Short-term effect of foot-and-mouth disease (FMD) vaccination on the milk yield in the Deoni and crossbred cows.

Biannual vaccination of the cattle with inactivated foot-and-mouth disease (FMD) vaccine is the control strategy in endemic countries. Reduction in the milk yield is one of the main reasons for poor compliance of the cattle owners to FMD vaccination. As it can adversely affect the herd immunity, the present study aimed to quantify the losses in the milk yield post-FMD vaccination. Retrospective data on the milk yield (kg) recordings, days in milk, parity, and age at vaccination of the Deoni and crossbred cows were collected from 10 days before (-10) to 10 days after (+10) FMD vaccination (dpv). Days in milk were categorized into three stages of lactation for Deoni and crossbred cows. Age (month) was categorized into four classes. Least squares means of the milk yield were generated after adjusting for year, age, parity, and stage of lactation. Based on exploratory data analysis, the corrected milk yield records from -2 to +2 dpv for 5 years comprising 614 data points on Deoni cows (n=54) and 488 data points on crossbred cows (n=55) were used for the final analysis. Because of the correlated errors on the corrected milk yield, linear mixed model ANOVA was done by fitting dpv as fixed effect and cow as random effect, and the results revealed the effect of dpv was non-significant (P>0.05) in either breed. With respect to dpv 0, a marginal reduction of 90 g in the corrected milk yield in the Deoni cow was recorded on dpv 1, while the reduction was about 360 g on dpv 0 as compared dpv -1 in the crossbred cow. It was concluded that FMD vaccination caused a transient non-significant reduction in the milk yield in the Deoni and crossbred cows.

Evaluation of feeding different forms of therapeutic diet on the feed intake, digestibility, feed efficiency, and growth of calves experimentally infected with foot-mouth disease virus.

Oral ulcers induce acute weight loss due to anorexia in foot-and-mouth disease virus (FMDV) infected cattle. We hypothesized that providing a palatable form of a therapeutic diet (TD) in different physical forms would increase the feed intake, digestibility and restoration of body weight. A TD was formulated with 19% CP and 2.9 Mcal ME/kg on dry matter basis. Bull calves of 10-12 months with mean body weight of 123 ± 1.3 kg were experimentally infected with FMDV (n = 18) and offered one of the following three forms of the TD (n = 6/group) for 6 weeks post-FMDV infection (WPI): (i) TD in mash form (TDM) (ii) TD in cooked form (TDC) and (iii) TDC + customised nutrient supplement (TDCNS) such as Zn, Cu, Cr, Mn, and Se. The CNS was fed before the TDC. A group of uninfected control (n = 4) was fed TDM. Green fodder was offered in the afternoon. Dry matter intake (DMI) of TD and green fodder were recorded at 24 h interval till WPI 6. Body weight (BW) was recorded at weekly interval. Digestibility trial was conducted at WPI 6. The palatability of the TD was scored from 1- 4 and healing of tongue ulcers was analyzed by Kaplan-Meier survival curve. The results indicated that the physical form of TD increased the total DMI by WPI 3, which was supported by the restoration of BW and higher palatability score. The digestibility of all the proximate principles except EE was significantly higher (P < 0.05) in the groups that were fed TDC. It was concluded that feeding TD irrespective of the physical form, restored the ADG and DMI in the calves by WPI 3. Further, feeding cooked form of TD increased the digestibility in the FMDV infected calves and supplementation of CNS hastened the healing of glossal ulcers.

Effect of physical form of the therapeutic diet on the behaviour of crossbred calves experimentally infected with foot-and-mouth disease virus.

The oral lesions associated with foot-and-mouth disease (FMD) negatively affect animal behavior, which can adversely impact animal production and welfare. Physical form of a therapeutic diet (TD) can improve the feed intake and wellbeing during the acute phase of FMD. Accordingly, we tested the effect of two physical forms of a previously developed TD on the behavior of calves experimentally infected with FMD virus (FMDV). Crossbred Holstein Friesian male calves of 10-12 months (n = 12) were experimentally infected with a virulent strain of FMDV and were offered a TD enriched with 19% CP and 2.9 Mcal ME/kg for 11 days post-FMDV infection. One group received the TD in mash form (TDM) while the other (n = 6/group) received it in cooked form (TDC). A group of four calves served as uninfected control and were fed TDM. The time spent by the calves on certain behaviours was recorded in a pre-set form from 06:00-18:00 h for 10 days from day 2-11 post-FMDV infection. The data was divided into two sessions. Session 1 (06:00-13:00 h) represented after the offering of TD, while session 2 (13:01-18:00 h) represented the data after offering green fodder. Based on exploratory data analysis, data recorded from day 2-7 post-FMDV infection was included in the final analysis. Linear mixed model was used by fitting treatment, day and their interaction as fixed effects while calf as random effect. Orthogonal contrast was applied by comparing the infected TDM with other two groups. The results revealed that the cooked form of TD improved the ingestion time, resting time, sleeping time and licking time from day 2-7 post-FMDV infection as compared with the infected TDM group. Ingestive behaviour was better in the infected TDC than that of TDM group (p < 0.01). The sleeping time was significantly high in the infected groups as compared to the uninfected TDM group (p < 0.01) till day 6 post-FMDV infection. Daily activities such as licking, standing and resting differed significantly between the infected TDM and TDC groups in session 1, but not in session 2. Urination and defecation did not differ significantly between the infected TDM and TDC groups. It was concluded that cooked form of TD remediated the effects of infection with FMDV as evidenced by improvement in the behaviour of the calves.