Improving stress coping ability: comparison between the CYP17 genotype Of Ovis Aries and Capra Hircus

The ability of animals to adapt to stress is not only an animal health and welfare concern, but also influences reproduction potential and robustness. An important pathway involved in the stress response is the hypothalamic-pituitary-adrenal axis (HPAA) that results in the release of cortisol from the adrenal gland. In this study the cortisol responses of South African Merinos were measured to assess HPAA responsiveness to stress and relate it to behavioural stress responses to flock-isolation. The experiment was structured according to a 2×2 statistical design, with CYP17 genotype (WT1/WT1 vs. WT1/WT2) and selection line (H-line vs. L-line) as factors. Selection line criteria was based on divergent selection for (H-line) or against (L-line) maternal multiple rearing ability, where the H-line generally outperformed the L-line in terms of reproduction, animal welfare and resistance to certain pathogens. The CYP17 genotype is involved in the biosynthesis pathway of cortisol. In the present study the CYP17 genotype showed a significant influence on behavioural stress responses, where three parameters of the flock-isolation test were affected (P<0.05), namely the number of bleats uttered, the urinating frequency and the average distance from a human operator. It is suggested that the CYP17 genotype affects behavioural responses via its effects on cortisol production, and that the SNPs located within the CYP17 genotype may have application in marker-assisted selection of sheep

The role of Cytochrome P450 17-alpha-Hydroxylase/ 17,20-Lyase (CYP17) in the stress coping ability in a divergently selected Merino sheep population

South African Merino sheep were selected divergently from the same base population for their ability to rear multiples. Two distinct populations were formed over a period of more than 20 years of selection. Reproduction (and therefore presumably fitness) in the line selected in the upward direction (H-line) was substantially improved compared to the line selected in the downward direction (L-line). In the present study, it was demonstrated that the H-line was more stresstolerant than the L-line in terms of their glucose and cortisol response when challenged with insulin. Sheep from the breeding program were genotyped according to one of two cytochrome P450 17α-hydroxylase/17-20 lyase (CYP17) alleles, as these genotypes were previously linked to the ability of Angora goats to cope with external stressors. However, no association was found between CYP17 genotype and selection line. The difference in insulin induced stress response between the H- and the L-line can therefore not be attributed to CYP17 genotype

Hatch traits of artificially incubated ostrich eggs as affected by setting position, angle of rotation and season

High levels of hatching failure in artificially incubated ostrich eggs cause considerable loss of income for the industry. In the 2015 - 2016 breeding seasons, between 846 and 1 549 egg records were used to determine the effect of various setting positions during artificial incubation. Fresh eggs were placed in trolleys in the setter that were turned automatically hourly through 60 degrees or 90 degrees. The additional treatments as factorial design included eggs set horizontally for five weeks in the setter; in horizontal position for three weeks and vertically for two weeks; and vertically for five weeks. These treatments were repeated over two production years to represent the seasons, namely winter (June to August), spring (September to November), and summer (December). Late embryonic mortalities improved significantly in eggs that were set to turn through 90 degrees (0.16 ± 0.02) compared with those set to turn through 60 degrees (0.28 ± 0.02), regardless of season and setting position. The preferred way of setting ostrich eggs would therefore be vertically in a trolley that turns hourly through 90 degrees with the air cell upwards to utilize incubator space optimally

Environmental and genetic aspects of survival and early liveweight in Western Australian Merino sheep

(Co)variance estimates for birth weight, pre-weaning lamb survival and weaning weight were obtained for Merino lambs derived from 16 bloodlines. Between bloodline variance ratios (± s.e.) amounted to 0.10 ± 0.04 for lamb birth weight, 0.053 ± 0.036 for lamb survival (logit scale) and 0.18 ± 0.07 for lamb weaning weight. Direct additive genetic variances for weaning weight - expressed as a ratio of the total phenotypic variance within bloodlines (h2, direct heritability) - were estimated at 0.18 ± 0.02 for birth weight, 0.094 ± 0.020 (logit scale) for pre-weaning survival and 0.30 ± 0.02 for weaning weight. Corresponding maternal genetic variance ratios (m2) were estimated at 0.15 ± 0.02 for birth weight and 0.08 ± 0.02 for weaning weight. It was not significant in the case of lamb survival. Maternal permanent environmental variance ratios (c2) amounted to 0.08 ± 0.02 for birth weight, 0.044 ± 0.018 for lamb survival (logit scale) and 0.07 ± 0.02 for weaning weight. These results were discussed with reference to sheep production. (South African Journal of Animal Science, 2001, 31(2): 123-130

The effects of shade and shearing date on the production of Merino sheep in the Swartland region of South Africa

A total of 497 Merino ewes were allocated to one of four experimental groups for the period 1996 to 1998. The treatments were designed to provide data on the effect of shade during an autumn lambing season and the effect of shearing prior to joining in September or prior to lambing in February. Dietary intake in shaded and control paddocks was similar, but animals in shaded paddocks consumed less water than those in control paddocks. Lambs born in shaded paddocks tended to be heavier at birth than those born in control paddocks. Survival of lambs was unaffected by the provision of shade, but lambs born in shaded paddocks were 3.8 % heavier at weaning than contemporaries born in control paddocks. Lambs born to ewes that were shorn prior to lambing tended to be lighter than those from ewes shorn prior to joining. Lamb survival prior to weaning tended to be higher in lambs born to ewes shorn prior to lambing than in those shorn prior to joining. Shearing of ewes prior to lambing had a beneficial effect on lamb survival during 1997, when the survival of progeny of ewes shorn prior to joining was low. Annual lamb survival data obtained in the present experiment were combined with that from two previous experiments conducted at the same site. The response in lamb survival of the progeny of ewes shorn prior to lambing depended on the average lamb survival observed in the control group. Multiple-born progeny of ewes shorn prior to lambing grew faster to lamb marking than contemporaries born to ewes shorn prior to joining. No difference was detected in single lambs. The clean fleece weight of ewes shorn prior to lambing was heavier than that of contemporaries shorn prior to joining. Similar benefits were found for staple strength and the frequency of mid-staple breaks. It was concluded that the shearing of ewes prior to lambing might be advantageous under certain conditions, particularly when lamb survival is likely to be low. (South African Journal of Animal Science, 2000, 30(3): 164-171

Faecal nematode egg counts in Merino sheep following natural challenge

(South African J of Animal Science, 2000, 30, Supplement 1: 24-25

LAPORAN INDIVIDU KEGIATAN PRAKTIK PENGALAMAN LAPANGAN (PPL)

Praktik Pengalaman Lapangan (PPL) merupakan kesempatan bagi mahasiswa yang bertujuan untuk mengembangkan kompetensi mahasiswa dalam membentuk calon guru atau tenaga kependidikan yang profesional. Kegiatan utama yang dilakukan dalam Praktik Pengalaman Lapangan (PPL) adalah mengajar secara terbimbing. Sebelum melakukan kegiatan mengajar terbimbing, perlu dilakukan persiapan, seperti: (1) pembuatan RPP, (2) media pembelajaran dan (3) penggunaan metode yang sesuai dengan karakteristik siswa sesuai dengan hasil observasi sebelumnya. PPL dilaksanakan di SMP Negeri 2 Mlati mulai tanggal 15 Juli sampai dengan 15 September 2016. Kegiatan PPL di SMP Negeri 2 Mlati tahun ajaran 2016/2017 memperoleh hasil sebagai berikut: (1) PPL dilaksanakan di kelas VII A dengan jumlah siswa 32 anak, (2) Kegiatan belajar mengajar berlangsung sebanyak 12 pertemuan, (3) proses belajar mengajar yang dilaksanakan di kelas berjalan dengan lancar terbukti melalui hasil analisis evaluasi yang menunjukkan ketercapaian ketuntasan sebanyak 59%. Diharapkan dari proses pembelajaran selama kegiatn PPL ini dapat dijadikan pengalaman guna menambah bekal bagi mahasiswa PPL untuk menjadi calon guru yang profesional yang merupakan tujuan dari kegiatan PPL

Improving stress coping ability: comparison between the CYP17 genotype Of Ovis Aries and Capra Hircus

The ability of animals to adapt to stress is not only an animal health and welfare concern, but also influences reproduction potential and robustness. An important pathway involved in the stress response is the hypothalamic-pituitary-adrenal axis (HPAA) that results in the release of cortisol from the adrenal gland. In this study the cortisol responses of South African Merinos were measured to assess HPAA responsiveness to stress and relate it to behavioural stress responses to flock-isolation. The experiment was structured according to a 2×2 statistical design, with CYP17 genotype (WT1/WT1 vs. WT1/WT2) and selection line (H-line vs. L-line) as factors. Selection line criteria was based on divergent selection for (H-line) or against (L-line) maternal multiple rearing ability, where the H-line generally outperformed the L-line in terms of reproduction, animal welfare and resistance to certain pathogens. The CYP17 genotype is involved in the biosynthesis pathway of cortisol. In the present study the CYP17 genotype showed a significant influence on behavioural stress responses, where three parameters of the flock-isolation test were affected (P<0.05), namely the number of bleats uttered, the urinating frequency and the average distance from a human operator. It is suggested that the CYP17 genotype affects behavioural responses via its effects on cortisol production, and that the SNPs located within the CYP17 genotype may have application in marker-assisted selection of sheep