality, was not significantly different between the 2 groups. At all times of the year, cryptorchids had a significantly lower prevalence (P<0.001) and severity of posthitis. Posthitis increased in spring and decreased in summer. There was significantly (P<0.001) more horn development in the cryptorchids, and Merino-sired animals had more horn development than those sired by Polwarth rams. The basal level of testosterone in the wethers was 0.08 � 0.07 ng/mL averaged over 3 successive blood samples, compared to the cryptorchids at 0.95 � 0.16 ng/mL with an asymmetric distribution. The rank correlation between average testosterone levels and testicle score was significant (P<0.05) with a coefficient of 0.54. The rank correlations between testosterone levels and fleeceweight, liveweight or horn score were not significant (P>0.05).

scholarly journals Is chamois hybridization in the northern Dinaric Mountains an important factor for horn development?

2018 ◽  
Vol 2018 (1) ◽  
Author(s):  
Krešimir Kavčić ◽  
Francesca Brivio ◽  
Stefano Grignolio ◽  
Damir Ugarković ◽  
Igor Stankić ◽  
...  
Keyword(s):  
Dinaric Mountains ◽  
Horn Development

Guide to field classification by sex and age of the muskox

1989 ◽  
Vol 67 (5) ◽  
pp. 1116-1119 ◽  
Author(s):  
Carsten Riis Olesen ◽  
Henning Thing
Keyword(s):  
Reliable Data ◽  
Age Classes ◽  
Successful Management ◽  
Ovibos Moschatus ◽  
Photographic Record ◽  
Age Class ◽  
Class Composition ◽  
Horn Development

Reliable data on sex–age class composition of muskox (Ovibos moschatus) herds are necessary prerequisites to any successful management initiative. The classification requires some training to be exact; this paper presents a photographic record and description of field characteristics of a total of eight different sex–age classes, thus enabling the observer to perform a correct herd segregation. Differentiation of muskoxen relies primarily on horn development and secondarily on body and pelage.

Behavioral and physiological assessment of liquid nitrogen cryoablation to prevent horn development in dairy calves

2019 ◽  
Vol 31 ◽  
pp. 74-81 ◽  
Author(s):  
Mhairi A. Sutherland ◽  
Suzanne K. Dowling ◽  
Karin E. Schütz ◽  
Vanessa M. Cave ◽  
Nikki J. Kells ◽  
...  
Keyword(s):  
Liquid Nitrogen ◽  
Dairy Calves ◽  
Physiological Assessment ◽  
Horn Development

scholarly journals Clove Oil Delays Rather Than Prevents Scur/Horn Growth in Dairy Cattle

2019 ◽  
Vol 6 (4) ◽  
pp. 102 ◽  
Author(s):  
Mhairi Sutherland ◽  
Alan Julian ◽  
Frances Huddart
Keyword(s):  
Dairy Cattle ◽  
Liquid Nitrogen ◽  
Dairy Calves ◽  
Structural Development ◽  
Clove Oil ◽  
Horn Growth ◽  
Horn Development

The objective of this study was to evaluate if administration of clove oil prevents scur/horn growth in dairy cattle long term. At approximately 4 days of age, calves had one of four treatments assigned to each horn bud: (1) clove oil administered subcutaneously under the horn bud (CLOV, n = 132); (2) cautery disbudded and the horn bud removed (BUDOFF, n = 126); (3) cautery disbudded and the horn bud tissue left intact (BUDON, n = 129); (4) a liquid nitrogen filled probe applied to the horn bud area (CRYO, n = 131). At approximately 16 months of age, all cattle were checked for scur or horn development. A sub-set of scurs/horns from the CLOV cattle were removed to evaluate tissue and structural development. In total, 5% of CLOV buds developed into horns and 63% into scurs; 10% of the scurs looked like normally developed horns but they were not attached to the skull. Cautery disbudding prevented scur and horn development in cattle when the horn bud tissue was removed, but some scur growth was observed in the BUDON treatment. CRYO was 100% ineffective at preventing scur/horn growth. Injecting clove oil under the horn bud appeared to delay horn development, but not prevent it, when administered to 4 day old dairy calves.

Sign in / Sign up

Export Citation Format

Share Document