- Esb3 (hang Novatis, Thuy Sy san xua't): thanh phan chfnh la Sulfachlozine sodium monohydrate (30%).
11. Ldp vo ngoai (Outer layer of Oocyst wall)
1.3. Chu ky sinh hoc cua cau trung Ion
Vong ddi cua cau trung dupe tfnh tu khi gia sue nuot phai noan nang co sure gay benh, qua qua trinh sinh truong, phat trien trong va ngoai co the cho den khi chung lai tao ra nhung noan nang co sure gay benh.
Sir luu truyen rong khap cua cau trung tren hanh tinh cua chung ta la nhd vao ca'u true va vong ddi phuc tap cung nhu kha nang thfch nghi nhanh de tiep tuc phat trien, ton tai lau trong thien nhien (Le Van Nam, 2003).
Chu trinh phat trien sinh hoc cua cac loai cau trung Ion gidng nhu d cac loai dong vat khac.
1.3.1. Chu ky sinh hoc ciia cau triing giong Eimeria
Cau triing sinh san theo 3 giai doan:
+ Giai doan sinh san vo ti'nh (Schyzogonie)
+ Giai doan sinh san huu tinh (Gametogonie)
+ Giai doan sinh san bao tir (Sporogonie)
Hai giai doan dau tien hanh trong co the ky chii nen goi la thdi ky noi sinh san. Thdi ky noi sinh san didn ra trong te bao bieu bi ruot gia sue (Kolapxki N.A. va cs, 1980). Giai doan sau tien hanh ngoai co the ky chii nen goi la thdi ky ngoai sinh san. Cu thd nhu sau:
Lem nudt Oocyst cd sure gay benh, vao d£n da <%, dudi tic ddng cua dich da day.
Oocyst vd ra, giai phong 4 Sporocyst. D6n rudt non, cac Sporozoit bdn trong Sporocysl
duoc hoat hoa bdi dich mat va men Trypsin, chung tro nfen hoat ddng, pha vd ldp mang
cua Sporocyst va duoc giai phong ra. Lip turc, Sporozoit xftm nhap t£ bao bidu md rudt
va tidn hanh sinh san vd tinh. Chung ldn len ra't nhanh, hinh trdn hoac hinh bau due, phan chia theo hinh thuc liet phan thanh nhieu thd phan lip the he 1 (Schizont 1).
Ngay ben trong thd phan lap the he 1 do, xung quanh mdi nhan, cac nguyen sinh chat xua't hien va bao quanh dd hinh thanh dang ky sinh trung nhd hinh bau due, luc niy chung duoc goi ia thd phan lap trung gian (Merozoit). Thd phan lap trung gian phat tridn, chung pha tung te bao bidu bi noi chung khu tru va giai phdng ra rSft nhidu Merozoit
trudng thanh. Cac Merozoit lai lap turc xam nhap vao cac te bao bidu bi mdi dd tiep tuc phat tridn va trd thanh the phan lap the' he mdi, goi la Schizont 2. Qua trinh sinh san v6 tinh cur nhu vay, ducrc lap di lap lai nhidu l£n va tao ra thd phan lap the he 3,4,5,...
M6i chung ciu trung khac nhau co giai doan sinh san v6 tmh khac nhau, hinh thanh n6n cac thd phan lap va sd the' he thd phan lap nha't dinh khac nhau, sau dd chung chuydn sang giai doan sinh san huu tfnh.
- Giai doan sinh san hiru tmh (Gametogonie):
Giai doan sinh san huu tinh bat d£u tir thd phan lap the' he cudi cung cua c£u triing. Tir thd phan lap cuoi cung, chung phan chia thanh cac the phan doan va xam nhap vao cac te' bao bidu bi ky chu de bien thanh nhung the sinh dudng va phat trien thanh cac giao tir due, giao tir cai. Giao tu cai (Macrogamet/Macrogametocyte), co nhan ra't to, chura nhidu chat dinh dudng, ft chuyen d6ng va co 16 noan. Giao tu due
(Microgamet/Microgametocyte) nho hem, nhan cua no cung nho hern, chung chuydn
d6ng nhanh nhd co 2 l6ng roi. Qua Id noan (Micropyle)cua giao tu cai, giao tu due chui vao va thuc hien qua trinh thu tinh tao ra hop tu. Hop tir duoc bao boc bdi mot ldp mang boc, luc nay no duoc goi la noan nang (Oocyst). Noan nang hay nang trung cd hinh b£u due, gan tron, elip hay qua le (phu thuoc vao tung loai cau trung). Den day, cac Oocyst
roi vao long ruot va ket thuc giai doan sinh san huu tfnh.
Mang vo boc nang trung gom 2 ldp, nguyen sinh chat luon d dang hat. 0 mot sd loai cau trung thay d mot dau Oocyst co ca nap trung, 16 noan, diem sang hay hat cue. Nhu vay, tuy tung chung cau trung ma co hinh dang, kfch thudc noan nang khac nhau, co hay khong co nap trumg, 16 noan, diem sang hay hat cue, cung nhu giai doan sinh san bao tir hinh thanh bao tir hay tui bao tir, co hay khong co the can trong noan nang hay trong bao tir.
- Giai doan sinh san bao tir (Sporogonie):
Sau khi Oocyst rcrj vao long ruot, chung ciing vdi phan ducrc thai ra ngoai moi trudng va bat dau giai doan phat trien mdi ngoai co the.
Theo Bhurtei J. E. (1995), co tir 70 - 80% Oocyst thai ra vao ban ngay, tap trung khoang thdi gian tir 9 gid sang den 13 gid chieu, mac du luc nay chi co 25% luong phan trong ngay duoc thai ra.
Trong dieu kien thien nhien khac nghiet hoan toan khac vdi moi trucmg ben trong co the ky chu, cac noan nang mutfn tiep tuc duy tri dupe su sdng buoc phai thich nghi vPi dieu kien mPi, trong do nhiet dd, dd dm, anh sang, khong khi... luon thay ddi. Nang trumg tu bao ve bang cach nhanh chdng tao ra vo cung, day g6m 1 - 2 lap vdi mau s k khac nhau tuy thuoc vao chung c£u trung. Sau do, trong m6i nang trung hinh thanh 4 nguyen bao tu co hinh bau due, xung quanh mdi nguyen bao tu lai dupe bao boc mdt lop mang mong va tro thanh tui bao tir (Sporocyst) Trong m6i tui bao tu, nhan ciia te bao lai chia doi ve hai phia, dupe ngan each bdi mot mang mong nua de trd thanh the’ bao tir co hinh ludi liem goi la bao tir con (Sporozoit).
Nhu vfiy, trong qua trinh sinh san bao tir, ddi vdi cau trung thuoc gidng Eimeria tir m6i nang trumg (Oocyst) hay con goi la noan nang tao ra 4 tien bao tir (Sporocyst), trong m6i tien bao tu lai chua 2 the bao tu (Sporozoit). Tat ca 8 the bao tir dupe bao boc xung quanh bdi mot vo cung day gom 2 ldp goi la bao tu nang (Oocyst gay benh). Ket thuc giai doan 3 cua qua trinh phat trien c£u triing hay ket thuc giai doan sinh san bao tir. Chi co cac Oocyst sau khi trd thanh Oocyst gay benh mdi co kha nang gay benh va truyen benh tir gia sue nay sang gia sue khac. (Kolapxki N.A va cs, 1980).
1.3.2. Chu ky sinh hoc cua cau trung giong Isospora
Vong ddi cua c iu triing gidng Isospora cung tuong tu nhu gidng Eimeria, chi khac d giai doan 3 - giai doan sinh san bao tir (Sporogonie) d ngoai co the. Trong
mdi Oocyst chi hinh thanh 2 tui bao tir (Sporocyst) chu khong phai la 4 tui bao tir
nhu gidng Eimeria. Nhung trong m6i tui bao tir lai hinh thanh 4 the bao tir
{Sporozoit), va tat ca duoc boc chung trong vo cung gom 2 ldp goi la bao tir nang
(Oocyst gay benh). Nhu vay, ket thuc giai doan sinh san bao tir cua cau triing gidng
Isospora cung tao ra bao tir nang (Oocyst gSy benh) g6m 8 the bao tir (Sporozoit)
gidng nhu Eimeria.
Giong Eimeria Giong Isospora
Sin in h sa n ba o tC r (* * % ,
Hinh 133. Oocyst mcri theo phan ra ngoai
Hinh 134. Phdi bao cua Oocyst dang co lai Hinh 135. Oocyst co site gay benh
de hinh thanh tui bao tu(ngay thu 5 trong
lap ddt be mat) ( t M 10 tronS ldP ^ b i