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Güz BC, Molenaar R, de Jong IC, Kemp B, van Krimpen M, van den Brand H. Effects of green light emitting diode light during incubation and dietary organic macro and trace minerals during rearing on tibia characteristics of broiler chickens at slaughter age. Poult Sci 2020; 100:707-720. [PMID: 33518124 PMCID: PMC7858192 DOI: 10.1016/j.psj.2020.11.042] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 10/15/2020] [Accepted: 11/23/2020] [Indexed: 01/22/2023] Open
Abstract
This study was designed to evaluate the effects of green light emitting diode (LED) light during incubation and dietary organic macro and trace minerals during rearing on tibia morphological, biophysical, and mechanical characteristics of broiler chickens at slaughter age. The experiment was setup as a 2 × 2 × 2 factorial arrangement, with the following treatments: 1) light during incubation (green LED light or darkness), 2) macro mineral source during rearing (organic or inorganic Ca and P), and 3) trace mineral source during rearing (organic or inorganic Fe, Cu, Mn, Zn, and Se). A total of 2,400 eggs (Ross 308) were either incubated under green LED light (16L:8D) or in complete darkness. After hatch, a total of 864 male broiler chickens were reared until slaughter age (day 42) and provided with 1 of 4 diets, differing in macro and/or trace mineral source. During rearing, the experiment had a complete randomized block design with 9 replicate pens per treatment and 12 chickens per pen. At slaughter age (day 42), 2 chickens per replicate were randomly selected and tibia bones were obtained. Tibia weight, length, thickness, osseous volume, pore volume, total volume, mineral content, mineral density, ultimate strength, and stiffness were determined. Green LED light during incubation did not affect any of the tibia characteristics. Dietary organic macro minerals positively affected most of the tibia morphological, biophysical, and mechanical characteristics compared to the inorganic macro minerals, whereas trace mineral sources did not affect tibia characteristics. It can be concluded that dietary organic macro minerals Ca and P stimulated tibia characteristics, whereas green LED light during incubation and dietary trace minerals during rearing did not affect tibia characteristics, locomotion, or leg disorders.
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Hollemans MS, van Baal J, de Vries Reilingh G, Kemp B, Lammers A, de Vries S. Intestinal epithelium integrity after delayed onset of nutrition in broiler chickens. Poult Sci 2020; 99:6818-6827. [PMID: 33248597 PMCID: PMC7704972 DOI: 10.1016/j.psj.2020.08.079] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 08/18/2020] [Accepted: 08/24/2020] [Indexed: 12/20/2022] Open
Abstract
Fasting older broiler chickens (>7 d of age) enlarges the intestinal tight junction (TJ) pore size, resulting in high paracellular intestinal permeability. Broiler chickens often do not receive feed and water (nutrition) directly after hatch, which may result in fasting up to 72 h of age. Whether perinatal fasting affects intestinal permeability is minimally studied. We therefore investigated whether delayed access to nutrition after hatch increases intestinal permeability, compared with broilers receiving early access to nutrition. Therefore, 432 hatched broilers received nutrition 72 h after hatch (delayed nutrition [DN]) or directly after hatch (early nutrition [EN]) and were reared under similar conditions until 14 d of age. Two hours after application of an oral pulse dose (3.85 mg) of fluorescein isothiocyanate-dextran (4000 Da) at 4, 10, and 14 d of age, blood plasma concentrations of the marker were measured in 24 to 36 broilers per treatment and time point. Marker concentration in plasma did not differ between DN and EN broilers at any age. The villus width measured in at least 8 broilers per treatment was smaller in DN than in EN broilers at 4 d for both the ileum (92 ± 3 μm vs. 121 ± 4; P < 0.001) and colon (100 ± 3 vs. 120 ± 4; P < 0.01). Real-time quantitative PCR revealed that the expression of TJ protein claudin 3 in the ceca was elevated in DN, compared with EN broilers at 4 d of age, whereas that of zonula occludens 1 in the ileum was reduced. Expression of host defense-related genes was reduced in DN, compared with EN broilers, in the ileum (cyclo-oxygenase 2, mucin 2) and ceca (interleukin 1β, cyclo-oxygenase 2). We conclude that 72-hour DN reduced the BW up to 14 d of age, coinciding with transient effects on the villus width in the ileum and colon, and divergent expression of genes involved in TJ formation and host defense. These effects likely reflect the delayed onset of intestinal and immune development in DN, compared with EN broilers, while DN does not fundamentally alter intestinal permeability.
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Napolitano R, Molloholli M, Donadono V, Ohuma EO, Wanyonyi SZ, Kemp B, Yaqub MK, Ash S, Barros FC, Carvalho M, Jaffer YA, Noble JA, Oberto M, Purwar M, Pang R, Cheikh Ismail L, Lambert A, Gravett MG, Salomon LJ, Bhutta ZA, Kennedy SH, Villar J, Papageorghiou AT. International standards for fetal brain structures based on serial ultrasound measurements from Fetal Growth Longitudinal Study of INTERGROWTH-21 st Project. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2020; 56:359-370. [PMID: 32048426 DOI: 10.1002/uog.21990] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 01/27/2020] [Accepted: 01/27/2020] [Indexed: 06/10/2023]
Abstract
OBJECTIVE To create prescriptive growth standards for five fetal brain structures, measured using ultrasound, in healthy, well-nourished women at low risk of impaired fetal growth and poor perinatal outcome, taking part in the Fetal Growth Longitudinal Study (FGLS) of the INTERGROWTH-21st Project. METHODS This was a complementary analysis of a large, population-based, multicenter, longitudinal study. The sample analyzed was selected randomly from the overall FGLS population, ensuring an equal distribution among the eight diverse participating sites and of three-dimensional (3D) ultrasound volumes across pregnancy (range: 15-36 weeks' gestation). We measured, in planes reconstructed from 3D ultrasound volumes of the fetal head at different timepoints in pregnancy, the size of the parieto-occipital fissure (POF), Sylvian fissure (SF), anterior horn of the lateral ventricle, atrium of the posterior horn of the lateral ventricle (PV) and cisterna magna (CM). Fractional polynomials were used to construct the standards. Growth and development of the infants were assessed at 1 and 2 years of age to confirm their adequacy for constructing international standards. RESULTS From the entire FGLS cohort of 4321 women, 451 (10.4%) were selected at random. After exclusions, 3D ultrasound volumes from 442 fetuses born without a congenital malformation were used to create the charts. The fetal brain structures of interest were identified in 90% of cases. All structures, except the PV, showed increasing size with gestational age, and the size of the POF, SF, PV and CM showed increasing variability. The 3rd , 5th , 50th , 95th and 97th smoothed centiles are presented. The 5th centiles for the POF and SF were 3.1 mm and 4.7 mm at 22 weeks' gestation and 4.6 mm and 9.9 mm at 32 weeks, respectively. The 95th centiles for the PV and CM were 8.5 mm and 7.5 mm at 22 weeks and 8.6 mm and 9.5 mm at 32 weeks, respectively. CONCLUSIONS We have produced prescriptive size standards for fetal brain structures based on prospectively enrolled pregnancies at low risk of abnormal outcome. We recommend these as international standards for the assessment of measurements obtained using ultrasound from fetal brain structures. © 2020 Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
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Ha T, Kemp B, Wallace M. Hybrid team based learning-personalised education for teaching epidemiology in public health degrees. Eur J Public Health 2020. [DOI: 10.1093/eurpub/ckaa165.312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
University education in Australia and internationally involves teaching diverse students: in terms of age, life experience, previous degrees completed, and level of English competency. In Australia the Bachelors of Public Health (BPH) at The University of Wollongong, epidemiology is a core subject. It aims to equip students with the knowledge and skills needed to design, critique and interpret studies that investigate why different populations experience different health outcomes. A student-centred learning strategy; Hybrid Team Based Learning and Personalised Education teaching strategy (HTBL-PE) was created to maximise academic success. Each phase has a distinct purpose based on learning theories (e.g. TBL, Bloom's taxonomy and Vygotsky). HTBL-PE aims to systematically build students abilities; strengthen self-confidence and belief, by teaching the way students learn and harnessing the capabilities of the team to strengthen the individual.
Objectives
HTBL-PE was evaluated in spring 2019 in the BPH, where their experiences at the beginning and end of semester were measured.
Results
In total 73 out of 84 enrolled students provided data at both time-points (87%). At the end of the semester, the vast majority of students indicated their interest in epidemiology had increased (93%), critical thinking had improved (92%), and confidence as independent learners had increased (86%). Outcomes did not differ significantly by gender or across learning styles. More than two thirds of students had already applied learnings from this subject in other settings (67%). Students' final mark for this subject was significantly higher than their Weighted Average Mark (WAM) prior to the semester (+17.4, p < 0.001). Average scores for the subject were > 84/100 with a < 0.5% failure rate.
Conclusions
HTBL-PE has positive learning outcomes; low failure rates, increased confidence in learning and themselves, increased interest in epidemiology and high overall scores in the subject.
Key messages
An effective new innovative teaching strategy resulted in a subject average score > 84/100 and <0.5% failure rate. The vast majority of students reported increased confidence as independent lifelong learners, critical thinking, confidence in epidemiology (knowledge, skills, and attitudes) and themselves.
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Wijnen HJ, Molenaar R, van Roovert-Reijrink IAM, van der Pol CW, Kemp B, van den Brand H. Effects of incubation temperature pattern on broiler performance. Poult Sci 2020; 99:3897-3907. [PMID: 32731976 PMCID: PMC7597978 DOI: 10.1016/j.psj.2020.05.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 05/15/2020] [Accepted: 05/22/2020] [Indexed: 11/25/2022] Open
Abstract
During incubation, development of embryos is affected by eggshell temperature (EST). A constant EST of 37.8°C has been considered so far to result in most optimal embryo development. However, it can be hypothesized that a higher EST in week 2 in combination with a lower EST in week 3 stimulates embryo development and subsequent grow-out performance. In this study, 468 eggs of a 44-week-old Ross 308 breeder flock were incubated at different incubation temperature patterns in a 2 × 2 factorial arrangement. In week 2, EST was either 37.8°C or 38.9°C, and in week 3, EST was either 37.8°C or 36.7°C. At hatch, chick quality was determined. Thereafter, 320 broilers were grown in 32 pens (8 replicates/treatment) for 6 wk. Weekly BW and ADFI were determined, and at day 40, slaughter yield from 128 broilers (4 per pen) was determined. Results showed that EST in week 2 did not interact with EST in week 3 for any variable. An EST of 38.9°C in week 2 resulted in a 1 mm longer chick length (P < 0.001) and 0.4 mmol/L lower blood glucose level (P = 0.04) at hatch than an EST of 37.8°C. Grow-out performance was not affected by EST in week 2 of incubation. An EST of 36.7°C in week 3 resulted in a 1 mm shorter chick length (P = 0.02), 1.0 mmol/L higher blood glucose level (P < 0.001), and higher relative heart (P = 0.01) and stomach weights (P = 0.03) at hatch than an EST of 37.8°C. Additionally, an EST of 36.7°C in week 3 resulted in lower BW, ADG, and ADFI on slaughter age (all P < 0.03) than an EST of 37.8°C. In conclusion, no interaction between EST in week 2 and 3 of incubation was found for any variable. A higher EST in week 2 had minor effects at hatching and during rearing, whereas a lower EST in week 3 seemed to result in better organ development, but resulted in lower grow-out performance.
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Burgers EEA, Kok A, Goselink RMA, Hogeveen H, Kemp B, van Knegsel ATM. Fertility and milk production on commercial dairy farms with customized lactation lengths. J Dairy Sci 2020; 104:443-458. [PMID: 32747099 DOI: 10.3168/jds.2019-17947] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 05/25/2020] [Indexed: 11/19/2022]
Abstract
Drying-off, calving, and start of lactation are critical transition events for a dairy cow. As a consequence, most animal health issues occur during these periods. By extending the voluntary waiting period for first insemination after calving, calving interval (CInt) can be extended, with possible positive effects for fertility and health. Some cows might be better suited for an extended CInt than others, due to differences in milk yield level, lactation persistency, or health status, which would justify a customized CInt based on individual cow characteristics. This study aims to investigate 13 farms with customized CInt, with respect to calving to first service interval (CFSI), accomplished CInt, services per conception (SC), conception rate at first artificial insemination (CR1AI), peak yield, lactation persistency, 305-d yield, and effective lactation yield. In total, 4,858 complete lactations of Holstein Friesian cows between 2014 and 2019 from the 13 farms were grouped by parity (1 or 2+) and CFSI (CFSI class; CFSI-1 < 84; 84 ≤ CFSI-2 < 140; 140 ≤ CFSI-3 < 196; 196 ≤ CFSI-4 < 252, CFSI-5 ≥ 252 d) or CInt (CInt class; CInt-1 < 364; 364 ≤ CInt-2 < 420; 420 ≤ CInt-3 < 476; 476 ≤ CInt-4 < 532, CInt-5 ≥ 532 d). Cow inseminations, available for 11 out of 13 farms (3,597 complete lactations), were grouped by parity (1 and 2+) and CFSI class or CInt class. The fertility and milk production characteristics were analyzed with generalized and general linear mixed models. The CFSI class was not associated with SC, but extended CInt class was associated with increased SC (CInt-1-5; 1.11-3.70 SC). More than 50% of cows in the CFSI class <84 d ended up in longer than expected CInt (>364 d), showing that these cows were not able to conceive for the desired CInt. More than 50% of cows in CInt classes 3 and higher (CInt ≥ 420 d) had an earlier first insemination before successful insemination (CFSI class 1; <196 d), showing that these extended CInt classes consisted of both cows with an extended waiting period for first insemination and cows that failed to conceive at earlier insemination(s). On most farms, lactation persistency was greatest in CInt class 1 (<364 d), probably related to the low peak yield in this class. When this shortest CInt class was excluded, persistency increased with extended CInt classes on most farms. Although at the majority of farms 305-d yield was greater in CInt ≥ 532 d, effective lactation yield at most farms was greatest in CInt from 364 to 531 d, especially for multiparous cows. Based on the results of this study, a CInt between 364 and 531 days seems most optimal for milk production, when high-yielding cows were selected.
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Güz BC, Molenaar R, de Jong IC, Kemp B, van den Brand H, van Krimpen M. Effects of dietary organic minerals, fish oil, and hydrolyzed collagen on growth performance and tibia characteristics of broiler chickens. Poult Sci 2020; 98:6552-6563. [PMID: 31392338 PMCID: PMC6870562 DOI: 10.3382/ps/pez427] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 07/16/2019] [Indexed: 12/24/2022] Open
Abstract
Nutrition is a crucial factor for growth and bone development in broiler chickens. Adjustments in dietary ingredients might affect bone development and consequently locomotion related problems. This study was designed to evaluate effects of dietary organic minerals (ORM), fish oil (FISH), and hydrolyzed collagen (COL) on growth performance and tibia characteristics of broiler chickens. A total of three hundred eighty four 1-day-old Ross 308 male broiler chickens were used in a complete randomized block design with 4 diet groups and 8 replicates per diet group. In the ORM diet, the inorganic macro and trace minerals were replaced by their organic varieties. In the FISH diet, palm oil and soybean oil were partly replaced by FISH. In the COL diet, soybean meal was partly replaced by COL. Results showed that the ORM and COL diet groups reached a higher body weight (BW) at 42 D of age than the FISH diet group, whereas the control group was in between. The feed conversion ratio between day 1 and 42 was lower in the ORM and COL diet groups than in both other diet groups. On day 28, 35, and 42, gait score (GS), Varus Valgus deformity, tibia length (TL), thickness, femoral and metatarsal head thickness (THT), mineral content (TMC), mineral density (TMD), breaking strength (TBS), stiffness (TSF), and energy to fracture (TEF) were measured (n = 3/replicate). The ORM diet group had higher TL at day 42, higher THT at day 28, higher TMC at day 42, higher TMD at day 28, 35, and 42, higher TBS at day 42, higher TSF at day 35 and 42, and higher TEF at day 42 compared to the FISH diet group, with the COL and control diet groups in between. It can be concluded that replacing dietary inorganic macro and trace minerals by their organic varieties seems to stimulate tibia dimensions, strength, and mineral content of broiler chickens. On the contrary, FISH appears to negatively affect tibia characteristics.
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Güz B, Molenaar R, de Jong I, Kemp B, van den Brand H, van Krimpen M. Effects of dietary organic minerals, fish oil, and hydrolyzed collagen on growth performance and tibia characteristics of broiler chickens. Poult Sci 2020. [DOI: 10.1016/j.psj.2020.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Güz BC, Molenaar R, de Jong IC, Kemp B, van Krimpen M, van den Brand H. Effects of eggshell temperature pattern during incubation on tibia characteristics of broiler chickens at slaughter age. Poult Sci 2020; 99:3020-3029. [PMID: 32475438 PMCID: PMC7597550 DOI: 10.1016/j.psj.2019.12.042] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 12/11/2019] [Accepted: 12/18/2019] [Indexed: 11/15/2022] Open
Abstract
This study was designed to determine effects of eggshell temperature (EST) pattern in week 2 and week 3 of incubation on tibia development of broiler chickens at slaughter age. A total of 468 Ross 308 eggs were incubated at an EST of 37.8°C from incubation day (E) 0 to E7. Thereafter, a 2 × 2 factorial arrangement with 2 EST (37.8°C and 38.9°C) from E8 to E14 and 2 EST (36.7°C and 37.8°C) from E15 till hatch was applied. After hatching, chickens were reared until slaughter age with the 4 EST treatments and 8 replicates per treatment. At day 41 and 42, one male chicken per replicate per day was selected, and hock burn and food pad dermatitis were scored. Rotated tibia, tibia dyschondroplasia, epiphyseal plate abnormalities, bacterial chondronecrosis with osteomyelitis, and epiphysiolysis were assessed. Tibia weight, length, thickness, head thickness, and robusticity index were determined. X-ray analyses (osseous volume, pore volume, total volume, volume fraction, mineral content, and mineral density) and a 3-point bending test (ultimate strength, yield strength, stiffness, energy to fracture, and elastic modulus) were performed. A high EST (38.9°C) in week 2 of incubation, followed by a normal EST (37.8°C) in week 3 resulted in higher mineral content (P = 0.001), mineral density (P = 0.002), ultimate strength (P = 0.04), yield strength (P = 0.03), and stiffness (P = 0.05) compared with the other 3 EST groups (week 2 × week 3 interaction). A high EST (38.9°C) in week 2 of incubation, regardless of the EST in week 3, resulted in a higher tibia weight (P < 0.001), thickness (P = 0.05), osseous volume (P < 0.001), and total volume (P < 0.001) than a normal EST (37.8°C). It can be concluded that 1.1°C higher EST than normal in week 2 of incubation appears to stimulate tibia morphological, biophysical, and mechanical characteristics of broiler chickens at slaughter age. Additionally, a 1.1°C lower EST in week 3 of incubation appears to have negative effects on tibia characteristics, particularly in interaction with the EST in week 2 of incubation.
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Marcato F, van den Brand H, Kemp B, Engel B, Wolthuis-Fillerup M, van Reenen K. Effects of pretransport diet, transport duration, and type of vehicle on physiological status of young veal calves. J Dairy Sci 2020; 103:3505-3520. [PMID: 32037174 DOI: 10.3168/jds.2019-17445] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Accepted: 12/09/2019] [Indexed: 01/04/2023]
Abstract
This study aimed to investigate effects of pretransport diet (rearing milk vs. electrolytes), type of vehicle (open vs. conditioned truck), and transport duration (6 vs. 18 h) on physiological status of young calves upon arrival at the veal farm. A total of 368 calves were transported in 2 consecutive batches from a collection center to a veal farm. Blood samples were collected from calves before transport; immediately posttransport (T0); and 4, 24, and 48 h, and 1, 3, and 5 wk posttransport. Blood was analyzed for glucose, urea, lactate, nonesterified fatty acids (NEFA), β-hydroxybutyrate (BHB), creatine kinase, albumin, total protein, osmolality, calcium, sodium, magnesium, and hematological variables. Body weight, rectal temperature, and skin elasticity were determined before and immediately posttransport. Blood glucose, NEFA, and urea concentrations at T0 showed an interaction between pretransport diet and transport duration. Milk-fed and electrolyte-fed calves transported for 18 h did not significantly differ in plasma glucose concentration or serum NEFA concentrations. However, after 6 h of transport, milk-fed calves had higher plasma glucose and lower serum NEFA concentrations (4.71 mmol/L and 586.5 µmol/L, respectively) than electrolyte-fed calves (3.56 mmol/L and 916 µmol/L, respectively). After 18 h of transport, milk-fed calves had lower urea concentrations (5.40 mmol/L) than electrolyte-fed calves (7.38 mmol/L). In addition, at T0, after 6 h of transport, milk-fed calves gained weight (Δ = 0.41 kg), whereas electrolyte-fed calves lost weight (Δ = -0.16 kg). After 18 h of transport, both milk-fed and electrolyte-fed calves showed body weight losses (Δ = -0.67 and -0.74 kg, respectively). Type of vehicle had a limited influence on blood parameters. Concentrations of NEFA and BHB reached the maximum values at T0 and then decreased until wk 5 posttransport. The increase in NEFA and BHB concentrations between prior to and just posttransport (T0) was less pronounced in calves transported for 6 h (746.1 µmol/L and 0.38 mmol/L, respectively) than in calves transported for 18 h (850.6 µmol/L and 0.50 mmol/L). Overall, the recovery rate of calves at the veal farm seemed rapid; all blood parameters returned to (below) pretransport values within 48 h posttransport. We concluded that feeding milk before short-term transport helps young veal calves cope with transport, whereas this is not the case during long-term transport.
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Luo L, Reimert I, Graat EAM, Smeets S, Kemp B, Bolhuis JE. Effects of early life and current housing on sensitivity to reward loss in a successive negative contrast test in pigs. Anim Cogn 2019; 23:121-130. [PMID: 31720926 PMCID: PMC6981316 DOI: 10.1007/s10071-019-01322-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 10/01/2019] [Accepted: 10/22/2019] [Indexed: 10/25/2022]
Abstract
Animals in a negative affective state seem to be more sensitive to reward loss, i.e. an unexpected decrease in reward size. The aim of this study was to investigate whether early-life and current enriched vs. barren housing conditions affect the sensitivity to reward loss in pigs using a successive negative contrast test. Pigs (n = 64 from 32 pens) were housed in barren or enriched conditions from birth onwards, and at 7 weeks of age experienced either a switch in housing conditions (from barren to enriched or vice versa) or not. Allotting pigs to the different treatments was balanced for coping style (proactive vs. reactive). One pig per pen was trained to run for a large reward and one for a small reward. Reward loss was introduced for pigs receiving the large reward after 11 days (reward downshift), i.e. from then onwards, they received the small reward. Pigs housed in barren conditions throughout life generally had a lower probability and higher latency to get the reward than other pigs. Proactive pigs ran overall slower than reactive pigs. After the reward downshift, all pigs ran slower. Nevertheless, reward downshift increased the latency and reduced the probability to get to the reward, but only in pigs exposed to barren conditions in early life, which thus were more sensitive to reward loss than pigs from enriched early life housing. In conclusion, barren housed pigs seemed overall less motivated for the reward, and early life housing conditions had long-term effects on the sensitivity to reward loss.
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Costermans NGJ, Keijer J, van Schothorst EM, Kemp B, Keshtkar S, Bunschoten A, Soede NM, Teerds KJ. In ovaries with high or low variation in follicle size, granulosa cells of antral follicles exhibit distinct size-related processes. Mol Hum Reprod 2019; 25:614-624. [DOI: 10.1093/molehr/gaz042] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 06/28/2019] [Indexed: 01/16/2023] Open
Abstract
Abstract
Antral follicle size might be a valuable additive predictive marker for IVF outcome. To better understand consequences of antral follicle size as a marker for reproductive outcome, we aimed to obtain insight in follicle size-related granulosa cell processes, as granulosa cells play an essential role in follicular development via the production of growth factors, steroids and metabolic intermediates. Using the pig as a model, we compared gene expression in granulosa cells of smaller and larger follicles in the healthy antral follicle pool of sows, which had a high variation versus low variation in follicle size. Selected gene expression was confirmed at the protein level. Granulosa cells of smaller antral follicles showed increased cell proliferation, which was accompanied by a metabolic shift towards aerobic glycolysis (i.e. the Warburg effect), similar to other highly proliferating cells. High granulosa cell proliferation rates in smaller follicles might be regulated via increased granulosa cell expression of the androgen receptor and the epidermal growth factor receptor, which are activated in response to locally produced mitogens. While granulosa cells of smaller follicles in the pool are more proliferative, granulosa cells of larger follicles express more maturation markers such as insulin-like growth factor-1 (IGF1) and angiopoietin 1 (ANGPT1) and are therefore more differentiated. As both higher IGF1 and ANGPT1 have been associated with better IVF outcomes, the results of our study imply that including smaller follicles for oocyte aspiration might have negative consequences for IVF outcome.
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van den Brand H, van de Kraats SJF, Sözcü A, Jöerissen R, Heetkamp MJW, van den Anker I, Ooms M, Kemp B. Both the rooster line and incubation temperature affect embryonic metabolism and hatchling quality in laying hen crossbreds. Poult Sci 2019; 98:2632-2640. [PMID: 30690584 PMCID: PMC6527512 DOI: 10.3382/ps/pez007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 01/07/2019] [Indexed: 11/20/2022] Open
Abstract
Effects of 3 eggshell temperatures (EST; 36.7. 37.8, and 38.9°C) in 2 genetic laying hen crossbreds (AB and BB; same hen line, different rooster line) on embryonic metabolism and hatchling quality were investigated. EST were applied from day 14.5 of incubation (E14.5) until hatching. The experiment consisted of 6 consecutive batches with eggs weighing between 59 and 61 g. Heat production was determined continuously from E14.5 onward. In fresh eggs, yolk weight tended to be higher (Δ = 0.28 g; P = 0.08) in the AB crossbred than in the BB crossbred. At E14.5 and E18.5, yolk-free body mass (YFBM) and residual yolk (RY) weight did not differ between genetic crossbred and EST. Hatching time after the start of incubation was not affected by genetic crossbred, but was longer in the 36.7°C (517 h) than in the 38.9°C (505 h), with 37.8°C in between (506 h). At 6 h after hatching, no differences between crossbreds were found for chicken quality parameters, such as chicken weight, chicken length, RY, YFBM, and organ weights, but heart weight was higher in the 36.7°C EST than in the other 2 EST (Δ = 0.24 to 0.30% of YFBM, P = 0.005). Intestinal weight was higher at 36.7°C EST than at 38.9°C EST (Δ = 0.79% of YFBM; P = 0.02), with 37.8°C EST in between. Heat production between E14.5 and E18.5 was higher in the AB crossbred than in the BB crossbred (Δ = 2.61%, P < 0.001) and regardless of crossbred higher at an EST of 38.9°C than at other 2 EST (Δ = 3.59% on average; P < 0.001). Hatchling quality determined at pulling (E21.5) was not affected by EST, but AB chickens were lighter (Δ = 0.46 g; P = 0.03), had less red hocks (Δ = 0.03; P = 0.02), more red beaks (Δ = 0.10; P < 0.001), and a higher (worse) navel score (Δ = 0.11; P < 0.001) than BB chickens. It can be concluded that not only incubation temperature, but also the rooster line appears to play a role in layer crossbred embryo metabolism and hatchling quality.
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van den Bosch M, Wijnen J, van de Linde I, van Wesel A, Melchior D, Kemp B, van den Brand H, Clouard C. Effects of maternal dietary nitrate supplementation on farrowing and placental characteristics, level of asphyxiation at birth and piglet vitality. Theriogenology 2019; 129:1-7. [DOI: 10.1016/j.theriogenology.2019.01.033] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 12/06/2018] [Accepted: 01/31/2019] [Indexed: 11/29/2022]
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Lamot DM, Sapkota D, Wijtten PJA, van den Anker I, Heetkamp MJW, Kemp B, van den Brand H. Diet density during the first week of life: Effects on growth performance, digestive organ weight, and nutrient digestion of broiler chickens. Poult Sci 2019; 98:789-795. [PMID: 30544262 DOI: 10.3382/ps/pey002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Accepted: 11/30/2018] [Indexed: 11/20/2022] Open
Abstract
The current study aimed to investigate whether diet density affects growth performance and nutrient digestion during the first wk after hatch and digestive organ weight at 7 d of age. Effects were studied using a dose-response design consisting of 5 dietary fat levels (3.5, 7.0, 10.5, 14.0, and 17.5%). The dietary fat level was increased through soybean oil inclusion. Amino acids, minerals, and the premix were increased at the same ratio as dietary fat. Consequently, diets were kept neither isocaloric nor isonitrogenous. Broiler chickens were weighed on d 0 and d 7 after hatch, whereas feed intake was measured daily. Excreta produced from d 0 to d 7 was collected at d 7. Dietary dry matter and nitrogen metabolizability, as well as fat digestibility were calculated as an average over 7 days. Broiler chickens were sampled at d 7 to determine carcass yield, breast meat yield, and organ weights. Average daily gain (P = 0.047) and average daily feed intake (P < 0.001) decreased linearly as diet density increased, while gain to feed ratio increased linearly (P < 0.001). An increased diet density resulted in a linear decrease of crop, liver, and pancreas weight relative to body weight (BW; P < 0.05). Duodenum, jejunum, ileum, and cecum length (expressed as cm/kg of BW) and empty weight (as % of BW) increased linearly with increased diet density (P < 0.05). Dietary dry matter metabolizability decreased linearly as diet density increased (P < 0.001), whereas fat digestibility and nitrogen metabolizability were not affected (P > 0.05). In conclusion, one-week-old broiler chickens respond to increased diet densities by increasing intestinal weight and length, while decreasing liver and pancreas weight. This may be an adaptive response to cope with an increased nutrient concentration in the diet.
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Hayama S, Duller G, Sutter JP, Amboage M, Boada R, Freeman A, Keenan L, Nutter B, Cahill L, Leicester P, Kemp B, Rubies N, Diaz-Moreno S. The scanning four-bounce monochromator for beamline I20 at the Diamond Light Source. JOURNAL OF SYNCHROTRON RADIATION 2018; 25:1556-1564. [PMID: 30179197 PMCID: PMC6140387 DOI: 10.1107/s1600577518008974] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 06/19/2018] [Indexed: 05/29/2023]
Abstract
A description of the technical and design details of a scanning four-bounce crystal monochromator that has recently been commissioned for the Versatile X-ray Absorption Spectroscopy (XAS) beamline at Diamond Light Source is presented. This device consists of two independent rotary axes of unique design which are synchronized using a multiple read-head encoder system. This monochromator is shown to be capable of maintaining the flux throughput of the Bragg axes without the need of any external feedback mechanism from 4 to 20 keV. The monochromator is currently equipped with cryogenically cooled crystals with the upstream axis consisting of two independent Si(111) crystals and a pair of channel-cut crystals in the downstream axis. The possibility of installing an additional Si(311) crystal-set to extend the energy range to 34 keV is incorporated into the preliminary design of the device. Experimental data are presented showing the exceptional mechanical stability and repeatability of the monochromator axes.
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van Asselt M, Poortvliet PM, Ekkel ED, Kemp B, Stassen EN. Risk perceptions of public health and food safety hazards in poultry husbandry by citizens, poultry farmers and poultry veterinarians. Poult Sci 2018; 97:607-619. [PMID: 29161444 PMCID: PMC5850310 DOI: 10.3382/ps/pex325] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 10/06/2017] [Indexed: 01/04/2023] Open
Abstract
Differences in risk perceptions of public health and food safety hazards in various poultry husbandry systems by various stakeholder groups, may affect the acceptability of those husbandry systems. Therefore, the objective was to gain insight into risk perceptions of citizens, poultry farmers, and poultry veterinarians regarding food safety and public health hazards in poultry husbandry systems, and into factors explaining these risk perceptions. We surveyed risk perceptions of Campylobacter contamination of broiler meat, avian influenza introduction in laying hens, and altered dioxin levels in eggs for the most commonly used broiler and laying hen husbandry systems in Dutch citizens (n = 2,259), poultry farmers (n = 100), and poultry veterinarians (n = 41). Citizens perceived the risks of the three hazards in the indoor systems higher and in the outdoor systems lower than did the professionals. Citizens reported higher concerns regarding aspects reflecting underlying psychological factors of risk perception compared to professionals. Professionals indicated a relatively low level of personal control, which might imply risk denial. Of the socio-demographic characteristics, gender and childhood residence were associated with risk perceptions. The influence of other factors of risks perception are discussed. It is suggested that risk perceptions of all stakeholder groups are influenced by affect, stigma, and underlying values. To adapt current or new husbandry systems that can count on societal support, views of key stakeholders and multiple aspects such as animal welfare, public health, food safety, and underlying values should be considered integrally. When trade-offs, such as between animal welfare and public health have to be made, insight into underlying values might help to find consensus among stakeholders.
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van Hoeij R, Lam T, Bruckmaier R, Dijkstra J, Remmelink G, Kemp B, van Knegsel A. Udder health of dairy cows fed different dietary energy levels after a short or no dry period without use of dry cow antibiotics. J Dairy Sci 2018; 101:4570-4585. [DOI: 10.3168/jds.2017-13448] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Accepted: 12/15/2017] [Indexed: 01/20/2023]
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Hoving LL, Haen SM, Laurenssen BFA, Peltoniemi OAT, Kemp B, Soede NM. Caudal vena cava progesterone and LH release patterns on Day 14 of gestation in primiparous sows. Reprod Fertil Dev 2018; 29:476-481. [PMID: 28442059 DOI: 10.1071/rd15016] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Accepted: 08/05/2015] [Indexed: 11/23/2022] Open
Abstract
The aim of the present study was to explore the relationship between systemic and local progesterone secretion and LH pulsatility during implantation in the pig. Differences in progesterone concentrations measured locally in the caudal vena cava and systemically in the jugular vein were studied in eight primiparous sows on Day 14 of pregnancy. LH pulsatility was analysed for its effects on the local progesterone-releasing pattern. Mean (±s.d.) progesterone concentrations in the vena cava (65.5±19.8ngmL-1) were approximately double basal concentrations (33.6±13.1ngmL-1). Basal concentrations of progesterone and LH were calculated as the average of the lowest six values. Basal caudal vena cava and mean jugular (27.6±1.5ngmL-1) progesterone concentrations did not differ significantly. Pre- and postprandial jugular progesterone concentrations were significantly different in the morning and afternoon (P=0.025 and 0.023). Mean LH ranged from 0.24 to 0.43ngmL-1 and was approximately double as high as basal LH in individual sows. In 60.8% of cases, LH pulses were followed by a progesterone pulse within 1h. In conclusion, the present study showed that corpus luteum function appears to respond to LH pulsatility on Day 14 of pregnancy. However, the response varies at the level of individual sows. In addition, systemic postprandial decreases in progesterone were confirmed on Day 14 of pregnancy.
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Da Silva CLA, Broekhuijse MLWJ, Laurenssen BFA, Mulder HA, Knol EF, Kemp B, Soede NM. Relationship between ovulation rate and embryonic characteristics in gilts at 35 d of pregnancy. J Anim Sci 2018; 95:3160-3172. [PMID: 28727117 DOI: 10.2527/jas.2017.1577] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
This study investigated the relationship between ovulation rate (OR) and embryonic characteristics in gilts. Landrace ( = 86) and Yorkshire x Landrace ( = 212) gilts were inseminated with semen stored for 3 to 5 d (SS1, = 59), 6 to7 d (SS2, = 133), or 8 to 10 d (SS3, = 106), and slaughtered at 35 d of pregnancy. Ovulation rate was assessed by dissection of the corpora lutea on both ovaries. Embryos were classified as vital (VE) by visual appearance and individually weighed (VEg) and the SD of the weight calculated (SDVEg). Early embryonic mortality (EM) was estimated as the difference between OR and the number of vital plus nonvital embryos. Embryonic characteristics were analyzed with a model that included linear and quadratic terms of OR and fixed class effects of semen storage duration (SS) and genetic line (GL). Landrace gilts had a higher OR than Yorkshire x Landrace gilts (22.1 ± 0.4 vs. 20.3 ± 0.2, ≤ 0.05) and also a higher EM (6.1 ± 0.4 vs. 3.5 ± 0.3, ≤ 0.05). EM was also higher in gilts inseminated with semen stored for more than 8 d. Also, Yorkshire x Landrace gilts had a higher number of VE (16.9 ± 0.7) than the Landrace gilts (13.3 ± 0.8) when inseminations were done with semen stored for up to 5 d. Yorkshire x Landrace gilts had the highest VEg when inseminated with semen stored for 3 to 5 d (SS1: 4.9 ± 0.2 g, SS2: 4.1 ± 0.1 g, and SS3: 4.0 ± 0.2 g; ≤ 0.05). VE and VEg did not differ within Landrace gilts between different SS classes. A quadratic relationship of OR ( ≤ 0.05) was found with VE: a maximum of 16.8 VE was observed at 26 ovulations [(2.5 (± 0.6)*OR- 0.05 (± 0.01)*OR]. A quadratic relationship of OR ( ≤ 0.05) was also found for EM: a minimum of 3.33 EM was observed at 15 ovulations [(-1.1 (± 0.6)*OR -0.03 (± 0.01)*OR]. VEg was not related with OR, but SDVEg had a positive linear relationship with OR [0.01 (± 0.003)*OR, ≤ 0.05]. Results show that Yorkshire x Landrace gilts perform better than Landrace when inseminated with fresh semen, but not with semen stored for longer time. Also, the VE increases with an increase in OR up to 26, but at a lower level at higher OR, which is likely related with the increase in EM. The higher EM at higher OR might arise from a higher variation in follicular/oocyte quality leading to a higher variation in embryonic quality and development, increasing mortality before uterine implantation and the variation in embryonic weight already at 35 d of pregnancy.
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Da Silva CLA, Laurenssen BFA, Knol EF, Kemp B, Soede NM. Validation of transrectal ultrasonography for assessment of corpora lutea characteristics in pregnant sows and its relationship with litter characteristics at birth. Transl Anim Sci 2017; 1:507-517. [PMID: 32704674 PMCID: PMC7204989 DOI: 10.2527/tas2017.0057] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2017] [Accepted: 09/08/2017] [Indexed: 01/24/2023] Open
Abstract
In experiment 1 we investigated the accuracy of transrectal ultrasonography (TUS) to assess the number (OR) and diameter of corpora lutea (CL) in 45 and 25 sows, respectively, at 23.4 ± 2.9 d of pregnancy. The diameter was calculated as the average diameter of 10 biggest CL. Sows were subsequently slaughtered and OR was assessed by dissection of CL from both ovaries (n = 45) and average diameter of the 10 biggest CL was also calculated after measurement of CL with the caliper rule (n = 25). There was a weak relationship between OR counted after dissection of the ovaries and OR counted with TUS (β = 0.28 ± 0.01 CL/CL, P = 0.01), but there was a strong relationship between the average CL diameter measured with the caliper rule after dissection and the average CL diameter based on TUS (β = 1.0 ± 0.1 mm/mm, P < 0.0001). This shows that TUS is not a valid method to assess OR in pregnant sows but it is a valid method to assess average CL diameter. In experiment 2, we investigated the relationship between the average CL diameter assessed by TUS (n = 100) at 23.8 ± 2.4 d of pregnancy and average piglet birth weight (BW) and observed an increase of 37.6 ± 17.8 g in piglet BW per mm increase in average CL diameter measured by TUS (P = 0.04). This relationship is probably because larger CL develop from bigger follicles at ovulation, which might have ovulated oocytes of higher quality that developed into embryos with higher growth potential and thus higher birth weight.
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van Nieuwamerongen S, Soede N, van der Peet-Schwering C, Kemp B, Bolhuis J. Gradual weaning during an extended lactation period improves performance and behavior of pigs raised in a multi-suckling system. Appl Anim Behav Sci 2017. [DOI: 10.1016/j.applanim.2017.05.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Douthwaite J, Moisan J, Privezentzev C, Soskic B, Sabbah S, Cohen S, Collinson A, England E, Huntington C, Kemp B, Zhuang L, Hudak S, Rees DG, Goldberg D, Barton C, Chang L, Vainshtein I, Liang M, Iciek L, Ambery P, Peakman M, Vaughan TJ, Tree TIM, Sansom DM, Bowen MA, Minter RR, Jermutus L. Correction: A CD80-Biased CTLA4-Ig Fusion Protein with Superior In Vivo Efficacy by Simultaneous Engineering of Affinity, Selectivity, Stability, and FcRn Binding. THE JOURNAL OF IMMUNOLOGY 2017; 199:1943. [DOI: 10.4049/jimmunol.1790013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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van Hoeij RJ, Dijkstra J, Bruckmaier RM, Gross JJ, Lam TJGM, Remmelink GJ, Kemp B, van Knegsel ATM. Consequences of dietary energy source and energy level on energy balance, lactogenic hormones, and lactation curve characteristics of cows after a short or omitted dry period. J Dairy Sci 2017; 100:8544-8564. [PMID: 28822552 DOI: 10.3168/jds.2017-12855] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 07/05/2017] [Indexed: 12/28/2022]
Abstract
Omitting the dry period (DP) generally reduces milk production in the subsequent lactation. The aim of this study was to evaluate the effect of dietary energy source-glucogenic (G) or lipogenic (L)-and energy level-standard (std) or low-on milk production; energy balance (EB); lactogenic hormones insulin, insulin-like growth factor 1 (IGF-1), and growth hormone (GH); and lactation curve characteristics between wk 1 and 44 postpartum in cows after a 0-d or 30-d DP. Cows (n = 110) were assigned randomly to 3 transition treatments: a 30-d DP with a standard energy level required for expected milk yield [30-d DP(std)], a 0-d DP with the same energy level as cows with a 30-d DP [0-d DP(std)], and a 0-d DP with a low energy level [0-d DP(low)]. In wk 1 to 7, cows were fed the same basal ration but the level of concentrate increased to 6.7 kg/d for cows fed the low energy level and to 8.5 kg/d for cows fed the standard energy level in wk 4. From wk 8 postpartum onward, cows received a G ration (mainly consisting of corn silage and grass silage) or an L ration (mainly consisting of grass silage and sugar beet pulp) with the same energy level contrast (low or std) as in early lactation. Cows fed the G ration had greater milk, lactose, and protein yields, lower milk fat percentage, greater dry matter and energy intakes, and greater plasma IGF-1 concentration compared with cows fed the L ration. Dietary energy source did not affect EB or lactation curve characteristics. In cows with a 0-d DP, the reduced energy level decreased energy intake, EB, and weekly body weight gain, but did not affect milk production or lactation curve characteristics. A 30-d DP resulted in a greater total predicted lactation yield, initial milk yield after calving, peak milk yield, energy intake, energy output in milk, days to conception [only when compared with 0-d DP(low)], plasma GH concentration [only when compared with 0-d DP(std)], and decreased weekly body weight gain compared with a 0-d DP. A 30-d DP decreased both the increasing and the declining slope parameters of the lactation curve and the relative rate of decline in milk yield (indicating greater lactation persistency) compared with a 0-d DP, and decreased plasma insulin and IGF-1 concentration, and EB. In conclusion, feeding a G ration after wk 7 in milk improved energy intake and milk production, but did not affect EB compared with an L ration. For cows without a DP, a reduced dietary energy level did not affect milk production and lactation curve characteristics, but did decrease EB and weekly body weight gain. A 30-d DP increased milk yield and lactation persistency, but decreased milk fat and protein content, EB, and plasma insulin and IGF-1, compared with a 0-d DP.
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Popovic B, Gibson S, Senussi T, Carmen S, Kidd S, Slidel T, Strickland I, Jianqing X, Spooner J, Lewis A, Hudson N, Mackenzie L, Keen J, Kemp B, Hardman C, Hatton D, Wilkinson T, Vaughan T, Lowe D. Engineering the expression of an anti-interleukin-13 antibody through rational design and mutagenesis. Protein Eng Des Sel 2017; 30:303-311. [PMID: 28130326 DOI: 10.1093/protein/gzx001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 01/09/2017] [Indexed: 12/13/2022] Open
Abstract
High levels of protein expression are key to the successful development and manufacture of a therapeutic antibody. Here, we describe two related antibodies, Ab001 and Ab008, where Ab001 shows a markedly lower level of expression relative to Ab008 when stably expressed in Chinese hamster ovary cells. We use single-gene expression vectors and structural analysis to show that the reduced titer is associated with the VL CDR2 of Ab001. We adopted two approaches to improve the expression of Ab001. First, we used mutagenesis to change single amino-acid residues in the Ab001 VL back to the equivalent Ab008 residues but this resulted in limited improvements in expression. In contrast when we used an in silico structure-based design approach to generate a set of five individual single-point variants in a discrete region of the VL, all exhibited significantly improved expression relative to Ab001. The most successful of these, D53N, exhibited a 25-fold increase in stable transfectants relative to Ab001. The functional potency of these VL-modified antibodies was unaffected. We expect that this in silico engineering strategy can be used to improve the expression of other antibodies and proteins.
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