Duration of protective immunity and antibody responses in cattle immunised against alcelaphine herpesvirus-1-induced malignant catarrhal fever

Table 1 Immunisation study groups, treatments and outcomes

Animal No.	Group	Vaccine/ Control^a	Challenge day^b	Day euthanized^c	Virus DNA in blood at PM	Pathology^dsummary	Days to clinical MCF
805	1	Vaccine	63	100	pos	MCF	37
789	1	Vaccine	63	103	pos	MCF	40
792	1	Vaccine	63	119	pos	MCF	56
568	1	Vaccine	63	139	neg	-
570	1	Vaccine	63	139	neg	-
785	1	Vaccine	63	140	neg	-
822	1	Vaccine	63	140	neg	-
807	1	Vaccine	63	140	neg	-
575	1	Control	63	84	pos	MCF	21
787	1	Control	63	93	pos	MCF	30
814	1	Control	63	96	pos	MCF	33
808	1	Control	63	103	pos	MCF	40
785	1	Control	63	103	pos	MCF	40
149	1	Control	63	107	pos	MCF	44
821	1	Control	63	116	pos	MCF	53
781	1	Control	63	128	pos	MCF	65
861	2	Vaccine	77	152	neg	-
702	2	Vaccine	77	152	neg	-
214	2	Vaccine	77	153	neg	-
774	2	Vaccine	77	153	neg	-
769	2	Vaccine	77	153	neg	-
090	2	Vaccine	77	154	neg	-
967	2	Vaccine	77	154	neg	-
968	2	Vaccine	77	154	neg	-
165	2	Control	77	110	pos	MCF	33
700	2	Control	77	152	neg	-
856	3	Vaccine	182	212	pos	MCF	30
776	3	Vaccine	182	217	pos	MCF	35
965	3	Vaccine	182	224	pos	MCF	42
701	3	Vaccine	182	257	pos	MCF	75
862	3	Vaccine	182	257	neg	non-specific
611	3	Vaccine	182	257	neg	non-specific
770	3	Vaccine	182	258	neg	-
699	3	Vaccine	182	258	neg	-
326	3	Control	182	217	pos	MCF	35
023	3	Control	182	250	pos	MCF	68
019	4	Vaccine	273	305	pos	MCF	32
969	4	Vaccine	273	310	pos	MCF	37
613	4	Vaccine	273	315	pos	MCF	42
771	4	Vaccine	273	320	pos	MCF	47
195	4	Vaccine	273	348	pos	MCF	75
966	4	Vaccine	273	348	neg	non-specific
768	4	Vaccine	273	349	neg	-
772	4	Vaccine	273	349	neg	-
719	4	Control	273	300	pos	MCF	27
620	4	Control	273	302	pos	MCF	29

^a Vaccinated animals in all groups received the same dose (10 mL of 10⁷ TCID₅₀ per mL) of vaccine for both prime and boost, given intramuscularly with 20% (v/v) Emulsigen. Control animals in each group received virus-free culture medium with Emulsigen, prepared and administered in the same way.
^b Pathogenic AlHV-1 challenge for each group was as follows: group 1 received 10 mL of 10^4.7 TCID₅₀/mL virus; group 2 received 10 mL of 10^3.8 TCID₅₀/mL virus; and groups 3 and 4 received 10 mL of 10^4.05 TCID₅₀/mL virus, administered intranasally in all groups.
^c All animals were monitored daily for clinical signs of MCF, including fever, loss of appetite, depression, nasal or ocular discharge and conjunctivitis. A clinical scoring scheme (Additional file 1 Table S 1) was used to ensure that all animals were euthanized at the onset of moderate clinical signs. Animal that did not develop clinical signs of MCF were euthanized for post-mortem at least 75 days after challenge. ^d Pathology was assessed as described in the text and is summarised as MCF, non-specific or negative (−). Tissue sections from animals with non-specific pathology were tested for presence of AlHV-1 DNA by real-time PCR. No viral DNA was detected in any sample with non-specific pathology.

ISSN: 1297-9716