Influence of starter protein content on growth of dairy calves in an enhanced early nutrition program

Abstract

Our objectives were to determine the effect of starter crude protein (CP) content on growth of Holstein calves from birth to 10 wk of age in an enhanced early nutrition program, and to compare the enhanced program to a conventional milk replacer program. Calves (64 female, 25 male) were assigned to 3 treatments in a randomized block design: 1) conventional milk replacer (20% CP, 20% fat) plus conventional starter [19.6% CP, dry matter (DM) basis], 2) enhanced milk replacer (28.5% CP, 15% fat) plus conventional starter, and 3) enhanced milk replacer plus high-CP starter (25.5% CP, DM basis). Calves began treatments (n=29, 31, and 29 for treatments 1 to 3) at 3 d of age. Conventional milk replacer (12.5% solids) was fed at 1.25% of birth body weight (BW) as DM daily in 2 feedings from wk 1 to 5 and at 0.625% of birth BW once daily during wk 6. Enhanced milk replacer (15% solids) was fed at 1.5% of BW as DM during wk 1 and 2% of BW as DM during wk 2 to 5, divided into 2 daily feedings. During wk 6, enhanced milk replacer was fed at 1% of BW as DM once daily. Calves were weaned at d 42. Starter was available for ad libitum intake starting on d 3. Starter intake was greater for calves fed conventional milk replacer. For calves fed enhanced milk replacer, starter intake tended to be greater for calves fed enhanced starter. During the weaning period, enhanced starter promoted greater starter DM intake than the conventional starter. Over the 10-wk study, the average daily gain of BW (0.64, 0.74, and 0.80 kg/d) was greater for calves fed enhanced milk replacer with either starter and, for calves fed enhanced milk replacer, tended to be greater for calves fed high-CP starter. Rates of change in withers height, body length, and heart girth were greater for calves fed enhanced milk replacer but did not differ between starter CP concentrations. The postweaning BW for enhanced milk replacer treatments was greater for calves receiving the enhanced starter at wk 8 (73.7, 81.3, and 85.8 kg) and wk 10 (88.0, 94.9, and 99.9 kg). Starter CP content did not affect height, length, or heart girth within enhanced milk replacer treatments. Regression analysis showed that gain of BW during the first week postweaning (wk 7) increased with greater 3-d mean starter intake in the week before weaning. Starter with 25.5% CP (DM basis) provided modest benefits in starter intake (particularly around weaning) and growth for dairy calves in an enhanced early nutrition program compared with a conventional starter (19.6% CP).

Weaning age affects growth, feed intake, gastrointestinal development, and behavior in Holstein calves fed an elevated plane of nutrition during the preweaning stage

“…An alternative to weaning by age, which is common in our industry, is the traditional concentrate-or starter-dependent weaning strategy. Optimal preweaning starter intake before step down (>0.5 kg/d) is essential for postweaning intake and gain and is influenced by the nutrient content of the milk replacer and calf starter (Stamey et al, 2012;Kertz and Loften, 2013). Greenwood et al (1997) demonstrated that calves fed low planes of nutrition could be successfully weaned when starter intake reaches 1% of BW.…”

Desenvolvimento do trato digestivo de bezerros leiteiros criados em sistema de aleitamento fracionado

“…Entretanto, o consumo aumenta quando o volume de leite fornecido é reduzido ou cessado (Stamey et al 2005, Hill et al 2006, sendo essa relação inversa entre o leite e o consumo de ração sólida (Khan et al 2007, Terré et al 2007, Raeth--Knight et al 2009 Os pesos absolutos do trato digestivo, ruminorretículo, omaso e dos intestinos foram influenciados pelo sistema de aleitamento, sendo verificadas médias superiores nos bezerros do sistema de aleitamento fracionado (Quadro 3).…”

“…Adotar o aleitamento acelerado inicialmente, com restrições gradativas até a desmama, pode permitir que os bezerros se alimentem com quantidades de leite mais pró-ximas das condições em que os bezerros teriam acesso ad libitum ao leite (Stamey et al 2005). O aleitamento em volumes crescentes nas primeiras semanas de vida, seguido pela redução gradual até o desaleitamento vem sendo indicado, pois o fornecimento de grande quantidade de leite, durante todo o período, resulta em menor consumo de concentrado nas fases iniciais, tendo, como consequência, menor desenvolvimento do rúmen ao desaleitamento (Davis & Drackley 1998).…”

Management of Dairy Calves from Birth to Weaning

“…Using this approach, milk feeding rates are almost double the traditional feeding rates, giving calves 1.5% of body weight as milk solids during the fi rst week of life, followed by 2% of body weight from week 2 until the week before weaning, when one liquid feeding per day is dropped (Stamey et al, 2005 ;Drackley, 2008 ). Compared to conventional milk replacer feeding programs, accelerated milk replacer feeding programs can deliver expected growth rates of 1.3 -1.8 lb/day (0.59 -0.82 kg/day), compared to 1.1 -1.3 lb/day (0.50 -0.59 kg/ day) for conventionally fed calves from days 0 to 42 (Drackley, 2008 ).…”