The effect of parenteral vitamin B₁₂ on the growth rate of dairy calves over the summer and autumn on seven farms from the Central Plateau, New Zealand

Figures & data

Table 1. Summary of the supply of oral cobalt from the use of mineralised anthelmintics on seven farms from the Central Plateau area of New Zealand during a trial investigating the effect of vitamin B₁₂ injection on the growth of dairy calves at pasture.

Farms	Anthelmintic	Manufacturer	Dose rate	Cobalt dose rate
1, 4	Switch C Hi-mineral	Boehringer Ingelheim	1 mL/20 kg	0.44 mg/kg
3, 5, 6, 7	Matrix C Hi Mineral	Boehringer Ingelheim	1 mL/10 kg	0.44 mg/kg
2	Scanda Selenised	MSD Animal Health	1 mL/10 kg	0.04 mg/kg

Table 2. Summary of farm type, enrolment dates and trial events for seven farms from the Central Plateau area of New Zealand enrolled in a study investigating the effect of vitamin B₁₂ injection on the growth of dairy calves at pasture.

Farm identity	Type	Start date	End date	Trial length (days)	Weighing events (n)	Pasture samples (n)
1	Dairy grazier	18/12/2017	24/07/2018	218	2	5
2	Run-off block	6/12/2017	3/05/2018	148	5	5
3	Run-off block	1/12/2017	4/05/2018	154	5	5
4	Dairy grazier	10/01/2018	7/06/2018	148	4	5
5	Dairy grazier	9/01/2018	28/06/2018	170	3	6
6	Run-off block	18/01/2018	3/07/2018	166	6	5
7	Run-off block	18/01/2018	3/07/2018	166	6	5

Table 3. Results of linear mixed effects regression models fitted to age, weight, and serum vitamin B₁₂ concentration at start of trial on seven farms from the Central Plateau area of New Zealand. The p-values show that there was no support for a difference in age, weight, and vitamin B₁₂ concentration, respectively, across the three treatment groups.

Variable	n	Mean	Range	P-value
Age at start of trial (days)	524	142.5	86–188	0.75
Weight at start of trial (kg)	559	118.6	77.5–189.0	0.79
Serum B12 concentration at start of trial (pmol/L)	104	166.4	11.2–533.7	0.53

Figure 1. Pasture cobalt concentration (mg/kg DM) by month for seven trial farms in the Central Plateau area of New Zealand enrolled in a trial investigating the effect of vitamin B₁₂ injection on the growth of dairy calves at pasture. The horizontal broken grey line indicates the recommended minimum pasture concentration (0.06 mg/kg DM) and the labels for the data points are the individual farm identifiers.