Primordial germ cells (PGCs) are cells that will differentiate themselves into spermatogonia in the testis or oogonia in the ovary. Primordial germ cells arise from epiblast and circulate through the bloodstream and finally entering gonadal anlage. The aim of this study was to determine the number of gonadal PGCs of KUB chicken at different development stages. Sixty KUB chicken fertile eggs were divided into four groups (6, 7, 8, and 9 days incubation periods), and incubated at 38 o C with a humidity of 60%. Harvesting was synchronized to the embryonic development at 6-9 d. Gonads were collected using sharp tweezers, and were placed in Eppendorf tube 1.5 mL containing 500 µL PBS [-]. Gonadal PGCs were purified using PBS [-]. The results showed that the average number of gonadal PGCs at 6, 7, 8, and 9 d were 113.7; 143.5; 92.9; and 85.7 cells per embryo, respectively. Number of gonadal PGCs per embryo of KUB chicken were significantly affected by stage of embryonic development (P<0.05), which reached a peak at day 7 of incubation, so that the isolation and collection of PGCs from the gonads were recommended at day 7 of incubation. This information is useful in production of germline chimera of other Indonesian local chickens. Keywords

ABSTRAKSemen adalah cairan yang dikeluarkan oleh organ kelamin ternak jantan yang secara normal diejakulasikan ke dalam saluran reproduksi ternak betina melalui kopulasi. Evaluasi semen merupakan alat utama untuk memprediksi kinerja  reproduksi ternak ayam  jantan. Evaluasi kualitas semen penting dilakukan untuk menyelesaikan salah satu masalah utama dalam peternakan pembibitan ayam, yaitu   rendahnya fertilitas.  Faktor terbesar dari sumber masalah tersebut terkait dengan rendahnya kualitas semen ayam. Kualitas semen ayam  lebih banyak dipengaruhi oleh faktor non genetik, seperti faktor pakan dan nutrisi. Tujuan dari penulisan makalah ini adalah untuk mengkaji hasil-hasil studi terkait pengaruh pakan terhadap kualitas semen ayam. Hasil studi menunjukkan bahwa faktor pakan sangat mempengaruhi kualitas semen ayam, terutama imbangan energi metabolis-protein dalam pakan ayam jantan sangat penting diatur untuk menjaga berat badan ayam jantan agar tidak terjadi kelebihan atau kekurangan berat badan yang sangat mempengaruhi kualitas semen ayam. Suplementasi suplemen dan imbuhan pakan menjadi upaya yang dapat dilakukan untuk meningkatkan kualitas semen ayam. Jenis suplementasi yang dapat dilakukan dengan bahan sumber antioksidan, asam amino, mikromineral, bahan mengandung bioaktif tanaman, bahan sumber asam lemak dan probiotik. Disimpulkan bahwa faktor pakan sangat menentukan terhadap kualitas semen ayam.Kata kunci: ayam jantan, kualitas semen, pakanABSTRACTRooster semen is a liquid released by the genitals of the roosters which is normally ejaculated into the female reproductive tract during copulation. Semen evaluation is the main way to predict the reproductive performance of roosters. Semen quality evaluation is important to solve one of the main problems in poultry breeding farms, namely low fertility, whereas the biggest factor of this problem source is related to the poor of roosters’ semen quality. The quality of roosters semen is more influenced by non-genetic factors, such as feed and nutrition. The purpose of this paper was to examine the results of studies so far related to the effect of feed on the roosters’ semen quality. The results of the study indicated that the feed factor greatly influences the quality of roosters semen. The metabolic energy-protein balance in the rooster's feed was very important to regulate to maintain the weight of the rooster so as not to overweight and underweight because bodyweight greatly affects the quality of roosters semen. Supplementation of feed supplements and feed additives was an effort that can be done to improve the roosters semen quality. The kind of supplementation that could be done was supplementation of antioxidant sources, amino acids, microminerals, materials containing plant bioactive, fatty acid source ingredients, and probiotics. It was concluded that the feed factor was crucial to the quality of semen quality produced by the roosters.Keywords: feed, rooster, semen quality

The research objective was to determine the weight and hatchability of quail eggs which were influenced by the weight, index, and surface area of the eggs. Quail eggs were obtained from Slamet Quail Farm, Sukabumi. The experimental design used was CRD. The treatments consisted of 3 categories, namely light egg weight (≤11.20 g), medium (11.21–13.06 g), and heavy (≥13.07 g); oval egg shape index (≤74.72), normal (74.73–84.04), and round (≥84.05); and the surface area of eggs is narrow (≤89.22 cm2), medium (89.23–95.88 cm2), and large (≥95.89 cm2). The data obtained were analyzed with GLM SPSS 22. If it shows a significant difference, then proceed with the Duncan test. The analysis showed that egg weight had an effect on the weight and hatchability (P<0.05), while the egg index had no effect on the weight and hatchability (P>0.05). While the large surface area affects the weight and hatchability (P<0.05), while the narrow and medium surface area does not affect the weight and hatchability (P>0.05). It can be concluded that the weight and hatchability of quail eggs are influenced by egg weight and large surface area, but not by egg index and narrow and medium surface area.

Gonadal development is a sequential process that can be divided into three major events: the PGCs migration, sex determination and gonadal differentiation. This study was aimed to see the development of PGCs isolated from the gonads of embryos after being incubated for 7 days and then was incubated using a solution of Phosphate Buffer Saline (PBS) [-]. The developing gonad can be isolated from 7 days old chick and can be incubated at a temperature of 37.8^oC in a solution of PBS [-]: without Ca2+ and Mg2+. The release of gonadal PGC was observed within 1, 8, 16, and 24 hours after the embryonic gonad was placed in a PBS solution [-]. The results showed that PGCs can be separated from gonadal tissues and can be collected by entering the developing gonad to the PBS [-] solution. The highest percentage of PGCs and survival rate was obtained after gonad was incubated for 1 hour and was not different with 8 hours (P&gt;0.05). Those result was significantly different (P&lt;0.05) with the 16 and 24 hours incubation. The highest purity rate percentage was in the 8 hours incubation, but did not show a significant difference (P&gt;0.05) with the 1 and 16 hours incubation. The percentage of the purity differed (P&lt;0.05) after the 24 hours incubation. It can be concluded that the most appropriate incubation time to obtain PGCs from the KUB chicken embryonic gonad is no more than 8 hours.

<p class="abstrak2">In poultry embryos, primordial germ cells (PGCs) are progenitor cells for gametes, which have unique migration pathway. Primordial germ cells arise from epiblast in germinal crescent and circulate through the bloodstream for a short period of time, then leave blood vessel to migrate toward gonads. The aim of this study was to determine the potential production capacity of circulated-PGCs of KUB chicken at different developmental stages of embryo using a rapid and simple method. Seventy five KUB chicken fertile eggs were divided into five groups and incubated at 38.5 ⁰C with a humidity of 60%. Hatching was set to the embryonic development stage of 14-18. The blood was collected through dorsal aorta using micropipette under microscope. The collected blood was placed in a 1.5 ml eppendorf tube which was previously filled with 100 µl phosphate buffered saline without Ca²⁺ and Mg²⁺ (PBS-) mixed with fetal bovine serum (FBS) with a ratio of 90%:10%. The PGCs were purified using lysis buffer ammonium chloride potassium method. The results showed that average production of circulated-PGCs per embryo of KUB chicken were significantly affected by stage of embryonic development (P &lt;0.05). The average production of circulated-PGCs at stage 14, 15, 16, 17, and 18 were 37.9; 53.5; 49.8; 38.3; and 33.5 respectively. The number of circulated-PGCs was not different among stages 14, 17 nor 18. The highest number of circulated-PGCs of KUB chicken was obtained at stage 15, so that the isolation and collection of PGCs through the blood circulation was recommended in stage 15.</p><strong>Key Words: </strong>KUB Chicken, PGCs, Embryonic Development Stage, Ammonium Chloride Potassium

Evaluation of egg quality characteristics and influencing factors are very important to note. One of the factors that affect the quality of the egg is the breed of chicken. The research objective was to compare some parameters of egg quality between White Leghorn (WL) and Naked Neck chicken. Number of eggs collected were 49 eggs from WL and 59 eggs from Naked Neck. All variable egg quality was measured using an egg multi tester EMT-5200. For egg white grading, it was used the standards of the USDA (grade AA, A, and B). The average of egg weight was significantly (P<0.05) influenced by the breeds. Thickness of eggshell were significantly different (P<0.05) between WL and Naked Neck chicken (0.46±0.05 vs 0.43±0.04 mm). Haugh units (HU) were significantly higher in WL (67.64±9.97) compared with Naked Neck chicken (57.62±11.69). The percentage of the characteristics of the egg white on a WL chicken more on grade A (47.68%) while the Naked Neck chicken on grade B (59.18%). More yolk color WL chicken on score 4 (52.54%) and Naked Neck chicken on score 5 (48.98%). It can be concluded that, egg weight, eggshell thickness, HU, and the percentage of egg white on WL chicken showed superior than Naked Neck chicken.

ABSTRAK. Fertilitas dan daya tetas sangat penting secara ekonomi untuk semua tempat penetasan, oleh karena itu harus diberikan perhatian khusus. Tujuan dari penelitian adalah untuk mengetahui pengaruh ukuran bobot telur terhadap persentase fertilitas dan daya tetas ayam Cemani dan White Leghorn. Telur tetas (299) dari ayam Cemani dan White Leghorn diperoleh dari kompleks kandang Balitnak dan dibagi menjadi 3 kategori ukuran bobot telur (kecil, sedang, dan besar). Data bobot telur tetas, fertilitas, dan daya tetas dianalisis berdasarkan Rancangan Acak Kelompok pola faktorial 3 x 2. Faktor pertama adalah ukuran bobot telur dan faktor kedua adalah jenis ternak, menggunakan prosedur General Linear Model dari SPSS versi 22. Jika terdapat pengaruh, maka diuji lanjut dengan uji Duncan. Sementara itu, untuk mengetahui hubungan antara ukuran bobot telur terhadap fertilitas dan daya tetas dihitung dengan persamaan regresi. Penelitian menunjukkan ukuran bobot telur secara signifikan (P0,05) memengaruhi bobot telur tetas, fertilitas, dan daya tetas. Telur ukuran sedang memberikan persentase fertilitas dan daya tetas yang lebih baik dibandingkan dengan telur ukuran kecil dan besar. Begitu juga untuk persamaan regresi memperlihatkan ada korelasi positif antara ukuran bobot telur terhadap fertilitas dan daya tetas, di mana ukuran bobot telur sedang mempunyai nilai R tertinggi. Pemilihan telur ukuran sedang akan bermanfaat untuk memaksimalkan persentase fertilitas dan daya tetas. (Percentage of fertility and hatchability of cemani and white leghorn chickens based on size of egg weight) ABSTRACT. Special attention to the trait of fertility and hatchability is very important because these two characteristics have economic value in all hatcheries. The purpose of this study was to determine the effect of egg weight size to the fertility and hatchability percentage in Cemani and White Leghorn chickens. The sample used in this research was the hatching eggs of Cemani and White Leghorn chickens (299 eggs) that obtained from the Balitnak chicken station. The eggs are divided into 3 egg weight size categories (small, medium and large). Data on weight of hatching egg, fertility, and hatchability were analyzed based on a 3 x 2 factorial randomized block design. The first factor was egg weight size and the second factor was breed. Data analysis used the General Linear Model procedure from SPSS version 22. If the effect is significantly different, then Duncan's test will be continued. Meanwhile, the correlation between size of egg weight and fertility is analyzed by regression. The results showed that the size of the egg weight was significantly (P0.05) on the hatching egg weight, fertility, and hatchability. The best percentage of fertility and hatchability is eggs in the medium category. Fertility and hatchability of eggs have a positive correlation with egg weight measurements, where the measurement of egg weight in the medium category has the highest R value. The choice of medium size eggs will be beneficial to maximize the percentage of fertility and hatchability.

ABSTRAK. Ayam Gaok merupakan salah satu rumpun ayam lokal yang memiliki potensi besar dikembangkan. Balai Penelitian Ternak (Balitnak) telah melakukan program seleksi pada ayam Gaok untuk menghasilkan bibit ayam lokal pedaging yang dipanen umur 10 minggu dan dapat dijadikan galur jantan (male line) yang akan disilangkan dengan ayam KUB yang merupakan galur betina (female line). Tujuan dari penelitian ini untuk mengetahui pertumbuhan bobot badan dan karakteristik semen ayam Gaok generasi ke-6 yang dipelihara di Balitnak. Sebanyak 211 ekor anak ayam Gaok umur satu hari dari generasi ke-6 dipelihara pada kandang koloni pada masa starter dan grower. Ayam dewasa dipelihara pada kandang individu. Pakan dan air minum diberikan ad libitum. Bobot badan ayam jantan dan betina pada umur 10 minggu masing-masing 1.075,26 ± 156,55 g (KK= 14,56 %) dan 868,25 ± 109,34 g (KK= 12,59 %). Rerata bobot badan jantan dan betina sudah mulai berbeda nyata (P0,05) pada saat ayam berumur lima minggu. Konsumsi dan konversi pakan sampai umur 10 minggu yakni masing-masing 2.801,61 g dan 2,99. Bobot badan ayam jantan dan betina pada umur 20 minggu masing-masing 2.354,01 ± 280,06 (KK= 11,90%) dan 1.646,5 ± 205,97 g (KK= 12,51%). Volume semen, konsentrasi, motilitas dan persentase sperma hidup ayam Gaok jantan pada umur delapan bulan masing-masing sebesar 0,4 ml, 3.927 × 106, 57,22 dan 62,5%. Bobot badan ayam Gaok umur 10 minggu menunjukkan hasil baik dengan variasi yang cukup seragam. Kuantitas dan kualitas semen ayam Gaok tergolong normal.  (Analysis of body weight and semen characteristic of 6th generation selected gaok chicken) ABSTRACT. Gaok chicken is one of local breed chicken which potentially to be developed. Indonesian Research Institute for Animal Production (IRIAP) have been executed selection program on Gaok chicken to obtain meat type local chicken which is harvested on 10 weeks old age and can be made as male line to be crossed with KUB chicken which is the female line. The objective of this study was to observe growth of body weight and characteristics of semen of Gaok chicken 6th generation which are raised in IRIAP. A number of 211 DOC Gaok chicken 6th generation were raised in colony cage in starter and grower periods. Mature chickens were kept in individual cages. Feed and water were given ad libitum. Body weight male and female at 10 weeks were 1,075.26 ±156.55 g (CV=14,56 %) and 868.25 ± 109.34 g (CV=12,59 %) respectively. Body weight on male and female were started significantly differ from five weeks (P0.05). Feed consumption and conversion for 10 weeks were 2,901.61 g and 2.99, respectively. Body weight male and female at 20 weeks were 2,354.01 ± 280.06 g (CV=11,90 %) and 1,646.5 ± 205.97 g (CV=12,51 %) respectively. Semen volume, concentration, motility and proportion of live sperm of male Gaok chicken were 0.4 ml, 3,927 × 106, 57,22 % and 62.5 %, respectively. 10th week body weight of Gaok chicken showed good results with uniform variation. Quantity and quality of Gaok chicken semen belonged to be normal.