Daytime management of the mare: 1: Pre-foaling mammary secretions testing

Fifty-six mares of lighthorse breeding were utilized in a controlled management scheme for induced daytime foaling. All mares had pre-foaling mammary secretions sampled for evaluation of water hardness (ppm) or calcium carbonate content (ppm). Sampling began 10 days prior to expected foaling date for each mare and was performed once daily for 3 days followed by twice daily until foaling occurred. Samples were diluted 1:6 in distilled water and tested by each of 3 methods: Sofchek™ Test Strips⁴, Predict-A-Foal™ Test Kit⁵ and Titrets™ Calcium Hardness Test Kit⁶. Mares were then either induced (i) to foal (no.= 33) according to a decision point of readiness for birth as indicated by pre-foaling mammary secretion testing (≥250 ppm water hardness by Sofchek™ test, ≥ 250 ppm calcium carbonate content by Titrets test, ≥ 4 color bar changes by Predict-A-Foal test), or allowed to foal spontaneously (s) (no.=23). There were no differences (p>0.05) in the mean pre-foaling mammary secretion test values (μ_i=293ppm, μ_s=329ppm; μ_i=4.1, μ_s=4.2; and μ_i=281ppm, μ_s=298ppm; for Sofchek, Predict-A-Foal and Titrets, respectively) between mare groups at the time of foaling (time=0) for any of the 3 testing methods employed. Mean intervals to foaling after reaching decision points of readiness for birth were different (p<0.05) between Sofchek and Titrets test for both mare groups, but only in the induced-to-foal group between Sofchek and Predict-A-Foal tests. Probabilities of 79%, 53% and 59% were calculated for mares foaling spontaneously within 24 hours of reaching the decision points used in this trial of readiness for birth on the initial occasion for Sofchek, Predict-A-Foal and Titrets™ tests, respectively. Each test was determined to have the ability to predict readiness of approaching parturition and found to be easily applicable to field use. The Titrets test was found to be least variable in its response to measurement of pre-foaling mammary secretion hardness changes both within and between mares.     

An evaluation of 4 commercially available ELISA kits for the diagnosis of Dirofilaria immitis infection in dogs

Serum samples from 100 pound dogs were used to evaluate 4 commercial ELISA kits available for the diagnosis of Dirofilaria immitis. The kits were assessed on sensitivity (the ability to identify infected dogs), specificity (the ability to identify uninfected dogs) and accuracy (sensitivity plus specificity). The kits varied in sensitivity from 36% to 86%, in specificity from 44% to 70%, and in accuracy from 53% to 65%. The sensitivity was not affected by the age of the dogs, nor by the number of circulating microfilariae. The kits were most specific when testing the youngest dogs (less than = 3 years). The problems associated with the serological diagnosis of D. immitis infection in practice are discussed.     

Are dual-purpose and male layer chickens more resilient against a low-protein-low-soybean diet than slow-growing broilers?

ABSTRACT

1. Although fattening dual-purpose types or male layer hybrid chickens appears more ethical than the common practice of culling day-old male layer chicks, the lower feed efficiency of these birds raises concerns. Replacing feed ingredients that compete with food production by those of lower value for human nutrition would be beneficial.

2. Lohmann Dual (LD), a modern dual-purpose type, Lohmann Brown (LB), a male layer hybrid, and Hubbard JA 957 (HU), a slow-growing broiler type, were fattened for nine weeks on two diets (control or ?20% crude protein; n = 6 × 12 birds). Growth, carcass and meat quality were analysed.

3. Growth performance of HU exceeded that of LD and especially of LB. The growth depression caused by the low-protein diet fed to LD (?7%) was only half of that found in HU (?13%). The LD fed the control diet had the same feed efficiency as the HU fed the low-protein diet. Even the LB had a lower performance and feed efficiency with the low-protein diet in growth. There was a gradient in carcass properties (weight, dressing percentage, breast meat yield, breast proportion and breast angle) from HU to LD to LB, with some additional adverse effects of the low-protein diet especially in HU. There were some breed differences in fatty acid profile in the intramuscular fat.

4. In conclusion, the dual-purpose type used complied with regulations for Swiss organic poultry systems in terms of growth rate and was found to respond less when fed a low-protein diet than the slow-growing broiler type. The LB males were inferior in all growth and carcass quality traits. Future studies need to determine the exact protein and amino acid requirements of dual-purpose and layer hybrid chickens and the economic feasibility of the systems, especially for organic farming.     

Effects of iron injection timing on suckling and subsequent nursery and growing-finishing performance and hematological criteria

Two experiments were conducted to evaluate the effects of Fe injection timing after birth on suckling and subsequent nursery and growing-finishing pig performance. The injectable Fe source used in both experiments was GleptoForte (Ceva Animal Health, LLC., Lenexa, KS). GleptoForte contains gleptoferron which is a Fe macromolecule complex. In Exp. 1, a total of 324 newborn pigs (DNA 241 × 600, initially 1.6 ± 0.04 kg body weight [BW]) within 27 litters were used. Two days after birth, all piglets were weighed, and six barrows and six gilts per litter were allotted to 1 of 6 treatments consisting of no Fe injection or 200 mg of injectable Fe provided in a single injection on d 2, 4, 6, 8, or 10 of age. Pigs were weaned (~21 d of age) and allotted to nursery pens with all pigs in each pen having received the same Fe treatment. In Exp. 2, a total of 1,892 newborn pigs (PIC 359 × C40; initially 1.5 ± 0.02 kg BW) within 172 litters were used. One day after birth, piglets were weighed, and 11 pigs within each litter were allotted to 1 of 6 treatments consisting of no Fe injection or 200 mg of injectable Fe provided on d 1, 3, 5, or 7 of age, or 200 mg on d 1 plus 200 mg on d 12 of age. Pigs were weaned (19 d of age) and placed in a commercial wean-to-finish facility in a total of 15 pens with equal representation of treatments in each pen. In both experiments, not providing an Fe injection after birth decreased (P < 0.05) preweaning average daily gain (ADG), weaning weight, and hemoglobin and hematocrit values compared with all other treatments. In Exp. 1, increasing the age that piglets received an Fe injection until 4 or 6 d after birth provided marginal evidence for an improvement (quadratic; P = 0.070) in preweaning ADG. For the nursery period, increasing the age that piglets received an Fe injection improved (quadratic; P = 0.013) d 80 BW, but there was no evidence of a difference (P > 0.10) in d 173 BW at the end of the grow-finish period. In Exp. 2, increasing the age that piglets received a 200 mg Fe injection showed no evidence of difference (P > 0.10) for subsequent nursery and growing-finishing ADG. In both experiments, hemoglobin and hematocrit values were decreased (linear; P < 0.05) at weaning with increasing age when pigs received an Fe injection. These experiments suggest that providing a 200 mg Fe injection within 7 d after farrowing is sufficient for optimizing preweaning and subsequent growth performance.