Considerable literature exists on the severe challenges faced by dairy cows at their transition from calving to lactation. Most studies focus on the transition period (TP) phase, which begins three weeks before calving and spans the first three weeks of lactation. Typically, this physiological phase implies severe alterations in the metabolic asset of dairy cows. These alterations are driven by sudden changes in hormonal trends and nutrient partitioning as well as by the adaptation of the animal’s metabolism to the negative energy and protein balance conditions driven by late pregnancy and early lactation requirements.
1. Introduction
Considerable literature exists on the severe challenges faced by dairy cows at their transition from calving to lactation. Most studies focus on the transition period (TP) phase, which begins three weeks before calving and spans the first three weeks of lactation
[1]. Typically, this physiological phase implies severe alterations in the metabolic asset of dairy cows. These alterations are driven by sudden changes in hormonal trends and nutrient partitioning
[2,3][2][3] as well as by the adaptation of the animal’s metabolism to the negative energy and protein balance conditions driven by late pregnancy and early lactation requirements
[4,5,6,7,8,9][4][5][6][7][8][9]. Dairy cows are also prone to developing immune dysfunctions in this phase. Such dysfunctions consist of two phenomena: (1) a reduced competence of the immune system, triggering a hypo-responsive state in polymorphonuclear cells (PMN) and lymphocytes starting about 2–3 weeks before calving, and reaching lowest efficiencies between the time of calving and two days after
[10[10][11][12],
11,12], and (2) the occurrence of systemic inflammation that triggers the acute phase response after parturition
[13]. Recently, Lopreiato et al
[14] reported that increasing the release of proinflammatory cytokines (PICs-interleukin-6 and interleukin-1β) upon PEG-rbG-CSF treatment in dairy cows after parturition did not result in increased systemic inflammation (as reflected by haptoglobin and ceruloplasmin plasma levels). This latter finding highlights that mechanisms and/or molecules other than PICs are likely to drive the acute phase response occurring in dairy cows after parturition. Thus, despite reduced competence of the immune system and systemic inflammation commonly appear together in dairy cows at their transition to calving
[15], these should be probably considered as two distinct phenomena. A recent review
[16] hypothesizes that a multifactorial etiology could be responsible for these dysfunctions and that their severity is directly related to the magnitude of metabolic changes faced by dairy cows. Together, these metabolic and immunologic challenges during the peripartal period are important factors that limit the ability of most cows to achieve optimal performance and balanced immune-metabolic status in early lactation.
The risk ratio of both metabolic and infectious diseases in early lactation is directly related to the magnitude of metabolic alteration and the degree of immune dysfunction faced by dairy cows during the periparturient period
[17,18,19][17][18][19]. In turn, the occurrence of disease (infectious and/or metabolic) in this physiological phase could further challenge the metabolism of dairy cows and impair the function of leukocytes, increasing the likelihood of other diseases
[20,21][20][21]. This vicious circle increases drug costs and could impair fertility of the animals, frequently resulting in their culling
[22,23][22][23].
2. How to Manage a “Good” Transition Period
2.1. Management Strategies and Facilities to Optimize Animal Welfare
Typically, transition cows flow successively into four pens: dry, prefresh, maternity, and fresh
[88][24]. Cows should enter the prefresh pen 21 days before expected parturition. Then, cows should be moved to the contiguous maternity pen, where they should stay alone for no longer than three days to avoid any distress from prolonged isolation. Finally, cows should be moved to the fresh pen, where they should stay for approximately 21–30 days postpartum, allowing closer monitoring and perhaps being fed a different diet from lactating cows (see
Table 1).
Table 1. Performances inputs, dietary recommendations, and sample diets for a medium-performance dairy cow undergoing the lactation, far-off, close-up and fresh phases (adapted from NRC
[67][25]).
Item 1 |
Unit |
Phase |
Lactation |
Far-Off |
Close-Up 4 |
Fresh |
Inputs |
|
|
|
|
|
Days 2 |
day |
90 |
240 |
270 |
11 |
Body weight 3 |
kg |
680 |
730 |
751 |
680 |
BCS |
- |
3 |
3.3 |
3.3 |
3.3 |
Age |
months |
49 |
57 |
58 |
58 |
Milk production |
kg |
35 |
- |
- |
35 |
Butterfat |
% |
3.5 |
- |
- |
3.5 |
True protein |
% |
3 |
- |
- |
3 |
Lactose |
% |
4.8 |
- |
- |
4.8 |
Dry matter intake |
kg |
23.6 |
14.4 |
13.7 |
15.6 |
Daily weight change |
kg |
0.3 |
0.67 |
0.67 |
−1.6 |
Days to gain one condition score |
day |
316 |
na |
na |
- |
Days to lose one condition score |
day |
- |
na |
na |
55 |
Dietary recommendations |
|
|
|
|
|
NEL |
Mcal/day |
34.8 |
14 |
14.4 |
34.8 |
NEL |
Mcal/kg DM |
1.47 |
0.97 |
1.54–1.62 |
2.23 |
MP |
g/day |
2407 |
871 |
910 |
2157 |
Diet MP |
% |
10.2 |
6 |
6.6 |
13.8 |
RDP |
g/day |
2298 |
1114 |
1358 |
1634 |
Diet RDP |
% |
9.7 |
7.7 |
9.9 |
10.5 |
RUP |
g/day |
1291 |
317 |
172 |
1405 |
Diet RUP |
% |
5.5 |
2.2 |
1.3 |
9 |
Diet NDF min |
% |
25–33 |
33 |
33 |
25–33 |
Diet ADF min |
% |
17–21 |
21 |
21 |
17–21 |
Diet NFC max |
% |
36–44 |
42 |
43 |
36–44 |
Absorbable Ca |
g/day |
65 |
18.1 |
21.5 |
64 |
Diet Ca |
% |
0.61 |
0.44 |
0.45 (0.5–1.5) |
0.79 |
Absorbable P |
g/day |
56.5 |
19.9 |
20.3 |
49 |
Diet P |
% |
0.35 |
0.22 |
0.3–0.4 |
0.42 |
Diet Mg |
% |
0.19 |
0.11 |
0.35–0.4 |
0.29 |
Diet Cl |
% |
0.26 |
0.13 |
0.15 (0.8–1.2) |
0.4 |
Diet K |
% |
1.04 |
0.51 |
0.52 |
1.24 |
Diet Na |
% |
0.23 |
0.1 |
0.1 |
0.34 |
Diet S |
% |
0.2 |
0.2 |
0.2 (0.3–0.4) |
0.2 |
Diet Co |
mg/kg DM |
0.11 |
0.11 |
0.11 |
0.11 |
Diet Cu |
mg/kg DM |
11 |
12 |
13 |
16 |
Diet I |
mg/kg DM |
0.5 |
0.4 |
0.4 |
0.77 |
Diet Fe |
mg/kg DM |
15 |
13 |
13 |
22 |
Diet Mn |
mg/kg DM |
14 |
16 |
18 |
21 |
Diet Se |
mg/kg DM |
0.3 |
0.3 |
0.3 |
0.3 |
Diet Zn |
mg/kg DM |
48 |
21 |
22 |
73 |
Diet vitamin A |
IU/kg DM |
3169 |
5576 |
6030 |
4795 |
Diet vitamin D |
IU/kg DM |
864 |
1520 |
1644 |
1308 |
Diet vitamin E |
IU/kg DM |
23 |
81 |
88 |
35 |
DCAD |
meq/kg DM |
na |
na |
10 (−75 to 0) |
na |
Sample diet (ingredients listed as kg/day DM) |
|
|
|
Corn silage, normal |
- |
8.21 |
- |
5.55 (5.40) |
36.44 |
Grass silage, mid-maturity |
- |
- |
8.1 |
2.48 (2.42) |
- |
Legume forage silage, mid-maturity |
- |
4.57 |
- |
- |
- |
Legume forage hay, immature |
- |
- |
- |
- |
20.17 |
Grass hay, mid-maturity |
- |
3.21 |
- |
- |
- |
Sugar beet pup, dried |
- |
- |
- |
2.15 (2.09) |
- |
Corn grain, steam flaked |
- |
4.33 |
- |
- |
18.29 |
Soybean meal, 48% CP |
- |
1.62 |
- |
0.79 (0.77) |
2.53 |
Soybean meal, expellers |
- |
- |
- |
- |
7.65 |
Blood meal, ring dried |
- |
- |
- |
- |
1.02 |
Cottonseed, whole with lint |
- |
- |
- |
- |
8.41 |
Calcium soaps of fatty acids |
- |
- |
- |
- |
0.65 |
Vitamin and mineral premix |
- |
0.49 |
0.02 |
0.43 (0.42) |
3.18 |
Calcium carbonate |
- |
0.07 |
0.46 |
- |
0.56 |
Calcium phosphate (di-) |
- |
- |
- |
0.05 (0.03) |
- |
Calcium chloride |
- |
- |
- |
- (0.14) |
- |
Monosodium phosphate |
- |
0.02 |
- |
- (0.07) |
0.4 |
Sodium chloride |
- |
0.011 |
5.79 |
0.03 |
0.7 |
Magnesium oxide |
- |
- |
- |
0.05 (0.03) |
- |