Increased dietary energy alters follicle dynamics and wave patterns in heifers

Understanding the impacts of nutrition on reproductive physiology in cattle are fundamental to improve reproductive efficiency for animals under different nutritional conditions. Starting on Day 0 (day of ovulation) until next ovulation, Holstein heifers (n = 24) were fed: low energy diet (ad libitum grass hay; LED) and high energy diet (ad libitum grass hay + concentrate supplement; HED). Heifers on HED gained more weight (average daily gain: 0.824 ± 0.07 vs 0.598 ± 0.09 kg/day) and had increased insulin concentrations. The dominant follicle of wave 1 in HED had greater growth rate overall from Days 0 to 8 and on Days 6–7 and 8–9 and started atresia later. The dominant follicle of wave 2 in HED had greater growth rate overall from Day 9 to 18 and on Days 14–15 and 15–16. In two-wave patterns, there was no difference in estradiol or progesterone concentrations but concentrations of FSH were lower in HED on Days 15 and 16. Estradiol concentrations increased earlier in two-wave patterns in association with earlier luteolysis. The frequency of two follicular waves was greater in HED than LED (11/12 vs 6/11; 92.7% vs 54.5%). In conclusion, an acute increase in dietary energy altered not only growth rate of the dominant follicle but also follicular wave pattern in heifers by increasing frequency of two follicular waves. The hypotheses were supported that an acute increase in dietary energy (1) prolongs growth period of dominant follicles and (2) alters follicular wave pattern in heifers.

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Ovarian Follicular Dynamics during the Estrous Cycle in Jennies in Upper Egypt

Veterinary Medicine International ◽

10.4061/2011/860518 ◽

2011 ◽

Vol 2011 ◽

pp. 1-6 ◽

Cited By ~ 6

Author(s):

R. I. Derar ◽

H. A. Hussein

Keyword(s):

Growth Rate ◽

Estrous Cycle ◽

Slow Rate ◽

Ovarian Follicles ◽

Maximum Diameter ◽

Dominant Follicle ◽

Upper Egypt ◽

Follicular Wave ◽

Preovulatory Follicles ◽

Follicular Dynamics

The objective of the current study was to describe follicular dynamics in Egyptian Jennies throughout the estrous cycle. In this experiment, 8 estrus cycles in 8 cyclic Jennies were studied from February to June using ultrasonography. The result revealed that one follicular wave per cycle was recorded throughout the studied period. Dominant follicle (DF) was firstly detected at day in Jennies. The growth rate of DF was mm/day. Left ovulations were nonsignificantly () more than right ovulations (55.6% versus 44.6%). The CL was firstly detected at D , developed in a rate of mm/day, reached a maximum diameter of mm at D , and started to regress on D with a mean regression rate of mm d-1. Results of the present study indicated that Jennies had one follicular wave per cycle. The Day of the cycle has a significant effect on the number of different classes of the ovarian follicles, but not large ones. Ultrasonographic characteristics of the preovulatory follicles could be useful to predict ovulation. CL developed and regressed in a slow rate.

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Effect of the dominant follicle on regression of its subordinates in heifers

Canadian Journal of Animal Science ◽

10.4141/cjas93-029 ◽

1993 ◽

Vol 73 (2) ◽

pp. 267-275 ◽

Cited By ~ 68

Author(s):

G. P. Adams ◽

K. Kot ◽

C. A. Smith ◽

O. J. Ginther

Keyword(s):

Key Words ◽

Maximum Diameter ◽

Sham Operation ◽

Dominant Follicle ◽

Follicular Waves ◽

Follicular Wave ◽

The Relationship ◽

Small Follicle

The relationship between a dominant follicle of a follicular wave and the suppression of subordinate follicles was studied during the first postovulatory wave (Wave 1) in Holstein heifers. The dominant follicle (largest follicle) was cauterized or a sham-operation was done on day 3 (day 0 = ovulation) using seven heifers per group. In the cautery group, compared to the controls, the largest subordinate follicle attained a larger diameter (11 7 vs 8 0 mm; P < 0.01), reached maximum diameter at a later day (day 9.2 vs. day 3.1; P < 0 01) and began to regress at a later day (day 14.3 vs. day 5.7; P < 0.01). In addition, the emergence of Wave 2 was hastened (day 6.4 vs. day 9.3; P < 0.05) and more heifers had more than two waves per interovulatory interval (5 of 6 vs. 2 of 7; P < 0.05). In heifers with the dominant follicle eliminated, the largest subordinate grew to the diameter of a dominant follicle during Wave 1 (n = 3) or became the dominant follicle of a newly emerged wave (n = 2). A subordinate sometimes persisted as a small follicle (e.g., 5 mm) for several days before resurging. However, it was not convincingly demonstrated that a subordinate follicle could resurge after it had begun to regress (decrease in diameter). Results supported the hypothesis that suppression of subordinate follicles is a prolonged process, so that resurgence of a subordinate can occur if the dominant follicle is removed. Key words: Ovaries, follicular waves, selection, cattle, cauterization

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Follicular dynamic and repeatability of follicular wave development in Peranakan Ongole (PO) cattle

Jurnal Ilmu Ternak dan Veteriner ◽

10.14334/jitv.v21i1.1349 ◽

2016 ◽

Vol 21 (1) ◽

pp. 26 ◽

Cited By ~ 1

Author(s):

Muhammad Imron ◽

Iman Supriatna ◽

. Amrozi ◽

Mohamad Agus Setiadi

Keyword(s):

Bos Taurus ◽

Research Result ◽

Bos Indicus ◽

Follicular Development ◽

Wave Pattern ◽

Follicular Wave ◽

Follicle Diameter ◽

Wave Patterns ◽

The Difference ◽

Follicular Dynamics

Superovulation treatment on PO cattle (Bos indicus) was less responsive compared to Bos taurus breed. It might due to the difference of their follicular dynamic. This study was conducted to investigate the follicular dynamics and its repeatability in PO cattle. Follicular dynamics observations conducted on 9 cows trough ultrasound scanning every day. Observations of wave patterns repeatability were performed in 6 cows which its wave pattern already known on the next consecutive IOI. Research result indicated that PO cattle had 3 (66%) and 4-waves (34%) pattern. The first wave of 3 and 4-waves pattern emerged on day -0.4+0.9 and 1.4+1.1 respectively. The second wave of 3 and 4-wave pattern emerged on day 9.8+1.5 and 7.4+1.9 respectively. The pattern of 3 waves has a longer follicle dominant duration (11.6+1.5 day) in the first wave of estrous cycle, compared with 4 waves pattern (10+2.92 and 7+1.00 day respectively). The growth rate of dominant follicle was not different significantly between the 3 and 4-waves pattern (0.87+0.23 and 0.94+0.25 mm/day respectively). Similarly, ovulatory follicle diameter between 3 and 4-waves pattern was also not different significantly (12.24+12.34 and 12.30+12.23 mm respectively). Observation of wave patterns repeatability in 6 PO cows indicated that PO cattle had high repeatability in follicular wave pattern (0.88) and the number of growing follicle was 0.91. This study resulted data for dynamic of follicular development, wave pattern, its repeatability which be expected to design the protocol of superovulation treatment or other reproduction technologies based on follicular dynamic to improve its result in PO cattle.

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Ovarian follicle growth dynamics during the postpartum period in Holstein cows and effects of contemporary cyst occurrence

Czech Journal of Animal Science ◽

10.17221/6414-cjas ◽

2012 ◽

Vol 57 (No. 12) ◽

pp. 562-572 ◽

Cited By ~ 3

Author(s):

R. Rajmon ◽

J. Šichtař ◽

L. Vostrý ◽

D. Řehák

Keyword(s):

Growth Rate ◽

Ovarian Follicle ◽

Follicular Development ◽

Growth Dynamics ◽

Hormonal Treatment ◽

Maximum Size ◽

Experimental Period ◽

Follicular Waves ◽

Follicular Wave ◽

Follicular Cyst

The indicators of follicle development with regard to the growth wave order, the first ovulation, animal parity, and also with regard to the simultaneous presence or absence of a follicular cyst were determined in cows in the course of 60 days postpartum. Follicular dynamics were monitored daily by ultrasonography. The animals were assigned to three groups based on the time of the 1st ovulation: G1 (n = 9) – the 1st dominant follicle (DF) ovulated, G2 (n = 10) – ovulation occurred on the 2nd or later follicular waves, and G3 (n = 5) – no ovulation occurred during the experimental period. G1 animals showed better fertility later (no cyst, less days open, P = 0.07, less hormonal treatment, P = 0.008). The rhythm of follicular wave development was generally similar in all the animals (based on emergence of the first follicular wave, the interval from emergence to deviation, and the number of all follicular waves). Nevertheless, emergence of follicular waves and deviation occurred by 0.5–0.9 day earlier in primiparous than in multiparous cows and in G1 vs. G2, or G3, respectively (in all P < 0.05). DF development was independent of parity as well as group effects, but the maximum size and growth rate (1.2 vs. 0.8 cm/day, P < 0.05) were higher in ovulatory follicles (OF) than in regressive ones (rDF). The presence of a growing cyst decreased the probability of rDF as well as OF development (P < 0.0001). The OF growth rate was faster in the milieu of a stagnating cyst than without any cyst (P < 0.04). Therefore, the development of follicles was dramatically suppressed beyond, but nor before, deviation in the milieu of a growing cyst. Cessation of the cyst growth accelerated the development of OFs. On the contrary, a cystic structure without any significant growth can persist for weeks with no effect on successful follicular development.

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223DEVELOPMENTAL PATTERN OF SMALL (1-3mm) ANTRAL FOLLICLES IN THE BOVINE OVARY

Reproduction Fertility and Development ◽

10.1071/rdv16n1ab223 ◽

2004 ◽

Vol 16 (2) ◽

pp. 233

Author(s):

R.S. Jaiswal ◽

J. Singh ◽

G.P. Adams

Keyword(s):

Repeated Measures ◽

Wave Pattern ◽

Developmental Pattern ◽

Dominant Follicle ◽

Antral Follicles ◽

Follicular Wave ◽

Statistical Analysis System ◽

The Future ◽

Bovine Ovary ◽

Analysis System

Knowledge about the developmental pattern of small follicles (<4mm) will be crucial to understanding the endogenous control of folliculogenesis and to developing methods to control it for clinical purposes. This study was designed to characterize the developmental pattern of 1–3mm follicles and to determine, retrospectively, the stage at which the future dominant follicle first attains a size advantage among follicles in the cohort. In Experiment 1, the ovaries of Hereford-cross heifers (n=18) were examined daily by high resolution transrectal ultrasonography for one natural interovulatory interval to evaluate changes in the number of 1–3-mm follicles in relation to the wave pattern of follicles ≥4mm. Interovulatory interval was divided into 2- and 3-wave based on number of waves exhibited by heifers. In Experiment 2, the ovaries of Hereford-cross cows (n=9) were examined every 6h from Day 5 to Day 13 (Day 0=ovulation) to monitor precisely the diameter changes of individual follicles ≥1mm during emergence of the second follicular wave. Data were analyzed by Proc. Mixed procedure for repeated measures (Littell RC et al., 2000 Stat in med 19, 1793–1819) in the Statistical Analysis System software package (SAS version 8.2 for MS Windows;; 2002 SAS Institute Inc. Cary, NC, USA). Results of Experiment 1 revealed a day effect (P<0.05) on the number of small (1–3mm) follicles, with a peak (P<0.05) 1 or 2 days before wave emergence (defined as the day the dominant follicle was first detected at 4mm), followed 3 to 4 days later by a peak (P<0.05) in the number of large follicles (≥4mm). There was an inverse relationship between the number of small and large follicles during Wave 1 (r=−0.66; P=0.05) and Wave 2 (r=−0.62; P=0.04) in 2-wave interovulatory intervals. Similarly, an inverse relation was detected between the number of small and large follicles for Wave 1 (r=−0.79; P=0.01) and Wave 3 (r=−0.90; P<0.01) but not for Wave 2 (r=−0.57; P=0.14) in 3-wave interovulatory intervals. The number of 1–3-mm follicles detected in anovulatory waves did not differ (P=0.53) between 2- versus 3-wave interovulatory intervals;; however, a difference (P<0.05) was observed between anovulatory and ovulatory waves in 3-wave interovulatory intervals but not (P=0.63) in 2-wave interovulatory intervals. Experiment 2 permitted the identification of the future dominant follicle at a diameter of 1mm and its emergence at 6–12h earlier than the largest subordinate follicle (P<0.01). Emergence of the future dominant (r=0.71; P=0.05) and 1st subordinate (r=0.78; P=0.02) follicles was temporally associated with a wave-eliciting rise in circulating concentrations of FSH. Growth rate of the dominant and the 1st subordinate follicle differed (P<0.01) from 2nd subordinate follicle at 84h after their detection at 1mm. It was concluded that small antral follicles (1–3mm) develop in a wave-like manner, and apparent selection of the dominant follicle was manifest much earlier than previously documented.

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Comparación ultrasonográfica transvaginal y transrectal de la dinámica folicular en ondas sucesivas de llamas (Lama glama)

Revista de Investigaciones Veterinarias del Perú ◽

10.15381/rivep.v32i1.19504 ◽

2021 ◽

Vol 32 (1) ◽

pp. e19504

Author(s):

Uri Perez G. ◽

David Pari P. ◽

Fidel Gutierrez Y. ◽

Julio Málaga A. ◽

Natalio Luque M. ◽

...

Keyword(s):

Growth Rate ◽

Negative Correlation ◽

Reproductive Season ◽

Maximum Diameter ◽

Follicular Waves ◽

Follicular Wave ◽

Linear Transducer ◽

Lama Glama ◽

The Relationship ◽

Follicular Dynamics

La dinámica folicular ovárica monitoreada por vía transrectal (TR) y transvaginal (TV) en ondas sucesivas en llamas fue estudiada en 10 llamas con más de 4 años, multíparas, sin cría, estado corporal de 3.0, durante un periodo de 90 días en la época reproductiva. Se utilizó el ecógrafo Sonostar SS8® con un transductor lineal para el examen transrectal y transductor microconvexo endocavitario para el examen transvaginal, ambos con frecuencia de 6.5 MHz. El intervalo inter-onda fue de 20±4.4 y 22.5±5.3 por vía TR y TV, respectivamente; el número de folículos por cohorte fue 5.21±0.92 y 6.38±1.26 para TR y TV, respectivamente (p=0.0011); el diámetro máximo de folículos fue 12.49±3.57 mm para TR y 13.56±3.91 mm para TV; la tasa de crecimiento fue de 0.70±0.35 y 0.67±0.32 mm/día para TR y TV, respectivamente. La ecuación de regresión para relación del diámetro máximo folicular y duración de onda folicular vía TR fue de y=0.89766x+6.5554 (R²=0.423) y para la vía TV de y=0.8466x+10.184 (R²=0.479). La duración de las fases foliculares fue similar entre ambas técnicas con excepción de la fase de dominancia (10.2±3.19 días para TR y 8.67±2.46 para TV, p=0.0418). La relación entre el diámetro folicular y número de folículos detectados presentó una correlación negativa baja (R²=-0.0827 para TV y R²=-0.0876 para TR). En conclusión, el transductor endocavitario transvaginal permite determinar con mayor precisión las características de dinámica folicular en llamas en sus fases de reclutamiento, dominancia y regresión con sobreposición de ondas foliculares como característica importante.The ovarian follicular dynamics monitored by transrectal (TR) and transvaginal (TV) routes in successive waves was studied in 10 llamas older than 4 years, multiparous, without calves at foot, body condition of 3.0, during a period of 90 days in the reproductive season. The Sonostar SS8® ultrasound equipment was used with a linear transducer for transrectal examination and endocavitary microconvex transducer for transvaginal examination, both with a frequency of 6.5 MHz. The inter-wave interval was 20 ± 4.4 and 22.5 ± 5.3 via TR and VT, respectively; the number of follicles per cohort was 5.21 ± 0.92 and 6.38 ± 1.26 for TR and TV, respectively (p=0.0011); the maximum diameter of follicles was 12.49 ± 3.57 mm for TR and 13.56 ± 3.91 mm for TV; the growth rate was 0.70 ± 0.35 and 0.67 ± 0.32 mm/day for TR and TV, respectively. The regression equation for the ratio of the maximum follicular diameter and duration of follicular wave via TR was y=0.89766x+6.5554 (R²=0.423) and for the TV route y=0.8466x+10.184 (R²=0.479). The duration of the follicular phases was similar between both techniques except for the dominance phase (10.2±3.19 days for TR and 8.67±2.46 for TV, p=0.0418). The relationship between the follicular diameter and the number of follicles detected showed a low negative correlation (R²=-0.0827 for TV and R²=-0.0876 for TR). In conclusion, the transvaginal endocavitary transducer makes it possible to determine with greater precision the characteristics of llama follicular dynamics in their recruitment, dominance and regression phases with overlapping of follicular waves as an important characteristic.

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The effects of acute nutritional restriction on LH and oestradiol concentrations, follicle dynamics and fertility in heifers

BSAP Occasional Publication ◽

10.1017/s0263967x00034169 ◽

2001 ◽

Vol 26 (2) ◽

pp. 479-483

Author(s):

D.R. Mackey ◽

J.F. Roche ◽

J.M. Sreenan ◽

M.G. Diskin

Keyword(s):

Growth Rate ◽

Maximum Diameter ◽

Dominant Follicle ◽

Beef Heifers ◽

Lh Surge ◽

Suppression Effect ◽

Follicular Wave ◽

Nutritional Restriction ◽

Pulse Characteristics ◽

Follicle Maturation

AbstractThe effects of acute nutritional change on endocrine and ovarian parameters were studied in two experiments. In both experiments, cyclic beef heifers fed a diet of 1.2 times maintenance (1.2 M) were synchronised using an intravaginal progesterone releasing device which was removed after 8 days. In Experiment 1, heifers were randomly allocated to a diet of either 0.4, 1.2 or 2.0 M one day before progesterone withdrawal. The dominant follicle present at progesterone withdrawal (synchronised DF) failed to ovulate in 2/8 heifers fed 0.4 M, and both growth rate (P<0.05) and maximum diameter (P<0.05) of the first new follicular wave was less than in heifers fed either 1.2 or 2.0 M. There was no effect of diet on LH pulse characteristics at emergence, selection or dominance phases of the first follicle wave of the next cycle (P>0.10). Due to anovulation of the synchronised DF in Experiment 1, a further experiment was conducted (Experiment 2) to examine pro-oestrus oestradiol and LH concentrations at both ovulation of the synchronised DF and prostaglandin-induced ovulation of the first DF of the next cycle (when insemination was performed). All heifers had a pro-oestrus increase in the concentration of oestradiol following progesterone withdrawal, but 2 heifers fed 0.4 M did not have an LH surge and did not ovulate. The first DF after the synchronised DF failed to ovulate in 12/20 heifers fed 0.4 M (P<0.05), always preceded by absence of a pro-oestrus increase in oestradiol and an LH surge. Where heifers ovulated, there was no effect of diet on conception rate. We conclude that acute nutritional restriction of beef heifers caused an immediate suppression in the growth rate and maximum diameter of dominant follicles, but this occurred without any suppression effect on LH pulse characteristics. Restriction to 0.4 M induced anovulation in 60% of heifers within 14 days and this was preceded by the absence of an LH surge. Where ovulation did occur, acute NEB in the final stages of follicle maturation did not appear to affect pregnancy rate.

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Effect of progesterone administration during growing phase of first dominant follicle on follicular wave pattern in buffalo heifers

Tropical Animal Health and Production ◽

10.1007/s11250-019-02143-2 ◽

2019 ◽

Vol 52 (3) ◽

pp. 1395-1402

Author(s):

M. H. Jan ◽

H. Kumar ◽

S. Kumar ◽

R. K. Sharma ◽

A. Gupta ◽

...

Keyword(s):

Wave Pattern ◽

Dominant Follicle ◽

Follicular Wave

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121 Ovulatory response to gonadotropin-releasing hormone relative to day and diameter of dominant follicle during the first follicular wave in Beetal goats

Reproduction Fertility and Development ◽

10.1071/rdv31n1ab121 ◽

2019 ◽

Vol 31 (1) ◽

pp. 186

Author(s):

W. Ahmad ◽

M. I.-R. Khan ◽

A. Murtaza ◽

I. Mohsin ◽

A. Riaz ◽

...

Keyword(s):

Growth Rate ◽

Prostaglandin F2α ◽

Binary Logistic Regression ◽

Gonadotropin Releasing Hormone ◽

Oestrous Cycle ◽

New Wave ◽

Dominant Follicle ◽

Releasing Hormone ◽

Follicular Wave ◽

Ovulatory Follicles

In Beetal goats under subtropical conditions, ovulatory response of first-wave dominant follicle based on diameter and day of oestrous cycle is unknown to date. The objective of this study was to evaluate the ovulatory response to gonadotropin-releasing hormone (GnRH) relative to day and diameter of dominant follicle during the first follicular wave in Beetal goats. Fifty goats were synchronized using a single dose of prostaglandin F2α (75 µg; D+ cloprostenol, Fatro, Italy), and scanned every 6 hours for ovulation using a 7.5-MHz trans-rectal transducer (Honda HS: 1500, Japan). Following ovulation (Day 0), goats (n=40; 10/day) were given GnRH (25µg lecirelin, Fatro, Italy) on Days 2, 4, 6, and 8 of oestrous cycle. Follicular dynamics was monitored daily from D 0 until GnRH, and every 4 hours after GnRH until ovulation. Ovulation frequency relative to day and dominant follicular diameter was analysed by binary logistic regression, whereas diameter of dominant follicle at time of GnRH, ovulation time, time of wave emergence and growth rate of dominant follicle following GnRH were analysed by one-way ANOVA and independent sample t-test (SPSS 20, IBM Corp., Armonk, NY, USA). Eighty percent of the goats ovulated within 74.7±1.3h after prostaglandin F2α. Overall, 37% (14/38) of the goats ovulated following GnRH within 12.0±1.5h. Ovulations (%) following GnRH were higher (P=0.03) on Day 4 than 2 (60 v. 10%; i.e. 14 times higher than Day 2) and decreased gradually from Day 4 to 8 (P>0.05). Similarly, ovulations following GnRH were higher (P=0.00) in first-wave dominant follicles having diameter 6.1-7.0mm than those having less than 6.1mm (88v. 23%; i.e. 24 times higher than <6.1mm). Ovulations (%) decreased as the diameter of dominant follicle increased from 6.1-7.0mm (P>0.05). Diameters of ovulatory follicles at time of GnRH between Day 2, 4, 6, and 8 were not different (P>0.05). Regardless of day of GnRH treatment, diameter of ovulatory v. anovulatory follicles differed (6.44±0.03v. 5.1±0.4 mm; P=0.00). Overall, growth rate of dominant follicles following GnRH was 0.2±0.11mm and did not differ between ovulatory and anovulatory goats (0.29±0.13v. 0.13±0.15 mm; P>0.05). Interval to the emergence of a new wave following GnRH was prolonged for Day 4 compared to Day 2, 6, and 8 (i.e. 22v. 8, 11, and 12 h; respectively, P<0.05). In conclusion, GnRH treatment at Day 4 resulted in maximum ovulations as the first-wave dominant follicle reached a size of 6.1 to 7.0 mm.

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Effect of dam nutrition and suckling on lactation in Borana cows and growth in their Borana × Friesian crossbred calves in an early weaning system in Ethiopia

Animal Science ◽

10.1017/s0003356100007030 ◽

1994 ◽

Vol 58 (1) ◽

pp. 19-24 ◽

Cited By ~ 2

Author(s):

A. Tegegne ◽

P. O. Osuji ◽

A. Lahlou-Kassi ◽

E. Mukasa-Mugerwa

Keyword(s):

Growth Rate ◽

Production Systems ◽

Bos Indicus ◽

Cow Milk ◽

Small Scale ◽

Early Weaning ◽

Concentrate Supplementation ◽

Grass Hay ◽

Feeding Regimes ◽

Ad Libitum

AbstractForty-four Borana × Friesian F1 crossbred calves born to Borana (Bos indicus) cows were randomly assigned to either suck their dams hvice daily or bucket-feeding with 1341 milk over a 57-day pre-weaning period. Their dams were also allocated either to a supplement group with grass hayad libitumand 5 kg per head per day of a concentrate ration or to an unsupplemented group withad libitumgrass hay only. Calves were fed in individual boxes in a calf house. The mean birth weight of calves was 24·8 (s.e. 1·8) kg. Suckled calves were heavier (P < 0·01) at weaning (47·7 (s.e. 1·9) v.37·1 (s.e. 1·8) kg) and had faster pre-weaning growth rate (411 (s.e. 30)v.215 (s.e. 29) g/day) than bucket-fed calves. Calves which sucked supplemented cows were heavier (P < 0·001) at weaning (51·2 (s.e. 2·6)v. 44·2 (s.e. 2·6) kg), had faster (P < 0·01) pre-weaning growth rate (477 (s.e. 41)v.346 (s.e. 41) glday) and higher (P<0·01) daily milk intake (2·6 (s.e. 0·2)v.1·6 (s.e. 0·2) I/day) than those which sucked unsupplemented cows. Mean concentrate intake was 302 (s.e. 30) g/day for bucket-fed calves and 341 (s.e. 33) and 408 (s.e. 33) g/day for calves which sucked supplemented and unsupplemented cows. Cow milk production was higher (P < 0·01) in suckled than in milked cows (3·3 (s.e. 0·2)v.1·0 (s.e. 0·2) I/day) and in supplemented than unsupplemented cows (3·9 (s.e. 0·2)v.2·7 (s.e. 0·2) I/day). Concentrations of milk protein, fat and total solids averaged 39 (s.e. 15), 49 (s.e. 16) and 143 (s.e. 21) g/kg, respectively and were not significantly influenced by either concentrate supplementation or suckling. Restricted suckling and early weaning coupled with appropriate calf and cow feeding regimes could be one of the alternatives for calf rearing under smallholder and small scale peri-urban dairy production systems. However, further studies are warranted to evaluate the effects of such a strategy on both calf and cow performances under these production systems.

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